Maximum Nidus Depth as a Risk Factor of Surgical Morbidity in Eloquent Brain Arteriovenous Malformations.

BACKGROUND: Eloquent location of a brain arteriovenous malformation (BAVM) is known to increase the surgical risk. Surgical removal of such BAVMs is challenging. Useful indicators for the safe removal of eloquent BAVMs are needed. The aim of this study was to determine the surgical risk factors for these challenging entities. METHODS: The authors retrospectively reviewed 29 motor and/or sensory BAVM patients who underwent surgeries. The risk factors for surgical morbidity were analyzed. As a new risk factor, maximum nidus depth, was evaluated. RESULTS: Complete obliteration was achieved in 28 patients (96.6%). Postoperative transient and permanent neurological deteriorations were seen in nine patients (31.0%) and five patients (17.2%), respectively. In univariate analysis, maximum nidus depth (p = 0.0204) and asymptomatic onset (p = 0.0229) were significantly correlated with the total morbidity. In multivariate analysis, only maximum nidus depth was significantly correlated with total morbidity (p = 0.0357; odds ratio, 2.78598; 95% confidence interval, 0.8866-8.7535). The cut-off value for the maximum nidus depth was 36 mm for total morbidity (area under the curve [AUC], 0.7428) and 41 mm for permanent morbidity (AUC, 0.8833). The cutoff value of the maximum nidus size was 30 mm for total morbidity (AUC, 0.5785) and 30 mm for permanent morbidity (AUC, 0.7625). AUC was higher for the maximum nidus depth than it was for the maximum nidus size. CONCLUSIONS: Maximum nidus depth was significantly associated with surgical morbidity of eloquent BAVMs. The maximum nidus depth is a novel and a simpler indicator of the risk of surgical morbidity.

[High Parietal Paramedian Approach for Tumors in the Trigone of the Lateral Ventricle:Technical Nuances and Case Review].

The aim of this paper was to introduce and validate our high parietal paramedian approach for tumors in the trigone of the lateral ventricles. This study included nine tumors found in the trigone region and treated surgically in our institute. The approach of this method is described here. First, the central sulcus and post-central gyrus were identified by the electrodes after opening of the dura mater. Corticotomy was performed in the rearward area of the post-central gyrus 25mm within the midline and 20mm along the length, to avoid the damage to the primary sensory area and arcuate fasciculus. A round-shaped spatula was used to protect the surrounding brain tissue. The tumors were excised from medial portion because the feeding supply is usually derived from the medial and deep choroid plexus. As vital structures, including the optic radiation, thalamus, posterior horn of the internal capsule, and fornix, exist around the trigone, gentle dissection from the ventricle wall is needed. The hematoma was removed last to avoid obstructive hydrocephalus, and a drainage tube was left in the ventricle. Total gross resection of all the tumors was performed, and an approximate blood loss of 50-445ml(average 134.3ml)was recorded. None of the patients had permanent neurological deficit, and those with visual defects recovered postoperatively. Preservation of the visual and high brain function is an important consideration in the treatment strategy for tumors in the trigone of the lateral ventricle. The high parietal paramedian approach is a versatile and prominent approach that helps preserve these functions.

Long-term outcomes following thrombectomy for acute ischemic stroke in patients with a left ventricular assist device: a case series and literature review.

BACKGROUND: Left ventricular assist devices (LVADs) were developed for the treatment of patients with severe heart failure (HF) as a bridge to heart transplantation (HT). Although long-term LVAD support results in substantial improvements, their long-term use often leads to severe acute ischemic stroke (AIS). Serious neurological events make it difficult to continue LVAD support, and these patients are excluded as candidates for HT. AIS remains a challenging problem in patients receiving LVAD support. Recently, although thrombectomy has been established in selected patients who are independent, it has not been established in patients who are not completely independent, such as those with LVAD support. METHODS: We describe four AIS patients with severe HF who were implanted with an LVAD as a bridge to HT. Five mechanical thrombectomies were performed for AIS associated with an LVAD in four patients. A literature review is presented and compared to the present results. RESULTS: Good recanalization was achieved in all patients. In three cases, marked neurological improvement was observed, and modified Rankin Scale (mRS) scores were maintained without deterioration. The median total follow-up period was 592 days. In one patient, HT was successfully performed after thrombectomy. Currently, two of the patients without neurological deficits are awaiting HT. CONCLUSIONS: Embolism is a major problem encountered by patients under LVAD support while waiting for an HT. Thrombectomy for AIS associated with LVAD support is a useful and safe treatment modality. It is possible to maintain a reasonable mRS score in patients who are not completely independent.

Early surgical treatment benefits early staged pediatric moyamoya disease--single case report.

PURPOSE: Surgical revascularization for pediatric moyamoya disease improves cerebral blood flow (CBF) and consequently may prevent further ischemic events. However, the timing of the treatment is controversial especially for patients with no ischemic symptom and normal CBF. The purpose of this case report is to inform and infer the surgical treatment timing for pediatric moyamoya disease patients. CASE REPORT: A 10-year-old female patient with unilateral moyamoya disease complaining of only headache as a symptom and whose Suzuki stage was II or in transition to III by angiography and CBF was almost normal was admitted to Tokyo Women's Medical University Hospital. We performed superficial temporal artery-middle cerebral artery (STA-MCA) double anastomoses for the patient because we estimated her headache was derived from low perfusion in the brain. STA-MCA bypass surgery was not only effective for relief of her severe headache but also valid for her cerebral perfusion. Her angiography showed much supply from external carotid artery to intracranial arteries via bypass grafts in 7 months. CONCLUSION: Our case showed early surgical treatment was beneficial for relief of severe headache even for early staged pediatric moyamoya disease patients by improving perfusion pressure and cerebral circulation.

[A surgical fenestration of an arachnoid cyst in the cerebellomedullary cistern].

Arachnoid cysts originating from the cerebellomedullary cistern are very rare, and their indications for surgical treatment remain controversial. A 41-year-old man with a cystic lesion in the left cerebellomedullary cistern presented with sudden perspiration, palpitations, and vertigo. Subsequently, he complained of numbness of the left extremities and a dull headache. Otolaryngological evaluation revealed no abnormality. Physical examination on admission showed no neurological manifestations, except for left sensory disturbance. MRI revealed a cyst in the left cerebellomedullary cistern. Radiological examination did not reveal direct compression of the brain stem by the cyst, but the left cerebellum was compressed by the cyst. The patient underwent surgical fenestration of the arachnoid cyst via the midline suboccipital approach. The symptoms immediately disappeared after surgery. Patients with an arachnoid cyst in the cerebellomedullary cistern usually present lower cranial nerve dysfunction as a symptom. In our case, there was no cranial nerve dysfunction, but anatomically unexplainable symptoms, such as perspiration, palpitations, dizziness, and numbness of the left limbs, were observed. In conclusion, even if a patient with an arachnoid cyst in the posterior cranial fossa presents unexplainable symptoms, surgical intervention, including fenestration, is one of the therapeutic options.

Pathological characteristics of reoperated regrowing clinically nonfunctioning pituitary tumor cases in comparison with initial surgical cases.

Objective: Postoperative nonfunctioning pituitary tumor (NFPT) regrowth is a significant concern, but its predictive factors are not well established. This study aimed to elucidate the pathological characteristics of NFPTs indicated for reoperation for tumor regrowth. Methods: Pathological, radiological, and clinical data were collected from patients who underwent repeat operation for NFPT at Moriyama Memorial Hospital (MMH) between April 2018 and September 2023. For comparison, we also gathered data from patients who underwent initial surgery for NFPT during the same period at MMH. Results: Overall, 61 and 244 NFPT patients who respectively underwent reoperation and initial operation were evaluated. The mean period between the previous operation and reoperation was 113 months. Immunonegativity for any adenohypophyseal hormone was significantly more frequent in the reoperation group than in the initial operation group. In addition, the rate of hormone-negative but transcription factor-positive (H-/TF+) tumors among silent gonadotroph tumors was significantly higher in the reoperation group than in the initial operation group. Furthermore, seven silent corticotroph tumors (SCTs) in the reoperation group were ACTH-negative but TPIT-positive. Because most of the previous surgeries were performed in other hospitals a long time ago, we could procure the previous pathological results with immunohistochemistry (IHC) only from 21 patients. IHC for TF had not been performed in all the previous specimens. IHC for adenohypophyseal hormone was almost the same as the current results, and many H-/TF+ tumors were previously diagnosed as NCT. In addition, the reoperated patients were classified into 3 groups on the basis of the condition of the previous operation: gross total resection (GTR), 12 patients; subtotal resection (STR), 17 patients; and partial resection (PR), 32 patients. The mean Ki-67 LI in the GTR, STR, and PR subgroups were 1.82, 1.37, and 0.84, respectively, with the value being significantly higher in the GTR subgroup than in the PR subgroup (P < 0.05). Conclusions: The ratio of H-/TF+ tumors is significantly higher in symptomatically regrown tumors than in the initial cases, which used to be diagnosed as NCT. PR cases tend to grow symptomatically in a shorter period, even with lower Ki-67 LI than GTR cases.

[A brain metastasis from ampullary carcinoma: a case report].

We report a rare case of brain metastasis from ampullary carcinoma. A 61-year-old woman who had a past history of ampullary carcinoma surgically treated two year previously, presented with symptoms of left visual disturbance and left hemiparesis. Brain magnetic resonance images demonstrated a right occipital lobe tumor with peritumoral edema and midline shift. Gross total resection was carried out. Pathological diagnosis was poorly differentiated adenocarcinoma with compartments of signet-ring cell carcinoma. Metastases outside the abdominal cavity are rare. Brain metastases from ampullary carcinomas are extremely rare and there are few reports about such cases.

Aspergillus sphenoiditis growth on long cut ends of a non-absorbable sellar floor dura closure suture.

BACKGROUND: Cerebrospinal fluid (CSF) rhinorrhea is a common complication after transsphenoidal surgery (TSS). Suturing of sellar dura is effective in the prevention of postoperative CSF rhinorrhea, but it may cause rare postoperative infections. Herein, we report a case of Aspergillus sphenoiditis with the growth noted on cut ends of a polyvinylidene fluoride (PVDF) suture used for dural closure. CASE DESCRIPTION: A previously healthy 51-year-old woman complained of abnormal odor 5 years after TSS for null cell adenoma. A white mass in the sphenoidal sinus was detected on rhinoscopy. Fungal balls were found clustered around the ends of a PVDF suture used for dural closure at the initial surgery. She underwent removal of both the fungal ball and dural suture. The pathological diagnosis was Aspergillus hyphae. It is thought that a dural suture protruding out of the sphenoid sinus mucosa can cause Aspergillus infection even in immunocompetent patients. A rapid and accurate diagnosis followed by surgical removal of the fungal ball and follow-up with oral antimycotic drugs result in good clinical outcomes. CONCLUSION: It is crucial to cut short the suture end and cover it with sphenoid sinus mucosa to avoid such complications.

High-flow bypass using saphenous vein grafts with trapping of ruptured blood blister-like aneurysms of the internal carotid artery: patient series.

BACKGROUND: Trapping an aneurysm after the establishment of an extracranial to intracranial high-flow bypass is considered the optimal surgical strategy for ruptured blood blister-like aneurysms (BBAs) of the internal carotid artery (ICA). For high-flow bypass surgeries, a radial artery graft is generally preferred over a saphenous vein graft (SVG). However, SVGs can be advantageous in acute-phase surgeries because of their greater length, easy manipulability, ability to act as high-flow conduits, and reduced risk of vasospasms. In this study, the authors presented five cases of ruptured BBAs treated with high-flow bypass using an SVG followed by BBA trapping, and they reported on surgical outcomes and operative nuances that may help avoid potential pitfalls. OBSERVATIONS: After the surgeries, there were no ischemic or hemorrhagic complications, including symptomatic vasospasms. In three of the five cases, postoperative modified Rankin scale scores were between 0 and 2 at the 3-month follow-up. In one case, the SVG spontaneously occluded after surgery while the protective superficial temporal artery (STA) to middle cerebral artery (MCA) bypass became dominant, and the patient experienced no ischemic symptoms. LESSONS: High-flow bypass using an SVG with a protective STA-MCA bypass followed by BBA trapping is a safe and effective treatment strategy.

Intracranial Mycotic Aneurysm after Left Ventricular Assist Device Implantation Treated with Trans-arterial Embolization via the Brachial Artery: A Case Report.

Implantation of left ventricular assist device (LVAD) is widely performed in patients with end-stage chronic heart failure. Infection and stroke are major complications after LVAD implantation. However, the incidence of intracranial mycotic aneurysm after LVAD implantation is rare, and with no standard of care. In this study, we describe a case of an intracranial mycotic aneurysm after LVAD implantation that was successfully treated with trans-arterial embolization (TAE) with N-butyl 2-cyanoacrylate (NBCA) via the brachial artery. A 49-year-old man with a history of implantation of LVAD for ischemic cardiomyopathy was admitted to our institution. He had infectious endocarditis and was administered systemic antibiotics. At 3 weeks after admission, intracranial mycotic aneurysm of the left posterior parietal artery was detected during a diagnostic examination for asymptomatic intracranial hemorrhage. Anticoagulant therapy was administered to prevent thromboembolic complications of LVAD implantation. Under local anesthesia, TAE with NBCA was performed via the brachial artery because of the tortuous anatomy of the origin of the innominate artery and implant of the aortic arch. The aneurysm was completely obliterated. The patient was discharged without neurological deficits. TAE using NBCA could be an effective modality for the treatment of intracranial mycotic aneurysm after LVAD implantation.

Treatment Strategy for Recurrent Hemorrhage from Meningioma: Case Report and Literature Review.

BACKGROUND: We came across a rare case of recurrent hemorrhage from a meningioma. Here, we describe this case and discuss the treatment strategies for recurrent hemorrhage from a meningioma using a literature review. CASE DESCRIPTION: A 61-year-old woman with a history of 2 episodes of hemorrhage from a meningioma originating from the left falx cerebri presented to our outpatient clinic. She was asymptomatic, and magnetic resonance imaging revealed a small tumor along the falx cerebri. However, we decided to remove the hemorrhagic meningioma. No abnormal vascular structures were recognized on preoperative angiography and intraoperative evaluation. The tumor was easily removed along the falx cerebri (Simpson grade I). The pathologic diagnosis was transitional meningioma, World Health Organization grade I. The patient experienced no recurrence of tumor or hemorrhage for up to 15 months after surgery. CONCLUSIONS: The incidence of repeated bleeding from meningiomas is very rare and is seldom reported because the mortality associated with hemorrhage in meningiomas is high (28%-50%). Immediate diagnosis and surgical treatment with both hematoma evacuation and tumor removal are crucial to avoid inadequate and delayed treatment that may cause mortality.

Direct double bypass using the posterior auricular artery as initial surgery for moyamoya disease: technical note.

Surgical treatments for moyamoya disease (MMD) include direct revascularization procedures with proven efficacy, for example, superficial temporal artery (STA) to middle cerebral artery (MCA) bypass, STA to anterior cerebral artery bypass, occipital artery (OA) to MCA bypass, or OA to posterior cerebral artery bypass. In cases with poor development of the parietal branch of the STA, the posterior auricular artery (PAA) is often developed and can be used as the bypass donor artery. In this report, the authors describe double direct bypass performed using only the PAA as the donor in the initial surgery for MMD.In the authors' institution, MMD is routinely treated with an STA-MCA double bypass. Some patients, however, have poor STA development, and in these cases the PAA is used as the donor artery. The authors report the use of the PAA in the treatment of 4 MMD patients at their institution from 2013 to 2016. In all 4 cases, a double direct bypass was performed, with transposition of the PAA as the donor artery. Good patency was confirmed in all cases via intraoperative indocyanine green angiography and postoperative MRA or cerebral angiography. The mean blood flow measurement during surgery was 58 ml/min. No patients suffered a stroke after revascularization surgery.

Predicting the Occurrence of Hemorrhagic Cerebral Hyperperfusion Syndrome Using Regional Cerebral Blood Flow After Direct Bypass Surgery in Patients with Moyamoya Disease.

OBJECTIVE: Superficial temporal artery-middle cerebral artery anastomosis is an established treatment for moyamoya disease. However, hemorrhagic cerebral hyperperfusion syndrome (CHS) leads to poor outcomes. This study aimed to identify predictors of hemorrhagic CHS based on regional cerebral blood flow (rCBF) in patients with moyamoya disease. METHODS: The study included 251 hemispheres in 155 patients with moyamoya disease who underwent preoperative and postoperative rCBF measurements and superficial temporal artery-middle cerebral artery double anastomosis. We used rCBF increase rate for predicting hemorrhagic CHS. rCBF increase rate was calculated by 2 methods. In method 1, the rCBF value on the operated side was compared with the rCBF value on the nonoperated side. In method 2, the postoperative rCBF value on the operated side was compared with the preoperative rCBF value on the operated side. Patients were classified into 4 groups according to rCBF increase rate to predict risk of hemorrhagic CHS. RESULTS: Hemorrhagic CHS occurred in 7 (2.8%) hemispheres (no children). Severe hemorrhagic CHS occurred in only 1 (0.4%) hemisphere. Hemorrhagic CHS was observed in patients with ≥30% rCBF increase according to method 1 and ≥50% rCBF increase according to method 2 and was most frequently noted in ≥100% rCBF increase. CONCLUSIONS: Predictors for hemorrhagic CHS were ≥30% rCBF increase when using method 1 and ≥50% increase when using method 2.

Decompression by Cutting the Tentorium for Trigeminal Neuralgia Caused by Vertebrobasilar Dolichoectasia.

BACKGROUND: Trigeminal neuralgia caused by vertebrobasilar dolichoectasia (VBD) is rare and challenging to treat. Some authors have reported techniques for treating trigeminal neuralgia caused by VBD using various kinds of objects including clips, Proline slings, and titanium plates. METHODS: Here, we report the effectiveness of cutting and splitting of the tentorium in 3 patients with trigeminal neuralgia. RESULTS: The clinical results were good, the pain disappeared in all patients without medication, and no complications occurred. CONCLUSIONS: In cases of trigeminal neuralgia caused by VBD, this technique may be as useful as traditional microvascular decompression around the trigeminal nerve root entry zone.

Ultrarapid Evaluation of Meningioma Malignancy by Intraoperative Flow Cytometry.

BACKGROUND: The prognosis for World Health Organization (WHO) grade II/III meningiomas is worse than for WHO grade I meningiomas. Histopathologic grade should ideally be identified during tumor resection, but current methods are time-consuming and have doubtful reliance. The aim of this study was to evaluate intraoperative flow cytometry (iFC) as a method for providing ultrarapid evaluation of meningioma malignancy. METHODS: A total of 117 meningiomas were analyzed with iFC during surgery. For each, the malignancy index (MI) was calculated as the number of cells with a greater than normal DNA content as a proportion of the total number of cells. Each specimen was investigated histopathologically and was diagnostically graded according to the 2016 WHO grading system. MI results were compared with WHO grades of the meningiomas. RESULTS: The automatic measurement of iFC took approximately 9 minutes on average. The difference in MI between grade I and grade II/III meningiomas was statistically significant (P < 0.001). Receiver operating characteristic analysis provided an optimal cutoff MI value of 8.0% for discrimination between grade I and grade II/III groups, with 64.7% sensitivity and 85.0% specificity for grade II/III meningiomas. CONCLUSIONS: Our method of calculating MI with iFC appears to be technically feasible and reliable for ultrarapid evaluation of meningioma malignancy. MI with iFC could potentially enable determination of an optimal treatment strategy during surgery, such as extent of resection of the tumor and management of invaded normal brain or nerves.

Stent-assisted coil embolisation for bilateral vertebral artery dissecting aneurysms presenting with subarachnoid haemorrhage.

Bilateral dissecting aneurysms presenting with subarachnoid haemorrhage are rare. The treatment strategy for bilateral vertebral artery dissecting aneurysms is controversial because the contralateral vertebral artery is already dissected and can easily undergo enlargement or bleed after non-reconstructive treatment procedures such as trapping or proximal occlusion. Here, we report a case of bilateral vertebral artery dissecting aneurysm presenting with subarachnoid haemorrhage that was treated with stent-assisted coiling for the ruptured side. A 42-year-old man was admitted to our hospital with sudden headache (WFNS grade 1). Computed tomography showed a high-density region in the basal cistern and posterior fossa with more haemorrhage on the right side (Fisher group 3). Three-dimensional computed tomography and three-dimensional rotational angiography demonstrated a bilateral round protrusion on the vertebral arteries with a diameter of 5 mm just distal to the posterior inferior cerebellar artery. Stent-assisted coiling was performed for the ruptured right side and conservative therapy was selected for the contralateral side. The ruptured side was well embolised, and the contralateral side was stable over the 12-month follow-up period after treatment. The treatment strategy for bilateral vertebral artery dissecting aneurysms presenting with subarachnoid haemorrhage is different from that for unilateral vertebral artery dissecting aneurysms. Non-reconstructive treatment procedures such as trapping may cause contralateral enlargement or rupture; therefore, reconstructive treatment may be appropriate for the ruptured side.

Delayed cerebral ischemia associated with reversible cerebral vasoconstriction in a patient with Moyamoya disease with intraventricular hemorrhage: Case report.

We describe a case of cerebral infarctions caused by transient vasoconstrictions in the posterior circulation 2 weeks after intraventricular hemorrhage without subarachnoid hemorrhage in a 35-year-old patient with Moyamoya disease. To our knowledge, this is the first case report where diffuse segmental vasoconstrictions of the basilar and posterior cerebral arteries were recognized after intraventricular hemorrhage in Moyamoya disease. The patient complained of severe and acute-onset headache 14 days after the intraventricular hemorrhage, which had a different character and severity from the one she complained of at the onset of intraventricular hemorrhage. Finally, headache disappeared within 1 month and vasoconstriction resolved in 2 months. Reversible cerebral vasoconstriction syndrome was under consideration for the etiology of her condition because of the "thunderclap" characteristics of the headache and the delayed timing of occurrence of the vasoconstriction. This case report informs and alerts neurologists, neurosurgeons and neuroradiologists who observe and treat patients with Moyamoya disease that vasoconstriction in the posterior circulation may occur after intraventricular hemorrhage in these patients.