Hypertension in patients with cranial nerve vascular compression syndromes and comparison with a population-based cohort

Trigeminal neuralgia

Trigeminal neuralgia (TN) is a facial pain disorder characterized by intense and paroxysmal pain that profoundly affects quality of life and presents complex challenges in diagnosis and treatment. TN can be categorized as classical, secondary and idiopathic. Epidemiological studies show variable incidence rates and an increased prevalence in women and in the elderly, with familial cases suggesting genetic factors. The pathophysiology of TN is multifactorial and involves genetic predisposition, anatomical changes, and neurophysiological factors, leading to hyperexcitable neuronal states, central sensitization and widespread neural plasticity changes. Neurovascular compression of the trigeminal root, which undergoes major morphological changes, and focal demyelination of primary trigeminal afferents are key aetiological factors in TN. Structural and functional brain imaging studies in patients with TN demonstrated abnormalities in brain regions responsible for pain modulation and emotional processing of pain. Treatment of TN involves a multifaceted approach that considers patient-specific factors, including the type of TN, with initial pharmacotherapy followed by surgical options if necessary. First-line pharmacological treatments include carbamazepine and oxcarbazepine. Surgical interventions, including microvascular decompression and percutaneous neuroablative procedures, can be considered at an early stage if pharmacotherapy is not sufficient for pain control or has intolerable adverse effects or contraindications.

Microvascular decompression can effectively reduce arterial blood pressure in patients with Trigeminal Neuralgia

BACKGROUND

Microvascular decompression (MVD) has been used in the treatment of Trigeminal Neuralgia (TN) and arterial hypertension (HTN). Results of several reports have supported its clinical effectiveness, however, little attention has been paid on arterial blood pressure changes caused by MVD in patients with TN.

METHODS

In this single-center retrospective study, a cohort of 80 patients with TN who underwent MVD between 2021 and 2022 had been reviewed. Clinical data such as age, gender, pain duration, operation time, side and range of pain, HTN history, treatment history, VAS score, mean arterial pressure (MAP), and nausea or vomiting after operation were collected and analyzed via Linear regression to select possible related factors. Then, multiple linear regression of the possible predictors was used to identify the variables that significantly predicted MAP reduction.

RESULTS

The VAS scores of TN patients after MVD surgery was significantly lower than that before operation, irrespective of the gender, side and range of pain, HTN history, RF history, and PONV (Wilcoxon test, P < 0.001). MVD can significantly decreased the blood pressure of TN patients, without interference from other factors. (MAP reduction ratio=14.46% ± 12.32%) (paired t-test, P < 0.001). The univariate and Multiple linear regression analysis showed that the preoperative MAP was significantly related to MAP reduction ratio (P < 0.001).

CONCLUSIONS

In patients with TN, MVD can significantly decrease arterial blood pressure. Blood pressure reductions were more prominent when cases with higher preoperative MAP.

Familial occurrence of classical and idiopathic trigeminal neuralgia

Trigeminal neuralgia (TN) is a severe facial pain disease with unknown pathogenesis. It has been thought that the familial form of TN is rare with a prevalence of about 1-2% among affected individuals, but emerging evidence suggests a role of genetic factors. This study examined the occurrence of familial TN among patients with classical or idiopathic TN. Patients with TN recruited from a hospital registry received an informed consent form with a questionnaire, and individuals reporting other family members with TN underwent a structured phone-interview. For affected family members, type of TN, available clinical, imaging, management results and available hospital patient records were studied. Pedigrees for all affected families were established. This study included 268 patients with either classical or idiopathic TN. The familial form of TN was present in 41/268 (15.3%) patients, that is, 37/244 (15.2%) patients with classical TN and in 4/24 (16.7%) with idiopathic TN. Total 38 families were identified, with two affected members in 32/38 families (84.2%), three affected family members in 5/38 (13.2%) and four family members in 1/38 (2.6%) families. Comparing the 41 familial TN cases with the 227 sporadic TN patients showed significantly earlier onset of TN and a significantly higher occurrence of right-sided pain in familial cases, while there was no difference in gender distribution, occurrence of arterial hypertension or trigeminal branch involved. Among patients with classical or idiopathic TN, the occurrence of the familial form of the disease is more frequent than traditionally assumed.

Percutaneous Radiofrequency Thermocoagulation in Trigeminal Neuralgia : Analysis of Early and Late Outcomes of 156 Cases and 209 Interventions

Objective

Trigeminal neuralgia is one of the most common causes of facial pain. Our aim is to investigate the efficacy and borders of percutaneous radiofrequency thermocoagulation in the treatment of trigeminal neuralgia.

Methods

Between May 2007 and April 2017, 156 patients with trigeminal neuralgia were treated with radiofrequency thermocoagulation. These 156 patients underwent 209 procedures. In our study, we investigated the early and late results of percutaneous radiofrequency thermocoagulation under guiding fluoroscopic imaging in the treatment of trigeminal neuralgia. Barrow Neurological Institute (BNI) pain scale was used for grading the early results. In addition, Kaplan-Meier survival analysis was used to assess long-term outcomes. Of the 156 patients who underwent radiofrequency thermocoagulation for trigeminal neuralgia, 45 had additional disease. Patients with this condition were evaluated with their comorbidities. Early and late results were compared with those without comorbidity.

Results

In 193 of 209 interventions BNI pain scale I to III results were obtained. Out of the 193 successful operation 136 patients (65.07%) were discharged as BNI I, 14 (6.70%) as BNI II, 43 (20.58%) as BNI III. Sixteen patients (7.65%) remained uncontrolled (BNI IV and V). While the treatment results of trigeminal neuralgia patients with comorbidity seem more successful in the early period, this difference was not observed in follow-up examinations.

Conclusion

Finally, we concluded that percutaneous radiofrequency thermocoagulation of the Gasserian ganglion is a safe and effective method in the treatment of trigeminal neuralgia. However, over time, the effectiveness of the treatment decreases. Neverthless, the reapprability of this intervention gives it a distinct advantage.

Efficacy of microvascular decompression on the vascular compression type of neurogenic hypertension: A meta-analysis

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.

Trigeminal Neuralgia: Basic and Clinical Aspects

The trigeminal nerve is the largest of all cranial nerves. It has three branches that provide the main sensory innervation of the anterior two-thirds of the head and face. Trigeminal neuralgia (TN) is characterized by sudden, severe, brief, and stabbing recurrent episodes of facial pain in one or more branches of the trigeminal nerve. Pain attacks can occur spontaneously or can be triggered by non-noxious stimuli, such as talking, eating, washing the face, brushing teeth, shaving, a light touch or even a cool breeze. In addition to pain attacks, a proportion of the patients also experience persistent background pain, which along with autonomic signs and prolonged disease duration, represent predictors of worse treatment outcomes. It is now widely accepted that the presence of a neurovascular compression at the trigeminal root entry zone is an anatomic abnormality with a high correlation with classical TN. However, TN may be related to other etiologies, thus presenting different and/or additional features. Since the 1960s, the anticonvulsant carbamazepine is the drug of choice for TN treatment. Although anti-epileptic drugs are commonly used to treat neuropathic pain in general, the efficacy of carbamazepine has been largely limited to TN. Carbamazepine, however, is associated with dose-limiting side-effects, particularly with prolonged usage. Thus, a better understanding and new treatment options are urgently warranted for this rare, but excruciating disease.

Microvascular decompression in patients with hemifacial spasm

PURPOSE

To study blood pressure alterations after microvascular decompression (MVD) surgery in patients with hemifacial spasm (HFS).

METHODS

A retrospective study was performed to review HFS patients who received MVD surgery between January 2014 and December 2016. Vessels that were considered to be responsible for HFS were determined by reviewing the brain magnetic resonance imaging, magnetic resonance angiography, and surgical video. Blood pressure measurements were performed 1 day before (preoperative) and 7 days after (postoperative) the MVD surgery. Pre- and postoperative blood pressure measurements were compared.

RESULTS

A total of 374 patients were included in the study, with 118 (31.6%) male patients, age 53.8 ± 9.9 years old, and 141 (37.7%) patients with hypertension. Systolic blood pressure had statistically significant decrease in patients with (134.5 ± 8.2-132.6 ± 9.1 mmHg, p = .01) or without (125.6 ± 9.1-123.8 ± 10.0 mmHg, p = .01) hypertension. Diastolic blood pressure only had statistically significant decrease in patients with hypertension (83.0 ± 5.8-82.0 ± 6.5 mmHg, p = .04). Analyses in all the study patients and in the subgroup of patients with hypertension showed that more statistically significant blood pressure reductions were observed when left-side vessel or vertebrobasilar artery was involved.

CONCLUSION

In patients with HFS, MVD not only decreased blood pressure in patients with hypertension but also affected blood pressure in patients without hypertension. Blood pressure reductions were more prominent when left-side vessel or vertebrobasilar artery was involved.

Vascular tortuosity in relationship with hypertension and posterior fossa volume in hemifacial spasm

Background

Hemifacial spasm (HFS) is a disabling neurological condition. Vascular tortuosity in HFS patients has not been quantified objectively and its relationship with hypertension and posterior fossa volume (PF) is unknown. In a case control magnetic resonance imaging and angiographic (MRI/A) study, we quantified and compared the vascular tortuosity in HFS and controls, and evaluated its relationship with hypertension and PF.

Methods

Using a commercially available vessel probe tool, an index of tortuosity based on vessel over chord length was employed to quantify vascular tortuosity of the vertebral (VA) and basilar arteries (BA) in 79 subjects (40 HFS, 39 controls).

Results

The tortuosity index of the BA (1.09 vs 1.16, p = 0.26, 95 % CI 1.07, 1.23), RVA (1.15 vs 1.15, p = 0.83, 95 % CI 1.06, 1.38) and LVA (1.14 vs 1.288, p = 0.16, 95 % CI 1.14, 1.44) was not different between HFS and controls, with adjustments for PF volume and hypertension.

Conclusions

Contrary to popular belief, our study showed that taking into account hypertension and PF volume, vascular tortuosity of the vertebrobasilar arteries is unlikely to be a major etiologic factor in HFS, though its role in select individuals cannot be excluded. The complex interplay of facial nerve hyperexcitability, genetic predisposition, vascular tortuosity, posterior fossa volume and hypertension needs to be further evaluated.

Revisiting the link between hypertension and hemifacial spasm

The relationship between hypertension and hemifacial spasm (HFS) has been debated. Microvascular decompression surgery is effective in some HFS patients with uncontrolled hypertension. To address current gaps in knowledge, we conducted a meta-analysis of case-control studies that have examined the prevalence of hypertension in HFS patients compared to non-HFS controls. We also evaluated the implications and limitations of the pooled studies. We identified 62 studies from PubMed, The Cochrane Library, Web of Science and Scholar.google.com and six studies that fit our inclusion criteria were included. A random-effects model was used to derive the pooled estimate of the Odds Ratio. The data was plotted on a Forest plot. A pooled analysis involving 51585 subjects, 549 cases, 720 neurological controls and 50316 controls from the general population, showed that HFS patients had a higher chance of developing hypertension (OR = 1.72, 95% CI = (1.12, 2.31), p-value  <0.001). The prevalence of hypertension was higher in HFS patients as compared to non-HFS patients. This meta-analysis highlights a positive correlation between hypertension and HFS. Blood pressure should be closely monitored during the follow-up of HFS patients. Preliminary links between ventrolateral medullary (VLM) compression and HFS should be further evaluated in future studies.