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Rocco A. Armonda, Jeffrey E. Thomas and Robert H. Rosenwasser

Endovascular surgical technology is in the early stages of evolution. A critical phase of this development has been microcatheter technology, which has permitted sufficiently precise intravascular navigation to safely engage the lumen of the aneurysm itself. Digital subtraction angiography, rapid filming techniques and image acquisition, and simultaneous multiplanar imaging capability are indispensable tools that are constantly being refined in the setting of ever-improving computer technology. The marriage of these different technologies has allowed effective endovascular treatment of difficult-to-access aneurysms in medically compromised patients for whom open microsurgery has inherently higher risks.

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Rocco A. Armonda, Jeffrey E. Thomas and Robert H. Rosenwasser

The authors present the unique experience of one neurovascular service under the direct supervision of the senior author, for which surgical, endovascular, and intensive care treatments were conducted in a select group of 32 patients with aneurysmal subarachnoid hemorrhage who had medically intractable symptomatic vasospasm.

A protocol of early and aggressive treatment was instituted using pentobarbital coma, cerebral angioplasty, and intracranial pressure (ICP) reduction. The patient population consisted of 25 women and seven men, whose ages ranged from 34 to 60 years (average 47 years). The patients' Hunt and Hess grades on presentation were as follows: Grade 0 (one); Grade I (three); Grade II (two); Grade III (nine); Grade IV (10); Grade V (seven). Microsurgical clipping alone was performed in 15 of 32 patients, endosaccular occlusion was performed in 17 of 20 patients, and two patients underwent combined treatment. Subsequent angioplasty was performed in 26 of 32 patients. Additionally, all 32 patients underwent treatment of increased ICP with ventriculostomy placement, removal of the bone flap (11), evacuation of associated intracranial hematoma (five), and decompressive obectomy (four).

Twenty-one patients survived and 11 died. Of the 21 survivors, seven have returned to work, live independently, and have no neurological deficits; eight require minimal assistance at home; four are in rehabilitation with moderate deficits at 3 months; and two remain in a persistent vegetative state.

In this group of aggressively treated patients who received pentobarbital cerebral protection, successful treatment of medically intractable cerebral vasospasm was related to time of treatment (< 2 hours), expeditious reduction of elevated ICP, and angioplasty.

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Edison P. Valle-Giler, Elias Atallah, Stavropoula Tjoumakaris, Robert H. Rosenwasser and Pascal Jabbour

The Pipeline embolization device (PED) has become a very important tool in the treatment of nonruptured cerebral aneurysms. However, a patient’s difficult anatomy or vascular stenosis may affect the device delivery. The purpose of this article was to describe an alternate technique for PED deployment when ipsilateral anatomy is not amenable for catheter navigation.

A 44-year-old woman with a symptomatic 6-mm right superior hypophyseal artery aneurysm and a known history of right internal carotid artery dissection presented for PED treatment of her aneurysm. An angiogram showed persistence of the arterial dissection with luminal stenosis after 6 months of dual antiplatelet treatment. The contralateral internal carotid artery was catheterized and the PED was deployed via a transcirculation approach, using the anterior communicating artery. Transcirculation deployment of a PED is a viable option when ipsilateral anatomy is difficult or contraindicated for this treatment.

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Robert H. Rosenwasser, Laurence I. Kleiner, Joseph P. Krzeminski and William A. Buchheit

✓ Direct therapeutic drainage and intracranial pressure monitoring from the posterior fossa has never been accepted in neurosurgical practice. Potential complications including cerebrospinal fluid leak, cranial nerve palsies, and brain-stem irritation have been a major deterrent. The authors placed a catheter for pressure monitoring in the posterior fossa of 20 patients in the course of posterior fossa surgery: 14 patients with acoustic schwannomas, four with posterior fossa meningiomas, one with cerebellar hemangioblastoma, and one with a solitary cerebellar metastatic lesion. A Richmond bolt was also placed in the frontal area.

Continuous monitoring of the supratentorial and infratentorial compartments was performed for 48 hours. During the first 12 hours the posterior fossa pressure was 50% greater than that of the supratentorial space in all patients (p < 0.01). Over the next 12 hours the supratentorial pressure was 10% to 15% higher than the posterior fossa pressures in all patients, and by 48 hours of monitoring the pressures had equilibrated. There was no mortality or morbidity referable to insertion of the posterior fossa catheter.

The conclusions drawn from this study are that: 1) direct monitoring and drainage of the posterior fossa is safe and effective; and 2) within the early postoperative period, the supratentorial pressures failed to reflect what is taking place within the posterior fossa. The implications and advantages of direct posterior fossa monitoring in the postoperative patient are discussed.

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Badih Daou, Christine Hammer, Nohra Chalouhi, Robert M. Starke, Pascal Jabbour, Robert H. Rosenwasser and Stavropoula Tjoumakaris


Dissection of the carotid and vertebral arteries can result in the development of aneurysmal dilations. These dissecting pseudoaneurysms can enlarge and cause symptoms. The objective of this study is to provide insight into the progression of dissecting pseudoaneurysms and the treatments required to manage them.


A review of the electronic medical records was conducted to detect patients with carotid and vertebral artery dissection. An imaging review was conducted to identify patients with dissecting pseudoaneurysms. One hundred twelve patients with 120 dissecting pseudoaneurysms were identified. Univariate and multivariate analyses were conducted to assess the factors associated with undergoing further interventions other than medical treatment, pseudoaneurysm enlargement, pseudoaneurysms resulting in ischemic and nonischemic symptoms, and clinical outcome.


Overall, 18.3% of pseudoaneurysms were intracranial and 81.7% were extracranial, and the average size was 7.3 mm. The mean follow-up time was 29.3 months; 3.3% of patients had a recurrent transient ischemic attack, no patients had a recurrent stroke, and 14.2% of patients had recurrence of nonischemic symptoms (headache, neck pain, Horner syndrome, or cranial nerve palsy). Follow-up imaging demonstrated that 13.8% of pseudoaneurysms had enlarged, 30.2% had healed, and 56% had remained stable. In total, 20.8% of patients had an intervention other than medical treatment. Interventions included stenting, coiling, flow diversion, and clipping. Predictors of intervention included increasing size, size > 10 mm, location in the C2 (petrous) segment of the internal carotid artery (ICA), younger age, hyperlipidemia, pseudoaneurysm enlargement, and any symptom development. Significant predictors of enlargement included smoking, history of trauma, C2 location, hyperlipidemia, and larger initial pseudoaneurysm size. Predictors of pseudoaneurysm resulting in recurrent ischemic and nonischemic symptoms included increasing size and location in the petrous segment of the ICA. Smoking was a predictor of unfavorable outcome.


Dissecting pseudoaneurysms have a benign course and most will not cause symptoms or enlarge on follow-up. Medical treatment can be a sufficient, initial treatment for dissecting pseudoaneurysms.

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L. Fernando Gonzalez, Nohra Chalouhi, Stavropoula Tjoumakaris, Pascal Jabbour, Aaron S. Dumont and Robert H. Rosenwasser


Multiple approaches have been used to treat carotid-cavernous fistulas (CCFs). The transvenous approach has become a popular and effective route. Onyx is a valuable tool in today's endovascular armamentarium. The authors describe the use of a balloon-assisted technique in the treatment of CCFs with Onyx and assess its feasibility, utility, and safety.


The authors searched their prospectively maintained database for CCFs embolized using Onyx with the assistance of a compliant balloon placed in the internal carotid artery (ICA).


Five patients were treated between July 2009 and July 2011 at the authors' institution. A balloon helped to identify the fistulous point, served as a buttress for coils, protected from inadvertent arterial embolizations, and prevented Onyx and coils from obscuring the ICA during the course of embolization. No balloon-related complications were noted in any of the 5 cases. All 5 fistulas were completely obliterated at the end of the procedure. Four patients had available clinical follow-ups, and all 4 showed reversal of nerve palsies.


Balloon-assisted Onyx embolization of CCFs offers a powerful combination that prevents inadvertent migration of the embolic material into the arterial system, facilitates visualization of the ICA, and serves as a buttress for coils deployed in the cavernous sinus through the fistulous point. Despite adding another layer of technical complexity, an intraarterial balloon can provide valuable assistance in the treatment of CCFs.

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Rafael Ortiz, Michael Stefanski, Robert Rosenwasser and Erol Veznedaroglu


Aneurysms treated by endovascular coil embolization have been associated with coil compaction, and the rate of recanalization has been reported to be as high as 40%. The authors report the first published evidence of a correlation between aneurysm recanalization correlated with a history of cigarette smoking.


The authors conducted a retrospective chart review of all cases involving patients admitted to their institution from January 1, 2003, to December 31, 2003, for treatment of a cerebral aneurysm. Cases in which patients were treated with coil embolization were reviewed for inclusion. Coil compaction was defined as change in the shape of the coil mass. Aneurysm recanalization was defined as an increase in inflow to the aneurysm in comparison with baseline. The incidence of coil compaction and the relationship with cigarette smoking history were compared in patients with and without recurrence.


A total of 110 patients qualified for inclusion. The odds ratio (OR) for aneurysm recanalization after endosaccular occlusion with respect to history of cigarette smoking was significant for the entire cohort (OR 4.53, 95% confidence interval [CI] 1.95–10.52) and especially for the female cohort (OR 3.72, 95% CI 1.45–9.54). The male cohort demonstrated a trend toward a direct correlation, but the sample size was not large enough for statistical significance (OR 7.50, 95% CI 1.02–55.00).


There was an increased risk of recanalization especially in patients with low-grade subarachnoid hemorrhage who had a history of cigarette smoking. These data suggest a correlation between cigarette smoking and aneurysm recurrence.

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Robert H. Rosenwasser

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Ronald P. Benitez, Rocco A. Armonda, James Harrop, Jeffrey E. Thomas and Robert H. Rosenwasser

Carotid endarterectomy for atherosclerotic occlusive disease has become the standard of care for the treatment of symptomatic and asymptomatic occlusive disease of the carotid bifurcation, based on the results of the North American Symptomatic Carotid Endarterectomy Trial, as well as the Asymptomatic Carotid Atherosclerosis Study. For surgical treatment to be of benefit, the perioperative complication rate for neurological events should be 6% or less in the symptomatic population and 3% or less in the asymptomatic group. The performance of carotid endarterectomy for recurrent stenosis and radiation-induced stenosis has reported neurological events ranging from 4 to 10%. It is in this particular population that carotid angioplasty and stent placement may play a role.

The authors performed a retrospective analysis of 11 patients who underwent carotid angioplasty and stent placement for recurrent or radiation-induced stenosis. One patient in whom endarterectomy was performed by the vascular surgery service had a critical stenosis distal to the endarterectomy site and awoke with a neurological deficit. This patient underwent reexploration and placement of a stent in the artery distal to the arteriotomy site.

The follow-up period ranged from 7 to 12 months. Patient age ranged from 65 to 77 years (mean 75 years). Five of eight patients underwent angioplasty and stent placement for recurrent atherosclerotic disease. Two patients had radiation-induced stenosis, and one patient had a stent placed intraoperatively. All patients, with the exception of the one who underwent intraoperative stent placement, had posttreatment stenoses of less than 15%. The surgical patient had a 30% residual stenosis distally. There were no intra- or postoperative transient ischemic attacks, major or minor strokes, or deaths.

Patients who have recurrent or radiation-induced stenosis are potential candidates for angioplasty and stent placement. Before this can be recommended as an alternative to surgical correction, a longer follow-up period is required.