Compression of the internal jugular vein by the transverse process of the atlas as the cause of cerebellar hemorrhage after supratentorial craniotomy

C1 Transverse Process Resection for Management of Jugular Stenosis

BACKGROUND AND IMPORTANCE

Idiopathic intracranial hypertension, also known as pseudotumor cerebri, often presents with severe headache and associated vision loss. Venous outflow obstruction has been noted as a prominent etiologic factor in many cases, and previous anatomic studies have shown that the internal jugular (IJ) vein at the skull base can be prone to compression by the neighboring bony structures.

CLINICAL PRESENTATION

We present a case of 13-yr-old male with a multifactorial intracranial hypertension including compression of the IJ vein by the transverse process of C1. Computerized tomography angiographic imaging revealed bilateral stenosis of the IJ veins due to compression from the transverse processes of C1. Medical management and shunt were attempted without resolution of symptoms. A hemodynamically significant stenosis at the right IJ was confirmed with manometry and so the C1 transverse process was resected and a stent placed endovascularly with resolution of pressure gradient and clinical symptoms.

CONCLUSION

Contribution of C1 compression to this patient's intracranial hypertension suggests that evaluation for IJ compression below the skull base may be needed to identify the underlying cause of intracranial hypertension in certain patients. Furthermore, surgical decompression of the IJ vein may be required as part of the treatment strategy. If venous stenting is being considered, this decompressive step must be taken before stenting is performed. We offer this case as evidence that decompression of the IJ vein by C1 lateral mass resection can be an effective and novel technique in the repertoire of neurosurgical management of intracranial hypertension.

Risk factors of postoperative remote intracerebral hemorrhage after craniotomy for ruptured cerebral aneurysms

Objective

We aimed to identify the relation between perioperative cerebrospinal fluid (CSF) drain through lumbar drainage (LD) and development of postoperative (POP) remote intracerebral hemorrhage (rICH) in craniotomy to treat ruptured intracranial aneurysms.

Methods

We retrospectively reviewed consecutive patients who underwent craniotomy for ruptured cerebral aneurysms at the authors’ institution between 1998 and 2004. We subsequently compared the incidence and characteristics of POP rICH between the patients who had a perioperative LD and those who did not. All statistical analyses were conducted using the software package SPSS 19.0 (SPSS Inc., Chicago, IL, USA). A p value of <0.05 was considered statistically significant.

Results

We enrolled 688 patients, of which 80 patients (11.6%) received perioperative LD, and 608 did not. LD and non-LD groups were comparable because although clinical characteristics of the two groups were significantly different considering history of hypertension, timing of surgery, and closed system negative pressure suction drain (SD) placement, none of these three variables was an independent risk factor associated with POP rICH in multivariate analysis. POP rICH incidence was significantly higher in the LD goup (12.5%) than non-LD group (0.8%) (p=0.000) in univariate analysis. LD placement was the only independent risk factor associated with the development of rICH in multivariate logistic regression analysis.

Conclusions

POP rICH incidence was significantly higher in patients who were managed with perioperative LD than in those who did not. LD insertion in craniotomy for ruptured intracranial aneurysm, should be closely monitored to address the occurrence of POP rICH.

Remote Cerebellar Haemorrhage: A Potential Iatrogenic Complication of Spinal Surgery

We report the case of a 51-year-old man with no significant past medical history, who underwent elective revision spinal surgery and subsequently developed intracranial hypotension, remote cerebellar haemorrhage (RCH), and mild hydrocephalus on the fourth postoperative day. Remote cerebellar haemorrhage is a known complication of supratentorial surgery. This iatrogenic phenomenon may also occur following spinal surgery, due to dural tearing and rapid cerebral spinal fluid (CSF) leakage, resulting in intracranial hypotension and cerebellar haemorrhage. This complication may result in severe permanent neurologic sequelae; hence, it is of pertinence to diagnose and manage it rapidly in order to optimise patient outcome.

Cerebral venous overdrainage: an under-recognized complication of cerebrospinal fluid diversion

Understanding the altered physiology following cerebrospinal fluid (CSF) diversion in the setting of adult hydrocephalus is important for optimizing patient care and avoiding complications. There is mounting evidence that the cerebral venous system plays a major role in intracranial pressure (ICP) dynamics especially when one takes into account the effects of postural changes, atmospheric pressure, and gravity on the craniospinal axis as a whole. An evolved mechanism acting at the cortical bridging veins, known as the “Starling resistor,” prevents overdrainage of cranial venous blood with upright positioning. This protective mechanism can become nonfunctional after CSF diversion, which can result in posture-related cerebral venous overdrainage through the cranial venous outflow tracts, leading to pathological states. This review article summarizes the relevant anatomical and physiological bases of the relationship between the craniospinal venous and CSF compartments and surveys complications that may be explained by the cerebral venous overdrainage phenomenon. It is hoped that this article adds a new dimension to our therapeutic methods, stimulates further research into this field, and ultimately improves our care of these patients.

Remote Cerebellar Haemorrhage after Burr Hole Drainage of Chronic Subdural Haematoma: A Case Report

Remote cerebellar haemorrhage (RCH) is an unusual complication of supratentorial neurosurgical procedures. Even the rarer is cerebellar haemorrhage occurring after supratentorial burr hole drainage of Chronic Subdural Haematoma (CSDH). The exact mechanism is still unclear despite some possible causative factors such as rapid evacuation of haematoma and overdrainage of CSF (Cerebrospinal Fluid). We report a 80-year-old male patient who developed cerebellar haemorrhage after burr hole drainage of left frontoparietal chronic subdural haematoma and discuss the possible aetiological mechanisms through the review of the current literature.

The cerebral venous system and the postural regulation of intracranial pressure: implications in the management of patients with cerebrospinal fluid diversion

Loss of cerebrospinal fluid (CSF) occurs commonly in daily neurosurgical practice. Understanding the altered physiology following CSF loss is important for optimization of patient care and avoidance of complications. There is overwhelming evidence now that the cerebral venous system plays a major role in intracranial pressure (ICP) dynamics especially when one takes into account the effects of postural changes, atmospheric pressure, and gravity on the craniospinal axis as a whole. The CSF and cerebral venous compartments are tightly coupled in two important ways. CSF is resorbed into the venous system, and there is also an evolved mechanism that prevents overdrainage of venous blood with upright positioning known as the Starling resistor. With loss of CSF pressure, this protective mechanism could become nonfunctional which may result in posture-related venous overdrainage through the cranial venous outflow tracts leading to pathologic states. This review article summarizes the relevant anatomic and physiologic basis of the relationship between the craniospinal venous and CSF compartments in the setting of CSF diversion. It is hoped that this article improves our understanding of ICP dynamics after CSF loss, adds a new dimension to our therapeutic methods, stimulates further research into this field, and ultimately improves our care of these patients.

Remote cerebellar hemorrhage after supratentorial procedures (part 1): a systematic review

A remote cerebellar hemorrhage (RCH) is a spontaneous bleeding in the posterior fossa, which may rarely occurs as a complication of supratentorial procedures, and it shows a typical bleeding pattern defined "the zebra sign." However, its pathophysiology still remains unknown. We performed a comprehensive review collecting all cases of RCH after supratentorial craniotomies reported in literature in order to identify the most frequently associated procedures and the possible risk factors. We assessed percentages of incidence and 95 % confidence intervals of all demographic, neuroradiological, and clinical features of the patients. Univariate and multivariate analyses were used to evaluate their association with outcome. We included 49 articles reporting 209 patients with a mean age of 49.09 ± 17.07 years and a male/female ratio 130/77. A RCH was more frequently reported as a complication of supratentorial craniotomies for intracranial aneurysms, tumors debulking, and lobectomies. In the majority of cases, RCH occurrence was associated with impairment of consciousness, although some patients remained asymptomatic or showed only slight cerebellar signs. Coagulation disorders, perioperative cerebrospinal fluid drainage, hypertension, and seizures were the most frequently reported risk factors. Zebra sign was the most common bleeding pattern, being observed in about 65 % out of the cases, followed by parenchymal hematoma and mixed hemorrhage in similar percentages. A multivariate analysis showed that symptomatic onset and intake of antiplatelets/anticoagulants within a week from surgery were independent predictors of poor outcome. However, about 75 % out of patients showed a good outcome and a RCH often appeared as a benign and self-limiting condition, which usually did not require surgical treatment, but only prolonged clinical surveillance, unless in the event of the occurrence of complications.

Remote cerebellar haemorrhage from site of craniotomy: A report of two cases

Remote cerebellar haemorrhage (RCH) is a rare complication of neurosurgical procedures seldom requiring intervention. We report two cases of RCH. The first unilateral RCH is asymptomatic, the other is bilateral and associated with supratentorial haemorrhage and hydrocephalus requiring intervention. We propose multiple foci of haemorrhage as an adverse prognostic marker in RCH.

Remote Cerebellar Hemorrhage after Supratentorial Burr-Hole Trepanation for Unilateral Chronic Subdural Hematoma: Case Report

Remote cerebellar hemorrhage (RCH) after burr-hole evacuation for chronic subdural hematoma (cSDH) is a rare and uncommon complication of minor supratentorial surgery with very few reports in the literature and an uncertain etiology. We present the case of a 62-year-old male who underwent single burr-hole trepanation for unilateral cSDH, revealing incidental RCH on routine postoperative computed tomography (CT) scan most likely resulting from overdrainage of cerebrospinal fluid (CSF) within the postoperative period. The patient recovered well without further neurosurgical intervention. Intra- and postoperative drainage of large volumes of CSF and the venous origin of the bleeding are accepted factors in the controversial concept of its pathophysiology. Alterations in transtentorial pressure and stretching of superficial cerebellar veins with consequent rupture seem to constitute a useful concept, although details on mechanical or hemodynamic changes still remain unknown. A multifactorial etiology with CSF-overdrainage as the major main factor seems reasonable. Neurosurgeons should be aware of the possibility of RCH even in minor supratentorial procedures such as simple burr-hole trepanation. There is a tendency towards more benign courses, but higher patient age and severity of RCH correlate with a poor outcome. Early diagnosis of RCH and close monitoring reduce unnecessary diagnostic and therapeutic interventions in these patients, probably affecting morbidity and mortality.

Patterns of chronic venous insufficiency in the dural sinuses and extracranial draining veins and their relationship with white matter hyperintensities for patients with Parkinson's disease

BACKGROUND

Idiopathic Parkinson's disease (IPD) remains one of those neurodegenerative diseases for which the cause remains unknown. Many clinically diagnosed cases of IPD are associated with cerebrovascular disease and white matter hyperintensities (WMHs). The purpose of this study was to investigate the presence of transverse sinus and extracranial venous abnormalities in IPD patients and their relationship with brain WMHs.

METHODS

Twenty-three IPD patients and 23 age-matched normal controls were recruited in this study. They had conventional neurologic magnetic resonance structural and angiographic scans and, for blood flow, quantification of the extracranial vessels. Venous structures were evaluated with two-dimensional time of flight; flow was evaluated with two-dimensional phase contrast; and WMH volume was quantified with T2-weighted fluid-attenuated inversion recovery. The IPD and normal subjects were classified by both the magnetic resonance time-of-flight and phase contrast images into four categories: (1) complete or local missing transverse sinus and internal jugular veins on the time-of-flight images; (2) low flow in the transverse sinus and stenotic internal jugular veins; (3) reduced flow in the internal jugular veins; and (4) normal flow and no stenosis.

RESULTS

Broken into the four categories with categories 1 to 3 combined, a significant difference in the distribution of the IPD patients and normal controls (χ(2) = 7.7; P < .01) was observed. Venous abnormalities (categories 1, 2, and 3) were seen in 57% of IPD subjects and in only 30% of controls. In IPD subjects, category type correlated with both flow abnormalities and WMHs.

CONCLUSIONS

From this preliminary study, we conclude that a major fraction of IPD patients appear to have abnormal venous anatomy and flow on the left side of the brain and neck and that the flow abnormalities appear to correlate with WMH volume. Studies with a larger sample size are still needed to confirm these findings.

Potential involvement of the extracranial venous system in central nervous system disorders and aging

BACKGROUND

The role of the extracranial venous system in the pathology of central nervous system (CNS) disorders and aging is largely unknown. It is acknowledged that the development of the venous system is subject to many variations and that these variations do not necessarily represent pathological findings. The idea has been changing with regards to the extracranial venous system.

DISCUSSION

A range of extracranial venous abnormalities have recently been reported, which could be classified as structural/morphological, hemodynamic/functional and those determined only by the composite criteria and use of multimodal imaging. The presence of these abnormalities usually disrupts normal blood flow and is associated with the development of prominent collateral circulation. The etiology of these abnormalities may be related to embryologic developmental arrest, aging or other comorbidities. Several CNS disorders have been linked to the presence and severity of jugular venous reflux. Another composite criteria-based vascular condition named chronic cerebrospinal venous insufficiency (CCSVI) was recently introduced. CCSVI is characterized by abnormalities of the main extracranial cerebrospinal venous outflow routes that may interfere with normal venous outflow.

SUMMARY

Additional research is needed to better define the role of the extracranial venous system in relation to CNS disorders and aging. The use of endovascular treatment for the correction of these extracranial venous abnormalities should be discouraged, until potential benefit is demonstrated in properly-designed, blinded, randomized and controlled clinical trials.

Internal jugular venous abnormalities in transient monocular blindness

Background

The etiology of transient monocular blindness (TMB) in patients without carotid stenosis has been linked to ocular venous hypertension, for their increased retrobulbar vascular resistance, sustained retinal venule dilatation and higher frequency of jugular venous reflux (JVR). This study aimed to elucidate whether there are anatomical abnormalities at internal jugular vein (IJV) in TMB patients that would contribute to impaired cerebral venous drainage and consequent ocular venous hypertension.

Methods

Contrast-enhanced axial T1-weighted magnetic resonance imaging (MRI) was performed in 23 TMB patients who had no carotid stenosis and 23 age- and sex-matched controls. The veins were assessed at the upper IJV (at C1–3 level) and the middle IJV (at C3–5 level). Grading of IJV compression/stenosis was determined bilaterally as follows: 0 = normal round or ovoid appearance; 1 = mild flattening; 2 = moderate flattening; and 3 = severe flattening or not visualized.

Results

There was significantly more moderate or severe IJV compression/stenosis in the TMB patients at the left upper IJV level and the bilateral middle IJV level. Defining venous compression/stenosis scores ≥ 2 as a significant cerebral venous outflow impairment, TMB patients were found to have higher frequency of significant venous outflow impairment at the upper IJV level (56.5% vs. 8.7%, p = 0.0005) and the middle IJV level (69.6% vs. 21.7%, p=0.0011).

Conclusions

TMB Patients with the absence of carotid stenosis had higher frequency and greater severity of IJV compression/stenosis which could impair cerebral venous outflow. Our results provide evidence supporting that the cerebral venous outflow abnormality is one of the etiologies of TMB.

A comparative study of magnetic resonance venography techniques for the evaluation of the internal jugular veins in multiple sclerosis patients

BACKGROUND AND PURPOSE

The use of magnetic resonance imaging (MRI) to assess the vascular nature of diseases such as multiple sclerosis (MS) is a growing field of research. This work reports on the application of MR angiographic (MRA) and venographic (MRV) techniques in assessing the extracranial vasculature in MS patients.

MATERIALS AND METHODS

A standardized MRI protocol containing 2D TOF-MRV and dynamic 3D contrast-enhanced (CE) MRAV was run for 170 MS patients and 40 healthy controls (HC). The cross-sectional area (CSA) of the internal jugular veins (IJVs) was measured at three neck levels in all subjects for both MRV techniques to determine the presence of venous stenoses. All data were analyzed retrospectively.

RESULTS

For the values where both methods showed signal, the 3D method showed larger CSA measurement values compared to 2D methods in both IJVs, in both MS and HC subjects which was confirmed with student paired t-tests. Of the 170 MS patients, 93 (55%) in CE-MRAV and 103 (61%) in TOF-MRV showed stenosis in at least one IJV. The corresponding numbers for the 40 HC subjects were 2 (5%) and 4 (10%), respectively. Carotid ectasias with IJV stenosis were seen in 26 cases (15%) with 3D CE-MRAV and were not observable with 2D TOF-MRV. Carotid ectasias were not seen in the HC group. In the 2D TOF-MRV data, banding of the IJVs related to slow flow was seen in 58 (34%) MS cases and in no HC cases. MS patients showed lower average CSAs than the HC subjects.

CONCLUSION

The 3D CE MRAV depicted the vascular anatomy more completely than the 2D TOF-MRV. However, the 3D CE MRAV does not provide any information about the flow characteristics which are indirectly available in the 2D TOF-MRV in those cases where there is slow flow.

Prevalence of incidental narrowing of the superior segment of the internal jugular vein in patients without multiple sclerosis

PURPOSE

Internal jugular vein (IJV) narrowing superiorly is likely relatively frequent. IJV narrowing has been proposed as a potential pathophysiologic component for multiple sclerosis (MS). Our purpose was to investigate the prevalence of incidental superior IJV narrowing in patients imaged with neck computed tomography angiography (CTA) for reasons unrelated to IJV pathology or MS.

METHODS

We retrospectively identified 164 consecutive adult patients who had undergone neck CTA in which at least one IJV superior segment was opacified (158 right, 155 left IJVs). At the narrowest point of the upper IJV, each IJV was assessed for dominance, graded (shape and narrowing), measured (diameter and area), and located (axially and craniocaudally). Associations were analyzed using Spearman rank correlations (p < 0.05 significant). Medical records were reviewed for MS.

RESULTS

Among 164 patients, at least one IJV was: absent/pinpoint in 15 % (25/164), occluded/nearly occluded in 26 % (43/164). Shape, narrowing, and the three measurements all correlated with each other (all p < 0.01). Lateral location with respect to C1 transverse foramen correlated with subjectively and objectively smaller IJVs (p < 0.01). The most common craniocaudal location was at the C1 transverse process (79 % (125/158) of right and 81 % (126/155) of left IJVs). No patient had a diagnosis of MS.

CONCLUSIONS

The appearance of the superior IJV is variable, with an occlusive/near-occlusive appearance present in approximately one-quarter of patients without known MS undergoing CTA. Radiologists should be aware of and cautious to report or ascribe clinical significance to this frequent anatomic variant.

Catheter venography and endovascular treatment of chronic cerebrospinal venous insufficiency

Multiple sclerosis (MS) is a disorder characterized by damage to the myelin sheath insulation of nerve cells of the brain and spinal cord affecting nerve impulses which can lead to numerous physical and cognitive disabilities. The disease, which affects over 500,000 people in the United States alone, is widely believed to be an autoimmune condition potentially triggered by an antecedant event such as a viral infection, environmental factors, a genetic defect or a combination of each. Chronic cerebrospinal venous insufficiency (CCSVI) is a condition characterized by abnormal venous drainage from the central nervous system that has been theorized to have a possible role in the pathogenesis and symptomatology of MS (1). A significant amount of attention has been given to this theory as a possible explanation for the etiology of symptoms related to MS patients suffering from this disease. The work of Dr. Zamboni, et al, who reported that treating the venous stenoses causing CCSVI with angioplasty resulting in significant improvement in the symptoms and quality of life of patients with MS (2) has led to further interest in this theory and potential treatment. The article presented describes endovascular techniques employed to diagnose and treat patients with MS and CCSVI.

Chronic cerebrospinal venous insufficiency and multiple sclerosis: history and background

Multiple sclerosis (MS) is a chronic inflammatory disorder of the central nervous system (CNS) most commonly characterized by focal areas of myelin destruction, inflammation and axonal transection. The multicentric inflammation and demyelination of the brain and spinal cord are associated with variable neurologic symptoms ranging from mild dysfunction to debilitating. Typically, these symptoms are marked by episodes of clinical worsening followed by improvement. The cause of this disease remains unclear currently, but the underlying etiology is generally considered to be immunologically based. Other factors, including genetic, environmental and infectious influences have been implicated, as well. Now recent studies have proposed that extracranial venous obstruction, termed chronic cerebrospinal venous insufficiency (CCSVI) may have a role in the pathogenesis of MS or many of its associated clinical manifestations. It is postulated that venous narrowing affecting one or more of the jugular veins and/or the azygous vein in the chest may be responsible for abnormal blood flow in the veins draining the brain and spinal cord. The abnormal flow may initiate and/or sustain a local inflammatory response at the blood-brain barrier that promote pathological changes within the CNS. This review presents the history of the relationship between the vascular system and MS and explores the background of basic and clinical investigations that led to the concept of CCSVI.

Remote cerebellar hemorrhage due to ventriculoperitoneal shunt in an infant: a case report

INTRODUCTION

Cerebellar hemorrhage remote from the operative site is an unpredictable and rare complication in neurosurgery, with reported rates of morbidity and mortality in the literature of 8.4% and 7.8%, respectively. The range of procedures associated with remote cerebellar hemorrhage is diverse and includes both supratentorial and spinal procedures that entail significant cerebral spinal fluid loss or resection of supratentorial content. We present here the first documented case of remote cerebellar hemorrhage after controlled supratentorial cerebral spinal fluid drainage by ventriculoperitoneal shunt, and discuss the proposed pathophysiology and treatment.

CASE PRESENTATION

We present the case of a four-month-old Saudi Arabian male baby who presented with progressive symptoms and signs of congenital hydrocephalus. An uneventful ventriculoperitoneal shunting was performed with our patient recovering smoothly in the immediate postoperative period. On the next day, he had frequent episodes of vomiting and became lethargic. An urgent computed tomography scan of his brain revealed mild ventricular decompression and unexpected cerebellar hemorrhage. The infant was put under close observation, with marked spontaneous improvement over 48 hours and complete resolution of the hemorrhage on a follow-up computed tomography brain scan two weeks later. On regular outpatient visits at one, three and twelve months, he had no neurological deficit.

CONCLUSION

Remote cerebellar hemorrhage is a complication that remains enigmatic in terms of both the underlying mechanism and clinical behavior. Our case revealed that the risk factors identified in the literature are not sufficient in predicting patients at risk of developing remote cerebellar hemorrhage. Our report also adds to the growing body of evidence challenging the currently accepted hypothesis explaining the pathomechanism of remote cerebellar hemorrhage. It thereby remains an unpredictable hazard that requires further study and increased awareness, as many cases in the literature are incidental findings.

Patients with multiple sclerosis with structural venous abnormalities on MR imaging exhibit an abnormal flow distribution of the internal jugular veins

PURPOSE

To evaluate extracranial venous structural and flow characteristics in patients with multiple sclerosis (MS).

MATERIALS AND METHODS

Two hundred subjects with MS from two sites (n = 100 each) were evaluated with magnetic resonance (MR) imaging at 3 T. Contrast-enhanced time-resolved MR angiography and time-of-flight MR venography were used to assess vascular anatomy. Two-dimensional phase-contrast MR imaging was used to quantify blood flow. The MS population was divided into two groups: those with evident internal jugular vein (IJV) stenoses (stenotic group) and those without (nonstenotic group).

RESULTS

Of the 200 patients, 136 (68%) showed IJV structural abnormalities, including unilateral or bilateral stenoses at different levels in the neck (n = 101; 50.5%) and atresia (n = 35; 17.5%). The total IJV flow normalized to the total arterial flow of the stenotic group (56% ± 22) was significantly lower than that of the nonstenotic group (77% ± 14; P < .001). The arterial/venous flow mismatch in the stenotic group (12% ± 15) was significantly greater than that in the nonstenotic group (6% ± 12; P < .001). The ratio of subdominant venous flow rate (Fsd) to dominant venous flow rate (Fd) for the stenotic group (0.38 ± 0.27) was significantly lower than for the nonstenotic group (0.59 ± 0.23; P < .001). The majority of the stenotic group (67%) also had an Fsd of less than 3 mL/s, a Fd/Fsd ratio greater than 3:1, and/or a total IJV flow rate of less than 8 mL/s.

CONCLUSIONS

MR imaging provides a noninvasive means to separate stenotic from nonstenotic MS cases. The former group was more prevalent in the present MS population and carried significantly less flow in the IJVs than the latter.

Remote cerebellar hemorrhage after lumbar spinal surgery

Remote cerebellar hemorrhage (RCH) is rare but potentially lethal as a complication of spinal surgery. We recently experienced a case of RCH in a 61-year-old man who showed mental deterioration after lumbar spinal surgery. There was dural tearing with subsequent cerebrospinal fluid (CSF) loss during the surgery. Brain computed tomography scan revealed cerebellar hemorrhage, 3rd and 4th ventricular hemorrhage and pneumocephalus. He underwent suboccipital craniectomy and hematoma removal. The most important pathomechanism leading to RCH after spinal surgery has been known to be venous bleeding due to caudal sagging of cerebellum by rapid leak of large amount of CSF which seems to be related with this case. Dural repair and minimizing CSF loss after intraoperative dural tearing would be helpful to prevent postoperative RCH.

Remote cerebellar hemorrhage complicated after supratentorial surgery: retrospective study with review of articles

OBJECTIVE

Remote cerebellar hemorrhage (RCH) is one of the rare complications occurring after supratentorial surgery, and its pathomechanism is poorly understood. We report 10 cases of RCH from our institution and review 154 cases from a database in order to delineate incidence, common presentation, risk factors, and outcomes of this complication. In addition, the means of prevention are discussed.

METHODS

We reviewed the medical records of 10 patients who experienced RCH after undergoing supratentorial surgery at our institution between 2001 and 2008. A database search in Medline revealed 154 cases of RCH in the English literature. Characteristic features were analyzed and compared.

RESULTS

There were 10 cases of RCH among 3307 supratentorial surgery cases, indicating a 0.3% incidence. All patients had characteristic imaging features of RCH, namely a streaky bleeding pattern in the superior folia of the cerebellum. Seven patients had a history of preoperative hypertension. Four cases were related to cerebral aneurysms, and other four developed after the removal of brain tumors. Cerebrospinal fluid (CSF) drainage apparatuses were installed postoperatively in all cases. Outcomes according to modified Rankin scale (mRS) were good in 7 patients, with 1 fatal case.

CONCLUSION

RCH is a rare complication after supratentorial surgery, and the exact etiology still remains uncertain. Hypertension and perioperative loss of CSF seem positively correlated with RCH, but no single risk factor is totally responsible. Patients with RCH should be closely observed to improve their prognosis.

Remote cerebellar hemorrhage and iliofemoral vein thrombosis after supratentorial craniotomy

INTRODUCTION

Cerebellar hemorrhage following supratentorial craniotomy is rare. Its clinical symptoms are often mild and transient.

DISCUSSION

Here, we report a case of cerebellar hemorrhage associated with iliofemoral vein thrombosis as a complication of anterior temporal lobectomy and amygdalohippocampectomy for refractory medial temporal epilepsy.

Remote cerebellar hemorrhage after supratentorial unruptured aneurysmal surgery: report of three cases

We report three cases of remote cerebellar hemorrhage that developed after supratentorial unruptured aneurysmal surgery. In all cases, digital subtraction angiography was performed before each operation in order to rule out other vascular abnormalities, especially around the operative field or the posterior circulation. In addition, all patients were screened for any previous history of bleeding tendencies or other related medical disorders. Each patient underwent clipping surgery via the pterional approach. Remote cerebellar hemorrhage was identified on post-operative computed tomographic scans. In all cases, there was no evidence of significant associated long-term morbidity. A consideration of the possible pathophysiologic mechanisms underlying these post-operative remote cerebellar hemorrhages and suggested strategies for avoiding such complications are discussed.

Lesionectomy in epileptogenic gangliogliomas: seizure outcome and surgical results

We retrospectively analysed seizure outcome and surgical results in a series of 21 patients with ganglioglioma treated with lesionectomy. The 21 patients (13 males, eight females) had a history of epilepsy longer than 1 year and post-operative follow up of at least 1 year. Information on the duration of the seizures, type and frequency was retrieved from medical records. In all patients, surgery was limited to the tumour. The interval between onset of seizures and surgery ranged from 1 to 35 years (mean 11). Patient age ranged from 6 to 61 years (mean 27.5). Fifteen patients (71.4%) had complex partial seizures and six had simple partial seizures. Secondary generalisation was present in 10 patients (47.6%). Seizure frequency varied from several per day to one per month. Sixteen tumours were temporal (76.1%; 11 temporo-mesial, five temporo-lateral), and five were extratemporal (23.8%). The mean follow-up period was 5.4 years (range: 1.25-10 years). No tumour progression was observed. No patient died during surgery or the post-operative course. Fourteen patients (66.6%) were Engel class I (five temporo-mesial, five temporo-lateral, four extratemporal) and seven (33.3%) were Engel class II. Post-operative complications were observed in six patients (28.6%), two of whom had cerebellar haemorrhage, possibly due to increased transmural venous pressure. In our patients with temporal neocortical and extratemporal ganglioglioma, lesionectomy allowed good seizure control. The unsatisfactory outcome for mesiotemporal gangliogliomas might indicate the need for extensive neurophysiological presurgical evaluation in order to perform tailored surgery. To avoid cerebellar haemorrhage, attention should be paid to those factors involved in transmural venous pressure increases.

Remote cerebellar hemorrhage: A review

Remote cerebellar hemorrhage remains a complication rarely occurring after supratentorial surgery (<5%) and presumably even less frequent after spinal surgery. Although the pathomechanisms leading to RCH with its typical bleeding pattern are still not definitely understood, intra- or even more likely postoperative loss of larger volumes of CSF seem to be related to this complication. Prognosis significantly depends on severity of hemorrhage and patient age. Outcome in more than 50% of all cases is good with only mild remaining neurological symptoms or complete recovery, while death occurs in approximately 10-15%. Close monitoring of patients undergoing surgery that involves the risk of draining large volumes of CSF is mandatory and patients with postoperative drainage of larger amounts of fluid acquire increased attentiveness. Early detection and correct interpretation of the typical bleeding pattern might help to avoid further aggravation of symptoms. This review will address incidence, typical appearance and pathophysiological considerations, as well as risk factors, treatment options, and outcome related with RCH.

Cerebellar hemorrhage after spinal surgery: case report and review of the literature

Recent reports indicate that cerebellar hemorrhage after spinal surgery is infrequent, but it is an important and preventable problem. This type of bleeding is thought to occur secondary to venous infarction, but the exact pathogenetic mechanisms are unknown. This report details the case of a 48-year-old woman who developed remote cerebellar hemorrhage after spinal surgery. The patient presented with a herniated lumbar disc, spinal stenosis, and spondylolisthesis, and underwent multiple-level laminectomy, discectomy, and transpedicular fixation. The dura mater was opened accidentally during the operation. There were no neurologic deficits in the early postoperative period; however, 12 h postsurgery the patient complained of headache. This became more severe, and developed progressive dysarthria and vomiting as well. Computed tomography demonstrated small sites of remote cerebellar hemorrhage in both cerebellar hemispheres. The patient was treated medically, and was discharged in good condition. At 6 months after surgery, she was neurologically normal. The case is discussed in relation to the ten previous cases of remote cerebellar hemorrhage documented in the literature. The only possible etiological factors identified in the reported case were opening of the dura and large-volume cerebrospinal fluid loss.

The microsurgical anatomy of the glossopharyngeal nerve with respect to the jugular foramen lesions

Removal of lesions involving the jugular foramen region requires detailed knowledge of the anatomy and anatomical landmarks of the related area, especially the lower cranial nerves. The glossopharyngeal nerve courses along the uppermost part of the jugular foramen and is well hidden in the deep layers of the neck, making this nerve is the most difficult one to identify during surgery. It may be involved in various pathological entities along its course. The glossopharyngeal nerve can also be compromised iatrogenically during the surgical treatment of such lesions. The authors define landmarks that can help identify this nerve during surgery and discuss the types of lesions that may involve each portion of the glossopharyngeal nerve.

Cerebellar hemorrhage as a complication of temporal lobectomy for refractory medial temporal epilepsy: report of three cases

Cerebellar hemorrhage is listed among the potential complications following neurosurgical pro ce dures. In this scenario it is usually reported as a rare condition. However, it seems that epilepsy surgery pa tients are somewhat more prone to this kind of complication, compared to other surgical groups. Head po si tioning, excessive cerebral spinal fluid draining and the excision of non-expanding encephalic tissue (or combinations among the three) are likely to be cause underlying remote cerebellar hemorrhage. Out of the 118 ATL/AH performed at our institution, between 1996 and 2002, we identified 3 (2.5%) patients pre sen ting with cerebellar hemorrhage. We report on such cases and review the literature on the topic.

Anatomic landmarks of the glossopharyngeal nerve: a microsurgical anatomic study

OBJECTIVE

Compared with other lower cranial nerves, the glossopharyngeal nerve (GPhN) is well hidden within the jugular foramen, at the infratemporal fossa, and in the deep layers of the neck. This study aims to disclose the course of the GPhN and point out landmarks to aid in its exposure.

METHODS

The GPhN was studied in 10 cadaveric heads (20 sides) injected with colored latex for microsurgical dissection. The specimens were dissected under the surgical microscope.

RESULTS

The GPhN can be divided into three portions: cisternal, jugular foramen, and extracranial. The rootlets of the GPhN emerge from the postolivary sulcus and course ventral to the flocculus and choroid plexus of the lateral recess of the fourth ventricle. The nerve then enters the jugular foramen through the uppermost porus (pars nervosa) and is separated from the vagus and accessory nerves by a fibrous crest. The cochlear aqueduct opens to the roof of this porus. On four sides in the cadaver specimens (20%), the GPhN traversed a separate bony canal within the jugular foramen; no separate canal was found in the other cadavers. In all specimens, the Jacobson's (tympanic) nerve emerged from the inferior ganglion of the GPhN, and the Arnold's (auricular branch of the vagus) nerve also consisted of branches from the GPhN. The GPhN exits from the jugular foramen posteromedial to the styloid process and the styloid muscles. The last four cranial nerves and the internal jugular vein pass through a narrow space between the transverse process of the atlas (C1) and the styloid process. The styloid muscles are a pyramid shape, the tip of which is formed by the attachment of the styloid muscles to the styloid process. The GPhN crosses to the anterior side of the stylopharyngeus muscle at the junction of the stylopharyngeus, middle constrictor, and hyoglossal muscles, which are at the base of the pyramid. The middle constrictor muscle forms a wall between the GPhN and the hypoglossal nerve in this region. Then, the GPhN gives off a lingual branch and deepens to innervate the pharyngeal mucosa.

CONCLUSION

Two landmarks help to identify the GPhN in the subarachnoid space: the choroid plexus of the lateral recess of the fourth ventricle and the dural entrance porus of the jugular foramen. The opening of the cochlear aqueduct, the mastoid canaliculus, and the inferior tympanic canaliculus are three landmarks of the GPhN within the jugular foramen. Finally, the base of the styloid process, the base of the styloid pyramid, and the transverse process of the atlas serve as three landmarks of the GPhN at the extracranial region in the infratemporal fossa.

Cerebellar haemorrhage following supratentorial craniotomy

Distant cerebellar haemorrhage is a rare complication occurring in approximately 0.3-0.6% of all supratentorial craniotomy. A Medline and Pubmed search revealed only 98 cases in the English literature. We report three cases from our institution. An overall review of these 101 cases demonstrated that this complication commonly presented early in the postoperative course as decreased level of consciousness following aneurysm repair surgery or lobectomy for epilepsy. Asymptomatic presentation due to small haemorrhage was not uncommon. A transtentorial pressure gradient set up by excessive CSF loss is generally held responsible for disrupting the cerebellar venous blood flow and consequently leading to venous haemorrhage. Perioperative hypertension may also play a role. The outcome of patients who survived the complications was generally good, though not infrequently fatality resulted from the mass effect of extensive cerebellar haemorrhage demanded vigilance in its management.

Cerebellar hemorrhage after spinal surgery: report of two cases and literature review

OBJECTIVE AND IMPORTANCE

Cerebellar hemorrhage remote from the site of surgery may complicate neurosurgical procedures. We describe our experience with two cases of cerebellar hemorrhage after spinal surgery and review the three cases previously reported in the literature to determine whether these cases provide insight regarding the pathogenesis of remote cerebellar hemorrhage.

CLINICAL PRESENTATION

One of our patients developed cerebellar hemorrhage in the vermis and right hemisphere after transpedicular removal of a partially intradural T9-T10 herniated disc with the patient in the prone position. The other patient developed cerebellar hemorrhage in the vermis and bilateral hemispheres after L3-S1 decompression and instrumentation with the patient in the prone position, during which the dura was inadvertently opened.

INTERVENTION

The first patient was treated conservatively and had mild residual dysarthria and gait ataxia 2 months after surgery. The second patient underwent exploration and revision of the lumbar wound with primary dural repair. The cerebellar hemorrhage was treated conservatively, and the patient had mild dysarthria and ataxia 1 month after surgery.

CONCLUSION

Cerebellar hemorrhage must be considered in patients with unexplained neurological deterioration after spinal surgery. Dural opening with loss of cerebrospinal fluid has occurred in every reported case of cerebellar hemorrhage complicating a spinal procedure, supporting the hypothesis that loss of cerebrospinal fluid is central to the pathogenesis of this condition. Because remote cerebellar hemorrhage can occur after procedures with the patient in the supine, sitting, and prone positions, patient positioning seems unlikely to play a causative role in its occurrence.

Remote cerebellar hemorrhage after supratentorial surgery

OBJECTIVE

Remote cerebellar hemorrhage (RCH) is an infrequent and poorly understood complication of supratentorial neurosurgical procedures. We retrospectively compared 42 patients who experienced RCH with a case-matched control cohort, to delineate risk factors associated with the occurrence of this complication.

METHODS

Between 1988 and 2000, 42 patients experienced RCH after supratentorial neurosurgical procedures at our institution. Diagnoses were made on the basis of postoperative computed tomographic or magnetic resonance imaging findings in all cases. The medical records for these patients were reviewed and compared with those for a control cohort of 43 patients, matched for age, sex, surgical lesion, and type of craniotomy, who were treated during the same period.

RESULTS

RCH most commonly occurred after frontotemporal craniotomies for unruptured aneurysm repair or temporal lobectomy and was frequently an incidental finding on postoperative computed tomographic scans. However, some cases of RCH were associated with significant morbidity, and two patients died. Preoperative aspirin use and elevated intraoperative systolic blood pressure were significantly associated with RCH (P = 0.026 and P = 0.036, respectively). Pathological findings for two cases demonstrated hemorrhagic infarctions in both.

CONCLUSION

RCH most commonly follows supratentorial neurosurgical procedures, performed with the patient in the supine position, that involve opening of cerebrospinal fluid cisterns or the ventricular system (such as unruptured aneurysm repair or temporal lobectomy). Preoperative aspirin use and moderately elevated intraoperative systolic blood pressure are potentially modifiable risk factors associated with the development of RCH. Although RCH can cause death or major morbidity, most cases are asymptomatic or exhibit a benign course. Cerebellar "sag" as a result of cerebrospinal fluid hypovolemia, causing transient occlusion of superior bridging veins within the posterior fossa and consequent hemorrhagic venous infarction, is the most likely pathophysiological cause of RCH.