✓ There is a growing body of evidence in the literature suggesting that cavernous malformations of the central nervous system may develop after neuraxis irradiation. The authors discuss the case of a 17-year-old man who presented with progressive back pain and myelopathy 13 years after undergoing craniospinal irradiation for a posterior fossa medulloblastoma. Spinal magnetic resonance (MR) imaging, performed at the time of his initial presentation with a medulloblastoma, demonstrated no evidence of a malformation. Imaging studies and evaluation of cerebrospinal fluid revealed no evidence of recurrence or dissemination. Spinal MR imaging demonstrated an extensive lesion in the thoracic spine with an associated syrinx suggestive of a cavernous malformation. A thoracic laminectomy was performed and the malformation was successfully resected. Pathological examination confirmed the diagnosis. The patient did well after surgery and was ambulating without assistance 6 weeks later. To the best of the authors' knowledge, this is the second reported case in the literature and the first in the young adult age group suggesting the de novo development of cavernous malformations in the spinal cord after radiotherapy. An increased awareness of these lesions and close follow-up examination are recommended in this setting.
Case report and review of the literature
Prithvi Narayan and Daniel L. Barrow
Brian M. Howard, Ranliang Hu, Jack W. Barrow, and Daniel L. Barrow
Intracranial aneurysms confer the risk of subarachnoid hemorrhage (SAH), a potentially devastating condition, though most aneurysms will remain asymptomatic for the lifetime of the patient. Imaging is critical to all stages of patient care for those who harbor an unruptured intracranial aneurysm (UIA), including to establish the diagnosis, to determine therapeutic options, to undertake surveillance in patients who elect not to undergo treatment or whose aneurysm(s) portends such a low risk that treatment is not indicated, and to perform follow-up after treatment. Neuroimaging is equally as important in patients who suffer an SAH. DSA remains the reference standard for imaging of intracranial aneurysms due to its high spatial and temporal resolution. As noninvasive imaging technology, such as CTA and MRA, improves, the diagnostic accuracy of such tests continues to increasingly approximate that of DSA. In cases of angiographically negative SAH, imaging protocols are necessary not only for diagnosis but also to search for an initially occult vascular lesion, such as a thrombosed, ruptured aneurysm that might be detected in a delayed fashion. Given the crucial role of neuroimaging in all aspects of care for patients with UIAs and SAH, it is incumbent on those who care for these patients, including cerebrovascular neurosurgeons, interventional neurologists and neuroradiologists, and diagnostic radiologists and neurointensivists, to understand the role of imaging in this disease and how individual members of the multispecialty team use imaging to ensure best practices to deliver cutting-edge care to these often complex cases. This review expounds on the role of imaging in the management of UIAs and ruptured intracranial aneurysms and in the workup of angiographically negative subarachnoid hemorrhage.
Steven L. Giannotta and DanieL L. Barrow
Daniel L. Barrow, Austin R. T. Colohan, and Robert Dawson
✓ Intradural perimedullary arteriovenous fistulas (Type IV spinal cord arteriovenous malformations (AVM's)) are rarely reported in the literature and occasionally are classified together with Type II AVM's as intradural spinal cord AVM's. The authors report eight cases of Type IV spinal cord AVM's managed over a 2-year period. Seven of these AVM's were surgically obliterated, with intraoperative angiography being used as an adjunct; one other patient was managed using endovascular therapy. One of these lesions was definitely and another possibly the result of trauma; a malformation in a newborn infant was clearly congenital. The authors believe that the pathophysiological mechanisms and anatomical features of these lesions represent a unique spinal vascular anomaly that must be recognized angiographically to plan appropriate therapy.
Brian M. Howard and Daniel L. Barrow
Many brain arteriovenous malformations (AVMs) derive dural blood supply, while 10%–15% of dural arteriovenous fistulas (dAVFs) have pial arterial input. To differentiate between the two is critical, as treatment of these entities is diametrically opposed. To treat dAVFs, the draining vein(s) is disconnected from feeding arteries, which portends hemorrhagic complications for AVMs. The authors present an operative video of a subtle cerebellar AVM initially treated as a dAVF by attempted embolization through dural vessels. The lesion was subsequently microsurgically extirpated. The authors show a comparison case of an AVM mistaken for a dAVF and transvenous embolization that resulted in a fatal hemorrhage.
The video can be found here: https://youtu.be/eDeiMrGoE0Q
Luis M. Tumialán, C. Michael Cawley, and Daniel L. Barrow
✓ The authors report the case of a 53-year-old woman in whom a T1–T2 spinal arachnoid cyst with associated arachnoiditis developed, compressing the thoracic spinal cord 1 year after the patient had suffered a Hunt and Hess Grade IV subarachnoid hemorrhage (SAH). Development of spinal arachnoiditis with or without an arachnoid cyst is a rare complication of aneurysmal SAH. Risk factors may include posterior circulation aneurysms, the extent and severity of the hemorrhage, and the need for cerebrospinal fluid diversion. Surgical drainage, shunt placement, or cyst excision, when possible, is the mainstay of treatment.
Daniel L. Barrow, Junichi Mizuno, and George T. Tindall
✓ The authors have reviewed the results of transsphenoidal microsurgical management in 69 patients with prolactin-secreting pituitary adenomas who had preoperative serum prolactin levels over 200 ng/ml. The patients were divided into three groups based on their preoperative serum prolactin levels: over 200 to 500 ng/ml (Group A); over 500 to 1000 ng/ml (Group B); and over 1000 ng/ml (Group C). The percentage of successful treatment (“control rate”) was 68%, 30%, and 14%, respectively, in these three groups of patients. Based on these results, the authors offer guidelines for the management of patients with prolactin-secreting pituitary adenomas associated with exceptionally high serum prolactin levels. The surgical control rate of 68% in Group A seems to justify surgery for these patients, while primary medical care with bromocriptine is recommended for most patients with serum prolactin levels over 500 ng/ml.
Daniel L. Barrow, Gustavo Pradilla, and D. Jay McCracken
Intracranial blister aneurysms are difficult to treat cerebrovascular lesions that typically affect the anterior circulation. These rare aneurysms can lead to acute rupture which usually cannot be treated via endovascular methods, but still require urgent surgical intervention. Surgical options are limited given their unique pathology and often require a combination of wrapping and clip reconstruction. In this video we present two patients with acute subarachnoid hemorrhage secondary to ruptured blister aneurysms. We demonstrate several surgical techniques for repairing the vascular defect with and without intraoperative rupture.
The video can be found here: http://youtu.be/nz-JM45uKQU.
Daniel L. Barrow, Foad Nahai, and Alan S. Fleischer
✓ Musculocutaneous (skin-muscle) flaps have been used predominantly by plastic surgeons for a variety of reconstructive purposes. With the advent of microvascular techniques, the area to be reconstructed is no longer limited to the arc of rotation of the vascular pedicle of the muscle. Instead, the muscle and overlying skin that is best suited for the reconstructive procedure may be dissected out as a free flap, with microvascular anastomosis of an arterial supply and venous drainage to locally existing vessels.
This report demonstrates the usefulness of musculocutaneous free flaps in the repair of large defects of the scalp, cranium, and dura after trauma or resection of invasive neoplasms. The authors describe the use of a latissimus dorsi free musculocutaneous flap in eight patients who would have required multiple operations to provide coverage by other techniques. There have been no major complications, and adequate repair has been accomplished, even in cases involving exposed brain.