Mechanical thrombectomy for cerebrovascular occlusion in a patient with situs inversus.

Situs inversus is a rare congenital abnormality characterized by mirror-image transposition of the major visceral organs and vessels. Few reports have discussed the use of mechanical thrombectomy in acute ischemic stroke with situs inversus. We present such a case, to raise awareness and deepen the knowledge on these cases. A 44-year-old man was admitted to our hospital with sudden-onset dysarthria and left-sided paresis. Computed tomography (CT) angiography revealed situs inversus and occlusion in the internal carotid artery. First, intravenous tissue plasminogen activator was administered, followed by immediate reperfusion with mechanical thrombectomy. We achieved thrombolysis in cerebral infarction grade 3. After the procedure, the patient fully recovered. Prompt diagnosis is crucial for rapid recanalization in patients with vascular anomalies such as situs inversus.

Risk of Bone Wax Migration During Retrosigmoid Craniotomy for Microvascular Decompression: Case-Control Study.

BACKGROUND AND OBJECTIVES: Bone wax is a flexible hemostatic agent commonly used for surgery in the posterior cranial fossa to control bleeding from the mastoid emissary vein. A large amount of bone wax can migrate into the sigmoid sinus through the mastoid emissary canal (MEC). We aimed to identify clinical factors related to intraoperative bone wax migration through the MEC during microvascular decompression (MVD) surgery, which may result in sigmoid sinus thrombosis. METHODS: We retrospectively collected the clinical data of patients with trigeminal neuralgia, hemifacial spasm, or trigeminal neuralgia accompanied by painful tic convulsif who underwent MVD. Basic information and the residual width and length (from the bone surface to the sigmoid sinus) of the MEC on computed tomography images were collected. We compared the collected clinical data between 2 groups of cases with and without intraoperative bone wax migration in the sigmoid sinus. RESULTS: Fifty-four cases with intraoperative bone wax migration and 187 patients without migration were enrolled. The t -test revealed significant differences in the width and length of the MEC ( P = .013 and P = .003, respectively). These variables were identified as significant factors in predicting intraoperative bone wax migration using multivariate logistic regression analysis. CONCLUSION: The large size of the MEC may be related to intraoperative bone wax migration into the sigmoid sinus in MVD. Neurosurgeons should be aware of these risks. Bone wax should be applied appropriately and hemostasis should be considered to control bleeding from the mastoid emissary vein in patients with a large MEC.

Functionality and Usability of the Exoscope in Microvascular Decompression for Hemifacial Spasm and Trigeminal Neuralgia.

BACKGROUND: Studies on the functionality and usability of the exoscope in neurosurgical procedures against surgical microscopes (SMs) are limited. This study aimed to examine the functionality and usability of the exoscope during microvascular decompression (MVD) surgery. METHODS: Seven neurosurgeons evaluated the usefulness of a 4 K, 3-dimension digital exoscope in MVD by answering a questionnaire. The questionnaire inquired about the functionality and usability of the exoscope by utilizing a visual analog scale (VAS; 1-10). A score of 5 on VAS was equivalent to the corresponding quality of the SM. The learning effect of the exoscope was evaluated using mean VAS scores in the first and last 3 cases for each neurosurgeon. RESULTS: The functionality of the exoscope in MVD was superior to that in SM (P < 0.001). In the last 3 surgeries, the mean VAS scores of the exoscope were excellent in terms of ease of arm handling, exchange of surgical instruments, ease of surgical procedure, and intraoperative physical stress. The mean VAS scores of the exoscope in intraoperative asthenopia were significantly higher than those of the SM (P < 0.001). No statistical significance was found in operation time, discharge outcome, and 1-year post-surgery outcome between MVD performed using the exoscope and SM. CONCLUSIONS: Neurosurgeons may experience reduced stress levels during MVD when using the exoscope. As the outcome of MVD using the exoscope did not demonstrate a statistical difference compared with MVD using the SM, the exoscope may prove to be a useful tool for performing MVD.

Cerebral proliferative angiopathy depicted by four-dimensional computed tomographic angiography: A case report.

Cerebral proliferative angiopathy is a rare cerebrovascular disorder characterized by diffuse abnormal vessels with intermingled brain parenchyma fed by many arteries and draining into many veins without high-flow arteriovenous shunts, which is usually confirmed by conventional digital subtraction angiography. However, dilution of the contrast medium due to the markedly increased blood flow and volume in cerebral proliferative angiopathy leads to low-contrast angiography. We report a 53-year-old man with cerebral proliferative angiopathy who underwent CT, MR imaging, MR angiography, digital subtraction angiography and 4D-CTA. The 4D-CTA exhibited abnormal vessels without early venous filling between the atrophic brain parenchyma in higher contrast than the angiography due to high spatial and time resolution, whereas the left external carotid angiography visualized the characteristic transdural supply more clearly than the 4D-CTA due to high vascular selectivity. Therefore, novel 4D-CTA and conventional angiography plays a complementary role in the accurate diagnosis of cerebral proliferative angiopathy. Taking invasiveness into account, 4D-CTA may be advantageous for the diagnosis of cerebral proliferative angiopathy based on the characteristic imaging findings.

Acute Brainstem Dysfunction Caused by Cavernous Sinus Dural Arteriovenous Fistula.

Symptoms of cavernous sinus dural arteriovenous fistula depend on the drainage patterns and are very diverse. Among these, brainstem dysfunction is a rare but serious complication. Here, we describe a case with isolated and rapidly progressive brainstem dysfunction due to cavernous sinus dural arteriovenous fistula. An 80-year-old woman presented with a 2-day history of progressive gait disturbance. Neurological examination revealed mild confusion, dysarthria, and left hemiparesis. Magnetic resonance imaging (MRI) revealed pontine swelling without evidence of infarction. Magnetic resonance angiography suggested a faint abnormality near the cavernous sinus. Dural arteriovenous fistula was suspected, and digital subtraction angiography was planned for the next day. Her condition had progressed to coma by the next morning. Pontine swelling worsened, and hyperintensity appeared on diffusion-weighted imaging. Digital subtraction angiography revealed a right-sided cavernous sinus dural arteriovenous fistula with venous reflux into the posterior fossa. Orbital or ocular symptoms had preceded brainstem symptoms in all nine previously reported cases, but brainstem symptoms were the only presentation in our case, making the diagnosis difficult. Some dural arteriovenous fistulas mimic inflammatory diseases when the clinical course is acute. Prompt diagnosis using enhanced computed tomography or MRI and emergent treatment are needed to avoid permanent sequelae.

Bridging veins and veins of the brainstem in microvascular decompression surgery for trigeminal neuralgia and hemifacial spasm.

OBJECTIVE In microvascular decompression surgery for trigeminal neuralgia and hemifacial spasm, the bridging veins are dissected to provide the surgical corridors, and the veins of the brainstem may be mobilized in cases of venous compression. Strategy and technique in dissecting these veins may affect the surgical outcome. The authors investigated solutions for minimizing venous complications and reviewed the outcome for venous decompression. METHODS The authors retrospectively reviewed their surgical series of microvascular decompression for trigeminal neuralgia and hemifacial spasm in patients treated between 2005 and 2017. Surgical strategies included preservation of the superior petrosal vein and its tributaries, thorough dissection of the arachnoid sleeve that enveloped these veins, cutting of the inferior petrosal vein over the lower cranial nerves, and mobilization or cutting of the veins of the brainstem that compressed the nerve roots. The authors summarized the patient characteristics, operative findings, and postoperative outcomes according to the vascular compression types as follows: artery alone, artery and vein, and vein alone. They analyzed the data using chi-square and 1-way ANOVA tests. RESULTS The cohort was composed of 121 patients with trigeminal neuralgia and 205 patients with hemifacial spasm. The superior petrosal vein and its tributaries were preserved with no serious complications in all patients with trigeminal neuralgia. Venous compression alone and arterial and venous compressions were observed in 4% and 22%, respectively, of the patients with trigeminal neuralgia, and in 1% and 2%, respectively, of those with hemifacial spasm (p < 0.0001). In patients with trigeminal neuralgia, 35% of those with artery and venous compressions and 80% of those with venous compression alone had atypical neuralgia (p = 0.015). The surgical cure and recurrence rates of trigeminal neuralgias with venous compression were 60% and 20%, respectively, and with arterial and venous compressions the rates were 92% and 12%, respectively (p < 0.0001, p = 0.04). In patients with hemifacial spasm who had arterial and venous compressions, their recurrence rate was 60%, and that was significantly higher compared to other compression types (p = 0.0008). CONCLUSIONS Dissection of the arachnoid sleeve that envelops the superior petrosal vein may help to reduce venous complications in surgery for trigeminal neuralgia. Venous compression may correlate with worse prognosis even with thorough decompression, in both trigeminal neuralgia and hemifacial spasm.

Indocyanine Green Videoangiography for Surgery of a Ruptured Dissecting Aneurysm in the Precommunicating Anterior Cerebral Artery: A Technical Case Report.

BACKGROUND AND IMPORTANCE: Indocyanine green videoangiography (ICG-VA) is an important intraoperative adjunct for saccular aneurysm surgery, but its efficacy in surgery for dissecting aneurysms has rarely been reported. The authors describe the usefulness of preclipping ICG-VA in a rare case of a ruptured dissecting aneurysm located at the precommunicating (A1) segment of the anterior cerebral artery. CLINICAL PRESENTATION: A 52-year-old woman, with no history of connective tissue diseases or vascular disorders, presented with sudden headache and convulsion. The CT scan showed that the patient had subarachnoid hemorrhage. Angiography showed a dissecting aneurysm in the left A1 segment of the anterior cerebral artery. Thus, the patient underwent trapping of the dissecting aneurysm. ICG-VA was used as an intraoperative adjunct before and after clipping. The preclipping ICG-VA showed the heterogeneously bright dissecting aneurysm and branching arteries even in the presence of hematoma. CONCLUSION: Preclipping ICG-VA may enhance the advantage of direct surgery for dissecting aneurysm by allowing visualization of the extent of the dissected vascular wall and the related branching arteries. ICG-VA can be an indispensable adjunct to minimize the compromise from the surgical treatment for intracranial dissecting aneurysms.

[Treatment of Non-Traumatic Spinal Epidural Hematoma:A Report of Five Cases and a Systematic Review of the Literature].

Objective:Non-traumatic spinal epidural hematoma(SEH)is relatively rare. We report five cases of SEH, review the relevant literature, and discuss the current treatment strategies for non-traumatic SEH in Japan. Methods:Clinical data of cases with non-traumatic SEH treated at our institute from 2008 to 2015 were retrospectively analyzed. In addition, we identified the relevant literature using the Japan Medical Abstracts Society databases for peer-reviewed articles published from Jan 1, 1995 to Aug 31, 2015. The search terms "spinal", "epidural hematoma", and "non-traumatic OR spontaneous" were used. Treatment strategies were summarized according to the treatment criteria. Results:Five patients(1 man and 4 women;age, 59-86 years;mean age, 74 years)were treated for SEH. Hematomas were located in the cervical(n=1), cervicothoracic(n=2), thoracic(n=1), and thoracolumbar(n=1)regions. All patients suffered sudden neck and/or back pain followed by subsequent neurological deterioration. Four patients were under antithrombotic treatment, and underwent laminectomy and drainage of the hematoma due to severe and progressive neurological deficits. All patients demonstrated significant neurological recovery. Seventy-seven articles from domestic institutes and hospitals were identified. Their criteria for conservative and surgical treatments differed based on the time from the onset and severity. Conclusion:Five cases of non-traumatic SEH were treated successfully. Patients with moderate to severe neurological deficit need timely surgical management, while non-surgical treatment may be indicated in mild deficits. To standardize the optimal treatment for non-traumatic SEH, an appropriate assessment system incorporating the time from onset and severity of neurological impairment should be established.