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.
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.
Kenan AlKhalili, Nohra Chalouhi, Stavropoula Tjoumakaris, Robert Rosenwasser and Pascal Jabbour
Stereotactic radiosurgery is an effective management strategy for properly selected patients with arteriovenous malformations (AVMs). However, the risk of postradiosurgical radiation-related injury is higher in patients with large AVMs. Multistaged volumetric management of large AVMs was undertaken to limit the radiation exposure to the surrounding normal brain. This strategy offers a promising method for obtaining high AVM obliteration rates with minimal normal tissue damage. The use of embolization as an adjunctive method in the treatment of large AVMs remains controversial. Unfortunately, staged-volume radiosurgery (SVR) has a number of potential pitfalls that affect the outcome. The aim of this article is to highlight the role of SVR in the treatment of large AVMs, to discuss the outcome comparing it to other treatment modalities, and to discuss the potential improvement that could be introduced to this method of treatment.
Christopher J. Koebbe, Kenneth Liebman, Erol Veznedaroglu and Robert Rosenwasser
The use of endovascular management for recurrent carotid artery (CA) stenosis is rapidly expanding due to the increased surgical risk associated with repeated carotid endarterectomy (CEA). Carotid artery angioplasty and stent placement for recurrent CA stenosis offers a less invasive strategy with fewer procedural complications and may provide a more durable treatment. The authors report on their experience with this procedure in the management of recurrent CA stenosis.
A retrospective review was performed to evaluate clinical and ultrasound imaging outcomes after CA angioplasty and stent placement. Twenty-three vessels in 22 patients with severe recurrent stenosis (> 80%) post-CEA were treated with balloon angioplasty and stent placement without distal protection. There were no perioperative neurological or cardiac complications in this series. Over a mean follow-up period of 36 months, one patient (5%) suffered recurrent stenosis requiring retreatment with angioplasty alone.
The use of CA angioplasty and stent placement provides a safe and effective treatment for recurrent CA stenosis. The use of drug-eluting and/or bioactive stents in the future will likely further improve the efficacy of this procedure for recurrent CA stenosis.
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.
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.
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.
Badih Daou, Petra Klinge, Stavropoula Tjoumakaris, Robert H. Rosenwasser and Pascal Jabbour
There are several etiologies that can lead to the development of secondary normal pressure hydrocephalus (sNPH). The aim of this study was to evaluate the etiology, diagnosis, treatment, and outcome in patients with sNPH and to highlight important differences between the separate etiologies.
A comprehensive review of the literature was performed to identify studies conducted between 1965 and 2015 that included data regarding the etiology, treatment, diagnosis, and outcome in patients with sNPH. Sixty-four studies with a total of 1309 patients were included. The inclusion criteria of this study were articles that were written in English, included more than 2 patients with the diagnosis of sNPH, and contained data regarding the etiology, diagnosis, treatment, or outcome of NPH. The most common assessment of clinical improvement was based on the Stein and Langfitt grading scale or equivalent improvement on other alternative ordinal grading scales.
The main etiologies of sNPH were subarachnoid hemorrhage (SAH) in 46.5%, head trauma in 29%, intracranial malignancies in 6.2%, meningoencephalitis in 5%, and cerebrovascular disease in 4.5% of patients. In 71.9% of patients the sNPH was treated with ventriculoperitoneal shunt placement, and 24.4% had placement of a ventriculoatrial shunt. Clinical improvement after shunt placement was reported in 74.4% and excellent clinical improvement in 58% of patients with sNPH. The mean follow-up period after shunt placement was 13 months. Improvement was seen in 84.2% of patients with SAH, 83% of patients with head trauma, 86.4% of patients with brain tumors, 75% of patients with meningoencephalitis, and 64.7% of patients with NPH secondary to stroke.
Secondary NPH encompasses a diverse group of clinical manifestations associated with a subset of patients with acquired hydrocephalus. The most common etiologies of sNPH include SAH and traumatic brain injury. Secondary NPH does indeed exist, and should be differentiated from idiopathic NPH based on outcome and on clinical, pathophysiological, and epidemiological characteristics, but should not be considered as a separate entity.
Pascal Jabbour, Christopher Koebbe, Erol Veznedaroglu, Ronald P. Benitez and Robert Rosenwasser
The treatment of wide-necked cerebral aneurysms represents a challenging problem for neurosurgeons. The recent development of stents has provided clinicians with the ability to treat these aneurysms while keeping the parent vessel patent. The long-term occlusion rate of aneurysms treated with stent-assisted coil placement has yet to be investigated. The authors report the use of a new intracranial stent—the Neuroform microstent—in the treatment of unruptured wide-necked cerebral aneurysms.
Thirty-two patients harboring unruptured wide-necked intracranial aneurysms underwent a stent-assisted coil placement procedure. Patients were pretreated with antiplatelet agents, and a stent was positioned across the neck of the aneurysm. The next step was the insertion of coils into the aneurysm cavity. Patients received anticoagulation therapy for 24 hours after the procedure.
All 32 patients with unruptured wide-necked cerebral aneurysms were suitable candidates for this procedure. Occlusion of at least 90% of the aneurysm was achieved in 24 patients (75%) and 0% occlusion was observed in five patients (15%). Two patients experienced thromboembolic events, one of which was directly related to the stent. The overall complication rate was 6.3%.
Intracranial stents will be used more frequently in the new era of endovascular management of wide-necked cerebral aneurysms. With some technical improvements and more data on long-term occlusion rates, this new modality should improve the occlusion of wide-necked cerebral aneurysms while protecting the parent vessel.