Thromboembolic complications during and after embolization of unruptured aneurysms: A chronological outcome in periprocedural thromboembolic events.

Background: Ischemic complications develop after elective coil embolization procedures at a certain rate. The prevention of these events has been a longstanding issue for many interventional neuroradiologists. This study aimed to clarify whether procedural ischemic events after unruptured aneurysm embolization decrease over time with perioperative anti-thromboembolic treatment or surgical experience. Methods: This study included patients with cerebral aneurysms in our institution between July 2012 and June 2020. Dual-antiplatelet therapy (DAPT) was performed (Phase 1). Thromboembolic events developed at a certain rate; thus, rivaroxaban was administered with single-antiplatelet therapy (SAPT) to improve thromboembolic results (Phase 2), showing better outcomes than in Phase 1. Subsequently, DAPT was administered again (Phase 3). Ischemic complications were evaluated in each phase or compared between the DAPT group and the direct oral anticoagulant (DOAC) with the clopidogrel (DOAC+SAPT) group. Results: Relatively, fewer symptomatic ischemic events were noted in Phase 2 or the DOAC+SAPT group, but the outcome was not better in Phase 3 than in Phase 2. Symptomatic complications were more common in Phase 3 than in Phases 1 and 2. Conclusion: Ischemic complications occurred at a certain rate after endovascular procedures for unruptured aneurysms. The incidence did not decrease over time; particularly, standard DAPT plus postoperative anti-thromboembolic medication did not adequately decrease complications in Phase 3 compared to Phases 1 and 2. Therefore, accumulated experience or a learning curve could not explain the results. DOAC administration might decrease the risk of these events, but further accumulation of evidence or prospective investigation is warranted.

Subdural Hygroma After Management of Ruptured Intracranial Aneurysms: Incidence, Associated Factors, Clinical Course, and Management Options.

OBJECTIVE: To evaluate the incidence, associated factors, clinical course, and management options of subdural hygroma in patients treated for aneurysmal subarachnoid hemorrhage (aSAH). METHODS: From January 2013 until June 2022, 336 consecutive patients with aSAH underwent treatment in our center. No one patient was excluded from the study cohort. Computed tomography (CT) examinations were performed at admission, immediately after surgery and on the first postoperative day, and subsequently in case of any neurologic deterioration or, at least, once per week until discharge from the hospital. Thereafter, CT examinations were at the discretion of specialists in the rehabilitation facility, referring physicians, or neurosurgeons at the outpatient clinic. RESULTS: The length of radiologic follow-up starting from CT at admission ranged from 1 to 3286 days (mean, 673 ± 895 days; median, 150 days). Subdural hygromas developed in 84 patients (25%). An average interval until this imaging finding from the initial CT examination was 25 ± 55 days (median, 8 days; range, 0-362 days). Evaluation in the multivariate model showed that patient age ≥72 years (P < 0.0001), cerebrospinal fluid (CSF) shunting (P < 0.0001), and microsurgical clipping of ruptured intracranial aneurysm (RIA; P < 0.0001) are independently associated with the development of subdural hygroma. In 54 of 84 cases (64%), subdural hygromas required observation only. Increase of the lesion size with (5 cases) or without (10 cases) appearance of midline shift was associated with patient age <72 years (P = 0.0398), decompressive craniotomy (P = 0.0192), and CSF shunting (P = 0.0009), whereas evaluation of these factors in the multivariate model confirmed independent association of only CSF shunting (P = 0.0003). Active management of subdural hygromas included adjustment of the shunt programmable valve opening pressure, cranioplasty, external subdural drainage, or their combination. Overall, during follow-up (mean, 531 ± 824 days; median, 119 days; range, 2-3285 days) after the start of observation or applied treatment, subdural hygromas showed either decrease (50 cases) or stabilization (34 cases) of their sizes, and no one lesion showed progression again. CONCLUSIONS: The clinical course of subdural hygromas in patients treated for aSAH is generally favorable, but occasionally these lesions show progressive enlargement with or without the appearance of midline shift, which requires active management.

Appropriate treatment within 13 hours after onset may improve outcome in patients with high-grade aneurysmal subarachnoid hemorrhage.

OBJECTIVE: This retrospective study evaluated whether earlier timing of appropriate treatment of high-grade aneurysmal subarachnoid hemorrhage (aSAH), defined as management of ruptured intracranial aneurysm (RIA) combined with required additional surgical measures for control of increased intracranial pressure (ICP), is associated with more favorable outcomes. METHODS: The study cohort comprised 253 patients with high-grade aSAH. Modified Rankin Scale score of 0-3 at 3-month follow-up after the ictus was considered as favorable outcome. RESULTS: Appropriate treatment of aSAH was completed in 205 patients (81 %), and included clipping or coiling of RIA without (64 cases) and with (141 cases) additional surgical measures for control of increased ICP (evacuation of intracranial hematoma, decompressive craniotomy, and/or cerebrospinal fluid drainage). Favorable outcome was noted significantly more often if appropriate treatment was completed within 13 h after aSAH than between 13 and 72 h (37 % vs. 17 %; adjusted P = 0.0475), which was confirmed by evaluation in the multivariate model along with other prognostic factors. Subgroup analysis revealed that completion of the appropriate treatment within 13 h was associated with more favorable outcome in those patients, who underwent management of RIA in combination with additional surgical measures for control of increased ICP (P = 0.0023), and in those, who felt into poor outcome predicting group (P = 0.0046). CONCLUSIONS: Appropriate treatment of high-grade aSAH with management of RIA in combination with required additional surgical measures for control of increased ICP, may be associated with more favorable outcomes if completed within 13 h after the ictus.

Nonconvulsive status epilepticus as sign of tumor recurrence.

Status epilepticus (SE) can be a sign of brain tumor progression or recurrence, but there are few reports of nonconvulsive status epilepticus (NCSE) being a sign of tumor progression or recurrence. Moreover, much remains to be elucidated about its clinical course, and outcome. This is the first report of NCSE associated with the progression of a metastatic brain tumor treated by surgical excision of the tumor. The patient was 74-year-old woman. She had a history of craniotomy for tumor resection and gamma knife treatment for multiple metastatic brain tumors originating from breast cancer. She suddenly developed dysarthria and right hemiparesis, followed by convulsive seizures in the right side of her body. Magnetic resonance imaging showed tumor recurrence in the left parietal lobe and worsening edematous changes around the tumor. Antiseizure medication was initiated, however her seizures did not improve; therefore, tumor resection was performed. Postoperatively, her consciousness, seizures, and electroencephalogram findings improved. NCSE caused by brain tumors may be refractory to treatment with antiseizure medications, and early surgical treatment may be useful for seizure control.

Acute subdural hematoma associated with disruption of tumor vessels due to rapid growth of falx meningioma: A case report and literature review.

Background: Meningiomas associated with acute subdural hematoma (ASDH) are rare. The rapid growth of meningiomas has been shown to be one of the mechanisms underlying bleeding. We report the first case of ASDH during an imaging follow-up for the rapid growth of a falx meningioma. Case Description: A 77-year-old woman was diagnosed with an incidental tumor along the right falx cerebri 3 years before bleeding. The follow-up magnetic resonance imaging (MRI) after 3 years showed that the tumor volume had rapidly increased from 4.31 cm3 to 22.27 cm3. The blood vessels around the tumor were stretched. The patient was scheduled to undergo tumor removal surgery. However, the patient experienced a sudden onset of disturbance of consciousness and was transferred to our hospital. On arrival, her Glasgow Coma Scale (GCS) score was 6 (E1V1M4) and right hemiplegia was observed. The patient had no history of traumatic events. Computed tomography (CT) showed left hemispheric and interhemispheric ASDH. Digital subtraction angiography revealed neither tumor staining nor abnormal vessels. Gross total tumor removal and hematoma evacuation were performed. There were no obvious active intraoperative bleeding points. The pathologic diagnosis was meningioma, the World Health Organization Grade I. Postoperative course revealed a GCS score of 10 (E4V1M5) and she was transferred to a rehabilitation hospital. Conclusion: The disruption of tumor vessels due to the rapid growth of meningiomas may be a cause of bleeding. Incidental falx meningiomas with stretched tumor vessels due to rapid growth could indicate the need for early surgery.

Venous Flow Conversion Technique for Sacrificing the Superior Petrosal Vein During Microvascular Decompression for Trigeminal Neuralgia.

BACKGROUND: Microvascular decompression for trigeminal neuralgia (TN) may require sacrifice of the superior petrosal vein (SPV), with potential risks of ischemia and hemorrhagic complications due to impaired venous return. OBJECTIVE: To investigate methods for safely sacrificing the SPV. METHODS: We retrospectively reviewed 21 cases in 346 consecutive microvascular decompression surgeries for TN. They were intraoperatively identified as SPV and its tributaries being the offending vessels causing TN and were intentionally sacrificed. RESULTS: The transverse pontine vein (TPV) was sacrificed in 10 patients. The main trunk of the SPV was sacrificed using the TPV as a collateral flow pathway in 10 patients. No complications occurred related to impaired venous return. CONCLUSION: The venous flow conversion technique can be applied to safely sacrificing the SPV and its tributaries with the TPV acting as a collateral blood flow pathway to prevent postoperative impaired venous return.

Preoperative plasma D-dimer level may be predictive for success of cerebral reperfusion and outcome after emergency mechanical thrombectomy for intracranial large vessel occlusion.

Presented retrospective analysis evaluated whether preoperative plasma D-dimer level may predict the success of cerebral reperfusion and outcome after emergency mechanical thrombectomy (MT) for intracranial large vessel occlusion (ILVO). Study cohort comprised 121 patients (mean age, 76 ± 12 years) from two participating centers. ILVO mostly affected the M1 segment (48 cases) and internal carotid artery (ICA; 37 cases). Mean preoperative National Institutes of Health Stroke Scale (NIHSS) score was 18 ± 8. Mean preoperative plasma D-dimer level was 4.4 ± 6.6 µg/ml. In 88 patients (73%) MT resulted in successful cerebral reperfusion. Multivariate analysis revealed independent associations of non-successful cerebral reperfusion with preoperative plasma D-dimer level > 6.7 µg/ml (P = 0.0021), location of ILVO other than ICA (P = 0.0056), and prolonged antiplatelet or anticoagulant therapy before stroke onset (P = 0.0172). Plasma D-dimer level ≤ 6.7 µg/ml predicted successful cerebral reperfusion with 0.91 sensitivity and 0.36 specificity. In 39 patients (32%) treatment resulted in favorable outcome. Multivariate analysis revealed independent associations of the unfavorable outcome with non-successful cerebral reperfusion after MT (P = 0.0005), preoperative plasma D-dimer level > 1.9 µg/ml (P = 0.0131), higher preoperative NIHSS score (P = 0.0171), and chronic arterial hypertension before stroke onset (P = 0.0254). Plasma D-dimer level ≤ 1.9 µg/ml predicted favorable outcome with 0.64 sensitivity and 0.62 specificity. In conclusion, preoperative plasma D-dimer level may be predictive for success of cerebral reperfusion and outcome after emergency MT for ILVO, which may be potentially helpful for prediction of prognosis in selected treatment candidates.

Short-Vessel Occlusion Might Indicate Higher Possibility of Success in Reperfusion following Mechanical Thrombectomy in Acute Middle Cerebral Artery Occlusion.

BACKGROUND: The impact of the length of the occluded vessel in acute large-vessel occlusion on successful reperfusion by mechanical thrombectomy remains unclear. This study evaluated whether diameter and length of the occluded vessel in acute middle cerebral artery (MCA) occlusion might relate to successful reperfusion following mechanical thrombectomy. METHODS: This retrospective study included patients with acute MCA occlusion who underwent intra-aortic injection of contrast medium to obtain maximum intensity projection (MIP) images acquired by flat-panel detector computed tomography (FD-CT) equipped with an angiographic system. All patients received mechanical thrombectomy and were divided into two groups: those with successful reperfusion (Thrombolysis in Cerebral Infarction [TICI] 2b/3) and those without. We compared the diameter and length of the occluded vessel between the groups. In the sub-analysis of patients with stent retriever use, ratio of length of occluded vessel to length of the active zone was compared. RESULTS: We enrolled 29 patients (median age: 73, M1 occlusion: 51%, stent retriever use: 72%). Eighteen patients achieved TICI 2b/3 with significantly larger distal end diameter (1.7 [interquartile range: 1.5-1.9] vs. 1.2 [1.2-1.5] mm, p = 0.007) and shorter length (7.1 [4.9-9.7] vs. 12.3 [7.2-15.8] mm, p = 0.043) of the occluded vessel. Sub-analysis of 21 patients showed that the cut-off value for TICI 2b/3 reperfusion was 0.32 as the ratio between the occluded vessel and stent retriever active zone (receiver operating characteristic area under the curve: 0.90). CONCLUSION: In acute MCA occlusion, larger diameter of the distal end and shorter length of the occluded vessel on FD-CT MIP images might indicate a higher possibility of achieving TICI 2b/3 following mechanical thrombectomy.

Cerebral vasospasm and hypoperfusion after traumatic brain injury: Combined CT angiography and CT perfusion imaging study.

BACKGROUND: Timely identification of the cerebral perfusion abnormalities after traumatic brain injury (TBI) is highly important. The objective of this study was the evaluation of the post traumatic vasospasm and cerebral hypoperfusion with the serial combined CT angiography (CTA) and CT perfusion (CTP) imaging examinations. METHODS: The case series comprised 25 adult patients with closed TBI accompanied by various types of intracranial hematoma. Emergency surgery was done in 15 cases (60%). Combined CTA and CTP were performed on days 0 (D0) and 7 ± 1 (D7) after trauma. RESULTS: CTA on D0 did not demonstrate vasospasm in any case but revealed it on D7 in 9 patients (36%). In the multivariate analysis, only the presence of subarachnoid hemorrhage (SAH) on D7 had confirmed a significant association with the development of vasospasm (P = 0.0201). Cerebral hypoperfusion at least in one evaluated brain region was noted on D0 and D7 in 76% and 60% of patients, respectively, and showed highly variable spatial distribution and temporal development. Treatment results were not associated with the presence of vasospasm (P = 0.7337) or the number of brain regions affected by hypoperfusion on D0 (P = 0.2285), but the number of brain regions affected by hypoperfusion on D7 was significantly greater in cases of unfavorable outcome (P = 0.0187). CONCLUSION: Vasospasm is merely related to SAH sustained at the subacute stage of TBI, but its spatial and temporary interrelationships with the post traumatic cerebral hypoperfusion are complex. Serial combined CTA and CTP examinations may facilitate monitoring of perfusion abnormalities and treatment guidance.

Resolution of the large middle fossa arachnoid cyst without any identifiable cause: Case report.

Although the possibility of spontaneous regression of intracranial arachnoid cysts (AC) during observational follow-up is widely recognized, the number of reports documenting such clinical course, often associated with the mild head trauma, is rather limited. We present a case of nearly complete resolution of the large middle fossa AC in a 5-year-old boy without any identifiable cause in 2.3 years after the initial diagnosis. It once again justifies observational strategy for AC not accompanying by mass effect and manifesting with minimal symptoms or diagnosed incidentally.

Optimal timing and safety of the external ventricular drainage in patients with high-grade aneurysmal subarachnoid hemorrhage treated with endovascular coiling.

The presented retrospective analysis has evaluated the optimal timing and safety of external ventricular drainage (EVD) for acute hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH). The study cohort comprised 102 patients, 49 of whom underwent EVD at 3-120 h (mean, 16 h) after the clinical onset of aSAH, either before (N = 27) or after (N = 22) ruptured aneurysm coiling. Among those treated with EVD, favorable and fair outcomes at discharge (modified Rankin Scale [mRS] scores 0-3) were noted in 14 (29%) and unfavorable (mRS scores 4-6) in 35 (71%). The former was more common among women (P = 0.019) and patients without chronic arterial hypertension (P = 0.028). The cut-off value for optimal timing of EVD was defined at 13 h after the onset of aSAH. Favorable and fair outcomes were more frequent after early (≤13 h; N = 30) than late (>13 h; N = 19) EVD (40% vs. 11%; P = 0.026), whereas did not differ significantly between those in whom such procedure was done before or after ruptured aneurysm coiling (19% vs. 41%; P = 0.083). In the entire study cohort, 2 patients had re-rupture of the aneurysm, and while both of them were treated with EVD, neither case of complication was directly associated with the procedure and, in fact, preceded it. In conclusion, EVD for management of acute hydrocephalus in patients with high-grade aSAH should be preferably applied within 13 h after the clinical onset of stroke, which may be considered sufficiently safe regardless whether it is performed before or after ruptured aneurysm coiling.

Characteristics and management of the offending veins in microvascular decompression surgery for trigeminal neuralgia.

The optimal technique of microvascular decompression (MVD) for trigeminal neuralgia (TN) caused by venous conflict remains unclear. The objectives of this study are to characterize the offending veins identified during MVD for TN and to evaluate intraoperative technique applied for their management. From 2007 till 2019, 308 MVD surgeries were performed in 288 consecutive patients with TN, and in 58 of them, pure venous conflict was identified. In 44 patients, the offending vein was interrupted, as was done for small veins arising from the cisternal trigeminal nerve (CN V) or its root entry zone (REZ) causing their stretching (19 cases), small veins on the surface of REZ (9 cases), transverse pontine vein (TPV) compressing REZ or distal CN V (12 cases), and superior petrosal vein (SPV) using flow conversion technique (4 cases). In 14 other cases, the offending vein was relocated, as was done for the SPV or the vein of cerebellopontine fissure (8 cases), TPV (3 cases), and the vein of middle cerebellar peduncle (3 cases). Complete pain relief after surgery was noted in 49 patients (84%). No one patient experienced major neurological deterioration. Postoperative facial numbness developed in 14 patients (24%), and in 8 of them, it was permanent. In 14 patients, MRI demonstrated venous infarction of the middle cerebellar peduncle, which was associated with the presence of any (P = 0.0180) and permanent (P = 0.0002) facial numbness. Ten patients experienced pain recurrence. Thus, 39 patients (67%) sustained complete pain relief at the last follow-up (median, 48 months), which was significantly associated with the presence of any (P = 0.0228) and permanent (P = 0.0427) postoperative facial numbness. In conclusion, in cases of TN, small offending veins arising from REZ and/or distal CN V and causing their stretching may be coagulated and cut. In many cases, TPV can be also interrupted safely or considered as collateral way for blood outflow. The main complication of such procedures is facial numbness, which is associated with the venous infarction of middle cerebellar peduncle and long-term complete pain relief.

Successful Mechanical Thrombectomy for Subocclusive Thrombus at the Origin of Lenticulostriate Artery.

Optimal treatment of patients with intracranial subocclusive thrombus remains unclear. Such a rare case successfully managed with endovascular mechanical thrombectomy is presented. A 71-year-old man experienced a sudden onset of dysarthria and motor deficits. At the time of admission his National Institutes of Health Stroke Scale (NIHSS) score was 4. DWI demonstrated incomplete infarction within the left lenticulostriate artery (LSA) territory, MRA showed partial flow defect in the distal left M1 segment and non-visualization of the LSA, and ECG revealed atrial fibrillation, thus ischemic stroke caused by cardiogenic embolism was diagnosed. Tissue plasminogen activator was administered, but symptoms progressed and NIHSS score increased up to 8. Diagnostic angiogrpahy confirmed presence of the subocclusive thrombus within the distal left M1 segment and complete occlusion of LSA at its origin. Since conservative therapy was ineffective, mechanical thrombectomy utilizing ADAPT (a direct aspiration first-pass thrombectomy) technique was performed resulting in compete recanalization of the LSA accompanied by the prompt regress of neurological symptoms. Eventally, the patient demonstrated nearly full recovery (modified Rankin Scale score 1). Thus, mechanical thrombectomy should be considered as a reasonable option in cases of acute cerebral stroke caused by subocclusive thrombus and progressive neurological deficits despite standard conservative therapy. J. Med. Invest. 67 : 372-374, August, 2020.

Aggressive internal and external decompression as a life-saving surgery in a deeply comatose patient with fixed dilated pupils after severe traumatic brain injury: A case report.

BACKGROUND: To maximize control of the intracranial pressure in deeply comatose patients with malignant cerebral swelling, combination of the surgical techniques for internal and external brain decompression may be reasonable, as demonstrated in the presented case. CASE DESCRIPTION: A 55-year-old man was admitted with Glasgow Coma Scale (GCS) score 4, maximally dilated pupils, and absence of the pupillary light and vestibulo-ocular reflexes. Head CT revealed massive acute subdural hematoma, prominent brain shift with subfalcine and transtentorial herniation, and diffuse subarachnoid hemorrhage. Large size decompressive craniectomy and evacuation of subdural hematoma were done, however, prominent swelling of the brain and its protrusion through the bone defect remained. Therefore, extensive temporal lobectomy and removal of the bulk of temporal muscle were additionally attained followed by lax duraplasty. Gradual recovery of the patient was noted from the 1st postoperative day, and on the 70th day, his GCS score was 4T4. Three months later, his condition corresponded to the Glasgow Outcome Scale score 3 (severe disability). CONCLUSION: Aggressive internal and external decompression with combination of large size craniectomy, extensive temporal lobectomy, removal of the bulk of temporal muscle, and lax duraplasty should be considered as possible life-saving option in cases of neurosurgical emergencies with malignant cerebral swelling.

Risk of Intracranial Hemorrhage and Short-Term Outcome in Patients with Minor Head Injury.

OBJECTIVE: To examine the occurrence of traumatic intracranial hemorrhage (tICH) and outcome in patients with minor head injury and assess the probable risk factors. METHODS: Patients with minor head injury who visited our hospital from January 2015 to July 2017 were registered consecutively, and enrolled patients were aged ≥18 years, visited within 24 hours of the injury, and had a Glasgow Coma Scale score of 15 at outpatient clinic or before the injury. RESULTS: Of the 1122 enrolled patients, 55 (4.9%) had tICH. An antiplatelet agent was administered in 114 patients, an anticoagulant agent was administered in 49 patients, and none of them were administered in 948 patients. A multivariate analysis of tICH identified it as a risk factor, showing significant difference between antiplatelet medication (P = 0.0312), fall from stairs (P = 0.0057), traffic accident (P = 0.0117), neurologic symptoms (P = 0.0091), and modified Rankin Scale (mRS) score before trauma (P < 0.0001). We also analyzed association of enlargement of tICH with different parameters and only anticoagulant medication indicated an increased risk (P = 0.0005). Thirty patients (2.6%) were dependent or died at discharge (mRS 3-6). The mRS score before trauma (P < 0.0001), tICH (P < 0.0001), spinal injury (P < 0.0001), and enlargement of intracranial hemorrhage (P = 0.0008) indicated an increased probability of morbidity (mRS 3-6) in multivariate analysis. CONCLUSIONS: Antiplatelet and anticoagulant medications were risk factor for tICH and enlargement of tICH in patients with minor head injury, respectively. A pretrauma condition of disability/dependence is an important risk factor for tICH and outcome.

Twelve-year single critical care center experience of nicardipine prolonged-release implants in patients with subarachnoid hemorrhage: a propensity score matching analysis.

OBJECTIVE: To develop a nicardipine prolonged-release implant (NPRI) to prevent cerebral vasospasm in patients with subarachnoid hemorrhage in 1999, which may be used during craniotomy, and report the results of our recent 12-year single critical care center experience. METHODS: Of 432 patients with aneurysmal subarachnoid hemorrhage treated between 2007 and 2019, 291 were enrolled. 97 Patients were aged >70 years (33%), 194 were female (67%), 138 were World Federation of Neurological Societies grades 1, 2, and 3 (47%), 218 were Fisher group 3 (75%), and 243 had an anterior circulation aneurysm (84%). Using a propensity score matching method for these five factors, the severity of cerebral vasospasm, occurrence of delayed cerebral infarction, and modified Rankin Scale (mRS) score at discharge were analyzed. RESULTS: One hundred patients each with or without NPRI were selected, and the ratios of coil/clip were 0/100 and 88/12, respectively. Cerebral vasospasm and delayed cerebral infarction were both significantly less common in the NPRI group (p=0.004, OR=0.412 (95% CI 0.223 to 0.760) and p=0.005, OR=0.272 (95% CI 0.103 to 0.714, respectively); a significant difference was seen in the mRS score at discharge by Fisher's exact test (p=0.0025). A mRS score of 6 (dead) was less common in the group with NPRI, and mRS scores of 0 and 1 were also less common. No side effects were seen. CONCLUSIONS: NPRIs significantly reduced the occurrence of cerebral vasospasm and delayed cerebral infraction without any side effects. The NPRI and non-NPRI groups showed different patterns of short-term outcomes in the single critical care center, which might have been due to selection bias and patient characteristics. Differences in outcomes may become clear in comparisons with patients treated by craniotomy.

Hemifacial Spasm Caused by Veins Confirmed by Intraoperative Monitoring of Abnormal Muscle Response.

BACKGROUND: Hemifacial spasm (HFS) is a benign disease caused by the hyper excitement of facial nerves owing to vessel compression. The offending vessels are usually arteries, such as anterior and posterior inferior cerebellar or vertebral arteries, but there are few reports of vein involvement cases. OBJECTIVE: The aim of this study was to investigate veins as offending vessels in patients with HFS confirmed by abnormal muscle response (AMR). METHODS: We analyzed 5 patients with HFS caused by veins among 78 patients with HFS over the past 10 years. All patients underwent microvascular decompression (MVD) with AMR monitoring, whereas 3 of them underwent a second MVD. The mean follow-up time was 97 months. RESULTS: Arteries were thoroughly decompressed in 3 patients with a failed first MVD surgery who received a second surgery, during which veins at the root exit point (RExP) were decompressed with the disappearance or a significant decrease in the amplitude of AMR. Two patients showed spasm resolution after the first surgery when veins were decompressed together with the disappearance of AMR. The location of veins was RExP and the cisternal portion. All patients had excellent outcomes within 3 months, and no complications were observed. CONCLUSIONS: Veins can be offending vessels in HFS patients. AMR is useful to determine the endpoint in these cases. Once arteries are decompressed thoroughly with residual AMR, surrounding veins at unusual sites, such as the RExP or the cisternal portion, must be checked to prevent persistent HFS. Complete decompression of veins leads to a good clinical outcome.

Nonspastic hemifacial spasm confirmed by abnormal muscle responses.

BACKGROUND: Hemifacial spasm is usually diagnosed by inspection which mainly identifies involuntary movements of orbicularis oculi. Assessing abnormal muscle responses (AMR) is another diagnostic method. CASE DESCRIPTION: We report a case of left hemifacial spasm without detectable involuntary facial movements. The patient was a 48-year-old man with a long history of subjective left facial twitching. On magnetic resonance imaging (MRI), the left VIIth cranial nerve was compressed by the left anterior inferior cerebellar artery (AICA), which was in turn compressed by the left vertebral artery. We initially treated him with botulinum toxin. We were able to record AMR, and hemifacial spasm occurred after AMR stimulation, although no spasm was detectable by inspection. Subsequently, we performed microvascular decompression with transposition of the AICA that compressed the VIIth cranial nerve. His hemifacial spasm resolved by 5 weeks after surgery and was not induced by AMR stimulation. CONCLUSION: Hemifacial spasm can sometimes be diagnosed by detecting AMR rather than by visual inspection. We propose that such hemifacial spasm should be termed nonspastic hemifacial spasm.

Microvascular decompression for hypoglossal nerve palsy secondary to vertebral artery compression: A case report and review of the literature.

BACKGROUND: Neurovascular-compression syndrome (NCS) is described as a prominent pathological contact between cranial nerves and vessels. Trigeminal neuralgia, hemifacial spasm, and glossopharyngeal neuralgia are typical clinical entities associated with NCS. On the other hand, the hyoglossal nerve is rarely affected by NCS. CASE DESCRIPTION: We present a case of hypoglossal nerve palsy (HNP) secondary to vertebral artery (VA) compression. A 47-year-old man presented to our hospital with a 1-month history of dysarthria and dysphagia. Neurological examination revealed left HNP, with an intact swallowing reflex and no oropharyngeal or palatal weakness. Magnetic resonance imaging (constructive interference in steady state) revealed left hypoglossal nerve compression by the V4 segment of the left atherosclerotic VA. He underwent microvascular decompression (MVD) surgery. Intraoperatively, the VA was compressing the hypoglossal nerve. The left VA was moved and attached to the dura matter using a polytetrafluoroethylene (Teflon®) sheet and fibrin glue. Postoperatively, the patient exhibited gradual recovery of HNP in 3 months without dysfunction of lower cranial nerves. CONCLUSION: In patients with isolated HNP, vascular compression should be considered as a cause of these symptoms, and subsequent MVD can lead to resolution.