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BACKGROUND Aneurysm clipping simulation models are needed to provide tactile feedback of biological vessels in a nonhazardous but surgically relevant environment. OBJECTIVE To describe a novel system of simulation models for aneurysm clipping training and assess its validity. METHODS Craniotomy models were fabricated to mimic actual tissues and movement restrictions experienced during actual surgery. Turkey wing vessels were used to create aneurysm models with patient-specific geometry. Three simulation models (middle cerebral artery aneurysm clipping via a pterional approach, anterior cerebral artery aneurysm clipping via an interhemispheric approach, and basilar artery aneurysm clipping via an orbitozygomatic pretemporal approach) were subjected to face, content, and construct validity assessments by experienced neurosurgeons (n = 8) and neurosurgery trainees (n = 8). RESULTS Most participants scored the model as replicating actual aneurysm clipping well and scored the difficulty of clipping as being comparable to that of real surgery, confirming face validity. Most participants responded that the model could improve clip-applier-handling skills when working with patients, which confirms content validity. Experienced neurosurgeons performed significantly better than trainees on all 3 models based on subjective (P = .003) and objective (P

BACKGROUND The influence of the surgeon's preoperative goal regarding the extent of tumor resection on patient outcomes has not been carefully studied among patients with nonfunctioning pituitary adenomas. OBJECTIVE To analyze the relationship between surgical tumor removal goal and patient outcomes in a prospective multicenter study. METHODS Centrally adjudicated extent of tumor resection (gross total resection [GTR] and subtotal resection [STR]) data were analyzed using standard univariate and multivariable analyses. RESULTS GTR was accomplished in 148 of 171 (86.5%) patients with planned GTR and 32 of 50 (64.0%) patients with planned STR (P = .001). Sensitivity, specificity, positive predictive value, and negative predictive value of GTR goal were 82.2, 43.9, 86.5, and 36.0%, respectively. Knosp grade 0-2, first surgery, and being an experienced surgeon were associated with surgeons choosing GTR as the goal (P

As described by Cushing1 in the chiasmatic syndrome, tuberculum sellae meningiomas induce progressive asymmetrical, incongruous visual loss, which would lead to blindness. The surgical removal of these lesions has been rewarding in regard to visual preservation, or recovery, and has passed the test of time. Optic canal extension, in one or both canals, is a consistent feature of these tumors, and removing the tumor from the optic canals is paramount in the treatment of these lesions.2 Despite the small target volume, radiosurgery is not applicable because of the lack of safe distance from the optic pathways. Tuberculum sella meningioma has been distinguished with good surgical outcomes and low recurrence rates; thus, Simpson grade I removal (tumor, dura, and bone invasion) confers a prospect of cure. Safe and successful resection of tuberculum meningiomas is achieved through the skull base supraorbital approach3 with several critical objectives: (1) visualization of the tumor without brain retraction; (2) 270° opening of the optic canal proximally and distally for safe tumor removal; (3) preservation of the vascular supply to the optic pathways and pituitary; (4) microsurgical dissection under high magnification on a short working distance to the encased carotid and anterior cerebral arteries; (5) complete resection of involved dura and bone at the skull base, particularly laterally; and (6) a robust skull base reconstruction with a vascularized pericranial flap.4 We present the case of a 45-yr-old female with a tuberculum sella meningioma who underwent Simpson grade I removal with an uneventful outcome. The patient consented for surgery. Image at 2:59 reprinted with permission from Al-Mefty O, Operative Atlas of Meningiomas. Vol 1, © LWW, 1998; Image at 9:33 public domain.4.

Complete resection of skull base chondrosarcomas offers the potential for a durable, or even lifelong, cure and is best achieved at the first surgery.1,2 When a skull base chondrosarcoma is located at the upper clivus and in the interpeduncular cistern and invading laterally toward the petrous apex and cavernous sinus, the traditional approaches, ie, endonasal endoscopic or middle fossa approaches, are not adequate for the exposure and resection. The transcavernous sinus approach has been utilized to remove tumor from the cavernous sinus and as a corridor to the interpeduncular cistern and upper clivus, originally described for the clipping of basilar apex aneurysms. We present a case of a chondrosarcoma centered in the upper clivus and eroding the right posterior clinoid, analogous to the location of a giant basilar apex aneurysm. Detailed study of the tumor extension, bony invasion, and relationship with neuroanatomy dictated the most effective surgical approach.3,4 Neuronavigation and intraoperative magnetic resonance imaging (MRI) facilitated the gross total resection of the tumor in the Advanced Multimodality Image-Guided Operating (AMIGO) suite. Achieving a gross total tumor removal of this World Health Organization (WHO) grade I chondrosarcoma, adjuvant irradiation can be withheld1 and the patient monitored with serial imaging. The patient did well after the surgery. The patient consented for surgery and the use of photography.

Giant basilar apex aneurysms are associated with significant therapeutic challenges.1-6 Multiple techniques exist to treat giant basilar apex aneurysms, including direct clipping, stent-assisted coil embolization, and proximal occlusion with bypass revascularization.7-9 Hypothermic circulatory arrest was a useful adjunct for surgical repair of these aneurysms but has been abandoned because of associated risks.10,11 Rapid ventricular pacing can achieve similar aneurysm softening with minimal risks and assist in clip occlusion. This case illustrates clip occlusion of a giant, partially thrombosed, previously stent-coiled basilar apex aneurysm in a 15-yr-old boy with progressive cranial neuropathies and sensorimotor impairment. Although a wire was placed preoperatively for ventricular pacing, it was not needed during the procedure. Patient consent was obtained. A right-sided orbitozygomatic craniotomy transcavernous approach with anterior and posterior clinoidectomies was performed. The basilar quadrification was dissected, and proximal control was obtained. After aneurysm trapping, the aneurysm was incised and thrombectomized using an ultrasonic aspirator. Back-bleeding from the aneurysm was anticipated, and ventricular pacing was ready, but back-bleeding was minimal. With the coil mass left in place, stacked, fenestrated clips were applied in a tandem fashion to occlude the aneurysm neck. Indocyanine green videoangiography confirmed occlusion of the aneurysm and patency of parent and branch arteries. The patient was at a neurological baseline after the operation, with improvement in motor skills and cognition at 3-mo follow-up. This case demonstrates the use of trans-sylvian-transcavernous exposure, rapid ventricular pacing, and thrombectomy amid previous coils and stents to clip a giant, thrombotic basilar apex aneurysm. Used with permission from Barrow Neurological Institute, Phoenix, Arizona.

Preoperative careful evaluation of the sigmoid transverse sinus and its tributary veins is paramount for the safe surgical planning of petroclival lesions.1,2 When the vein of Labbé is running within the tentorium, classic petrosal approach involving transection of the tentorium is modified to avoid the risk of postoperative morbid temporal lobe venous infarcts.1-3 Thus, the surgical plan should be tailored to the specific patient anatomy as demonstrated in the presented case during which a transmastoid approach was followed, in the same surgical setting, by a middle fossa approach to resect a large petroclival clear cell meningioma with extension into Meckel cave. These meningiomas are WHO grade II tumors with a propensity to local recurrence and cerebrospinal fluid seeding.4 SMARCE1 mutations define this subtype of meningioma, with frequent familial inheritance, and predispose patients to both skull base and spinal clear cell meningiomas.5,6 Maximal surgical resection is the best initial treatment option allowing to withhold or delay the use of radiation in tumors frequently encountered in young patients.7 In this report, we demonstrate the microsurgical techniques deployed to achieve maximal resection of a petroclival clear cell meningioma and associated lumbar and sacral spinal meningiomas in a 20-yr-old patient with a familial SMARCE1 mutation. The patient agreed to the surgical intervention and to the use of her image.

Giants of neurosurgery have made contributions that might at times seem to be minor maneuvers but have a major impact on safe surgery, such as Sugita and Kobayashi's description of the preservation of the bridging sagittal veins.1 The interhemispheric approach is haunted by risk to the bridging veins and resultant venous infarction. At the midsegment, this could produce devastating neurological deficits.2 This is an especially critical factor in falcine meningiomas in which the location of the tumor narrows the options for the surgical corridor, particularly if an additional falcine margin, "Grade Zero" resection, is to be performed.3 Detailed preoperative neuroimaging workup is required to plan the appropriate surgical strategy and minimize risk for venous complications. This may include magnetic resonance or computed tomography venogram, dynamic computed tomography angiography,4 or in some cases formal angiography to assess the relationship with the superior sagittal sinus, the anatomy of parasagittal bridging veins in relation to the lesion, and the patterns of collateral venous drainage. While bridging veins may be displaced, compressed, or obscured by tumor involvement,5 microsurgical technique can facilitate the safe identification and preservation of this crucial anatomy. Bridging veins are separated from the underlying cortex to a distance from the sinus, allowing for improved relaxation of the ipsilateral cortex, without venous compromise.1,6 Herein, we demonstrate a case of a large falcine meningioma with a "Grade Zero" resection, with mobilization of the parasagittal bridging veins to develop the interhemispheric surgical corridor. The patient consented for surgery.

Background External ventricular drains (EVDs) are routinely placed as part of the management of intracranial hypertension. Pseudoaneurysm formation after EVD placement is a rare complication that can occur as a result of direct trauma to the cerebral vasculature. Prompt recognition and treatment may prevent future rupture. Objective To present our management strategy of a unique case of pseudoaneurysm formation in the context of the medical literature on these rare complications. Methods An EVD was placed in a 58-year-old female patient who presented with intracranial hypertension after subarachnoid hemorrhage secondary to a ruptured posterior communicating artery aneurysm before coiling of the aneurysm. On postbleed day 10, a pseudoaneurysm was identified in the distal anterior cerebral artery adjacent to the EVD tract. Results The pseudoaneurysm was successfully treated with surgical resection. Conclusion Pseudoaneurysm formation after EVD placement is a rare but serious complication. We do not recommend routine screening for this complication; however, further investigation may be warranted when a delayed EVD tract hemorrhage is encountered. Prompt treatment of pseudoaneurysms is necessary to prevent future hemorrhage.

BACKGROUND Blister-like aneurysms (BLAs) are challenging lesions that require unique microsurgical strategies. BLAs are predominantly found along the internal carotid artery; however, BLAs of the basilar artery are a rare subset that requires a modified treatment strategy. OBJECTIVE To discuss the microsurgical management and review the long-term outcomes of patients with BLAs of the basilar artery. METHODS We retrospectively reviewed the surgical technique, postoperative results, and long-term outcomes of all patients with basilar artery BLAs treated at our institution from 2005 to 2011. RESULTS Four patients with basilar artery BLAs were identified over this 6-year interval. All 4 patients were treated by direct microsurgical clipping. A thin layer of cotton reinforcement was used beneath the clip tines to minimize the risk of clip slippage in 2 of 4 patients; 1 patient required adjunctive endovascular stent placement for residual aneurysm after clipping. Complete obliteration of all aneurysms was achieved, and there has been no recurrence at mean clinical follow-up of 72 months (median, 74.5; range, 37-103) and imaging follow-up of 48 months (median, 54; range 12-72). CONCLUSION Direct clipping with or without cotton reinforcement can obliterate basilar BLAs with excellent long-term outcomes. Clip wrapping is not an option for these lesions given the proximity to perforating branches. Endovascular techniques provide a useful adjunctive strategy; however, risks with antiplatelet therapy in the acute subarachnoid hemorrhage period must be considered.