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Zeng D, Wang S, Wei X, Zhang S, Zhou H, Hu X, Fu X, Li Y, Wei Z. The effect of microvascular decompression of the CN IX-X root entry/exit zone and the ventrolateral medulla in neurogenic hypertension involving the vertebral/basilar artery. Front Neurol 2024; 15:1376019. [PMID: 38957353 PMCID: PMC11218759 DOI: 10.3389/fneur.2024.1376019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 05/23/2024] [Indexed: 07/04/2024] Open
Abstract
Introduction Neurogenic hypertension (HTN) is a type of HTN characterized by increased activity of the sympathetic nervous system. Vascular compression is one of the pathogenic mechanisms of neurogenic HTN. Despite Jannetta's solid anatomical and physiological arguments in favor of neurogenic HTN in the 1970's, the treatment for essential HTN by microvascular decompression (MVD) still lacks established selection criteria. Therefore, the subjects selected for our center were limited to patients with primary trigeminal neuralgia (TN) and primary hemifacial spasm (HFS) of the vertebral/basilar artery (VA/BA) responsible vessel type coexisting with neurogenic HTN who underwent MVD of the brainstem to further explore possible indications for MVD in the treatment of neurogenic HTN. Methods A retrospective analysis of 63 patients who were diagnosed with neurogenic HTN had symptoms of HFS and TN cranial nerve disease. Patients were treated at our neurosurgery department from January 2018 to January 2023. A preoperative magnetic resonance examination of the patients revealed the presence of abnormally located vascular compression in the rostral ventrolateral medulla (RVLM) and the root entry zone (REZ) of the IX and X cranial nerves (CN IX- X). Results There was no significant difference between the two groups in terms of gender, age, course of HFS, course of TN, course of HTN, degree of HTN, or preoperative blood pressure. Based on the postoperative blood pressure levels, nine out of 63 patients were cured (14.28%), eight cases (12.70%) showed a marked effect, 16 cases (25.40%) were effective, and 30 cases were invalid (47.62%). The overall efficacy was 52.38%. However, 39 cases of combined cranial nerve disease were on the left side of the efficacy rate (66.67%) and 24 cases of combined cranial nerve disease were on the right side of the efficacy rate (29.16%). Discussion Over the last few decades, many scholars have made pioneering progress in the clinical retrospective study of MVD for neurogenic hypertension, and our study confirms the efficacy of MVD in treating vertebral/basilar artery-type neurogenic hypertension by relieving the vascular pressure of RVLM. In the future, with the development and deepening of pathological mechanisms and clinical observational studies, MVD may become an important treatment for neurogenic hypertension by strictly grasping the surgical indications. Conclusion MVD is an effective treatment for neurogenic HTN. Indications may include the following: left-sided TN or HFS combined with neurogenic HTN; VA/BA compression in the left RVLM and REZ areas on MRI; and blood pressure in these patients cannot be effectively controlled by drugs.
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Affiliation(s)
- Defeng Zeng
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- Department of Graduate School, Dalian Medical University, Dalian, China
| | - Shiyao Wang
- Department of Graduate School, Dalian Medical University, Dalian, China
- Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Xingrong Wei
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- Department of Graduate School, Dalian Medical University, Dalian, China
| | - Shuguang Zhang
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Hao Zhou
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- Department of Graduate School, Dalian Medical University, Dalian, China
| | - Xueqian Hu
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- Department of Graduate School, Dalian Medical University, Dalian, China
| | - Xin Fu
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Yang Li
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Zhenqing Wei
- Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
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Giammattei L, Wuerzner G, Theiler K, Vollenweider P, Dunet V, Al Barajraji M, Squair JW, Bloch J, Daniel RT. Lateral medullary vascular compression manifesting as paroxysmal hypertension. Acta Neurochir (Wien) 2024; 166:139. [PMID: 38488893 PMCID: PMC10943153 DOI: 10.1007/s00701-024-06032-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 03/05/2024] [Indexed: 03/17/2024]
Abstract
Neurovascular compression of the rostral ventrolateral medulla (RVLM) has been described as a possible cause of refractory essential hypertension. We present the case of a patient affected by episodes of severe paroxysmal hypertension, some episodes associated with vago-glossopharyngeal neuralgia. Classical secondary forms of hypertension were excluded. Imaging revealed a neurovascular conflict between the posterior inferior cerebellar artery (PICA) and the ventrolateral medulla at the level of the root entry zone of the ninth and tenth cranial nerves (CN IX-X REZ). A MVD of a conflict between the PICA and the RVLM and adjacent CN IX-X REZ was performed, resulting in reduction of the frequency and severity of the episodes. Brain MRI should be performed in cases of paroxysmal hypertension. MVD can be considered in selected patients.
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Affiliation(s)
- L Giammattei
- Department of Neurosurgery, Lausanne University Hospital, Lausanne and University of Lausanne, Lausanne, Switzerland.
| | - G Wuerzner
- Service of Nephrology and Hypertension, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - K Theiler
- Service of Nephrology and Hypertension, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - P Vollenweider
- Department of Medicine, Internal Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - V Dunet
- Department of Medical Radiology, Service of Diagnostic and Interventional Radiology, Neuroradiology Unit, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - M Al Barajraji
- Department of Neurosurgery, Lausanne University Hospital, Lausanne and University of Lausanne, Lausanne, Switzerland
| | - J W Squair
- Department of Neurosurgery, Lausanne University Hospital, Lausanne and University of Lausanne, Lausanne, Switzerland
| | - J Bloch
- Department of Neurosurgery, Lausanne University Hospital, Lausanne and University of Lausanne, Lausanne, Switzerland
- Defitech Center for Interventional Neurotherapies (NeuroRestore), CHUV/UNIL/EPFL, 1005, Lausanne, Switzerland
- Department of Clinical Neuroscience, Lausanne University Hospitzal (CHUV) and University of Lausanne (UNIL), 1005, Lausanne, Switzerland
| | - R T Daniel
- Department of Neurosurgery, Lausanne University Hospital, Lausanne and University of Lausanne, Lausanne, Switzerland
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Manava P, Hastreiter P, Schmieder RE, Jung S, Fahlbusch R, Dörfler A, Lell MM, Buchfelder M, Naraghi R. Neurovascular Compression in Arterial Hypertension: Correlation of Clinical Data to 3D-Visualizations of MRI-Findings. Open Neuroimag J 2021. [DOI: 10.2174/1874440002114010016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aims:
In this study, we attempted to identify clinical parameters predicting the absence or presence of Neurovascular Compression (NVC) at the Ventrolateral Medulla (VLM) in arterial hypertension (HTN) in MRI findings.
Background:
Cardiovascular and pulmonary afferences are transmitted through the left vagus and glossopharyngeal nerve to the brain stem and vasoactive centers. Evidence supports the association between HTN and NVC at the left VLM. Several independent studies indicate a reduction of HTN after Microvascular Decompression (MVD) of the left. Several independent studies indicate a reduction of HTN after Microvascular Decompression (MVD) of the left VLM. Image processing of MRI provides comprehensible detection of NVC. HTN affects hemodynamic parameters and organs.
Objective:
This study analyzes and correlates clinical data and MRI findings in patients with and without NVC at the VLM in treatment resistant HTN to obtain possible selection criteria for neurogenic hypertension.
Methods:
In 44 patients with treatment resistant HTN, we compared MRI findings of neurovascular imaging to demographic, clinical and lifestyle data, office and 24-hour ambulatory Blood Pressure (BP), and cardiovascular imaging and parameters.
Results:
Twenty-nine (66%) patients had evidence of NVC at the VLM in MRI. Sixteen patients (36%) had unilateral NVC on the left side, 7 (16%) unilateral right and 6 (14%) bilateral NVC. Fifteen (34%) had no evidence of NVC at the VLM. Patients with left sided NVC were significantly younger, than those without NVC (p=0.034). They showed a statistically significant variance in daytime (p=0.020) and nighttime diastolic BP (p<0.001) as the mean arterial pressure (p=0.020). Other measured parameters did not show significant differences between the two groups.
Conclusion:
We suggest to examine young adults with treatment resistant HTN for the presence of NVC at VLM, before signs of permanent organ damage appear. Clinical and hemodynamic parameters did not emerge as selection criteria to predict NVC. MVD as a surgical treatment of NVC in HTN is not routine yet as a surgical treatment of NVC in HTN is not routine yet. Detection of NVC by imaging and image processing remains the only criteria to suggest MVD, which should be indicated on an individual decision.
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Dodo Y, Takahashi T, Honjo K, Kitamura N, Maruyama H. Measurement of the length of vertebrobasilar arteries: A three-dimensional approach. J Neurol Sci 2020; 414:116818. [DOI: 10.1016/j.jns.2020.116818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 03/11/2020] [Accepted: 04/02/2020] [Indexed: 10/24/2022]
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Efficacy of microvascular decompression on the vascular compression type of neurogenic hypertension: A meta-analysis. Rev Neurol (Paris) 2020; 176:763-769. [PMID: 32169328 DOI: 10.1016/j.neurol.2020.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 02/04/2020] [Accepted: 02/07/2020] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Neurogenic hypertension is a type of hypertension characterized by increased sympathetic activity. Vascular compression is one of the pathogenic mechanisms of neurogenic hypertension. The sample sizes of currently available studies on MVD in the treatment of hypertension are small, and the results are considerably different. Therefore, we conducted a meta-analysis of the previous literature to obtain the most realistic efficiency and analyzed the current situation of MVD as a treatment option of the vascular compression type of neurogenic hypertension. METHOD We systematically searched and identified relevant studies published before July 2019 from PubMed and Embase. Six studies involving 162 participants were included into our final analysis. RESULT The data showed that the effective rate of MVD was 70.1% (95% CI: 0.602-0.801). The most common offending vessel was PICA (29.9%), followed by VA/BA (23.9%) and VA/BA plus PICA (12.7%). Complications were mostly related to the VII, VIII, IX, and/or X cranial nerve dysfunction. CONCLUSION MVD as a treatment option of the vascular compression type of neurogenic hypertension is effective and safe. In spite of this conclusion, more prospective studies are needed to confirm it. On the other hand, a diagnostic method with higher sensitivity and specificity is necessary.
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Kutty RK, Yamada Y, Takizawa K, Kato Y. Medullary Compression Due to Ectatic Vertebral Artery-Case Report and Review of Literature. J Stroke Cerebrovasc Dis 2019; 29:104460. [PMID: 31699578 DOI: 10.1016/j.jstrokecerebrovasdis.2019.104460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/17/2019] [Accepted: 10/02/2019] [Indexed: 11/17/2022] Open
Abstract
Medullary compression syndrome due to anomalous course of blood vessels is a rare disease most commonly seen in the adult population. The offending vessels causing this syndrome are mostly posterior inferior cerebellar artery or the vertebral artery. The symptoms of this syndrome vary from most common hypertension to various other neurologic deficits like hemiplegia, dysesthesia, and dysarthria. Intractable dizziness is a rare symptom of this disease. The definite management plan for this disease is microvascular decompression. We present our case of medullary compression syndrome which manifested as intractable dizziness. We describe our experience in the management of this patient as well as present a review of literature of this rare disease.
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Affiliation(s)
- Raja K Kutty
- Department of Neurosurgery, Government Medical College, Trivandrum, Kerala, India.
| | - Yasuhiro Yamada
- Department of Neurosurgery, Bunbantane Hospital, Fujita Health University, Nagoya, Aichi, Japan
| | - Katsumi Takizawa
- Department of Neurosurgery, Asahikawa Red cross Hospital, Asahikawa, Hokkaido, Japan
| | - Yoko Kato
- Department of Neurosurgery, Bunbantane Hospital, Fujita Health University, Nagoya, Aichi, Japan
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Cavallo C, Safavi-Abbasi S, Kalani MYS, Gandhi S, Sun H, Oppenlander ME, Zabramski JM, Nakaji P, Lawton MT, Spetzler RF. Pulmonary Complications After Spontaneous Aneurysmal Subarachnoid Hemorrhage: Experience from Barrow Neurological Institute. World Neurosurg 2018; 119:e366-e373. [PMID: 30075258 DOI: 10.1016/j.wneu.2018.07.166] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 07/17/2018] [Accepted: 07/19/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVE Because the clinical course of spontaneous aneurysmal subarachnoid hemorrhage (aSAH) can be compromised by pulmonary complications, we sought to review posttreatment outcomes in aSAH patients with and without pulmonary complications. METHODS Patient demographic, clinical, and outcome data (March 2003-January 2007) were analyzed retrospectively. Patients underwent microsurgical or endovascular treatment for aSAH; pulmonary complications were reported. Outcomes were assessed using the Glasgow Outcome Scale (GOS) scores at the 1-year, 3-year, and 6-year follow-up visits. RESULTS The cohort comprised 471 patients (mean age, 53.7 ± 12.4 years; men, 332/471 [70%]). The mean Glasgow Coma Scale (GCS) score at presentation was 11.9 ± 3.0. Of 471 patients, 47% (n = 223) presented with a Hunt and Hess score of ≥3 and 76% (n = 357) with a Fisher grade of 3. Treatment was clipping for 69% (279/407) and coiling for 31% (128/407) of patients. Pulmonary complications occurred in 210 of 471 (45%) patients. Nearly one-half of patients were discharged to home (215/471, 46%), and more than one-half had a good outcome defined as a GOS score of 5 at their 1-year (226/403, 56%), 3-year (217/397, 55%), and 6-year (203/380, 53%) follow-up visits. Logistic regression showed age and GCS scores as outcome predictors at all time points, whereas pulmonary complications predicted poor outcome only at the 1-year follow-up visit. CONCLUSIONS Pulmonary problems represent the most common nonneurologic medical complications after aSAH. Despite advances in critical care, pulmonary complications represented predictors of short-term poor outcome only at the 1-year follow-up visit, whereas the medical history of the patient became more relevant for prognosis in long-term follow-up.
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Affiliation(s)
- Claudio Cavallo
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Sam Safavi-Abbasi
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - M Yashar S Kalani
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA; Department of Neurosurgery, University of Virginia Health System, Charlottesville, Virginia, USA
| | - Sirin Gandhi
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Hai Sun
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Mark E Oppenlander
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Joseph M Zabramski
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Peter Nakaji
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Michael T Lawton
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA
| | - Robert F Spetzler
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
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8
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Martín-Gallego A, González-García L, Carrasco-Brenes A, Segura-Fernández-Nogueras M, Delgado-Babiano A, Ros-Sanjuán A, Romero-Moreno L, Domínguez-Páez M, Dawid-Milner MS, Arráez-Sánchez MA. Brainstem and Autonomic Nervous System Dysfunction: A Neurosurgical Point of View. ACTA NEUROCHIRURGICA. SUPPLEMENT 2017; 124:221-229. [PMID: 28120078 DOI: 10.1007/978-3-319-39546-3_34] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Central autonomic control nuclei and pathways are mainly integrated within the brainstem, especially in the medulla oblongata. Lesions within these structures can lead to central dysautonomia.Central autonomic control structures can be damaged by tumors, during surgery, or by other neurosurgical pathologies. These may elicit clinical or subclinical autonomic complications that can constitute a serious clinical problem.The authors present a broad review of the central autonomic nervous system, its possible dysfunctions, and the relation between neurosurgery and this "not-well-known system". Preliminary results of an autonomic study of brainstem lesions that is currently being carried out by the authors are also shown.
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Affiliation(s)
- A Martín-Gallego
- Department of Neurosurgery, Regional University Hospital of Málaga, Avenida Carlos Haya s/n, 29010, Málaga, Spain.
| | - L González-García
- Department of Neurosurgery, Regional University Hospital of Málaga, Avenida Carlos Haya s/n, 29010, Málaga, Spain
| | - A Carrasco-Brenes
- Department of Neurosurgery, Regional University Hospital of Málaga, Avenida Carlos Haya s/n, 29010, Málaga, Spain
| | - M Segura-Fernández-Nogueras
- Department of Neurosurgery, Regional University Hospital of Málaga, Avenida Carlos Haya s/n, 29010, Málaga, Spain
| | - A Delgado-Babiano
- Department of Neurosurgery, Regional University Hospital of Málaga, Avenida Carlos Haya s/n, 29010, Málaga, Spain
| | - A Ros-Sanjuán
- Department of Neurosurgery, Regional University Hospital of Málaga, Avenida Carlos Haya s/n, 29010, Málaga, Spain
| | - L Romero-Moreno
- Department of Neurosurgery, Regional University Hospital of Málaga, Avenida Carlos Haya s/n, 29010, Málaga, Spain
| | - M Domínguez-Páez
- Department of Neurosurgery, Regional University Hospital of Málaga, Avenida Carlos Haya s/n, 29010, Málaga, Spain
| | - M S Dawid-Milner
- Department of Autonomic Nervous System, CIMES, University of Málaga Foundation (FGUMA), Malaga, Spain
| | - M A Arráez-Sánchez
- Department of Neurosurgery, Regional University Hospital of Málaga, Avenida Carlos Haya s/n, 29010, Málaga, Spain
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Sindou M, Mahmoudi M, Brînzeu A. Hypertension of neurogenic origin: effect of microvascular decompression of the CN IX-X root entry/exit zone and ventrolateral medulla on blood pressure in a prospective series of 48 patients with hemifacial spasm associated with essential hypertension. J Neurosurg 2015; 123:1405-13. [DOI: 10.3171/2014.12.jns141775] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT
In spite of solid anatomical and physiological arguments and the promising results of Jannetta in the 1970s, treating essential hypertension by microvascular decompression (MVD) of the brainstem has not gained acceptance as a mainstream technique. The main reason has been a lack of established selection criteria. Because of this, the authors' attempts have been limited to patients referred for MVD for hemifacial spasm (HFS) who also had hypertension likely to be related to neurovascular compression (NVC).
METHODS
Of 201 patients referred for HFS, 48 (23.8%) had associated hypertension. All had high-resolution MR images that demonstrated NVC. All underwent MVD of the root exit/entry zone (REZ) of the ninth and tenth cranial nerves (CN IX-X) and adjacent ventrolateral medulla in addition to the CN VII REZ. Effects on hypertension, graded using the WHO classification, were studied up to the latest follow-up, which was 2–16 years from the time of surgery, 7 years on average. Also, effects of MVD on blood pressure (BP) according to the side of vascular compression were evaluated.
RESULTS
Preoperatively, hypertension was severe in all but 1 of the patients; in spite of medical treatment, 47 patients still had WHO Grade 1 or 2 hypertension, and 18 still had unstable BP. After MVD, at latest follow-up, BP had returned to normal (i.e., systolic pressure < 140 mm Hg) in 28 patients; 14 of these patients (29.10% of the whole series) were able to maintain normal BP without any antihypertensive treatment; the other 14 still required some medication to maintain their BP below 140 mm Hg (p < 0.0001). Also, at latest follow-up, BP remained unstable in only 8 of the 18 patients with instability prior to MVD (p < 0.02). Analysis according to side of compression showed that of the 30 patients with left-sided compression, 17 had their BP normalized (without medication in 11 cases), and of the 18 patients with right-sided compression, 11 had their BP normalized (without medication in 3 cases). The difference between sides was not significant.
CONCLUSIONS
These results argue for considering MVD for the treatment of hypertension likely to be due to NVC at the CN IX-X REZ and adjacent ventrolateral medulla. Criteria for selecting patients with hypertension alone still need to be established and could include the following indications: apparently essential hypertension, likely to be neurogenic, in patients in whom high-resolution MRI shows clear-cut images of NVC at the CN IX-X REZ and adjacent ventrolateral medulla and in whom BP cannot be controlled by medical treatment.
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Affiliation(s)
- Marc Sindou
- 1Department of Neurosurgery, University of Lyon 1, Hôpital Neurologique “Pierre Wertheimer,” Lyon, France
| | - Mohamed Mahmoudi
- 1Department of Neurosurgery, University of Lyon 1, Hôpital Neurologique “Pierre Wertheimer,” Lyon, France
- 2Section of Neurosurgery, Regional Military Hospital of Oran (HMRUO), Oran, Algeria; and
| | - Andrei Brînzeu
- 1Department of Neurosurgery, University of Lyon 1, Hôpital Neurologique “Pierre Wertheimer,” Lyon, France
- 3University of Medicine “Victor Babes,” Timisoara, Romania
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Rudzińska M, Wójcik-Pędziwiatr M, Malec-Litwinowicz M, Grabska N, Hartel M, Flak M, Szczudlik A. Is hypertension a risk factor of hemifacial spasm? Neurol Neurochir Pol 2015; 50:69-74. [PMID: 26969561 DOI: 10.1016/j.pjnns.2015.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 10/20/2015] [Accepted: 11/07/2015] [Indexed: 11/29/2022]
Abstract
OBJECTIVES The published data on the relation between arterial hypertension (AH) and hemifacial spasm (HFS) are controversial. The aim of the study was to determine the prevalence of AH in HFS patients and the relation of AH and compression of the brainstem at the region of vasomotor center. MATERIALS AND METHODS The study included 60 of primary HFS patients and 60 healthy controls matched by age. AH was defined according to WHO criteria. The vessel compression of the brainstem was measure on MRI scans in selected region of vasomotor center located in the ventro-lateral medulla (VLM), between the pontomedullary junction, retro-olivary sulcus and the root entry zone (REZ) of the IX and X nerves. Modeling and compression severity of the VLM was graded in the 0-3 scale. RESULTS The prevalence of AH in HFS patients did not differ significantly from the control group (61.6% vs 45.0%, p=ns). VML compression by vessel was frequently found in HFS patients with AH than without AH (97.2% vs 60.9%, χ(2)=11.0, p=0.0009). A similar relation was also found in the control group. The higher rate of VML vascular compression was related to the presence of AH in both, HFS patients and control group. CONCLUSION The prevalence of AH in HFS patients does not differ from controls. The VLM compression in HFS patients and controls is related to AH diagnosis. The association between AH and VLM compression is stronger in patients with higher degree of VLM compression.
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Affiliation(s)
- Monika Rudzińska
- Department of Neurology, Medical University of Silesia, Faculty of Medicine, Katowice, Poland.
| | - Magdalena Wójcik-Pędziwiatr
- Department of Neurology with Unit of Stroke and Unit of Neurological Rehabilitation, The John Paul II Hospital, Krakow, Poland
| | - Michalina Malec-Litwinowicz
- Department of Neurology with Unit of Stroke and Unit of Neurological Rehabilitation, The John Paul II Hospital, Krakow, Poland
| | - Natalia Grabska
- Department of Neurology with Unit of Stroke and Unit of Neurological Rehabilitation, The John Paul II Hospital, Krakow, Poland
| | | | - Maria Flak
- Department of Neurology, Medical University of Silesia, Faculty of Medicine, Katowice, Poland
| | - Andrzej Szczudlik
- Department of Neurology, Jagiellonian University Medical College, Krakow, Poland
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Sindou M. Is there a place for microsurgical vascular decompression of the brainstem for apparent essential blood hypertension? a review. Adv Tech Stand Neurosurg 2015; 42:69-76. [PMID: 25411145 DOI: 10.1007/978-3-319-09066-5_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
There are anatomical and physiological evidences that the ventrolateral (VL) region of the medulla plays an important role in blood pressure regulation and that dysfunction at this level may generate hypertension (HT). Vascular compression by a megadolicho-artery from the vertebrobasilar arterial system at the root entry/exit zone (REZ) of the glossopharyngeal (IXth) and vagal (Xth) cranial nerves (CNs) and the adjacent VL aspect of the medulla has been postulated as a causal factor for HT from neurogenic origin. The first attempts at microvascular decompression (MVD) of the IX-Xth CNs together with the neighbouring VL brainstem was revealed promising. These surgical attempts, as well as the numerous MRI studies, with the goal to detect and identify likely responsible neurovascular conflicts (NVC), are reviewed. Established criteria for indication of MVD as an aetiological treatment of apparent essential HT are still needed.
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Affiliation(s)
- Marc Sindou
- Department of Neurosurgery, Hopital Neurologique Pierre Wertheimer, University Lyon 1, G.H.E, 59 Boulevard Pinel, Lyon, 69003, France,
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12
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Nádas J, Czirják S, Igaz P, Vörös E, Jermendy G, Rácz K, Tóth M. [Neurovascular compression of the medulla oblongata: a rare cause of secondary hypertension]. Orv Hetil 2014; 155:838-42. [PMID: 24836320 DOI: 10.1556/oh.2014.29908] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Compression of the rostral ventrolateral medulla oblongata is one of the rarely identified causes of refractory hypertension. In patients with severe, intractable hypertension caused by neurovascular compression, neurosurgical decompression should be considered. The authors present the history of a 20-year-old man with severe hypertension. After excluding other possible causes of secondary hypertension, the underlying cause of his high blood pressure was identified by the demonstration of neurovascular compression shown by magnetic resonance angiography and an increased sympathetic activity (sinus tachycardia) during the high blood pressure episodes. Due to frequent episodes of hypertensive crises, surgical decompression was recommended, which was performed with the placement of an isograft between the brainstem and the left vertebral artery. In the first six months after the operation, the patient's blood pressure could be kept in the normal range with significantly reduced doses of antihypertensive medication. Repeat magnetic resonance angiography confirmed the cessation of brainstem compression. After six months, increased blood pressure returned periodically, but to a smaller extent and less frequently. Based on the result of magnetic resonance angiography performed 22 months after surgery, re-operation was considered. According to previous literature data long-term success can only be achieved in one third of patients after surgical decompression. In the majority of patients surgery results in a significant decrease of blood pressure, an increased efficiency of antihypertensive therapy as well as a decrease in the frequency of highly increased blood pressure episodes. Thus, a significant improvement of the patient's quality of life can be achieved. The case of this patient is an example of the latter scenario.
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Affiliation(s)
- Judit Nádas
- Bajcsy-Zsilinszky Kórház III. Belgyógyászati Oktató Osztály Budapest Maglódi út 89-91. 1106
| | | | - Péter Igaz
- Semmelweis Egyetem, Általános Orvostudományi Kar II. Belgyógyászati Klinika Budapest
| | - Erika Vörös
- Szegedi Tudományegyetem, Általános Orvostudományi Kar Radiológiai Klinika Szeged
| | - György Jermendy
- Bajcsy-Zsilinszky Kórház III. Belgyógyászati Oktató Osztály Budapest Maglódi út 89-91. 1106
| | - Károly Rácz
- Semmelweis Egyetem, Általános Orvostudományi Kar II. Belgyógyászati Klinika Budapest
| | - Miklós Tóth
- Semmelweis Egyetem, Általános Orvostudományi Kar II. Belgyógyászati Klinika Budapest
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13
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Barley J, Ellis C. Microvascular decompression: a surgical option for refractory hypertension of neurogenic etiology. Expert Rev Cardiovasc Ther 2014; 11:629-34. [DOI: 10.1586/erc.13.30] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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14
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Legrady P, Voros E, Bajcsi D, Fejes I, Barzo P, Abraham G. Observations of changes of blood pressure before and after neurosurgical decompression in hypertensive patients with different types of neurovascular compression of brain stem. Kidney Blood Press Res 2013; 37:451-7. [PMID: 24247558 DOI: 10.1159/000355725] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/05/2013] [Indexed: 11/19/2022] Open
Abstract
AIMS The neurovascular pulsatile compression of the rostral ventrolateral medulla can be divided into different subtypes. The posterior inferior cerebellar artery and/or vertebral artery can compress either the rostral ventrolateral medulla or the cranial nerves IX and X or both and on left, right or both sides. METHODS It was retrospectively investigated whether the types of neurovascular compression can influence blood pressure values. Data from 13 resistant hypertensive patients after decompression were investigated. RESULTS Six patients had 2 compressions, two had only medulla compression, four had only nerve compression on the left side and one had 2 compressions on both sides. There was no correlation between the types of compression and the levels of blood pressure, either before or after the decompression. Both, systolic and diastolic blood pressures and pulse pressure also decreased in all cases after the decompression but the change was significant only in the group with 2 compressions on the left side. CONCLUSION According to our data, in a severe hypertension not responding to conventional antihypertensive therapy, the surgical decompression of the brain stem independently of the types of neurovascular compression could guarantee a decrease of blood pressure and improved sensitivity to antihypertensive medication.
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Affiliation(s)
- Peter Legrady
- First Department of Medicine, University of Szeged, Hungary
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15
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Sandell T, Holmen J, Eide PK. Hypertension in patients with cranial nerve vascular compression syndromes and comparison with a population-based cohort. J Neurosurg 2013; 119:1302-8. [PMID: 23991839 DOI: 10.3171/2013.7.jns13231] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Although essential arterial hypertension (AH) represents a major health issue, its underlying causes remain unknown. An intriguing hypothesis is that AH in some cases may be caused by vascular compression of the rostral ventrolateral medulla (RVLM). Because hemifacial spasms (HFSs) are caused by vascular compression of the seventh cranial nerve in close proximity to the RVLM, one would, if this hypothesis is correct, expect to find a positive association between the occurrence of AH and chronic HFSs. Such a positive association would not be expected in patients with trigeminal neuralgia (TN), since TN is caused by vascular compression of the fifth cranial nerve, which is not close to the RVLM. METHODS In view of this background, the authors conducted a retrospective population-based study to investigate how the occurrence of AH in patients with either HFSs or TN compares with the prevalence of AH in the general population, when adjusted for sex and age. The general population was represented by participants of the Nord-Trøndelag Health Study 3 (HUNT3). RESULTS The prevalence of AH in the authors' patients with HFSs was significantly higher than in a sex- and age-adjusted sample from the general population; this was not true for the patients with TN. CONCLUSIONS The authors suggest that the data provide supporting evidence to the theory that compression of the RVLM may be one cause of AH.
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Affiliation(s)
- Tiril Sandell
- Department of Neurosurgery, Oslo University Hospital-Rikshospitalet
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16
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Patel S, Krishna V, Nicholas J, Welzig CM, Vera C. Preliminary observations on the vasomotor responses to electrical stimulation of the ventrolateral surface of the human medulla. J Neurosurg 2012; 117:150-5. [DOI: 10.3171/2012.3.jns11973] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Pulsatile arterial compression (AC) of the ventrolateral medulla (VLM) is hypothesized to produce the hypertension in a subset of patients with essential hypertension. In animals, a network of subpial neuronal aggregates in the VLM has been shown to control cardiovascular functions. Although histochemically similar, neurons have been identified in the retro-olivary sulcus (ROS) of the human VLM, but their function is unclear.
Methods
The authors recorded cardiovascular responses to electrical stimulation at various locations along the VLM surface, including the ROS, in patients who were undergoing posterior fossa surgery for trigeminal neuralgia. This vasomotor mapping of the medullary surface was performed using a bipolar electrode, with stimulation parameters ranging from 5- to 30-second trains (20–100 Hz), constant current (1.5–5 mA), and 0.1-msec pulse durations. Heart rate (HR) and blood pressure (BP) were recorded continuously from baseline (10 seconds before the stimulus) up to 1 minute poststimulus. In 6 patients, 17 stimulation responses in BP and HR were recorded.
Results
The frequency threshold for any cardiovascular response was 20 Hz; the stimulation intensity threshold ranged from 1.5 to 3 mA. In the first patient, all stimulation responses were significantly different from sham recordings (which consisted of electrodes placed without stimulations). Repeated stimulations in the lower ROS produced similar responses in 3 other patients. Two additional patients had similar responses to single stimulations in the lower ROS. Olive stimulation produced no response (control). Hypotensive and/or bradycardic responses were consistently followed by a reflex hypertensive response. Slight right/left differences were noted. No patient suffered short- or long-term effects from this stimulation.
Conclusions
This stimulation technique for vasomotor mapping of the human VLM was safe and reproducible. Neuronal aggregates near the surface of the human ROS may be important in cardiovascular regulation. This method of vasomotor mapping with measures of responses in sympathetic tone (microneurography) should yield additional data for understanding the neuronal network that controls cardiovascular functions in the human VLM. Further studies in which a concentric bipolar electrode is used to generate this type of vasomotor map should also increase understanding of the pathophysiological mechanisms of neurogenically mediated hypertension, and assist in the design of studies to prove the hypothesis that it is caused by pulsatile AC of the VLM.
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Affiliation(s)
- Sunil Patel
- 1Division of Neurosurgery, Department of Neuroscience; and
| | - Vibhor Krishna
- 1Division of Neurosurgery, Department of Neuroscience; and
| | - Joyce Nicholas
- 1Division of Neurosurgery, Department of Neuroscience; and
- 2Division of Biostatistics and Epidemiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | | | - Cristian Vera
- 1Division of Neurosurgery, Department of Neuroscience; and
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17
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Boogaarts HD, Menovsky T, de Vries J, Verbeek ALM, Lenders JW, Grotenhuis JA. Primary hypertension and neurovascular compression: a meta-analysis of magnetic resonance imaging studies. J Neurosurg 2012; 116:147-56. [DOI: 10.3171/2011.7.jns101378] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Several studies have suggested that neurovascular compression (NVC) of the brainstem might be a cause of hypertension. Because this compression syndrome might be demonstrated by MR imaging studies, several authors have tried to assess its prevalence in small series of patients with hypertension. This article presents a meta-analysis of these studies.
Methods
The studies reviewed by the authors were based on MR imaging and included the presence of left-sided NVC of the left rostral ventrolateral medulla oblongata (RVLM) and/or the cranial nerves IX and X root entry zone in patients with apparent primary hypertension compared with normotensive patients. Several studies also included patients with secondary hypertension as an additional control group, which is analyzed separately.
Results
Meta-analysis included data from 14 studies (597 patients with primary hypertension and 609 controls). The effect size was OR 2.68 (95% CI 1.51–4.75, p = 0.001) (random effect), which is consistent with the hypothesis that NVC of the left RVLM is more frequent in patients with apparent primary hypertension compared with normotensive individuals. Stratification for the study design revealed an effect size for prospective studies of OR 1.97 (95% CI 0.74–5.30, p = 0.178) and for retrospective studies of OR 3.36 (95% CI 1.66–6.79, p = 0.001).
Conclusions
This meta-analysis indicates a statistically significant effect size for left-sided NVC in apparent primary hypertension. However, this effect is absent if subanalysis is confined to prospective studies.
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Affiliation(s)
| | - Tomas Menovsky
- 2Department of Neurosurgery, University Hospital Antwerp, Belgium
| | | | | | - Jacques W. Lenders
- 4General Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands; and
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18
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Sakuma T, Morimoto S, Aota Y, Takahashi N, Toyoda N, Kosaki A, Maehara M, Tanigawa N, Ikeda K, Sawada S, Iwasaka T. Efficacy of clonidine in patients with essential hypertension with neurovascular contact of the rostral ventrolateral medulla. Hypertens Res 2010; 33:633-7. [DOI: 10.1038/hr.2010.41] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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19
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Conclusion. Neurosurgery 2010. [DOI: 10.1007/978-3-540-79565-0_27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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20
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Saberi H, Meybodi AT, Zeinalizadeh M. Normalization of systemic arterial hypertension following removal of posterior fossa hemangioblastoma: a case report. CASES JOURNAL 2009. [PMID: 20181189 PMCID: PMC2827080 DOI: 10.1186/1757-1626-2-7106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The concept of compression of the rostral ventrolateral medulla as a cause for hypertension is gaining more and more interest. This report is about a 36-year-old male with a three years history of hypertension who presented with a posterior fossa mass suggestive of a hemangioblastoma. Laboratory and imaging studies ruled out the presence of von Hippel-Lindau disease and/or concomitant pheochromocytoma. Post-surgical blood pressure monitoring revealed a 40 mmHg decline in blood pressure. It could be hypothesized that alleviation the compressive effect of the tumour on the rostral ventrolateral medulla as proposed by previous studies could be a contributing factor.
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21
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Efficacy of an L- and N-type calcium channel blocker in hypertensive patients with neurovascular compression of the rostral ventrolateral medulla. Hypertens Res 2009; 32:700-5. [DOI: 10.1038/hr.2009.80] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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22
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Saberi H, Meybodi AT, Zeinalizadeh M. Normalization of systemic arterial hypertension following removal of posterior fossa hemangioblastoma: a case report. CASES JOURNAL 2009; 2:7106. [PMID: 20181189 PMCID: PMC2827080 DOI: 10.1186/1757-1626-0002-0000007106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Accepted: 02/19/2009] [Indexed: 05/28/2023]
Abstract
The concept of compression of the rostral ventrolateral medulla as a cause for hypertension is gaining more and more interest. This report is about a 36-year-old male with a three years history of hypertension who presented with a posterior fossa mass suggestive of a hemangioblastoma. Laboratory and imaging studies ruled out the presence of von Hippel-Lindau disease and/or concomitant pheochromocytoma. Post-surgical blood pressure monitoring revealed a 40 mmHg decline in blood pressure. It could be hypothesized that alleviation the compressive effect of the tumour on the rostral ventrolateral medulla as proposed by previous studies could be a contributing factor.
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Affiliation(s)
- Hooshang Saberi
- Departement of Neurosurgery, Brain and Spinal Injuries Repair Research Center (BASIR), Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, 14197, Iran
| | - Ali Tayebi Meybodi
- Departement of Neurosurgery, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, 14197, Iran
| | - Mehdi Zeinalizadeh
- Departement of Neurosurgery, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, 14197, Iran
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23
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Keravel Y, Sindou M. [Vascular decompression as treatment of essential arterial hypertension]. Neurochirurgie 2009; 55:279-81. [PMID: 19328498 DOI: 10.1016/j.neuchi.2009.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Accepted: 02/12/2009] [Indexed: 10/21/2022]
Abstract
MVD of the left rostral ventrolateral medulla oblongata may be an effective treatment for patients suffering from intractable severe systemic blood hypertension. This article presents a literature review. Further clinical controlled studies have to be conducted to define precise indications.
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Affiliation(s)
- Y Keravel
- Service de neurochirurgie, hôpital Henri-Mondor, 94010 Créteil cedex, France.
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24
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Frank H, Heusser K, Geiger H, Fahlbusch R, Naraghi R, Schobel HP. Temporary Reduction of Blood Pressure and Sympathetic Nerve Activity in Hypertensive Patients After Microvascular Decompression. Stroke 2009; 40:47-51. [DOI: 10.1161/strokeaha.108.518670] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose—
Experimental studies suggested neurovascular compression of the brain stem as a cause of hypertension. The aim of our prospective study was to investigate the effect of microvascular decompression in patients with severe hypertension with neurovascular compression on blood pressure and central sympathetic nerve activity in the long-term.
Methods—
Fourteen patients (4 males; mean age, 46±8 years) with essential hypertension underwent microvascular decompression of the brain stem. Vasoconstrictor muscle sympathetic nerve activity (recorded by microneurography: burst frequency, bursts/min) and blood pressure (24-hour profiles) were investigated before surgery and 7 days, 3 months, and every 6 months postoperatively.
Results—
Muscle sympathetic nerve activity was preoperatively elevated and decreased significantly postoperatively (35±13 bursts/min vs 20±9 bursts/min;
P
<0.01). Sympathetic activity remained reduced 3 months (19±8bursts/min;
P
<0.01), 6 months (19±7 bursts/min;
P
<0.01), and 12 months (23±9 bursts/min;
P
<0.01) postoperatively. However, in the long-term, sympathetic nerve activity increased again (18 months after surgery: 28±10 bursts, not significant; 24 months postoperatively: 34±12 bursts/min, not significant). Systolic and diastolic blood pressure decreased from 162±6/98±5 mm Hg preoperatively to 133±6/85±4 mm Hg (7 days postoperatively;
P
<0.01); 136±5/86±4 mm Hg (3 months postoperatively;
P
<0.01); 132±4/85±4 mm Hg (6 months postoperatively;
P
<0.01); 132±3/85±5 mm Hg (12 months postoperatively;
P
<0.01); 132±5/84±5 mm Hg;
P
<0.01). Twenty-four months after microvascular decompression, blood pressure increased again up to 158±7/96±6 mm Hg, corresponding to the sympathetic nerve activity course.
Conclusion—
Sympathetic nerve activity and blood pressure are temporary reduced by microvascular decompression in patients with severe hypertension with neurovascular compression. The data are a hint for sympathetic overactivity as a pathomechanism in this subgroup of patients.
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Affiliation(s)
- Helga Frank
- From Department of Nephrology (H.F.), Klinikum rechts der Isar, Technische Universitaet Muenchen, Germany; Department of Clinical Pharmacology (K.H.), Hannover Medical School, Hannover, Germany; Department of Nephrology (H.G.), University of Frankfurt, Germany; International Neuroscience Institute Hannover (R.F.), Germany; Department of Neurosurgery (R.N.), University of Erlangen-Nuremberg, Germany; Benedictus Krankenhaus Tutzing (H.P.S.), Germany
| | - Karsten Heusser
- From Department of Nephrology (H.F.), Klinikum rechts der Isar, Technische Universitaet Muenchen, Germany; Department of Clinical Pharmacology (K.H.), Hannover Medical School, Hannover, Germany; Department of Nephrology (H.G.), University of Frankfurt, Germany; International Neuroscience Institute Hannover (R.F.), Germany; Department of Neurosurgery (R.N.), University of Erlangen-Nuremberg, Germany; Benedictus Krankenhaus Tutzing (H.P.S.), Germany
| | - Helmut Geiger
- From Department of Nephrology (H.F.), Klinikum rechts der Isar, Technische Universitaet Muenchen, Germany; Department of Clinical Pharmacology (K.H.), Hannover Medical School, Hannover, Germany; Department of Nephrology (H.G.), University of Frankfurt, Germany; International Neuroscience Institute Hannover (R.F.), Germany; Department of Neurosurgery (R.N.), University of Erlangen-Nuremberg, Germany; Benedictus Krankenhaus Tutzing (H.P.S.), Germany
| | - Rudolf Fahlbusch
- From Department of Nephrology (H.F.), Klinikum rechts der Isar, Technische Universitaet Muenchen, Germany; Department of Clinical Pharmacology (K.H.), Hannover Medical School, Hannover, Germany; Department of Nephrology (H.G.), University of Frankfurt, Germany; International Neuroscience Institute Hannover (R.F.), Germany; Department of Neurosurgery (R.N.), University of Erlangen-Nuremberg, Germany; Benedictus Krankenhaus Tutzing (H.P.S.), Germany
| | - Ramin Naraghi
- From Department of Nephrology (H.F.), Klinikum rechts der Isar, Technische Universitaet Muenchen, Germany; Department of Clinical Pharmacology (K.H.), Hannover Medical School, Hannover, Germany; Department of Nephrology (H.G.), University of Frankfurt, Germany; International Neuroscience Institute Hannover (R.F.), Germany; Department of Neurosurgery (R.N.), University of Erlangen-Nuremberg, Germany; Benedictus Krankenhaus Tutzing (H.P.S.), Germany
| | - Hans P. Schobel
- From Department of Nephrology (H.F.), Klinikum rechts der Isar, Technische Universitaet Muenchen, Germany; Department of Clinical Pharmacology (K.H.), Hannover Medical School, Hannover, Germany; Department of Nephrology (H.G.), University of Frankfurt, Germany; International Neuroscience Institute Hannover (R.F.), Germany; Department of Neurosurgery (R.N.), University of Erlangen-Nuremberg, Germany; Benedictus Krankenhaus Tutzing (H.P.S.), Germany
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25
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Grassi G. Blood pressure lowering effects of non-surgical procedures for vascular decompression: good news to be taken with caution. J Hum Hypertens 2007; 21:341-2. [PMID: 17252031 DOI: 10.1038/sj.jhh.1002134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- G Grassi
- Clinica Medica, Dipartimento di Medicina Clinica, Prevenzione e Biotecnologie Sanitarie, Università Milano-Bicocca, Ospedale San Gerardo, Monza (Milan), Italy.
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26
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Pickering TG. Neurovascular Compression of the Medulla: Can It Cause Neurogenic Hypertension? J Clin Hypertens (Greenwich) 2007; 9:63-6. [PMID: 17215662 PMCID: PMC8109868 DOI: 10.1111/j.1524-6175.2007.05980.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Thomas G Pickering
- Behavioral Cardiovascular Health and Hypertension Program, Columbia Presbyterian Medical Center, New York, NY 10032, USA.
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27
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Autonomic neurosurgery: from microvascular decompression to image guided stimulation. Biomed Imaging Interv J 2007; 3:e14. [PMID: 21614256 PMCID: PMC3097652 DOI: 10.2349/biij.3.1.e14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Accepted: 01/28/2007] [Indexed: 11/17/2022] Open
Abstract
The paper reviews mechanisms underlying autonomic disorders, with a focus on cardiovascular dysfunction. Neurosurgical approaches are described for medically refractory hypertension and orthostatic hypotension. After review of microvascular decompression of the rostral ventrolateral medulla, stereotactic CT and MRI guided deep brain stimulation of the periaqueductal grey matter (PAG) is evaluated. Results are presented from patient studies showing reductions in blood pressure with ventral PAG stimulation and increases in blood pressure with dorsal PAG stimulation. A rationale for the treatment of autonomic disorders by neurosurgical intervention is discussed.
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28
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Ceral J, Zizka J, Eliás P, Solar M, Klzo L, Reissigová J. Neurovascular compression in essential hypertension: cause, consequence or unrelated finding? J Hum Hypertens 2006; 21:179-81. [PMID: 17136105 DOI: 10.1038/sj.jhh.1002124] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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29
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Dicker D, Maya I, Vasilevsky V, Gofman M, Markowitz D, Beilin V, Sarid M, Yosefy C. Blood pressure variability in acute ischemic stroke depends on hemispheric stroke location. Blood Press 2006; 15:151-6. [PMID: 16864156 DOI: 10.1080/08037050600772755] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The relationship between blood pressure (BP) variability and stroke location was examined in 85 patients admitted with acute ischemic stroke. The patients were divided into three groups according to stroke location: right hemisphere (32 patients), left hemisphere (30 patients) and non-localized (23 patients). BP upon admission was 147.94/76.53 +/- 20.72/13.70 mmHg in the right hemisphere group, 151.81/76.10 +/- 25.69/16.23 mmHg in the left hemisphere and 155.23/83.41 +/- 30.45/15.74 in the non-localized group. The left hemisphere group had significantly (p < 0.01) greater variations in systolic and diastolic BP between days 2 and 3 and in systolic BP between days 3 and 4 after stroke compared with the other groups. BP in the left hemisphere group was less stable than in the other two groups. Non-localized patients without pre-existing hypertension had a significantly lower and more stable BP during the week following stroke than non-localized patients with pre-existing hypertension. Non-localized patients with pre-existing hypertension had the highest BP and showed no improvement during the week. Systolic BP tended to be higher and less stable in left hemisphere patients than in right hemisphere, whereas among non-localized ischemic stroke patients BP was higher in those who had a prior diagnosis of hypertension.
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Affiliation(s)
- Dror Dicker
- Internal Medicine D, Rabin Medical Center, Campus Hasharon, Israel.
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30
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Kan P, Couldwell WT. Posterior fossa brain tumors and arterial hypertension. Neurosurg Rev 2006; 29:265-9; discussion 269. [PMID: 16924459 DOI: 10.1007/s10143-006-0036-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Revised: 03/16/2006] [Accepted: 04/30/2006] [Indexed: 11/29/2022]
Abstract
Hypertension caused by arterial compression of the rostral ventrolateral medulla is well described. Much less information is available on the association between neurogenic hypertension and posterior fossa brain tumors. To date, multiple reports have supported the impression that a small subpopulation of patients with posterior fossa tumors can present with arterial hypertension, and many of those patients achieved significant improvement of their hypertension after tumor resection and medullary decompression. To review the relationship between posterior fossa brain tumors and hypertension, we detail the history, basic science, and clinical reports along with an illustrative case regarding this topic.
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Affiliation(s)
- Peter Kan
- Department of Neurosurgery, University of Utah School of Medicine, 30 North 1900 East, Suite 3B409, Salt Lake City, 84132, USA
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31
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Fessel J, Robertson D. Orthostatic hypertension: when pressor reflexes overcompensate. ACTA ACUST UNITED AC 2006; 2:424-31. [PMID: 16932477 DOI: 10.1038/ncpneph0228] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2005] [Accepted: 03/31/2006] [Indexed: 11/08/2022]
Abstract
Orthostatic hypertension--a rise in blood pressure upon assuming upright posture-is an underappreciated and understudied clinical phenomenon. There is currently no widely agreed-upon definition of clinical orthostatic hypertension, the current definitions being operational within the context of particular studies. The underlying pathophysiology is thought to involve activation of the sympathetic nervous system, but the actual etiology is poorly understood. Orthostatic hypertension is observed in association with a variety of other clinical conditions, including essential hypertension, dysautonomias, and type 2 diabetes mellitus. Orthostatic hypertension has been associated with increased occurrence of silent cerebrovascular ischemia and possibly with neuropathy in type 2 diabetes. So, appreciation of the true incidence of orthostatic hypertension, elucidation of the underlying pathophysiology, and an understanding of potentially effective treatment approaches and their associated risks and benefits might all have major clinical significance. Orthostatic hypertension is an aspect of hypertension that is in need of further focused investigation.
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Affiliation(s)
- Joshua Fessel
- Department of Medicine at Vanderbilt University, Nashville, TN 37232-2195, USA
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Sendeski MM, Consolim-Colombo FM, Leite CC, Rubira MC, Lessa P, Krieger EM. Increased sympathetic nerve activity correlates with neurovascular compression at the rostral ventrolateral medulla. Hypertension 2006; 47:988-95. [PMID: 16567595 DOI: 10.1161/01.hyp.0000214403.07762.47] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We used microneurography to measure muscle sympathetic nerve activity (MSNA) in 25 hypertensive subjects and correlated these results with the presence or absence of signs of neurovascular compression (NVC) at the rostral ventrolateral (RVL) medulla on MRI. Subjects were divided into 3 groups based on MRI findings: NVC-, no MRI evidence of NVC (N=9); NVC+contact, image showing artery in contact but not compressing the RVL medulla (N=8); and NVC+compression, image showing arterial compression of the RVL medulla (N=8). The MSNA measurements were performed at rest, after a hypothermic stimulus, and during isometric exercise. The MSNA during rest in the NVC+compression group was significantly higher than that in the NVC+contact and NVC- groups (30.4+/-3.4 versus 17.5+/-1.1 and 21.4+/-3.2 spikes per minute, respectively). However, the blood pressure in the NVC+compression group was slightly but not significantly higher than that in the other 2 groups (183+/-7/115+/-8, 174+/-6/108+/-7, and 171+/-5/110+/-5 mm Hg, respectively). The increases in MSNA, blood pressure, and heart rate during the cold pressor and isometric exercise tests were similar. Our results show that, although resting MSNA is elevated in patients with true NVC of the RVL medulla, patients without NVC or with arterial contact but not overt compression of the RVL medulla have similar MSNA. These findings are important for identifying, among hypertensive patients with NVC, individuals who may have associated physiological repercussions, such as increased sympathetic activity.
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Sendeski MM, Consolim-Colombo FM, Krieger EM, Leite CDC. The spectrum of magnetic resonance imaging findings in hypertension-related neurovascular compression. Neuroradiology 2005; 48:21-5. [PMID: 16331449 DOI: 10.1007/s00234-005-0005-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2004] [Accepted: 07/04/2005] [Indexed: 10/25/2022]
Abstract
Hypertension (HTN) has been controversially related to neurovascular compression (NVC) at the rostral ventrolateral (RVL) medulla in anatomical, surgical, and radiological reports. Our objective was to investigate the association between primary HTN and signs of NVC at the medulla oblongata on magnetic resonance imaging (MRI) and to explore a new classification based on image criteria. Subjects with (n=64) and without (n=29) HTN were studied. Three-millimeter slices, with 1-mm intervals in between, were performed on T2-weighted images in axial and coronal views. Attention was focused on the relationship between the upper medulla and the surrounding arteries. The findings were divided into three categories: 1) non-NVC: absence of signs of NVC, 2) NVC type I: an artery in contact with the RVL medulla but not compressing it, and 3) NVC type II: evident compression of the RVL medulla by an artery. Signs of NVC were observed in 65.7% (42/64) of the HTN group (type I: 39.1%, 25/42 patients; type II: 26.6%, 17/42 patients). Among the normotensive subjects, 27.6% (8/29) had signs of NVC; only one (3.3%) of these had NVC type II (evident compression), and the rest were NVC type I. We conclude that the presence of NVC at the RVL medulla on MRI is related to HTN. More importantly, the finding of frank compression (NVC type II) is present almost exclusively in hypertensive subjects; only one individual (3.3% of our normotensive population) had NVC type II.
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Affiliation(s)
- Mauricio Michalak Sendeski
- Heart Institute (InCor) and Discipline of Neurosurgery, University of São Paulo Medical School, São Paulo, Brazil
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Coffee RE, Nicholas JS, Egan BM, Rumboldt Z, D'Agostino S, Patel SJ. Arterial compression of the retro-olivary sulcus of the medulla in essential hypertension: a multivariate analysis. J Hypertens 2005; 23:2027-31. [PMID: 16208145 DOI: 10.1097/01.hjh.0000187256.02072.41] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Pulsatile arterial compression (AC) of the ventrolateral medulla (VLM) has been postulated to cause neurogenically mediated essential hypertension (EHTN). We aimed to establish whether the association between AC of specifically the retro-olivary sulcus (ROS) of the VLM and EHTN was significant, while controlling for other risks associated with EHTN. DESIGN Case-control study. METHODS Posterior fossa magnetic resonance imaging scans of 131 subjects, including 58 subjects with EHTN and 73 normotensives, were reviewed to determine the presence of AC in the ROS. The history of other risk factors for EHTN was obtained by reviewing medical records. RESULTS Multivariate logistic regression analysis of these data shows a significant association between AC in the ROS (right and/or left) and EHTN [odds ratio (OR) = 3.03, 95% confidence interval (CI) = 1.30, 7.06]. This analysis was done controlling for other known EHTN risk factors such as age, race, sex, diabetes, and obesity. A secondary analysis also controlling for these variables shows that AC of both the right and left ROS are independently associated with EHTN (right AC: OR = 5.04, 95% CI = 1.33, 19.17; left AC: OR = 3.39, 95% CI = 1.20, 9.60). CONCLUSIONS In this retrospective study of subjects with EHTN and normotensive controls that had undergone magnetic resonance imaging of the posterior fossa, AC of the ROS on either side of the medulla is a significant independent risk factor in EHTN. Further studies are required to determine whether this is true for the general population of patients with neurogenically mediated EHTN.
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Affiliation(s)
- Robert E Coffee
- College of Medicine, Medical University of South Carolina, Charleston, 29425, USA
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Naderi S, Acar F, Acar G, Men S. Resolution of neurogenic arterial hypertension after suboccipital decompression for Chiari malformation. Case report. J Neurosurg 2005; 102:1147-50. [PMID: 16028778 DOI: 10.3171/jns.2005.102.6.1147] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A Chiari malformation Type I may remain asymptomatic until the patient has reached adulthood and acute presentation of symptoms occurs. In several clinical and experimental studies it has been shown that essential hypertension is associated with vascular compression of the brainstem, particularly of the rostral ventrolateral medulla oblongata. Nevertheless, two cases of Chiari malformation and neurogenic arterial hypertension have been reported. In this article the authors describe a patient with Chiari malformation Type I and neurogenic arterial hypertension. A simple suboccipital decompression not only provided neurological improvement, but also led to resolution of the hypertension. In cases of Chiari malformation and concomitant neurogenic arterial hypertension, careful preoperative clinical and neuroimaging assessments may reveal the cause of the arterial hypertension. Resolution of neurogenic arterial hypertension may be expected even in a case of simple suboccipital decompression.
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Affiliation(s)
- Sait Naderi
- Department of Neurosurgery, Faculty of Medicine, Dokuz Eylul University, Inciralti, Izmir, Turkey.
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Tomasello F, Alafaci C, Salpietro FM, Longo M. Bulbar Compression by an Ectatic Vertebral Artery: A Novel Neurovascular Construct Relieved by Microsurgical Decompression. Oper Neurosurg (Hagerstown) 2005; 56:117-24; discussion 117-24. [PMID: 15799799 DOI: 10.1227/01.neu.0000146684.23593.b4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2004] [Accepted: 09/23/2004] [Indexed: 11/19/2022] Open
Abstract
Abstract
OBJECTIVE:
Brainstem compression caused by vascular abnormalities has rarely been reported in the literature. We describe five cases of large ectatic vertebral artery causing compression and distortion of the medulla oblongata with pyramidal tract signs and low cranial nerve dysfunction. Microvascular decompression by retracting the vertebral artery and anchoring it to the dura has been the treatment of choice.
METHODS:
Five patients, four male and one female, presented with progressive myelopathic features and lower cranial nerve dysfunction, especially dysphonia and dysphagia. Four patients were affected by systemic arterial hypertension. Magnetic resonance imaging showed impingement of the right vertebral artery in three patients and the left vertebral artery in two patients, on the right and left lateral medulla, respectively. In two patients, hypoplasia of the contralateral vertebral artery was documented.
RESULTS:
All patients underwent neurovascular decompression of the medulla oblongata. The ectatic and tortuous vertebral artery was detached from the medulla, shifted away, and repositioned by anchoring to the nearby dura mater using a Gore-Tex vascular slip. Postoperatively, all patients but one had improvement of their previous neurological symptoms.
CONCLUSION:
Brainstem dysfunction caused by a tortuous ectatic vertebral artery might be less uncommon than expected. It should be considered a new distinct clinical entity, the real incidence of which needs to be carefully evaluated by an appropriate diagnostic protocol, which includes primarily magnetic resonance imaging with specific three-dimensional sequences. Awareness of this condition is necessary to ensure the appropriate treatment. Surgical microvascular decompression seems very effective.
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Jannetta PJ, Hollihan L. Type 2 diabetes mellitus, etiology and possible treatment: preliminary report. ACTA ACUST UNITED AC 2004; 61:422-6; discussion 426-8. [PMID: 15120209 DOI: 10.1016/j.surneu.2003.08.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2002] [Accepted: 08/26/2003] [Indexed: 10/26/2022]
Abstract
BACKGROUND Insulin resistance has been proposed as the initial step in the cascade toward type 2 diabetes mellitus. The mechanisms underlying the development of insulin resistance are not fully understood. We hypothesize that neurovascular interactions, in particular arterial elongation, causes compression of the right lateral medulla, triggering a state of autonomic dysfunction including hyperactivity of pancreatic endocrine function, and predisposes to insulin resistance and the development of type 2 diabetes. METHODS The clinical and operative findings were reviewed retrospectively in 15 patients with primary diagnoses of various right-sided cranial rhizopathies, but with a common diagnosis of type 2 diabetes mellitus. After microvascular decompression was performed for the primary diagnosis, arterial compression was observed of the lateral medulla and cranial nerve X and treated with microvascular decompression. Known duration of the diabetes ranged from "new" (patient was diagnosed as a result of preoperative blood work) to 16 years (mean 7.3 years). Duration of diabetes diagnosis was unknown in 2 patients. Follow-up was from 3 to 113 months (mean 29.9 months). RESULTS Ten of the 15 patients (66%) showed improvement in their blood glucose control; 5 of those 10 (50%) did so with no (4 patients) or less (1 patient) diabetes medication. CONCLUSIONS We have shown that arterial compression of the right lateral medulla is consistently present in patients with diabetes mellitus and that microvascular decompression can be performed safely. Further studies are necessary and are under way.
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Affiliation(s)
- Peter J Jannetta
- Department of Neurosurgery, Allegheny General Hospital, Pittsburgh, Pennsylvania 15212, USA
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Zizka J, Ceral J, Elias P, Tintera J, Klzo L, Solar M, Straka L. Vascular Compression of Rostral Medulla Oblongata: Prospective MR Imaging Study in Hypertensive and Normotensive Subjects. Radiology 2004; 230:65-9. [PMID: 14631051 DOI: 10.1148/radiol.2301021285] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To prospectively evaluate prevalence of neurovascular contacts (NVCs) at the rostral medulla oblongata in normotensive and hypertensive subjects. MATERIALS AND METHODS Forty-three patients with severe essential hypertension and 45 normotensive subjects were matched for age, sex, and body mass index. Magnetic resonance (MR) imaging included transverse and coronal T2-weighted turbo spin-echo (section thickness, 3.0 mm), transverse three-dimensional (3D) time-of-flight MR angiographic (section thickness, 0.8 mm), and 3D constructive interference in steady state (CISS) (section thickness, 1.0 mm) sequences. All MR images were reviewed by two radiologists who were blinded to the hypertensive status of subjects. Presence and degree of NVC at rostral medulla and left/right rostral ventrolateral medulla (RVLM) were evaluated together with conspicuity of anatomic structures on MR images. Differences in prevalence of NVC among normotensive and hypertensive subjects were tested for statistical significance (P <.05) by using nonparametric tests. RESULTS Among hypertensive patients, 34 (79%) of 43 showed NVC of rostral medulla at any location, and 14 (33%) of 43 had NVC at the left RVLM. In controls (normotensive subjects), 35 (78%) of 45 showed NVC of rostral medulla, and 17 (38%) of 45 had NVC at left RVLM. Prevalence of NVC was not significantly different between both groups at any location of rostral medulla. Compared with T2-weighted turbo spin-echo and 3D time-of-flight MR imaging sequences, 3D CISS offered better contrast resolution of neural and vascular structures and superior delineation of outer vascular contours. CONCLUSION Vascular compression of the rostral medulla oblongata is a frequent finding in both hypertensive and normotensive subjects. Results of this study do not support NVC at left RVLM as an etiologic factor in essential hypertension.
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Affiliation(s)
- Jan Zizka
- Departments of Radiology and Internal Medicine, Charles University Hospital, Sokolská 581, CZ-500 05 Hradec Králové, Czech Republic.
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Plaugher G, Long CR, Alcantara J, Silveus AD, Wood H, Lotun K, Menke JM, Meeker WC, Rowe SH. Practice-based randomized controlled-comparison clinical trial of chiropractic adjustments and brief massage treatment at sites of subluxation in subjects with essential hypertension: pilot study. J Manipulative Physiol Ther 2002; 25:221-39. [PMID: 12021741 DOI: 10.1067/mmt.2002.123171] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To determine the feasibility of conducting a randomized clinical trial in the private practice setting examining short- and long-term effects of chiropractic adjustments for subjects with essential hypertension compared with a brief soft tissue massage, as well as a nontreatment control group. DESIGN Randomized controlled-comparison trial with 3 parallel groups. SETTING Private practice outpatient chiropractic clinic. PATIENTS Twenty-three subjects, aged 24 to 50 years with systolic or diastolic essential hypertension. INTERVENTIONS Two months of full-spine chiropractic care (ie, Gonstead) consisting primarily of specific-contact, short-lever-arm adjustments delivered at motion segments exhibiting signs of subluxation. The massage group had a brief effleurage procedure delivered at localized regions of the spine believed to be exhibiting signs of subluxation. The nontreatment control group rested alone for a period of approximately 5 minutes in an adjustment room. MAIN OUTCOME MEASURES Cost per enrolled subject, as well as systolic and diastolic blood pressure (BP) measured with a random-0 sphygmomanometer and patient reported health status (SF-36). Pilot study outcome measures also included an assessment of cooperation of subjects to randomization procedures and drop-out rates, recruitment effectiveness, analysis of temporal stability of BPs at the beginning of care, and the effects of inclusion/exclusion criteria on the subject pool. RESULTS Thirty subjects enrolled, yielding a cost of $161 per enrolled subject. One subject was later determined to be ineligible, and 6 others dropped out. In both the chiropractic and massage therapy groups, all subjects were classified as either overweight or obese; in the control group there were only 2 classified as such. SF-36 profiles for the groups were similar to that of a normal population. The mean change in diastolic BP was -4 (95% confidence interval [CI]: -8.6, 0.5) in the chiropractic care group, 0.5 (95% CI: -3.5, 4.5) in the brief massage treatment group, and -4.9 (95% CI: -9.7, -0.1) in the no treatment control group. At the end of the study period, this change was -6.3 (95% CI: 13.1, 0.4), -1.0 (95% CI: -7.5, 15.6), -7.2 (95% CI: -13.3, -1.1) in the 3 study groups. The mean improvements in the chiropractic care and no treatment control groups remained consistent over the follow-up period. CONCLUSIONS This pilot study elucidated several procedural issues that should be addressed before undertaking a full-scale clinical trial on the effects of chiropractic adjustments in patients with essential hypertension. A multidisciplinary approach to recruitment may need to be used in any future efforts because of the limited subject pool of patients who have hypertensive disease but are not taking medications for its control. Measures need to be used to assure comparable groups regarding prognostic variables such as weight. Studies such as these demonstrate the feasibility of conducting a full-scale 3-group randomized clinical trial in the private practice setting.
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Affiliation(s)
- Gregory Plaugher
- Director of Research, Life Chiropractic College West, 25001 Industrial Boulevard, Hayward, CA 94545, USA
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Ratanakorn D, Yunis C, Ferrario CM, McKinney WM. Noninvasive ultrasound evaluation of the vertebral artery in hypertension. J Neuroimaging 2002; 12:158-63. [PMID: 11977912 DOI: 10.1111/j.1552-6569.2002.tb00114.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Surgical decompression of the vascular loop of the vertebral artery (VA) at the left lateral medulla can reduce blood pressure (BP) in hypertension, and a larger diameter of the left VA has been found in hypertensive patients. Noninvasive evaluation of the VA in hypertension may assist selecting patients for more appropriate diagnosis and treatment. Duplex ultrasonography is used to study the relationship between VA diameter and BP. METHODS A retrospective review of VA duplex ultrasonography was performed in 112 consecutive patients who were sent to the neurovascular laboratory at the Wake Forest University School of Medicine during a 2-month period. All measurements (BP, pulse rate, peak systolic velocity [PSV], end diastolic velocity [EDV], and diameters of both VAs) were determined according to standardized protocols. Left-right comparisons of VA diameters, PSV, and EDV between hypertensives and normotensives were performed by the matched-pairs analysis techniques. RESULTS Fifty-five women and 57 men with a mean age of 64.8 years were studied. Hypertension was present in 65.2% of all patients. The age-adjusted mean left VA diameter was significantly higher than that of the right VA with an age-adjusted average differences of 0.2 mm (P = .03) for hypertensives compared to 0.04 mm (P = .75) for normotensives. No significant differences were observed in either PSV or EDV. CONCLUSIONS Differences in left-right VA diameter in hypertensive subjects may be a previously unrecognized component of the vascular disturbances associated with the disease and represent an additional criterion for identifying those who may benefit from surgical and medical management.
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Affiliation(s)
- Disya Ratanakorn
- Division of Neurology, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama 6 Road, Rajathevee, Bangkok 10400, Thailand.
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Hohenbleicher H, Schmitz SA, Koennecke HC, Offermann J, Offermann R, Wolf KJ, Distler A, Sharma AM. Neurovascular contact and blood pressure response in young, healthy, normotensive men. Am J Hypertens 2002; 15:119-24. [PMID: 11863246 DOI: 10.1016/s0895-7061(01)02288-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
BACKGROUND Neurovascular contact (NVC) of the left rostral ventrolateral medulla has been implicated in the pathogenesis of "essential" hypertension, and recent studies suggest that this anomaly may be genetically determined. We therefore assessed the prevalence of this vascular anomaly in young normotensive volunteers. We also studied blood pressure, heart rate reactivity, and changes in baroreflex sensitivity in response to mental and physical stress in a subset of subjects with positive and negative brainstem findings. METHODS Magnetic resonance imaging of the brainstem was performed in 113 young (aged 25 +/- 8 years), normotensive male volunteers. Baroreflex sensitivity was then assessed in 13 subjects with positive brainstem findings and 20 subjects with negative findings. RESULTS Left-sided NVC was found in 19 subjects. Blood pressure levels, heart rate, and baroreflex sensitivity were similar in all groups. However, modulation of baroreflex sensitivity was reduced under mental and physical stress in subjects with a positive finding for NVC. Subjects with a positive finding also had a significantly lower body mass index than those with a negative finding. CONCLUSIONS Left-sided NVC is present in approximately one-fifth of young normotensive men, and may modulate the baroreceptor reflex under stress in these individuals.
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Affiliation(s)
- Henriette Hohenbleicher
- Department of Internal Medicine, Division of Endocrinology and Nephrology, Universitätsklinikum Benjamin Franklin, Berlin, Germany
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Frank H, Schobel HP, Heusser K, Geiger H, Fahlbusch R, Naraghi R. Long-term results after microvascular decompression in essential hypertension. Stroke 2001; 32:2950-5. [PMID: 11740004 DOI: 10.1161/hs1201.099799] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE In 1998, 8 patients with severe, intractable arterial hypertension and MR tomography-demonstrated neurovascular contact of a looping artery at the root entry zone of cranial nerves IX and X, causing neurovascular compression, underwent neurosurgical decompression. The short-term results showed a normalization of blood pressure with a markedly reduced antihypertensive drug regimen in 7 patients. To determine the longer-term outcome concerning blood pressure and secondary organ damage after neurovascular decompression, we studied these 8 operated patients prospectively for a mean follow-up of 3.5 years after surgical intervention. METHODS Eight hypertensive patients who had undergone microsurgical decompression were monitored every 6 months after surgery to assess blood pressure (by 24-hour ambulatory pressure readings) and the need for antihypertensive medication. To evaluate secondary organ damage, echocardiographic assessment of left ventricular hypertrophy, fundoscopic assessment of hypertensive lesions, and analysis of renal function and proteinuria were done. RESULTS Three of the 8 operated patients remained normotensive in the long-term period with decreased antihypertensive medication. Two patients required gradual increases of antihypertensive medication after the first postoperative year, after which arterial blood pressure levels were 10% to 15% lower than preoperative levels. Three patients suffered serious cardiovascular and renal complications, with the incidence of lethal intracerebral hemorrhage in 1 patient and end-stage renal disease in 2 patients, of whom 1 experienced sudden cardiac death. CONCLUSIONS The long-term results verify that microsurgical decompression is a successful alternative therapy in a certain subgroup of patients with arterial hypertension due to neurovascular compression. However, the relevance of the looping artery in the other cases, who did not improve, is not clear. Prospective studies to elucidate the pathophysiological role of neurovascular abnormalities and arterial hypertension are needed.
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Affiliation(s)
- H Frank
- Medical Department IV/Nephrology, Clinic of Neurosurgery, University Erlangen, and Medical Department IV/Nephrology, University Frankfurt/Main, Germany.
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Ochiai H, Yamakawa Y, Kubota E. Deformation of the ventrolateral medulla oblongata by subarachnoid hemorrhage from ruptured vertebral artery aneurysms causes neurogenic pulmonary edema. Neurol Med Chir (Tokyo) 2001; 41:529-34; discussion 534-5. [PMID: 11758704 DOI: 10.2176/nmc.41.529] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The occurrence of neurogenic pulmonary edema (NPE) associated with subarachnoid hemorrhage (SAH) due to ruptured aneurysm was analyzed in 48 consecutive patients. Correlations of the location of the aneurysm, clinical grade, amount of subarachnoid clot, and severity of NPE were examined. NPE was observed in 29.4% of all SAH cases, but the incidence was significantly higher in cases of ruptured vertebral artery (VA) aneurysm. Clinical grade, severity of NPE, and deformation of the medulla oblongata were studied in the five cases of ruptured VA aneurysm. Deformation of the ventrolateral medulla oblongata was observed in all patients. Asymmetry index of the medulla oblongata measured on the axial computed tomography scan was correlated with the severity of NPE. Severity of NPE tended to correlate with deformation of the medulla oblongata. NPE associated with ruptured VA aneurysm is caused by deformation of the ventrolateral site of the medulla oblongata by the localized hemorrhage.
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Affiliation(s)
- H Ochiai
- Department of Neurosurgery, Miyazaki Prefectural Hospital, Japan
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Naraghi R, Fahlbusch R. Microvascular decompression for the treatment of hypertension. ACTA ACUST UNITED AC 2001. [DOI: 10.1053/otns.2001.27382] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Levy EI, Scarrow AM, Jannetta PJ. Microvascular decompression in the treatment of hypertension: review and update. SURGICAL NEUROLOGY 2001; 55:2-10; discussion 10-1. [PMID: 11248294 DOI: 10.1016/s0090-3019(00)00352-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Neurogenic hypertension in association with vascular compression of the left rostral ventrolateral medulla has been documented. A recent group of these clinical reports has raised great interest in decompression of this area of the brainstem as a definitive therapy for essential hypertension. METHODS To further clarify the mechanism by which decompression of the left rostral ventrolateral medulla relieves neurogenic hypertension, we describe in detail the basic science, animal models, human studies, and most recent clinical trials regarding surgical decompression of this area. CONCLUSION Multi-disciplinary evidence supports the hypothesis that a sub-population of hypertensive patients achieve significant relief of their hypertension after microvascular decompression. A multi-institutional, prospective, randomized study is necessary to determine the efficacy of microvascular decompression for neurogenic hypertension.
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Affiliation(s)
- E I Levy
- Department of Neurosurgery, University of Pittsburgh School of Medicine, UPMC Presbyterian Hospital, 200 Lothrop Street, Suite B-400, Pittsburgh, PA 15213-2582, USA
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Hohenbleicher H, Schmitz SA, Koennecke HC, Offermann R, Offermann J, Zeytountchian H, Wolf KJ, Distler A, Sharma AM. Neurovascular Contact of Cranial Nerve IX and X Root-Entry Zone in Hypertensive Patients. Hypertension 2001; 37:176-181. [PMID: 11208774 DOI: 10.1161/01.hyp.37.1.176] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
-Neurovascular contact of the left rostral ventrolateral medulla has been implicated in the pathogenesis of "essential" hypertension, and recent intervention studies suggest that surgical decompression of the ventrolateral medulla lowers blood pressure in these patients. We assessed the prevalence of this vascular anomaly in patients with essential hypertension by using an advanced MRI technique. We performed MRI of the brain stem in 125 hypertensive patients and in 105 age-matched, sex-matched, and body mass index-matched normotensive control subjects. Imaging of the root-entry zone of cranial nerves IX and X was performed by combining a high-resolution 3D constructive interference in steady-state sequence with a flow-sensitive time-of-flight technique, and images were independently assessed by 4 readers using predefined criteria. Left-sided neurovascular contact was found in 23% of the hypertensive patients and in 16% of the normotensive individuals (P:=0.12). Blood pressure level, heart rate, and number of antihypertensive medications in treated hypertensive patients were similar among patients with positive, borderline, and negative brain stem findings. Our findings cast doubt on the importance of left-sided neurovascular contact as a frequent cause of essential hypertension or as a major factor determining the severity of hypertension in patients with this anomaly.
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Affiliation(s)
- Henriette Hohenbleicher
- Department of Internal Medicine (H.H., R.O., J.O., H.Z., A.D., A.M.S.), Division of Endocrinology and Nephrology, the Department of Radiology (S.A.S., K.-J.W.), and the Department of Neurology (H.-C.K.), Universitätsklinikum Benjamin Franklin, Berlin, Germany
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47
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Guyenet PG. Neural structures that mediate sympathoexcitation during hypoxia. RESPIRATION PHYSIOLOGY 2000; 121:147-62. [PMID: 10963771 DOI: 10.1016/s0034-5687(00)00125-0] [Citation(s) in RCA: 177] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The sympathetic adjustments triggered by acute mild hypoxia (sympathetic chemoreflex) are initiated by activation of peripheral chemoreceptors whereas more severe hypoxia activates the sympathetic outflow via direct effects on the brainstem. In both cases the rostral ventrolateral medulla (RVLM) plays a critical role in these responses. The first part of this review briefly describes the general input-output properties of the presympathetic neurons of RVLM before focusing on the neural pathways leading to their excitation in response to peripheral chemoreceptor stimulation. The extent to which the central respiratory network contributes to the sympathetic chemoreflex is then discussed before briefly alluding to its role in obstructive sleep apnea and other pathologies. The second half of the review examines the direct effects of hypoxia on RVLM neurons and whether this region and the presympathetic neurons in particular qualify as a physiological central oxygen sensor. The literature is also examined in the context of cerebral ischemia, the Cushing response and the genesis of certain forms of hypertension.
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Affiliation(s)
- P G Guyenet
- Department of Pharmacology, University of Virginia Health System, 1300 Jefferson Park Avenue, PO Box 800735, Charlottesville, VA 22908, USA.
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Gajjar D, Egan B, Curè J, Rust P, VanTassel P, Patel SJ. Vascular compression of the rostral ventrolateral medulla in sympathetic mediated essential hypertension. Hypertension 2000; 36:78-82. [PMID: 10904016 DOI: 10.1161/01.hyp.36.1.78] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The pathophysiological factors of neurogenic or sympathetically mediated essential hypertension are unknown. Neurons close to the surface of the ventrolateral medulla (specifically, in the retro-olivary sulcus [ROS]) are integrally involved in the control of blood pressure by means of efferent connections to presympathetic neurons in the spinal cord. It is hypothesized that vascular contact with the ROS is pathogenically involved in neurogenically mediated hypertension. We evaluated that theory in 20 subjects with uncomplicated stage 1 to stage 2 essential hypertension (EHTN) (18 of whom completed the study). The baseline supine plasma norepinephrine level served as an index of central sympathetic outflow. The response of blood pressure to clonidine was used as a surrogate marker for neurogenically mediated hypertension. We also examined the relationship between those markers and evidence of anatomic abnormalities in the area of the ROS that was provided by magnetic resonance imaging. A vessel contacted the left ROS in 5 of the 18 subjects. Those 5 subjects had higher plasma norepinephrine concentrations than did the 13 subjects without this vascular contact (358+/-46 versus 76+/-43 pg/mL, P<0.001). These 5 subjects also exhibited a significant depressor response to clonidine that tended to be greater than that seen in the 13 subjects without vascular contact (-20.6+/-3.2 versus -13.6+/-9 mm Hg). Both race and baseline mean blood pressure had only an independent effect on the depressor response to clonidine. The findings are consistent with the theory that vascular contact with the left ROS may contribute to neurogenically mediated "essential" hypertension in some patients.
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Affiliation(s)
- D Gajjar
- Department of Neurosurgery, Medical University of South Carolina, Charleston, USA
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Ruggiero DA, Underwood MD, Mann JJ, Anwar M, Arango V. The human nucleus of the solitary tract: visceral pathways revealed with an "in vitro" postmortem tracing method. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 2000; 79:181-90. [PMID: 10699650 DOI: 10.1016/s0165-1838(99)00097-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Visceral relay neurons in the nucleus of the solitary tract (NTS) regulate behavior and autonomic reflex functions. NTS projections have been extensively characterized in animal studies but not in humans. For the first time, NTS fiber trajectories in the human medulla oblongata were revealed with an "in vitro" postmortem tracing method. Local intramedullary pathways were labeled by direct pressure injections of free horseradish peroxidase centered on the medial subnucleus at a level adjacent to true obex. Labeled elements were resolved by peroxidase histochemistry as a dark brown intracellular reaction product. A prominent transtegmental system of axons emerged from the NTS injection sites and entered the intermediate reticular zone, a region corresponding to an autonomic reflex center in other mammals. A medial system of axons arched across the dorsomedial reticular formation toward the dorsal medullary raphe and projected ventrally toward the nucleus gigantocellularis. A small lateral fiber trajectory coursed towards the dorsomedial zone of spinal trigeminal nucleus caudalis. Presumptive terminals appeared as dustings of fine punctate processes within the NTS, dorsomotor nucleus and reticular formation. NTS projections in humans resemble those identified in other mammals including primates. Axonal tracing studies predict that visceral impulses in humans may transmit over evolutionarily conserved pathways involved in autonomic feedback control and stress adaptation.
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Affiliation(s)
- D A Ruggiero
- Columbia University College of Physicians and Surgeons, Department of Psychiatry, New York State Psychiatric Institute, New York, NY 10032, USA.
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Schmitz SA, Hohenbleicher H, Koennecke HC, Offermann R, Offermann J, Branding G, Wolf KJ, Distler A, Sharma AM. Neurogenic hypertension. A new MRI protocol for the evaluation of neurovascular compression of the cranial nerves IX and X root-entry zone. Invest Radiol 1999; 34:774-80. [PMID: 10587874 DOI: 10.1097/00004424-199912000-00007] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Neurovascular compression of the rostral ventrolateral medulla (RVLM) has been implicated in the pathogenesis of essential hypertension. Although MRI has been widely used to evaluate the morphologic relation of structures in this region, spatial resolution of the previously used techniques was limited. This article describes the use of a new MRI protocol that combines two sequences with improved spatial resolution and complementary image information as well as a set of defined criteria for image analysis. METHODS MRI of the brain stem was performed in 60 hypertensive and 50 normotensive subjects using a 3D-CISS and a 3D-FISP-MRA sequence. Neurovascular contact in the RVLM was independently assessed by four readers using predefined criteria and compared with a consensus finding. Agreement was expressed by kappa statistics on a 0 to 1 scale. RESULTS Left-sided neurovascular contact within the RVLM was found in 13 (22%) hypertensive and 6 (12%) control subjects. The inter-reader agreement for positive and negative findings ranged from 0.47 to 0.79; agreement to the consensus finding ranged from 0.65 to 0.90. CONCLUSIONS The combination of 3D-CISS and arterial flow-sensitive 3D-FISP, together with the evaluation criteria defined in this study, can be used for describing the finer anatomic features of the brain stem, and in particular for investigation of neurovascular contact of the IX/X cranial nerve root-entry zone. The high quality of images and the substantial or almost perfect reader-consensus agreement should make this protocol useful for future investigations of the neurovascular compression syndrome in patients with essential hypertension and possibly in other neurovascular compression syndromes, such as trigeminal neuralgia and hemifacial spasm.
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Affiliation(s)
- S A Schmitz
- Department of Radiology, Universitätsklinikum Benjamin Franklin, Berlin, Germany
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