The vascular plug: a new device for parent artery occlusion.

Parent artery occlusion (PAO) is still indicated at times for the treatment of craniocervical vascular disease. Because of the unavailability of silicone and latex balloons in the United States, costly combinations of detachable and pushable coils have been required to achieve PAO. We describe our experience with a simple and less expensive alternative for PAO in 4 carotid arteries and 1 vertebral artery. This device is limited to occlusions below the base of the skull.

Balloon-assisted coiling through a single 6F guiding catheter.

The new version of the 6F Envoy guiding catheter, with its enlarged inner diameter of 0.070 inch, is capable of simultaneously accommodating both a 0.014-inch microcatheter and a balloon microcatheter for balloon-assisted coiling (BAC). We report our experience using this guiding catheter for access in BAC in 48 patients. The guiding catheter allowed for easy manipulations of 2 microcatheters, while providing sufficient quality of control angiograms during the procedure. In cases in which BAC is indicated, a larger guiding catheter (7F) or the commonly used bifemoral approach is no longer necessary, making the procedure technically simpler for the operator and less traumatic to the vessel wall.

Delayed stroke secondary to increasing mass effect after endovascular treatment of a giant aneurysm by parent vessel occlusion.

A 47-year-old woman, who had lost vision in her left eye because of a giant left supraclinoid internal carotid artery aneurysm, was referred for endovascular treatment. Parent-vessel occlusion was performed to obtain circulatory exclusion of the aneurysm. Eight days after treatment, she became hemiparetic and dysphasic. Repeat angiography showed compression of the left middle cerebral artery by the swelling giant aneurysm. Preventive measures should be taken to avert worsening of mass effect when giant aneurysms become thrombotic.

Carotid endarterectomy results in the early years of practice.

BACKGROUND: Newly qualified surgeons, as well as their referring physicians, are understandably anxious when dangerous surgery is contemplated. Carotid endarterectomy (CEA), which requires a low morbidity/mortality rate to be successful, is especially problematic in this realm. There is a paucity of literature indicating the results that can be expected when a less-experienced surgeon is asked to perform this procedure. As the volume of CEA surgery is expected to decrease in the future with improvements in endovascular techniques, there will be fewer highly experienced CEA surgeons around. METHODS: We studied the first consecutive, prospectively recorded 100 CEAs performed by each of two newly qualified surgeons (200 total) between January 1993 and May 1998. Standard technique was used and all cases were done under general anesthesia. The only difference in technique was the more liberal use of shunting and protamine by one individual. RESULTS: There were no significant differences in the patient demographics between the two surgeons. Seventy-five percent of the cases harbored symptomatic stenoses. An overall combined stroke/mortality rate of 5.5% was observed. The rate in those operated on for symptomatic stenosis (n = 150) was 6% while it was 4% for those with asymptomatic pathology. There were no significant differences in outcome between the two surgeons. The average stroke/mortality rate in the first 50 cases for each surgeon was 7%, as opposed to 4% for the second 50 cases. CONCLUSIONS: These data indicate that less-experienced individuals can perform this procedure with good results.

Intracranial arterial aneurysms associated with arteriovenous malformations: endovascular treatment.

PURPOSE: To evaluate the results of endovascular treatment of patients having both arteriovenous malformations and aneurysms. MATERIALS AND METHODS: Two hundred seventy consecutive patients underwent pretherapeutic selective and superselective angiography. In each patient, the following were recorded: demographic information; clinical symptoms; location of the arteriovenous malformation, including presence of aneurysms; therapeutic interventions and immediate anatomic results; and clinical and angiographic follow-up data. Every patient who had at least one angiographically confirmed arterial aneurysm at presentation was included in the study. RESULTS: Arterial aneurysms were found in 30 (11%) of 270 patients in the population with arteriovenous malformations. Fifteen (50%) of 30 patients with aneurysms had a hemorrhage at presentation. Only 66 (27.5%) of 240 patients without aneurysms had a hemorrhage at presentation. The coexistence of arteriovenous malformations and aneurysms correlated significantly with intracranial hemorrhage at presentation (P <.05). When an aneurysm was believed to be responsible for a hemorrhage and whenever possible, it was treated before the arteriovenous malformation was treated. Treatments were protective against hemorrhage or recurrence of hemorrhage in all cases. Five of 30 patients had neurologic deficits as a result of endovascular treatment of both aneurysms and arteriovenous malformations. CONCLUSION: Findings in this study highlight the importance of recognizing aneurysms in patients with arteriovenous malformations. A strategic focus on the circulatory exclusion of associated aneurysms, especially when such lesions have been responsible for a hemorrhagic episode, is recommended.

Endovascular treatment of distally located giant aneurysms.

OBJECTIVE: Because giant aneurysms (GAs) can be technically difficult to clip, the endovascular approach is becoming increasingly popular. Endovascular treatment of distally located GAs, which often requires parent vessel occlusion, is particularly challenging because limited pathways are available for collateral flow. We aimed to determine the outcomes of endovascular attempts to treat GAs downstream from the circle of Willis. METHODS: Between 1991 and 1998, 27 patients with 27 distally located very large aneurysms or GAs were evaluated for possible endovascular treatment. Ten underwent selective embolization and 9 were treated with primary parent vessel occlusion, with or without distal bypass. Eight patients could not be treated endovascularly. RESULTS: Selective embolization resulted in only one cure. Two patients died as a result of subarachnoid hemorrhage during the follow-up period. One coil-treated patient, who underwent subsequent spontaneous parent vessel occlusion, and all nine patients treated primarily with parent vessel occlusion were considered cured after their treatments. Only two patients treated with parent vessel occlusion experienced periprocedural ischemia, which did not result in a major deficit in either case. Of the eight patients who could not be treated endovascularly, one succumbed to surgery, four died while being treated conservatively, and three were lost to follow-up monitoring. CONCLUSION: Selective aneurysm embolization is usually not curative in these situations. For selected patients, however, endovascular parent vessel occlusion is usually safe and effective in preventing the progression of symptoms and bleeding.

What's new in the treatment of cerebrovascular disease?: an endovascular perspective.

Surgical therapy currently allows for the correction of many pathologic conditions affecting the vasculature of the central nervous system. Recent advances in technology have given the cerebrovascular specialist further options in the minimally invasive sphere. Endovascular techniques, complimentary to surgery in some conditions, are poised to replace conventional open surgery in others. A review of current interventional radiological procedures for the treatment and prevention of ischemic and hemorrhagic stroke are herewith presented.

Nocardia asteroides cerebral abscess in immunocompetent hosts: report of three cases and review of surgical recommendations.

BACKGROUND: Nocardia asteroides cerebral abscesses are rare intracranial lesions. They account for only 2% of brain abscesses. Existing literature takes the form of anecdotal reports, small case series, and retrospective studies. An optimal treatment approach has not been established. However, there is evidence that the size of the lesion and clinical and immune status of the patient are relevant to surgical decision making. METHODS: Three recent cases are presented and the existing literature is reviewed. RESULTS: The outcome in all three cases was satisfactory. Although the currently recommended neurosurgical management protocols were followed, one patient had a prolonged course, which may have been shortened had an earlier biopsy of the cerebral lesion been performed. CONCLUSIONS: The surgical approach to suspected Nocardia spp. cerebral abscesses has recently become less aggressive. A more aggressive approach than that currently preferred for suspected Nocardia spp. cerebral abscesses may be appropriate. Earlier biopsy of lesions to achieve specific identification and anti-microbial sensitivity profiles is suggested even in cases where an extracranial focus of infection is found. Delays in obtaining a biopsy may lead to non-specific or unhelpful results that may prolong the course in hospital and jeopardize the outcome.

Percutaneous transluminal angioplasty and stenting of the proximal vertebral artery for symptomatic stenosis.

BACKGROUND AND PURPOSE: Percutaneous transluminal angioplasty (PTA) for significant stenosis involving the origin of the vertebral artery is now a well established treatment for selected patients when posterior cerebral arterial circulation is compromised. Arterial spasm, dissection, and restenosis may occur in some instances, with subsequent hemodynamic compromise. To prevent these potential complications, we combined PTA of the vertebral artery with primary stenting, using coronary stents, in seven patients. We herein present our short- and intermediate-term results. METHODS: A total of seven lesions affecting the origin of the vertebral artery were treated by primary trans-stenotic coronary stent placement. All patients were symptomatic, fulfilling the general criteria for vertebral artery angioplasty. Patients were followed for up to 36 months after treatment. RESULTS: All seven lesions were successfully dilated. Residual stenosis was never greater than 20% in diameter. No perioperative complications occurred. Clinical follow-up showed immediate resolution or improvement of symptoms in all patients. One patient's condition deteriorated 15 months after stent placement because of atheromatous stenosis of the prevertebral segment in the ipsilateral subclavian artery. CONCLUSION: Stent placement to treat significant stenosis involving the origin of the vertebral artery is safe and effective for alleviating symptoms and improving blood flow to the posterior cerebral circulation. Coronary stent design seems to be particularly well suited to cover atherosclerotic lesions of the origin of the vertebral artery. The stent mesh probably prevents elastic recoil and early restenosis after PTA, as it does in coronary arteries.

The retrograde approach: a consideration for the endovascular treatment of aneurysms.

BACKGROUND AND PURPOSE: The traditional endovascular approach to a cerebral aneurysm is anterograde, with the embolization and balloon protection catheters introduced via the parent vessel. Unfortunately, this approach may be restrictive, because these catheters cannot always be navigated at an optimal angle into the arterial branch that needs balloon protection or the part of the aneurysm that needs coiling. The purpose of this study was to determine the efficacy of a retrograde approach. METHODS: Twelve patients, seven women and five men, 28 to 65 years old (mean age, 45 years), were treated via the retrograde approach between March 1998 and February 1999. Three patients were treated for acutely ruptured aneurysms following subarachnoid hemorrhage. The rest had asymptomatic, unruptured aneurysms. RESULTS: We were able to accomplish endovascular treatment in 10 cases. In the other two, the attempted retrograde route of access could not be achieved. The treatment afforded complete embolization in nine of the 10 patients. Symptomatic distal clot embolization occurred in one patient who had some residual, albeit improving, deficits at discharge. No other patients worsened with the treatment. There were two intraprocedural aneurysmal ruptures. None of the aneurysms restudied within 6 months (eight of 12) showed evidence of recanalization. CONCLUSION: Our results indicate that it is possible to safely and effectively access a cerebral aneurysm via a retrograde approach. We believe that the anatomic benefits afforded by this technique outweigh the potential risks associated with the catheterization of another major cerebral arterial feeder.

3D Rotational Angiography: Recent Experience in the Evaluation of Cerebral Aneurysms for Treatment.

SUMMARY: Three dimensional (3D) reconstruction techniques providing volume rendered 3D images from rotational angiography data now exist.We report the design and early experience with one such system. 237 aneurysms were studied. Information was obtained on the morphology of the aneurysm itself and the vascular architecture in and around the aneurysm. 218 (92%) aneurysms went on to have endovascular treatment. The 3D images provided valuable information on aneurysmal anatomy, including relationships with the parent and adjacent vessels. This technique allowed fast and safe decision-making regarding the feasibility of endovascular or surgical treatment and provided useful information for performing the chosen treatment.

Primary antiphospholipid syndrome with moyamoya-like vascular changes.

We describe a young girl with antiphospholipid syndrome (APS) and moyamoya-like cerebrovascular changes which reversed after anticoagulation. Although there was a risk of hemorrhage from collateral vessels, we speculate that this treatment may have prevented progression of the vascular abnormalities, while resolution of the thrombus resulted in improved cerebrovascular circulation.

Autoradiographic [3H]nimodipine distribution after experimental spinal cord injury in rats.

Because of its potential for augmentation of blood flow and protection of neurons after neurological insult, nimodipine has been investigated as a treatment of spinal cord injury (SCI). The results have been inconsistent, possibly because of poor delivery of nimodipine to the injured spinal cord. The following study was designed to determine the delivery of nimodipine to the injured spinal cord. It was also hoped that information about the temporal and spatial pattern of binding of nimodipine after SCI might further elucidate the relationship between calcium channel activation and injury. Fourteen female Wistar rats were divided into three groups: control (n = 3), 30 min post-SCI (n = 6); and 4 h post-SCI (n = 5). The injury was produced by acute clip compression for 1 min at T1. [3H]Nimodipine was administered 5 min after laminectomy in the control group, and at the above-specified times after injury in the SCI groups. The drug was then allowed to equilibrate for 30 min before the animals were killed. The spatial patterns and concentrations of [3H]nimodipine in various segments of the spinal cord were autoradiographically determined. The highest concentrations of [3H]nimodipine were at the injury site after SCI. Also, the mean [3H]nimodipine concentrations in all sites in each animal were higher in the injury groups than in the control group (p < 0.05). This study indicates that delivery of this agent to the injured cord is possible, and provides evidence of widespread Ca2+ channel activation in the first 4 h after injury.

Cell-mediated allergy to a cerebral aneurysm clip: case report.

BACKGROUND AND IMPORTANCE: Titanium aneurysm clips have superior imaging characteristics and have been supplanting their stainless steel counterparts. We report the case of a 36-year-old woman with a histologically demonstrated cell-mediated reaction to a cobalt alloy aneurysm clip. CLINICAL PRESENTATION: The patient underwent a craniotomy and clip placement for a ruptured cerebral aneurysm. Both the aneurysm clip and the wires used to fix the craniotomy were made of stainless steel (cobalt and nickel) alloys. Postoperatively, the patient was plagued by intense pruritus. INTERVENTION: Skin patch testing revealed a severe reaction to nickel and cobalt. Surgical removal of the aneurysm clip and wires resulted in the disappearance of the patient's symptoms. A histological analysis of the tissue adjacent to the clip and wires was consistent with Type IV delayed type hypersensitivity. CONCLUSION: Stainless steel surgical implants in the head can cause diffuse, severe pruritus in susceptible individuals. Although the role of the aneurysm clip, as opposed to the more superficial wires, in the genesis of the patient's symptoms is not certain, this case demonstrates that a cobalt alloy aneurysm clip can activate T cells and cause an immunological reaction in the central nervous system.

Stereotactic radiosurgery for acoustic neuroma: a Canadian perspective.

Stereotactically delivered radiation is now an accepted treatment for patients with acoustic neuroma. In some cases, patient preference may be the reason for its selection, while in others neurosurgeons may select it for patients who are elderly or have significant risk factors for conventional surgery. The majority of patients with acoustic neuroma treatment with stereotactic radiosurgery have been treated with the Gamma Knife, with follow ups of over 25 years in some instances. Other radiosurgery modalities utilizing the linear accelerator have been developed and appear promising, but there is no long-term follow up. Canada does not possess a Gamma Knife facility, and its government-funded hospital and medical insurance agencies have made it difficult for patients to obtain reimbursement for Gamma Knife treatments in other countries. We review the literature to date on the various forms of radiation treatment for acoustic neuroma and discuss the current issues facing physicians and patients in Canada who wish to obtain their treatment of choice.

Giant fusiform aneurysm of the middle cerebral artery: successful Hunterian ligation without distal bypass.

Giant fusiform aneurysm is a rare vascular lesion which presents difficult management issues. We describe one such aneurysm in a middle cerebral artery branch (M2) that presented with subarachnoid haemorrhage and was managed operatively. Clinical, radiological and pathological presentations, as well as the different treatment options for this type of aneurysm are discussed based on a literature review. A satisfactory results in an M2 giant fusiform aneurysm can be achieved with Hunterian ligation of the parent vessel even when a distal EC-IC bypass is not possible.

Localized tension pneumothorax in patients with adult respiratory distress syndrome.

Tension pneumothorax as a complication of ventilatory support may cause severe cardiac problems. The diagnosis may be difficult. Risk factors predisposing to the misdiagnosis of this condition include atypical location of the pneumothorax. Three patients with adult respiratory distress syndrome who had atypical, localized tension pneumothorax are described. Each had an ipsilateral functioning chest tube in place at the time. Placement of chest tubes into the localized pneumothoraces resulted in immediate improvement in hemodynamic status in two patients, but the third patient died before the chest tube could be placed. A diagnosis of tension pneumothorax should be considered in any patient on a ventilator whose hemodynamic status deteriorates in the presence of high airway pressures. In patients with adult respiratory distress syndrome the pneumothorax can remain localized because the heavy, noncompliant lungs cannot collapse enough for air to dissect diffusely through the pleural space; pleural adhesions may also contribute to this phenomenon.

Encephaloduroarteriosynangiosis (EDAS) for the treatment of childhood moyamoya disease.

Moyamoya disease is defined by the angiographic demonstration of stenosis or occlusion of the vessels of the anterior circulation at the base of the brain and the concomitant development of collateral blood supply. Untreated, the disease is often clinically progressive, resulting in significant neurologic sequelae. Encephaloduroarteriosynangiosis (EDAS), which involves the transposition of a segment of a scalp artery onto the surface of the brain, is a surgical treatment aimed at improving collateral blood flow. Six children underwent 8 EDAS procedures and were followed from 6 months to 9 years after surgery. No patient experienced further deterioration in neurologic status. Postoperative angiography demonstrated cerebral revascularization from the donor scalp artery on 3 of the 6 EDASs that were studied. The 2 patients who did not revascularize after EDAS demonstrated angiographic regression of their disease. The data suggest that EDAS is a safe procedure for the treatment of childhood moyamoya disease. Given the potential severity of the sequelae, early operative intervention is recommended in all children with this disease.

Effect of nimodipine or methylprednisolone on recovery from acute experimental spinal cord injury in rats.

The purpose of the present study was to examine the behavioral, electrophysiologic, and anatomic responses to nimodipine or methylprednisolone treatment of acute experimental spinal cord injury. Four groups of rats were injured at T1 by compressing the cord with a 52-g clip for 1 minute. The treatments were begun 15 minutes after injury, and the animals were observed thereafter for 8 weeks. Nimodipine 0.02 mg/kg/h intravenously (iv) for 8 hours with adjuvant albumen volume expansion, followed by 20 mg/kg nimodipine enterally three times per day for 7 days, produced a moderately better composite score comprising four endpoint parameters than the other treatments which consisted of nimodipine iv for 8 hours only, methylprednisolone 30 mg/kg iv bolus followed by 5.4 mg/kg/h iv for 8 hours, or control.