Treatment Result in the Initial Stage of Kanazawa Mobile Embolectomy Team for Acute Ischemic Stroke.

Five recent multicenter randomized controlled trials (RCTs) have clearly shown the superiority of mechanical thrombectomy in large vessel occlusion acute ischemic stroke compared to systemic thrombolysis. Although 14 hospitals in Ishikawa prefecture have uninterrupted availability of systemic thrombolysis, mechanical thrombectomy is not available at all of these hospitals. Therefore, we established a Kanazawa mobile embolectomy team (KMET), which could travel to these hospitals and perform the acute reperfusion therapy. In this article, we report early treatment outcomes and validate the effectiveness of a network between affiliated hospitals and KMET. Between January 2014 and December 2015, 48 patients, aged 45-92 years (mean: 73.0 years), underwent acute reperfusion therapy provided by KMET in 10 affiliated hospitals of Kanazawa University Hospital. The pre-treatment NIHSS scores ranged from 5 to 39 (mean: 19.1). ASPECTS+W ranged from 1 to 11 (mean: 7.3). Successful revascularization, defined as thrombolysis in cerebral infarction (TICI) 2b or 3, was achieved in 38/48 cases (80%), and a good outcome, defined as modified Rankin Scale (mRS) score from 0 to 2 at 90 days after the treatment, was achieved in 24/48 cases (50%). There were two cases of intracranial bleeding (4%). Mean time from onset to recanalization was 297 min. These results, which are similar to those of five previous RCTs, suggest that a collaborative network between affiliated hospitals and KMET is effective for acute reperfusion therapy in local areas wherein experienced neuroendovascular specialists are insufficient.

Midline dural filum of the sellar floor: Its relationship to the septum attachment to the sellar floor and the ossification in the sphenoid sinus.

OBJECTIVES: It is important to identify and maintain a midline orientation during endoscopic transsphenoidal surgery (ETSS) for sellar lesions to prevent critical injury to the internal carotid artery. Therefore, the preoperative neuroradiological assessment of the bony structures in the sphenoid sinus, including the septum attachment to the sellar floor and its surrounding structures, is essential. It has been reported that the midline filum of the sellar dura can function as a useful intraoperative orientation guide during ETSS. However, the relationship between the midline dural filum and the intrasinus bony structures, such as the sellar floor, the intrasinus septation and the ossification, remains unclear and the mechanisms underlying development of the midline dural filum have also not yet been explored. METHODS: This retrospective study included 160 patients undergoing ETSS to assess both the midline dural filum and the intrasinus bony structures, using video recording reviews. The intrasinus septum and the ossification in the sphenoid sinus were evaluated on the computed tomography images of the bone window. RESULTS: A midline dural filum was identified in 66 (41.3%) of 160 patients. Attachment of the septum to the sellar midline was found in 61 (39.4%) of 155 patients, after excluding 5 patients with the conchal type of sphenoid sinus, 55 (90.2%) of 61 patients with a septum on the midline and only 6 (6.4%) of the remaining 94 patients without a septum on the midline had a midline dural filum. The relationship between a midline dural filum and a septum on midline was statistically significant (p<0.001), regardless of the number of intrasphenoidal septa. In terms of the types of sphenoid sinus, the midline dural filum was predominantly detected in patients where ossification extended over the midline filum. In patients with the sellar type of sphenoid sinus, 49 (36.0%) of 136 had a midline dural filum, meanwhile, 16 (84.2%) of 19 patients with the pre-sellar type (p=0.039) and all 5 patients (100%) with the choncal type harbored a midline dural filum (p<0.001). CONCLUSION: This study clearly verified the importance of the midline dural filum in a large series and evaluated the obvious relationship between the midline dural filum and the bony structures on the sellar floor. Our results strongly suggest that, during developing of the midline dural filum, the sellar dura becomes tethered to the bony elements attached to the sellar surface, such as the septum on the midline and the ossification in both the pre-sellar and the conchal type of sphenoid sinus.

Significant improvement of intractable headache after transsphenoidal surgery in patients with pituitary adenomas; preoperative neuroradiological evaluation and intraoperative intrasellar pressure measurement.

OBJECT: Headache is the most common symptom of both primary and metastatic brain tumor, and is generally considered the primary symptom in patients with large pituitary adenomas. However, patients with small pituitary adenomas rarely complain of intractable headache, and neurosurgeons are unsure whether such small adenomas actually contribute to headache. If conventional medical treatments for headache prove ineffective, surgical removal of the adenoma can be considered as an alternative management strategy. METHODS: We conducted a retrospective review of 180 patients who underwent transsphenoidal surgery (TSS) for pituitary adenomas at Kanazawa University Hospital between 2006 and 2014. Patients with acute phase intratumoral hemorrhage were excluded. We identified nine patients with intractable headache as the chief complaint associated with small pituitary adenoma (diameters 15.8 ± 2.6 mm, 11-20 mm), non-functioning in eight, and prolactin-secreting in one. The preoperative neuroradiological studies and headache characteristics were assessed retrospectively, and the intrasellar pressure evaluation was performed during TSS in the last seven patients. RESULTS: All nine patients had complete or substantial resolution of their formerly intractable headache after TSS. Headaches consisted of ocular pain ipsilateral to the adenoma localization within the sella in four cases and bifrontal headache in five. Magnetic resonance imaging of these patients revealed small diaphragmatic foramen, which were so narrow that only the pituitary stalk could pass. Computed tomography scans showed ossification beneath the sellar floor in the sphenoid sinus, presellar type in six cases, and choncal type in three. The adenomas included cysts in seven cases. There was no cavernous sinus invasion. Intrasellar pressure measurements averaged 41.5 ± 8.5 mmHg, range 34-59, significantly higher than in control patients without headache (n = 12), namely 22.2 ± 10.6 mmHg (16-30). CONCLUSION: In this study, the authors demonstrated the validity of TSS in the treatment of intractable headache associated with pituitary adenoma. The presence of ocular pain, especially ipsilateral to the adenoma, integrity of the diaphragm sella, and ossification in the sphenoid sinus, cyst or hemorrhage and the absence of cavernous sinus invasion were the indications for TSS for patients complaining of intractable headache and having pituitary adenomas.

Massive Hemorrhage from the Posterior Ethmoidal Artery during Transsphenoidal Surgery: Report of 2 Cases.

Nasal bleeding is a major complication that can occur during and after transsphenoidal surgery (TSS) for intra- and suprasellar tumors. In most cases, the cause of this bleeding can be attributed to a branch of the maxillary artery called the sphenopalatine artery, injury to which can lead to life-threatening situations. Upon exposure of the suprasellar region and planum sphenoidale during surgery, it is also important to avoid damaging the posterior ethmoidal artery (PEA), a branch of the ophthalmic artery. While recent advancement in endoscopic techniques enables the performance of extended TSS, the chances of PEA injury seem to be increasing. In the current report, we present two cases that showed massive PEA bleeding during regular (not extended) TSS. The total blood loss was 2280 ml and 2150 ml, and endoscopic views disturbed by the massive hemorrhages remarkably delayed accurate stanching of the responsive artery. Therefore, anatomical recognition of the PEA is required to avoid fatal hemorrhaging during even regular TSS, especially for the beginners of this surgery.

Adenoid cystic carcinoma in the cavernous sinus diagnosed with the endoscopic endonasal approach.

A 42-year-old woman presented with right oculomotor, abducens, and trigeminal palsy. Neuroimaging revealed a small lesion in the right cavernous sinus mimicking meningioma. Because the symptoms gradually worsened, the patient underwent an endoscopic endonasal transsphenoidal surgery for tumor biopsy. Histological examination of the surgical specimen revealed adenoid cystic carcinoma (ACC). Before and after the operation, no evidence of other primary lesions could be detected. The patient was treated with stereotactic radiosurgery (SRS). ACC in the cavernous sinus can be difficult to diagnosis before histological confirmation, because it is extremely rare as a primary lesion and resembles a cavernous sinus meningioma on neuroimaging studies. Two years after the first SRS, the tumor recurred along the trigeminal nerve and SRS was performed again. Our study illustrates that in case in which a lesion in the cavernous sinus progresses on neurological and neuroimaging studies, a biopsy should be taken to provide most accurate diagnosis and treatment.

A reevaluation of the primary diagnosis of hemangiopericytoma and the clinical importance of differential diagnosis from solitary fibrous tumor of the central nervous system.

OBJECTIVES: Hemangiopericytomas (HPCs) are rare neoplasms with relatively high rates of recurrence and extracranial metastasis. Though the differential diagnoses from angiomatous meningiomas and from solitary fibrous tumors (SFTs) are both important, the latter diagnosis is somewhat more important in light of the benign prognosis of SFTs and the difficulties in distinguishing SFTs from HPCs. Newly developed immunohistochemical methods reveal differences in the specific immunohistochemical features of HPCs and SFTs. To elucidate whether SFTs have been misdiagnosed as HPCs in the past, our group used recent immunohistochemical methods to re-evaluate tissues that had been originally diagnosed as HPCs. We also compared the clinical features of these cases. PATIENTS AND METHODS: Thirteen sequential cases of HPC diagnosed in Kanazawa University Hospital and Kumamoto University Hospital between 1970 and 2006 were retrospectively analyzed by immunohistochemical staining for CD34, Bcl-2, epithelial membrane antigen (EMA), vimentin, and S100 protein, and by measurement of the MIB-1 labeling index (LI). The cases were then re-evaluated and newly diagnosed based on the results of the immunohistochemical stainings. The clinical course of each case was also evaluated. RESULTS: Four of the 13 cases were newly diagnosed as SFTs and eight were reconfirmed as HPCs, based on the immunohistochemical studies for CD34, Bcl-2, and reticulin staining. One case was newly diagnosed as meningioma on the basis of a strong EMA positivity. The MIB-1 LI was less than 1% in 12 of the cases. In two cases, one case of HPC and the other of meningioma, the MIB-1 LI was relatively high, 8% and 4% respectively. All eight of the HPCs recurred, and 5 of the HPC patients died of the disease. Only one case of the SFTs recurred. CONCLUSION: Our study suggests that a relatively high percentage of the tumors diagnosed as HPCs in the past may have in fact been intracranial SFTs. Immunohistochemical examinations of CD34, Bcl-2, and reticulin stains are keys for the differential diagnosis. Given that SFTs have a considerably better prognosis than HPCs, it is important to carry out meticulous immunohistochemical examinations for the primary diagnosis.

Simulation of clipping position for cerebral aneurysms using three-dimensional computed tomography angiography.

A novel method for the simulation of the clipping position for cerebral aneurysms based on three-dimensional computed tomography (3D CT) angiography was evaluated. Rotating the regional 3D CT angiography images including the aneurysm provided the virtual intraoperative views of 36 cerebral aneurysms that were eligible for clipping through a pterional approach with a perpendicularly applied straight clip. The cut-along-trace function of the 3D CT workstation was used to simulate the clipping position. The presence or absence of aneurysm remnants was preoperatively evaluated by observing the clipping simulation image. Intraoperative endoscopy and postoperative cerebral angiography were routinely performed to confirm the completeness of obliterations. Nineteen of 21 aneurysms for which complete obliteration was preoperatively expected were confirmed to have no aneurysm remnant. Nine of 15 aneurysms which were expected to have aneurysm remnant were confirmed to persist. The clipping simulation images could correctly predict aneurysm remnant after the initial clipping with a sensitivity of 90.5% and specificity of 60%. The present simulation method can predict aneurysm remnants and improve the likelihood of complete obliteration by clipping.