Endoscopic clipping of intraventricular aneurysms using the "wet-field" technique.

Intraventricular hemorrhage and intracerebral aneurysms are relatively frequent complications associated with moyamoya disease. Prevention of aneurysm rerupture is important because it significantly decreases the morbidity and mortality rates. Aneurysms arising distal to collateral flow are sometimes observed in patients with intraventricular hemorrhage; however, the treatment of these aneurysms remains challenging because of their deep-seated location in the brain and accompanying narrow surgical corridor. The authors describe a neuroendoscopic aneurysm clipping technique performed in 2 cases using a small-diameter tubular retractor for intraventricular aneurysms of the distal lateral posterior choroidal artery. In this technique, the surgical field was continuously irrigated with artificial CSF to keep the ventricle size intact, and aneurysm clipping was performed through a tubular retractor that was introduced with neuronavigational guidance. The patients' postoperative courses were uneventful, and CT angiography revealed complete clipping of the aneurysms and patent parent arteries. Endoscopic clipping using a tubular retractor is an effective and less invasive alternative for treating intraventricular aneurysms. The wet-field endoscopic technique is performed in an aqueous field and maintains an intact ventricle size, allowing for a clear surgical view and a wider, enhanced surgical field.

Fully endoscopic combined transsphenoidal and supraorbital keyhole approach for parasellar lesions.

OBJECTIVE Parasellar tumors that extend far laterally beyond the internal carotid artery or that are fibrous and adhere firmly to critical structures are difficult to remove totally via the endoscopic transsphenoidal approach alone. In such cases, a combined transsphenoidal-transcranial approach is effective to achieve maximal resection in a single stage. In this paper, a new minimally invasive surgical technique for complicated parasellar lesions, a fully endoscopic combined transsphenoidal-supraorbital keyhole approach, is presented. METHODS A retrospective review of patients who had been treated via a fully endoscopic combined transsphenoidal-supraorbital keyhole approach for complicated parasellar lesions was performed. The data for resection rate, perioperative mortality and morbidity, and postoperative outcomes were analyzed. RESULTS A total of 12 fully endoscopic combined transsphenoidal-supraorbital keyhole approaches were performed from March 2013 to February 2016; 10 were for pituitary adenomas and 2 were for craniopharyngiomas. Gross-total resection or near-total resection was achieved in 7 of 12 cases. Among the 11 patients who had presented with preoperative visual disturbances, 7 had visual improvement. However, 1 patient showed deterioration in visual function. No patient experienced postoperative hemorrhage, needed additional surgical treatment, or had postoperative CSF leakage. CONCLUSIONS In the combined transsphenoidal and transcranial approach, safe and effective cooperative manipulation with 2 surgical corridors can be performed for complicated parasellar lesions. The goal of this procedure is not to achieve gross-total resection, but to achieve safe resection. Moreover, this new surgical approach offers neurosurgeons a simpler operative field with less invasiveness than the conventional microscopic combined approach. The fully endoscopic combined endonasal-supraorbital keyhole approach is an efficacious procedure for complicated parasellar lesions with acceptable results.

The Multiscope Technique for Microvascular Decompression.

BACKGROUND: Endoscopic surgery has rapidly become widespread in neurosurgery in recent years. Endoscopy can offer close and panoramic surgical views with fine illumination, even in the deep intracranial area. However, it also has the following serious drawback: an intracranial blind area between the field lens of the endoscope and the site of the dural opening. This blind area cannot be viewed on the endoscopic monitor, and several surgical complications, including accidental intracranial neurovascular structural injury, can occur in this area. In this article, we report a new multiscope surgical technique that can compensate for this serious disadvantage of endoscopic surgery. METHODS: In the multiscope technique, endoscopic and exoscopic systems are used simultaneously with 2 monitors. Microvascular decompression (MVD) is performed fully endoscopically using an exoscope that compensates for the intracranial blind area of the endoscopic view. Two high-definition monitors for the endoscope and exoscope are placed side-by-side in front of the primary surgeon. RESULTS: Two patients with hemifacial spasm were treated by endoscopic MVD with the multiscope technique. In these procedures, fine surgical views were obtained by both the endoscope and exoscope. Two monitors were placed side-by-side in front of the surgeon; as a result, the physician could easily view them simultaneously during the operation. No surgery-related complications occurred. CONCLUSIONS: The multiscope technique can facilitate the performance of safer neuroendoscopic surgery than conventional endoscopic surgery. This technique can also be adopted in other skull base surgeries, in which the importance of endoscopy is growing.

Incidence and risk factors of subdural hematoma after intraoperative cerebrospinal fluid leakage during the transsphenoidal approach.

PURPOSE: The transsphenoidal approach (TSA) is regarded as the first line of treatment for sellar and suprasellar lesions. There are only few case reports of postoperative subdural hematoma after TSA and extended transsphenoidal approach (eTSA), and the detailed incidence and risk factors for this complication are still unknown. We reviewed the incidence and risk factors for subdural hematoma after TSA and eTSA. METHODS: Between January 1, 2013 and December 31, 2014, 165 consecutive patients underwent TSA or eTSA at Nagoya University Hospital and Nagoya Daini Red Cross Hospital. Fifty-one patients experienced intraoperative CSF leakage. Postoperative subdural hematoma was observed in 10 patients, all of whom experienced intraoperative CSF leakage. We reviewed clinical data including CT and MR images and examined factors related to subdural hematoma among patients with intraoperative CSF leakage. RESULTS: In univariate statistical analyses, risk factors for postoperative subdural hematoma were advanced age, high Evans' index, and preoperative hypopituitarism. These factors were also significant in the multivariate logistic regression analysis. There were no statistical differences in sex, tumor size, approach methods, preoperative diabetes insipidus, or degree of intraoperative CSF leakage. CONCLUSIONS: The incidence of postoperative subdural hematoma after intraoperative CSF leakage during TSA and eTSA was higher than the incidence reported in patients after craniotomy. Intraoperative CSF leakage should be avoided as much as possible, especially in patients with brain atrophy and/or enlargement of the ventricular system, even if the intent of the reconstruction technique is authenticity. In addition, patients with hypopituitarism should be carefully followed up after surgery.

Lateral temporal encephaloceles: case-based review.

PURPOSE: Lateral temporal encephalocele is an extremely rare clinical condition, with only 18 cases presented in the literature to date. No review articles have examined lateral temporal encephalocele in depth. We therefore reviewed past cases of lateral encephalocele to clarify the clinical characteristics of this extremely rare deformity. We also present a case of lateral encephalocele with arachnoid cyst which has never been reported in past reports. METHODS: We identified 8 reports describing 18 cases of lateral temporal encephalocele. We therefore reviewed 19 cases of lateral temporal encephalocele, including our own experience, and discussed the clinical characteristics of this pathology. RESULTS: All the cases with lateral temporal encephalocele were detected at birth except for an occult case. The majority occurred at the pterion, and occurrence at the asterion appears much rarer. Due to the preference for the pterion, the ipsilateral orbital wall was also distorted in some cases. Lateral temporal encephalocele seems to have fewer associated malformations: only 3 cases of lateral temporal encephalocele had associated malformations, including our case which was associated with intracranial arachnoid cyst. The only case of lateral temporal encephalocele to have shown hydrocephalus was our own case. Patients with this deformity have relatively good prognoses: only 3 of the 19 cases showed delayed psychomotor development during follow-up. CONCLUSIONS: Provision of adequate treatment is likely to achieve a good prognosis in patients with lateral temporal encephalocele, so we should keep in mind this deformity when encountering pediatric patients with mass lesions on the temporal cranium.