✓ Fistulous communication between the vertebral artery and its surrounding venous plexus is rare. Two cases of vertebral arteriovenous fistula following anterior cervical spine surgery are reported. The anatomic relationships of the vertebral vessels, the radiographic findings, and the various therapeutic approaches to these lesions are discussed.
Report of two cases
G. Rees Cosgrove and Jacques Théron
G. Rees Cosgrove, Jean-Guy Villemure and Denis Melançon
✓ A case is presented of false intracranial aneurysm of traumatic origin which developed following direct surgical attack on a congenital anterior communicating artery aneurysm. The secondary aneurysm was discovered on the 25th postoperative day and was clipped at a subsequent procedure. The possible pathophysiology is discussed with respect to other direct vessel injuries.
W. Jeff Elias and G. Rees Cosgrove
Stephen B. Tatter and G. Rees Cosgrove
✓ Juxtafacet cysts of the lumbar spine have been reported with increasing frequency but their pathogenesis remains obscure. These cysts most frequently present with back pain, followed by chronic progressive radiculopathy or gradual onset of symptoms of spinal canal compromise. The authors report an unusual case of hemorrhage into a right L3–4 synovial cyst causing an acute cauda equina syndrome and describe its successful surgical treatment. The clinical, radiographic, and pathological features are discussed.
Aviva Abosch and G. Rees Cosgrove
An estimated 20% of patients with major depression are refractory to existing therapies. The purpose of this review is to provide a theoretical and neuroscientific framework in which to interpret new work in the field of surgical treatment for depression. This review focuses on existing clinical and imaging data, current disease models, and results of recent case reports and patient series that together may inform the construction of appropriate clinical trials for the surgical treatment of refractory depression.
Maya Harary, David J. Segar, Kevin T. Huang, Ian J. Tafel, Pablo A. Valdes and G. Rees Cosgrove
Focused ultrasound (FUS) has been under investigation for neurosurgical applications since the 1940s. Early experiments demonstrated ultrasound as an effective tool for the creation of intracranial lesions; however, they were limited by the need for craniotomy to avoid trajectory damage and wave distortion by the skull, and they also lacked effective techniques for monitoring. Since then, the development and hemispheric distribution of phased arrays has resolved the issue of the skull and allowed for a completely transcranial procedure. Similarly, advances in MR technology have allowed for the real-time guidance of FUS procedures using MR thermometry. MR-guided FUS (MRgFUS) has primarily been investigated for its thermal lesioning capabilities and was recently approved for use in essential tremor. In this capacity, the use of MRgFUS is being investigated for other ablative indications in functional neurosurgery and neurooncology. Other applications of MRgFUS that are under active investigation include opening of the blood-brain barrier to facilitate delivery of therapeutic agents, neuromodulation, and thrombolysis. These recent advances suggest a promising future for MRgFUS as a viable and noninvasive neurosurgical tool, with strong potential for yet-unrealized applications.
Heather S. Spader, Linda Ratanaprasatporn, John F. Morrison, Jonathan A. Grossberg and G. Rees Cosgrove
Programmable shunts have a valuable role in the treatment of patients with hydrocephalus, but because a magnet is used to change valve settings, interactions with external magnets may reprogram these shunts. Previous studies have demonstrated the ability of magnetic toys and iPads to erroneously reprogram shunts. Headphones are even more ubiquitous, and they contain an electromagnet for sound projection that sits on the head very close to the shunt valve. This study is the first to look at the magnetic field emissions of headphones and their effect on reprogrammable shunt valves to ascertain whether headphones are safe for patients with these shunts to wear.
In this in vitro study of the magnetic properties of headphones and their interactions with 3 different programmable shunts, the authors evaluated Apple earbuds, Beats by Dr. Dre, and Bose QuietComfort Acoustic Noise Cancelling headphones. Each headphone was tested for electromagnetic field emissions using a direct current gaussmeter. The following valves were evaluated: Codman Hakim programmable valve, Medtronic Strata II valve, and Aesculap proGAV. Each valve was tested at distances of 0 to 50 mm (in 5-mm increments) from each headphone. The exposure time at each distance was 1 minute, and 3 trials were performed to confirm results at each valve setting and distance.
All 3 headphones generated magnetic fields greater than the respective shunt manufacturer's recommended strength of exposure, but these fields did not persist beyond 5 mm. By 2 cm, the fields levels were below 20 G, well below the Medtronic recommendation of 90 G and the Codman recommendation of 80 G. Because the mechanism for the proGAV is different, there is no recommended gauss level. There was no change in gauss-level emissions by the headphones with changes in frequency and amplitude. Both the Strata and Codman-Hakim valves were reprogrammed by direct contact (distance 0 mm) with the Bose headphones. When a rotation component was added, all 3 headphones reprogrammed the Strata and Codman-Hakim valves at 0 mm. At all distances above 0 mm, the headphones did not affect the shunts. The proGAV valve was not affected by headphones at any distance.
Although all the headphones studied generated significant gauss fields at distances less than 5 mm, the programmable valve settings only changed at a distance of 0 mm (i.e., with direct contact). Given the subcutaneous location of the valve, the authors conclude that is highly unlikely that commercially available or customary headphones can contribute to the reprogramming of shunts.
William T. Curry Jr., G. Rees Cosgrove, Bradley R. Buchbinder and Robert G. Ojemann
Intraventricular meningiomas of the lateral ventricle occur relatively rarely, but they are often large at the time of detection and present more commonly on the left side. Although the ability to resect these tumors safely has greatly improved over time, standard surgical approaches often traverse cortex close to areas of specific cortical function. Precise cortical mapping of language and sensorimotor cortices can be accomplished noninvasively by using functional magnetic resonance (fMR) imaging. The authors used fMR imaging in planning the cortical incision for resection of a large intraventricular trigone meningioma in the dominant hemisphere of a patient who, postoperatively, suffered no aphasia or hemiparesis. The authors discuss the advantages of mapping cortical function preoperatively with fMR imaging when approaching intraventricular lesions.