Ahead of Print: 3-D Angiography for AVM

Background: Accurate target delineation has significant impact on brain arteriovenous malformations (AVMs) obliteration, treatment success, and potential complications of stereotactic radiosurgery.

Objective: We compare the nidal contouring of AVMs using fused images of contrasted computerized tomography (CT) and magnetic resonance (MRI) with matched images of three-dimensional (3-D) cerebral angiography for Cyberknife radiosurgery (CKRS) treatment planning.

Methods: Between May 2009 and April 2012, 3-D cerebral angiography was integrated into CKRS target planning for thirty consecutive patients. The AVM nidal target volumes were delineated using fused CT and MRI scans versus fused CT, MRI, and 3-D cerebral angiography for each patient.

Ahead of Print: Is There a Shortage of Neurosurgeons in the United States?

Background: Neurosurgical workforce decision-making is typically driven by the 1 neurosurgeon per 100,000 population ratio proposed in 1977 in the Study on Surgical Services for the United States (SOSSUS) report. The actual ratio has always been higher than suggested.

Objective: We evaluated whether the 1:100,000 ratio from the SOSSUS report is still valid, whether there are enough neurosurgeons in the U.S. to meet patient needs, and whether demand is driven by patient need.

Methods: For our analysis, the distribution of practicing US neurosurgeons was merged with census data to yield density indices of neurosurgeons by state; a survey assessing practice characteristics was emailed to practicing neurosurgeons; and a compilation of job advertisements for U.S. neurosurgeons was evaluated.

Ahead of Print: Colloid Cyst Remnants

Background: Controversy surrounds the fate of cyst remnants following endoscopic colloid cyst resection.

Objective: Our study evaluated recurrence rates in patients with total endoscopic resection of colloid cysts versus those with coagulated cyst remnants.

Methods: Sixty-five consecutive patients and 67 procedures for endoscopic resection of colloid cysts from 1995 to 2011 were reviewed. Degree of resection was based upon intra-operative assessment and post-operative MRI. Recurrence rates were compared between patients with complete resection versus coagulated cyst remnants.

Ahead of Print: Neuropsychiatric Changes after Stereotactic Surgery

Background: Stereotactic central lateral thalamotomy (CLT) has been applied as a treatment for chronic intractable neuropathic pain. However, it is not clear whether this intervention influences the emotional and cognitive impairments observed in chronic neuropathic pain patients.

Objective: To investigate neuropsychological functions and emotional processing in patients with chronic neuropathic pain compared to healthy volunteers, and to explore the neuropsychiatric effect of the CLT.

Methods: We investigated pain ratings, cognitive functions, emotional processes, and personality variables before and after surgery in eight patients with intractable neuropathic pain. Patients were tested before and 3 months after CLT using neuropsychological tests, clinical scales for depression, anxiety, anhedonia and anger regulation, a personality test, and two experimental tasks testing the theory of mind as well as the ability to recognize facial emotional expressions. Nine age- and gender-matched control subjects were tested once using the same procedure.

Ahead of Print: Basilar Bifurcation in Peri-Mesencephalic Hemorrhage

Background: The angle of bifurcation of the basilar artery (BAB angle) is thought to influence the risk for development and rupture of aneurysms at this site. It is, however, unknown if the BAB angle also influences the incidence of angiographically negative peri-mesencephalic subarachnoid hemorrhage (PMSAH).

Objective: We performed a retrospective cross-sectional study comparing the BAB angle in a series of patients who presented with subarachnoid hemorrhage from a ruptured aneurysm at the top of the basilar artery (BSAH) with the BAB angle in a series of patients who presented with PMSAH.

Methods: Consecutive patients who presented to our institution with PMSAH or BSAH between Jan 1, 2005 and Dec 31, 2010 were studied. Patients with PMSAH were further subdivided into patients with classic PMSAH (CPMSAH) and those with non-classic PMSAH (NCPMSAH) based on initial head CT exams. In each patient, the BAB angle was measured on the standard cranial AP projections after vertebral artery injections.