Kennith F. Layton

Transorbital Puncture for the Treatment of Cavernous Sinus Dural Arteriovenous Fistulas

Summary: This report describes a series of patients for whom dural arteriovenous fistulae (DAVFs) of the cavernous sinus were successfully embolized using a percutaneous, transorbital technique to directly cannulate the cavernous sinus. A vascular access needle and catheter are percutaneously advanced along the inferolateral aspect of the orbit to access the cavernous sinus via the superior orbital fissure. Safe and effective embolization is achieved without the need for a surgical cut-down.

Balloon-Assisted Coiling of Intracranial Aneurysms: Evaluation of Local Thrombus Formation and Symptomatic Thromboembolic Complications

BACKGROUND AND PURPOSE: Remodeling balloons are used to assist in endovascular coiling of aneurysms. We evaluated our experience with balloon-assisted coiling (BAC) in an attempt to determine whether this technique increased the rate of thrombus formation or symptomatic thromboembolic complications. MATERIALS AND METHODS: In 3 years, we treated 221 patients with intracranial aneurysms. Statistical analysis was performed to assess whether BAC increased the rate of thrombus formation or symptomatic thromboembolic complications. Patient demographics, aneurysm size, location, neck width, antiplatelet therapy, and rupture status were evaluated. RESULTS: We detected no statistically significant difference in rates of thrombus formation (14% versus 9% with and without BAC, respectively, P = 0.35) or symptomatic thromboembolic events (7% versus 5% with and without BAC, respectively, P = 0.76), though our power to detect small differences was limited. There was also no correlation with age, sex, rupture status, aneurysm size, or location. There was a significant increase in the rates of thrombus formation (6% versus 16%, P = 0.02) and symptomatic thromboembolic complications (3% versus 10%, P = 0.04) in aneurysms that were classified as narrow- or wide-necked, respectively. The use of clopidogrel was associated with a decrease in the rate of complications (P = 0.01). CONCLUSION: In this series, we detected no significant increase in the rates of either intraprocedural thrombus formation or symptomatic thromboembolic events in patients treated with BAC. Larger studies are required to confirm our observations. Wide-necked aneurysms were independently associated with increased rates of thrombus formation and symptomatic thromboembolic complications, whereas the use of clopidogrel was protective (P = 0.01).

Vertebral Endplate Fractures: An Indicator of the Abnormal Forces Generated in the Spine After Vertebroplasty

Vertebroplasty alters spinal biomechanics and may lead to incident vertebral fractures. The endplate localization of prevalent and incident fractures was evaluated in 86 patients. In the absence of vertebroplasty, superior endplate fractures predominate. After the procedure, inferior endplate fractures are disproportionately common in adjacent vertebrae immediately above the treated level, potentially supporting a causative relationship between vertebroplasty and incident fractures.

Nonenhancing tumors of the spinal cord

OBJECT Enhancement of pathological entities in the central nervous system is a common finding when the blood-brain barrier has been compromised. In the brain, the presence or absence of gadolinium enhancement is often an indicator of tumor invasiveness and/or grade. In the spinal cord, however, contrast enhancement has been shown in all tumor types, regardless of grade. In this study the authors explore the incidence of nonenhancing tumors of the spinal cord and the clinical course of patients with these lesions. METHODS A retrospective analysis was conducted in which investigators examined the patterns of enhancement of histologically proven intramedullary spinal cord tumors that had been evaluated at the Mayo Clinic between 1998 and 2002. The tumors that did not enhance were the subject of this report. RESULTS A total of 130 patients with intramedullary tumors were evaluated. Of those, 11 patients (9%) had tumors that did not enhance. Histologically, a majority of tumors were astrocytomas (eight low-grade and two high-grade lesions); one tumor was a subependymoma. Morphologically, most of the tumors were diffuse and none had associated cysts. Tumors spanned from two to seven levels and were located throughout the spinal cord (four cervical, three cervicothoracic, one thoracic, and three thoracolumbar). Biopsy procedures were performed in eight patients, subtotal resection was performed in two, and gross-total resection in one. After a mean follow-up period of 19 months, tumors remained stable in eight patients but progressed in three, two of whom died. CONCLUSIONS A number of intramedullary spinal cord tumors will not enhance after addition of contrast agents. The absence of enhancement does not imply the absence of tumor.

Ruptured intracranial dermoid cyst

Rupture of an intracranial dermoid cyst is a rare event with considerable associated morbidity and potential mortality. We present a case of intracranial rupture of a dermoid cystic tumor with consequent dissemination of subarachnoid fat droplets resulting in acute aseptic chemical meningitis. Radiographic findings, operative treatment, and pathologic features are described.

Balloon-assisted coiling through a 5-French system

IntroductionWe present a catheter technique that utilizes a 5F system for the purpose of balloon-assisted coiling in the setting of intracranial aneurysms.MethodsA standard 5F short sheath is placed in the common femoral artery, and a 5F diagnostic catheter is placed through the sheath and used for selective vessel angiography. When endovascular intervention is pursued, the diagnostic catheter is placed in the appropriate vessel and systemic heparinization is ensured. Over an exchange length wire, the 5F vertebral catheter and 5F short sheath are exchanged for a 5F Shuttle (Cook) sheath. We then routinely place a 10, 14 or 18 microcatheter over an appropriately gauged microguidewire into the aneurysm. As needed, balloon catheters are then placed across the neck of the aneurysm for remodeling purposes. During the course of the procedure, control angiography is performed through the Shuttle sheath. Following the placement of coils, the microcatheter and balloon catheter are removed and a final biplane image is obtained via the 5F Shuttle sheath.ResultsThis technique has been employed in 15 patients who required balloon-assisted coiling of an intracranial aneurysm. There were no technical difficulties or arterial access site complications from the procedures. Catheter mobility and torque were not affected, nor was the quality of our imaging.ConclusionWe conclude that this small-diameter system provides ample “room” for catheter placement and interventional treatment while reducing the known risks of postprocedural complications. Angiographic images remain excellent and are comparable to those obtained by larger catheters.

Cerebral aneurysm perforations during treatment with detachable coils. Use of remodelling balloon inflation to achieve hemostasis

Perforation of intracranial aneurysms during endovascular treatment with platinum micro-coils is a well-known and serious complication reported to occur in 2–4% of patients. Inflation of a remodelling balloon across the aneurysm neck or within the proximal parent vessel is an additional technique that theoretically might be useful to reduce flow within the aneurysm and achieve hemostasis. In the case reports that follow, we present our experience using this technique for managing intraprocedural aneurysm rupture.

Papillary tumor of the pineal region

Presented is a patient with papillary tumor of the pineal region (PTPR), an uncommon and recently recognized neoplasm. As its name implies, PTPR does not arise from the pineal gland itself. The cell of origin is thought to be the specialized ependymocytes of the subcommissural organ. Primary tumors of the pineal region include pineal parenchymal neoplasms, germ cell neoplasms, and tumors arising from adjacent structures, including meningiomas, astrocytomas, and ependymomas. Like other masses in this location, PTPR often leads to obstructive hydrocephalus. Due to the relative paucity of reported cases of PTPR, its natural history is unknown.

Dementia caused by dural arteriovenous fistulas reversed following endovascular therapy

We describe two patients who presented with dementia as the primary neurological manifestation of their dural arteriovenous fistula (dAVF). Although dementia is not the most common presentation for a dAVF, these cases show that obliterating the fistula can eliminate this dreadful manifestation. This awareness may facilitate the diagnosis of dementia in cases caused by dAVF and allow for a minimally invasive treatment that restores cognitive function back to baseline.

Vascular anatomic variation in rabbits.

PURPOSE To explore the vascular anatomic variation along the aortic arch in New Zealand White rabbits with the goal of highlighting potential anatomic configurations that might be encountered in the performance of preclinical endovascular research in rabbits. MATERIALS AND METHODS Digital subtraction angiography images of the brachiocephalic artery (BCA) and aortic arch in New Zealand White rabbits were obtained after creation of elastase-induced aneurysms at the origin of the right common carotid artery (RCCA) in 214 animals. The patterns of origin of the RCCA and left common carotid artery (LCCA), right subclavian artery (RSCA) and left subclavian artery (LSCA), and right vertebral artery (RVA) and left vertebral artery (LVA) were analyzed. RESULTS Five predominant variations of vessel origin were identified. In 200 of 214 cases (93%), the LCCA originated from the bifurcation of the BCA and aorta. In eight cases (4%), the LCCA directly originated from the aorta. In two cases (1%), the LCCA originated from the BCA. Aberrant RSCA anatomy in which the RSCA originated from the aortic arch instead of the BCA was found in three cases (1.5%). In a single case (0.5%), aberrant RSCA anatomy with the RVA originating from the BCA was encountered. CONCLUSIONS Anatomic variation of the BCA in New Zealand White rabbits is similar to that seen in humans. Understanding of the normal and variant anatomy of the rabbit will aid investigators who use the rabbit model for endovascular research.