Search Results

You are looking at 1 - 10 of 162 items for

  • Author or Editor: Aaron A. Cohen-Gadol x
Clear All Modify Search
Restricted access

Zachary A. Seymour and Aaron A. Cohen-Gadol

Although recent efforts to advance the treatment of gliomas through radiotherapy and chemotherapy may seem to be a relatively new area of growth and development, these efforts have been in progress since the therapeutic potential of radiation therapy was discovered in the late 19th century. Cushing's use of brachytherapy has been mentioned several times in the literature without receiving an appropriate in-depth analysis. The reasoning behind Cushing's initial use of brachytherapy was not fully examined, and a close analysis of the outcomes of this therapy was not made. In addition, Cushing's use of his “radium bomb” occurred more commonly than the 3 cases previously documented. The authors reviewed all the patient records available at the Cushing Brain Tumor Registry—which represents the most complete series of patient records from the Cushing era—and selected those patients who underwent treatment with Cushing's “radium bomb.” The authors place these early attempts to optimize interstitial radiation of brain tumors in their historical perspective.

Restricted access

Aaron A. Cohen-Gadol and Dennis D. Spencer

✓ The temporal lobe is the most common site of partial epilepsy that is amenable to surgical therapy, and therefore ictal localization in this region is important. The authors describe the application of an anteromedial subdural strip electrode for the evaluation of epilepsy originating from the medial temporal lobe. This strip is advanced around the temporal pole and underneath the lesser wing of the sphenoid bone as it follows the medial temporal lobe contour. The advantages of this method of placement are the consistent path and reliable final position of the strip along the medial basal temporal lobe surface. This method allows adequate coverage of the parahippocampal gyrus along its long axis extending posterior to the level of the collicular plate. This technique has been used with no complications during intracranial monitoring of more than 100 patients with presumed temporal lobe epilepsy.

Restricted access

Aaron A. Cohen-Gadol and Dennis D. Spencer

✓Development of posterior fossa surgery remains Harvey Cushing's hallmark contribution to pediatric neurosurgery. During the era before Cushing, posterior fossa lesions were considered inoperable, and only osseous decompressive surgery was offered. The evolution of Cushing's surgical expertise from subtemporal decompressions to total extirpation of vascular fourth ventricular tumors, combined with a dramatic decrease in his operative mortality rate, reflects the maturation of modern neurosurgical techniques. A comprehensive review of the medical records of Cushing's pediatric patients treated between 1912 and 1932 revealed that procedures such as lateral ventricular puncture (to decrease cerebellar herniation), transvermian approach to midline tumors, and electrocoagulation were the key factors punctuating the path to his pioneering achievements in posterior fossa surgery. The outcome of such operations was improved by his recognition of the importance of tumor mural nodule in cyst recurrence, as well as elucidation of the histogenesis of pediatric posterior fossa tumors to tailor treatment including radiotherapy.

Restricted access

Aaron A. Cohen-Gadol and Dennis D. Spencer

✓ The development of surgical techniques for the treatment of intracranial aneurysms has paralleled the evolution of the specialty of neurological surgery. During the Cushing era, intracranial aneurysms were considered inoperable and only ligation of the carotid artery was performed. Cushing understood the limitations of this approach and advised the need for a more thorough understanding of aneurysm pathology before further consideration could be given to the surgical treatment of cerebral aneurysms. Despite his focus on brain tumors, Cushing's contributions to the discipline of neurovascular surgery are of great importance. With the assistance of Sir Charles Symonds, Cushing described the syndrome of subarachnoid hemorrhage. He considered inserting muscle strips into cerebral aneurysms to promote aneurysm sac thrombosis and designed the “silver clip,” which was modified by McKenzie and later used by Dandy to clip the first intracranial aneurysm. Cushing was the first surgeon to wrap aneurysms in muscle fragments to prevent recurrent hemorrhage. He established the foundation on which pioneers such as Norman Dott and Walter Dandy launched the modern era of neurovascular surgery.

Restricted access

Aaron A. Cohen-Gadol and Dennis D. Spencer

✓ The surgical treatment of cerebrovascular malformations intrigued early neurosurgeons. Cushing defined vascular malformations as tumors arising from cerebral blood vessels. He successfully resected the first arteriovenous malformation 3 years after it had been irradiated. In the absence of angiography, the pathoanatomy of these lesions remained elusive and early techniques such as cortical vein ligation proved catastrophic. Cushing demonstrated the favorable results of radiation treatments on vascular malformations and advocated decompressive craniectomy followed by radiotherapy. He ligated cortical feeding vessels and external carotid arteries with an improved understanding of the angioarchitecture of vascular malformations. He stressed the importance of preoperative diagnosis because the radical resection of nonirradiated vascular malformations challenged the limitations of the available neurosurgical armamentarium.

Restricted access

Aaron A. Cohen-Gadol and Bruce E. Pollock

Object

The authors present the results of stereotactic radiosurgery performed in a consecutive series of children with arteriovenous malformations (AVMs) and analyze factors associated with successful radiosurgery for this condition.

Methods

Between 1990 and 2001, 38 patients 18 years of age or younger underwent radiosurgery for AVMs. The median patient age was 15 years; 20 patients (53%) had experienced a prior hemorrhage. Twenty-seven AVMs (71%) were Spetzler–Martin Grade III or higher; 16 patients (42%) had AVMs located in the basal ganglia, thalamus, or brainstem. The median AVM volume was 3.4 cm3. The median radiosurgery-based AVM score was 1.08 according to the following formula: AVM score = 0.1 volume (cm3) + 0.02 × age (years) + 0.3 × location (frontal/temporal = 0; parietal/occipital/corpus callosum/cerebellar = 1; basal ganglia/thalamus/brainstem = 2). The median follow-up period was 42 months.

One patient (3%) had an intraventricular hemorrhage 26 months after radiosurgery but experienced no new deficit. No patient had a permanent radiation-related complication after radiosurgery. Twenty-six patients (68%) had excellent outcomes (as defined by complete obliteration of the AVM with no new deficit) after radiosurgical treatment (21 cases determined using angiography and five using magnetic resonance imaging). Twelve patients (32%) remained unchanged (incomplete obliteration but no new deficit). Univariate analysis found that patient age, AVM volume, location, or Spetzler–Martin grade did not correlate with excellent outcomes. Patients whose radiosurgery-based AVM scores were 1 or lower experienced an excellent outcome more frequently than patients with an AVM score higher than 1 (88% compared with 52%, p = 0.03).

Conclusions

Radiosurgery was successful in the treatment of the majority of pediatric patients suffering from AVMs, and morbidity levels were minimal. The radiosurgery-based AVM grading scale accurately predicted these outcomes. Children whose AVMs are obliterated after radiosurgery should undergo repeated angiography after they reach adulthood to rule out the possibility of a recurrent nidus that would expose them to an ongoing risk of hemorrhage.

Free access

Jonathan Russin and Aaron A. Cohen-Gadol

Free access

Roberto Rey-Dios and Aaron A. Cohen-Gadol

Insular gliomas were traditionally considered a nonsurgical entity due to the high morbidity associated with resection. For the past 20 years, advances in microsurgical and brain mapping techniques have allowed neurosurgeons to resect insular gliomas with acceptable morbidity rates. Maximizing the extent of resection is nowadays the goal of surgery since this has proven to be an independent factor contributing to longer survival. Despite much progress, insular tumors remain a challenge for the neurosurgeon due to the complex anatomy of the region and technical expertise required to minimize morbidity during surgery. Herein, the authors describe the current surgical nuances, based on their experience and a literature review, that will allow the surgeon to achieve a thorough resection while ensuring patient safety. The key factors for successful surgery in the insular region include detailed knowledge of the surgical anatomy, mastery of the nuances of cortical and subcortical mapping methods, and meticulous microsurgical technique.