Faculty Bibliography

Intracranial tumors may rapidly enlarge during pregnancy. When the tumor abuts the optic apparatus, tumor growth may cause visual deterioration. The decisions regarding the management of these tumors should take into consideration visual function, fetal and maternal safety, and the ability for total resection of the tumor. The objective of the study was to describe our experience and to establish principles for management of intracranial tumors compressing the optic apparatus that present during pregnancy or in the early post partum period. A retrospective case-series review was conducted. Women who presented with visual deterioration either during pregnancy or in the early post partum period due to an intracranial tumor were included. Neurosurgical and obstetrical data were collected from the patients' hospital files and outpatient clinic records. Between 2005 and 2011, nine pregnant women with visual deterioration were diagnosed and treated. Of them, four underwent a neurosurgical procedure during pregnancy. Of the five patients who underwent surgery for tumor resection after delivery, three required urgent cesarean section either due to acute visual deterioration or obstetrical reasons. There was no maternal or fetal mortality and a good overall neonatal outcome was achieved. Improvement in visual acuity and visual fields was achieved in all patients. Postoperative complications included two cases of CSF leak, which resolved after treatment. Visual deterioration during pregnancy due to tumors that compress the optic apparatus requires treatment by a multi-disciplinary team. Surgery is well tolerated by mother and fetus during early and midpregnancy; thus, in cases where visual deterioration is detected, delay of surgery is not justified.

The differential diagnosis of a brain lesion with two discordant pathology reports includes the presence of collision tumor, metaplastic changes, and labeling errors that occurred during the processing of the specimen. The authors present a case in which the first brain biopsy from a 47-year-old patient with a history of heavy smoking was compatible with metastatic small cell carcinoma, and the second biopsy taken during decompression craniotomy 3 weeks later was compatible with WHO Grade IV glioblastoma. Using short tandem repeat (STR) analysis of the two specimens and nontumor-derived patient DNA, the authors found that the two specimens did not belong to the same individual. The authors conclude that allele imbalance or loss of heterozygosity detected by STR analysis is a reliable and valuable diagnostic tool for clarifying discrepancies in discordant pathology reports.

BACKGROUND: The use of minimally porous endoluminal devices (MPEDs) such as the Pipeline Embolization Device (PED) has been described for the treatment of brain aneurysms. The benefit of using MPEDs to assist embolization of a direct high-flow carotid cavernous fistula resulting from a ruptured cavernous carotid artery aneurysm is not well documented. METHODS: We describe our experience with deploying a tailored multidevice PED construct across the cavernous internal carotid artery (ICA) wall defect in combination with transarterial coil embolization using the "jailed microcatheter" technique. RESULTS: A 59-year-old woman presented with acute left-sided ophthalmoplegia. Diagnostic cerebral angiography demonstrated a ruptured giant cavernous carotid aneurysm with fistulous outflow via the ipsilateral left superior ophthalmic vein and into the pterygoid venous plexi bilaterally. Via the Marksman microcatheter, a total of three PEDs measuring 4.5 mm x 18 mm, 4.5 mm x 20 mm, and 4.75 mm x 16 mm were telescoped within the ICA across the aneurysm neck. Coiling of the aneurysm fundus and cavernous sinus via the "jailed" Rapidtransit microcatheter was subsequently achieved. A 2-year follow-up digital subtraction angiography (DSA) demonstrated stable obliteration of the aneurysm and the fistula, coincident with complete resolution of the patient's symptoms. CONCLUSIONS: Based on our long-term clinical and angiographic results, we advocate that the presented method be a valid treatment option for selected cases.

OBJECT The use of the Pipeline Embolization Device (PED) as a sole endovascular modality has been described for the treatment of brain aneurysms. The benefit of using coils concurrently with a limited number of PEDs is not well documented. The authors describe their experience with this technique as well as their midterm clinical and angiographic results. METHODS This is a retrospective review of patients treated between 2011 and 2014. The authors placed a minimal number of PEDs with the addition of coils using a "jailed" microcatheter technique. A partially dense coil mass was obtained. Immediate and midterm clinical and angiographic results are reviewed. RESULTS The authors treated 27 patients harboring 28 aneurysms using this technique. The mean aneurysm size was 11.9 mm, and the mean neck size was 5.4 mm. A mean of 1.48 PEDs were placed per patient, and a mean of 1.33 PEDs per aneurysm were placed. The Raymond score immediately after PED placement was 2 or 3 in 82.1% of the patients. There were no intraprocedural or postprocedural complications. All PEDs were successfully deployed. No clinical or technical adverse effects related to the coil mass were observed. There were no clinical or radiographic signs of ischemia in this group. At follow-up imaging, complete aneurysm occlusion was demonstrated on the first MR angiogram (3-5 months) in all patients who reached this milestone. Follow-up digital subtraction angiography (5-13 months) confirmed complete occlusion in all patients who reached this milestone. All patients maintained their baseline clinical status. CONCLUSIONS The deployment of PEDs with concurrent partially dense coiling is safe and efficacious. This technique achieved early complete occlusion and endovascular reconstruction of the parent vessel, without inducing mass effect. Favorable midterm clinical results were observed in all patients.

BACKGROUND: Treatment of selected wide-neck internal carotid artery (ICA) bifurcation aneurysms remains challenging for clip reconstruction and for endovascular options. OBJECTIVE: To describe a new endovascular treatment technique for wide-neck ICA bifurcation (ICAb) aneurysms. METHODS: We have employed a treatment approach that uses both complete proximal occlusion and reversal of flow in the ipsilateral A1 segment, using different endovascular modalities such as coils, stent-assisted coiling, or flow diverters (FDs) plus coiling concomitantly. This endovascular technique may overcome the challenges of current treatments and high recanalization rates for coiled ICAb aneurysms. RESULTS: We treated four patients in whom we redirected the pre-existing flow in the supraclinoid ICA into the ipsilateral A1 and M1 segments, to a new unilateral, linear flow from the supraclinoid ICA solely into the ipsilateral M1 segment. This resulted in the establishment of flow from the contralateral A1 segment into the ipsilateral A1 segment, allowing supply of only demanding perforating arteries on this specific (ipsilateral) segment. This technique was not associated with any new neurological deficits or radiographic ischemia. The four patients reviewed were all treated using coils. One was treated with a standard stent. The other two were treated with a FD. CONCLUSIONS: We found that the proposed technique of flow modification can allow for hemodynamic conversion of ICAb to 'side-wall' aneurysm. In patients with good collateral flow through the anterior communicating complex, this treatment paradigm is safe and effective.

The authors report a case of primary CNS lymphoma located in the floor of the fourth ventricle that showed intense fluorescence after preoperative administration of 5-aminolevulinic acid. The authors believe that this is the first demonstration of a 5-aminolevulinic acid-induced fluorescence pattern in primary CNS lymphoma.

OBJECT/OBJECTIVE:Intraoperative seizures during awake craniotomy may interfere with patients' ability to cooperate throughout the procedure, and it may affect their outcome. The authors have assessed the occurrence of intraoperative seizures during awake craniotomy in regard to tumor location and the isocitrate dehydrogenase 1 (IDH1) status of the tumor. METHODS:Data were collected in 137 consecutive patients who underwent awake craniotomy for removal of a brain tumor. The authors performed a retrospective analysis of the incidence of seizures based on the tumor location and its IDH1 mutation status, and then compared the groups for clinical variables and surgical outcome parameters. RESULTS:Tumor location was strongly associated with the occurrence of intraoperative seizures. Eleven patients (73%) with tumor located in the supplementary motor area (SMA) experienced intraoperative seizures, compared with 17 (13.9%) with tumors in the other three non-SMA brain regions (p < 0.0001). Interestingly, there was no significant association between history of seizures and tumor location (p = 0.44). Most of the patients (63.6%) with tumor in the SMA region harbored an IDH1 mutation compared with those who had tumors in non-SMA regions. Thirty-one of 52 patients (60%) with a preoperative history of seizures had an IDH1 mutation (p = 0.02), and 15 of 22 patients (68.2%) who experienced intraoperative seizures had an IDH1 mutation (p = 0.03). In a multivariate analysis, tumor location was found as a significant predictor of intraoperative seizures (p = 0.002), and a trend toward IDH1 mutation as such a predictor was found as well (p = 0.06). Intraoperative seizures were not associated with worse outcome. CONCLUSIONS:Patients with tumors located in the SMA are more prone to develop intraoperative seizures during awake craniotomy compared with patients who have a tumor in non-SMA frontal areas and other brain regions. The IDH1 mutation was more common in SMA region tumors compared with other brain regions, and may be an additional risk factor for the occurrence of intraoperative seizures.

BACKGROUND:EC-IC bypass for the treatment of a hypoperfused hemisphere is currently the treatment of choice for symptomatic moyamoya patients. Use of the combination of direct (STA-MCA) and indirect (an STA branch lay-on bypass and flipped dural flaps; EDAS) EC-IC bypass is advocated as the optimal treatment option as it allows immediate augmentation of flow in the postoperative period while allowing the brain to acquire additional indirect flow in the long term. METHODS:We describe the technical nuances of a combined direct and indirect bypass in a 41-year-old woman with moyamoya syndrome diagnosed with transient ischemic attacks (TIAs) and cognitive decline. CONCLUSION/CONCLUSIONS:Combined direct and indirect bypass option should become a familiar treatment modality among vascular neurosurgeons. KEY POINTS/CONCLUSIONS:(1) Pay critical attention to not injuring the Superficial Temporal Artery, Parietal branch (STApb) while turning the skin incision anteriorly. Use the operating microscope to dissect the STApb. (2) Always mark the origin of the Superficial Temporal Artery, Frontal branch (STAfb) on the skin so that its location can be anticipated during STApb dissection. (3) When no frontal branch is available or if the frontal branch is of poor quality, the STApb can be used as a direct or indirect graft. (4) A craniotomy should be done 2-3 cm posterior to the course of the STApb to allow for adequate exposure for an indirect graft. (5) Manipulation of the donor vessels should be done with extreme care as spasm of the artery or intraluminal thrombosis may occur. Low cut flow in the direct graft should be interpreted with caution as vasospasm can result in significant temporary reduction of flow. (6) Aggressive distal dissection of the direct donor is a must. The distal 1-2 cm of the vessel should be cleaned of any loose tissue and be fishmouthed prior to anastomosis. (7) A blood-free field is mandatory. Perforators on the backside of the recipient should be sacrificed and cut to avoid backbleeding into the anastomotic segment during temporary occlusion. (8) When recirculating after the anastomosis has been completed, open the temporary clips on the recipient first. Backflow into the donor segment confirms a patent anastomosis. (9) Utilization of intraoperative angiography is not necessary as long as one utilizes flow measurements and ICG angiography. (10) Take great care with the bone flap reconstruction and the skin closure as the grafts can easily be compressed or sutured. Create a generous craniectomy in the bone flap to avoid any graft compression.