Treatment strategy for giant thrombosed aneurysm of the basilar artery with associated obstructive hydrocephalus.

Background: There is no established adequate treatment for thrombosed aneurysm of the basilar artery with obstructive hydrocephalus. We conducted coil embolization and peritoneal shunting followed by placement of a stent expected to exert flow diversion (FD) effects to treat 2 patients with giant thrombosed aneurysms of the basilar artery with associated obstructive hydrocephalus, with good results. Methods: From April 2019 to March 2021, consecutive two cases of symptomatic hydrocephalus due to giant thrombosed aneurysms in the posterior cranial fossa at our hospital were treated. At first, coil embolization was performed to prevent aneurysm rupture. After coil embolization, ventriculoperitoneal shunting was performed. Finally, stent-assisted coil embolization was performed with flow re-direction endoluminal device (FRED) or low-profile visualized intraluminal support device (LVIS) stent. Results: Both patients were discharged after recovering well, with no postoperative hemorrhagic or ischemic complications. Conclusion: Staged surgery using a FRED for flow diverter or an LVIS stent expected to have FD effects may offer an effective treatment option.

Usefulness of the Three-step Simple Binostril Approach in Endoscopic Endonasal Transsphenoidal Surgery.

We describe a three-step, simple binostril approach to endoscopic endonasal transsphenoidal surgery in cases of sellar/parasellar lesions. In the first step, the mucosa of the lower third of the ethmoid bulla on the outside was coagulated with monopolar microdissection needle and opened to create space on the outside of the middle turbinate. The middle turbinate was moved outward using this space, and the natural ostium of the sphenoid sinus could be confirmed easily. In the second step, a less than 10 mm incision was made from the right natural ostium of the sphenoid sinus to the right nasal septal mucosa. The anterior wall of the sphenoid sinus was removed to free the sphenoid sinus. In the third step, the instrument was inserted through the left nostril using a hole connected to the natural ostium of the sphenoid sinus to reach the sellar floor via both nostrils. It took longer for the trainee than for the instructor to reach the sellar floor in the first four cases. However, there was no significant difference in the approach time after the fifth case. Approach-related postoperative complications were observed in 52 cases of sellar/parasellar lesions performed. This approach was considered to provide sufficient space and was simple and less burdensome to the patient.

Usefulness and problems of Y-Stent and T-Stent assisted coiling for unruptured cerebral aneurysms.

INTRODUCTION: We are going to discuss about usefulness and problems of Y-stent and T-stent assisted coiling for unruptured cerebral aneurysms. METHODS: A retrospective review was performed to identify patients who were treated using Y-stent or T-stent assisted coiling (Y-SAC, T-SAC) for 25 unruptured cerebral aneurysms from April 2017 to September 2021. Fifteen cases were treated using Y-SAC, 10 were done using T-SAC. Only a case was treated with Low-profile Visualized Intraluminal Support (LVIS; MicroVention TRUMO, Aliso Viejo, California, USA) and Neuroform ATLAS (Striker, Kalamazoo, Michigan, USA), Others were done with two Neuroform ATLAS stents. RESULTS: Y-SAC and T-SAC were succeeded in all cases. In two cases that were treated using Y-SAC, ischemic complications were observed. A patient received additional embolization because subarachnoid hemorrhage (SAH) was appeared after discharge. On follow-up imaging, complete occlusion (CO) was confirmed in all cases. CONCLUSION: The position of deployment of stents was the most important issue. In particular, the second stent should be deployed as to contact the first stent, as possible. The case that the position of the second stent was shifted, and neck was not covered was observed. In the cases that are treated by using T-SAC, microcatheter must be navigated to distal position as possible. In that point, Y-SAC is more applicable. The familiarization of Y-SAC or T-SAC will expand the indication of endovascular treatment for unruptured cerebral aneurysms.

Successful use of an LVIS device to treat unruptured distal aneurysm of the superior cerebellar artery at a vascular bifurcation.

Background: Aneurysms of the distal superior cerebellar artery (SCA) account for only a small proportion of all cerebral aneurysms. Reports of the use of flow diverters (FDs) started to appear in 2013. We obtained good results from placement of a low-profile visualized intraluminal support device (LVIS) to treat unruptured distal aneurysm of the SCA at a vascular bifurcation. Case Description: A 65-year-old man presented at our hospital with sudden peripheral facial nerve palsy and suspected subarachnoid hemorrhage. Investigational cerebral angiography revealed an aneurysm at the bifurcation of the caudal and rostral trunks of the SCA. An LVIS was placed with the aim of obtaining flow diversion, and cerebral angiography 6 months after this procedure showed disappearance of aneurysm with preservation of the distal SCA. Conclusion: Twelve cases of the use of FDs to treat aneurysms of the SCA have been reported previously. However, none of those reports described FD use to treat an aneurysm at a vascular bifurcation, as in the present case. Our results suggested that LVIS placement with the aim of obtaining flow diversion may be useful for the treatment of aneurysms at such sites.

Usefulness of endoscope-assisted surgery under exoscopic view in skull base surgery: A technical note.

BACKGROUND: The use of the exoscope has been increasing in the field of neurosurgery, as it can set the visual axis freely, enabling the surgeon to operate in a comfortable posture. Although endoscope-assisted surgery for compensation of insufficient surgical field is useful under the microscope, we report that using an endoscope in exoscopic surgery is safer and more useful. METHODS: The exoscope used was ORBEYE. All surgical procedures were performed exoscopically from the beginning of the surgery. When endoscopic observation was required during the operation, the endoscope was inserted under observation by an exoscope. The exoscopic screen was 4K-3D and endoscopic screen was 4K-2D, the operation was performed while observing both screens at the same time. The endoscope was held manually or by a mechanical holder. RESULTS: Twenty-two cases, including 14 requiring microvascular decompression (MVD) and eight requiring tumor removal, were performed by endoscopic-assisted exoscopic surgery. The endoscope could be inserted safely because its relationship with the surrounding structure could be observed under the exoscope, and the operator could observe both screens without moving the head. Fourteen of 22 patients required additional endoscopic treatment. Satisfactory two-handed operation was performed in 13 cases. Symptomatology disappeared in all cases of MVD, and sufficient tumor resection was achieved. CONCLUSION: Exoscopic surgery provides excellent surgical view that is not inferior to conventional microsurgery. As a large space can be secured between the scope and the surgical field, it is safer and easier to manipulate the endoscope under the exoscope.