Pipeline-assisted coiling versus pipeline in flow diversion treatment of intracranial aneurysms.

BACKGROUND AND PURPOSE: Flow-diversion therapy (FDT) for large and complex intracranial aneurysms is effective and considered superior to primary coil embolization. Data evaluating common treatment with both FDT and coiling continues to emerge, but information on outcomes remains scarce. This study aims to examine further the efficiency and outcomes correlated with joint FDT using pipeline embolization device (PED) and coiling compared to PED-alone in treating intracranial aneurysms. MATERIALS AND METHODS: Comparative review and analysis of aneurysm treatment with PED in 416 subjects were conducted. Joint modality, PED, and coiling were compared to PED-alone for aneurysm occlusion, recurrence, retreatment, thromboembolic or hemorrhagic events, and functional outcome using the modified Rankin Scale. Data on patient demographics, aneurysm characteristics, clinical and angiographic follow up, were also collected. Both univariate analysis and multivariate logistic regression modeling using mixed-effects were performed. RESULTS: Total of 437 aneurysms were treated using PED of which 74 were managed with both PED and coiling. Average patient-age was 56 years, the majority were men (85%), an average aneurysm size was 9 mm, and the majority were saccular aneurysms (84%). Larger aneurysm size was associated with a poor outcome in patients with unruptured aneurysms (OR = 1.06). Adjusted regression analyses revealed no differences between treatment groups in thromboembolic or hemorrhagic events, aneurysm occlusion rate, residual flow on follow up angiography, or functional outcome. CONCLUSIONS: Treatment of intracranial aneurysms with joint PED and coiling was safe with no increase in complications when compared to PED alone. Aneurysm occlusion rates and functional outcome with PED and coiling stays comparable to treatment with PED-alone.

Pipeline Embolization Device in the Treatment of Recurrent Previously Stented Cerebral Aneurysms.

BACKGROUND AND PURPOSE: The use of the Pipeline Embolization Device in the management of recurrent previously stented cerebral aneurysms is controversial. The aim of this study was to evaluate the efficacy and safety of the Pipeline Embolization Device in the treatment of recurrent, previously stented aneurysms. MATERIALS AND METHODS: Twenty-one patients with previously stented recurrent aneurysms who later underwent Pipeline Embolization Device placement (group 1) were retrospectively identified and compared with 63 patients who had treatment with the Pipeline Embolization Device with no prior stent placement (group 2). Occlusion at the latest follow-up angiogram, recurrence and retreatment rates, clinical outcome, complications, and morbidity and mortality observed after treatment with the Pipeline Embolization Device were analyzed. RESULTS: Patient characteristics were similar between the 2 groups. The mean time from stent placement to recurrence was 25 months. Pipeline Embolization Device treatment resulted in complete aneurysm occlusion in 55.6% of patients in group 1 versus 80.4% of patients in group 2 (P = .036). The retreatment rate in group 1 was 11.1% versus 7.1% in group 2 (P = .62). The rate of good clinical outcome at the latest follow-up in group 1 was 81% versus 93.2% in group 2 (P = .1). Complications were observed in 14.3% of patients in group 1 and 9.5% of patients in group 2 (P = .684). CONCLUSIONS: The use of the Pipeline Embolization Device in the management of previously stented aneurysms is less effective than the use of this device in nonstented aneurysms. Prior stent placement can worsen the safety and efficacy profile of this device.

Combining stereotactic angiography and 3D time-of-flight magnetic resonance angiography in treatment planning for arteriovenous malformation radiosurgery.

PURPOSE: This study was initiated to evaluate the advantages of using three-dimensional time-of-flight magnetic resonance angiography (3D TOF MRA), as an adjuvant to conventional stereotactic angiography, in obtaining three-dimensional information about an arteriovenous malformation (AVM) nidus and in optimizing radiosurgical treatment plans. METHODS AND MATERIALS: Following angiography, contrast-enhanced MRI and MRA studies were obtained in 22 consecutive patients undergoing Gamma Knife radiosurgery for AVM. A treatment plan was designed, based on the angiograms and modified as necessary, using the information provided by MRA. The quantitative analysis involved calculation of the ratio of the treated volume to the MRA nidus volume (the tissue volume ratio [TVR]) for the initial and final treatment plans. RESULTS: In 12 cases (55%), the initial treatment plans were modified after including the MRA information in the treatment planning process. The mean TVR for the angiogram-based plans was 1.63 (range 1.17-2.17). The mean coverage of the MRA nidus by the angiogram-based plans was 93% (range 73-99%). The mean MRA nidus volume was 2.4 cc (range 0. 6-5.3 cc). The MRA-based modifications resulted in increased conformity with the mean TVR of 1.46 (range 1.20-1.74). These modifications were caused by MRA revealing irregular nidi and/or vascular components superimposed on the angiographic projections of the nidi. In a number of cases, the information from MRA was essential in defining the nidus when the projections of the angiographic outlines showed different superior and/or inferior extent of the nidus. In two cases, MRA revealed irregular nidi, correlating well with the angiograms and showed that the angiographically acceptable plans undertreated 27% of the MRA nidus in one case and 18% of the nidus in the other case. In the remaining 10 cases (45%), both MRI and MRA failed to detect the nidus due to surgical clip artifacts and the presence of embolizing glue. CONCLUSIONS: The 3D TOF MRA provided information on irregular AVM shape, which was not visualized by angiography alone, and it was superior to MRI for defining the AVM nidus. However, when imaging artifacts obscured the AVM nidus on MRI and MRA, angiography permitted detection of AVM. Utilizing MRA as a complementary imaging modality to angiography increased accuracy of the AVM radiosurgery and allowed for optimal dose planning.

Frequency of cerebral vasospasm in patients treated with endovascular occlusion of intracranial aneurysms.

UNLABELLED: The purpose of this study was to retrospectively compare a group of 19 patients treated with craniotomy and aneurysmal clipping with a group of 18 patients who were treated via endovascular occlusion with Guglielmi detachable coils in regard to frequency and severity of cerebral vasospasm. METHODS: All patients were treated within 48 hours of ictus. In the endovascular group, nine patients had Hunt and Hess grade I subarachnoid hemorrhage, five patients had grade II aneurysms, and four patients had grade III. According to the Fisher classification, one aneurysm was grade I, nine were grade II, and eight were grade III. Twelve of the aneurysms were on the anterior circulation and seven were on the posterior circulation. In the surgical group, 10 patients had Hunt and Hess grade I hemorrhage, seven had grade II aneurysms, and two had grade III. Nine of these were Fisher grade II and 10 were grade III. Eighteen aneurysms were on the anterior circulation and one was on the posterior circulation. Endovascularly treated patients were medically treated identically to those in the surgical group, with prophylactic volume expansion and hemodilution immediately after endovascular occlusion, except that they also received 48 hours of full heparinization followed by 24 hours of dextran infusion after endovascular occlusion. RESULTS: All four patients in the endovascular group in whom delayed neurologic deficits developed as a result of vasospasm responded to elevation of blood pressure and did not require either mechanical or chemical angioplasty to reverse their symptomatology. In the surgical group, 14 of 19 developed clinical vasospasm, with elevation of their transcranial Doppler velocities, and required maximum triple-H (hypertensive, hypervolemic, hemodilutional) therapy. Three of these patients required mechanical and pharmacologic angioplasty. No surgical complications were incurred as a direct result of the craniotomy. One patient in the endovascular group developed a femoral pseudoaneurysm as a complication of the procedure and postocclusion anticoagulation. No thromboembolic events were noted in this group. CONCLUSION: In patients with similar Hunt and Hess grades and Fisher grades, preliminary data suggest that the frequency and severity of cerebral vasospasm may be reduced in those treated by endovascular occlusion of their aneurysm as compared with those treated by direct surgical clipping.

Leukocyte involvement in cerebral infarct generation after ischemia and reperfusion.

White blood cell involvement in the generation of cerebral infarcts was evaluated following ischemia and reperfusion injury in the rat. Control and leukopenic rats (induced by vinblastine, WBC counts < 1500/mm3) were compared in a global forebrain ischemic model after 1 h of ischemia and 1 h 15 min of reperfusion. Cerebral infarcts were defined on coronal brain sections using Triphenyl tetrazolium chloride (TTC) staining. Electroencephalographic activity (EEG) and somatosensory evoked potentials (SSEP) were also compared. Results indicate that the area infarcted in leukopenic rats was significantly less than infarcts generated in corresponding controls (21 +/- 16% vs. 70 +/- 16%). In addition, EEG was preserved in all leukopenic animals when compared to controls, both during ischemia and after reperfusion. The cortical peak component of the SSEP was also better preserved in the leukopenic animals both during ischemia and at 60 min of reperfusion. These results indicate white blood cell participation in the generation of cerebral damage in a model of global forebrain ischemia and reperfusion as indicated by TTC staining of cerebral infarcts.

Complement depletion improves neurological function in cerebral ischemia.

The contribution of the complement system to the exacerbation of cerebral ischemia/reperfusion injury was studied by comparing a group of rats with normal complement levels to another group that was complement depleted by cobra venom factor (CVF). The magnitude of reactive hyperemia was significantly greater in the complement depleted animals. There was also better preservation of somatosensory evoked potentials (SSEPs) in the complement depleted animals. These differences were not associated with changes in leukocyte infiltration as evidenced by myeloperoxidase and Leukotriene B4 activity. These data demonstrate that depleting the complement system can improve flow and outcome following cerebral ischemia with reperfusion.

Experience with the suction-irrigation technique in the management of spinal epidural infection.

Nine patients with spinal epidural infection were managed with the suction-irrigation technique with excellent healing of the incision by primary intention in every case. The patients have been followed for 3 to 40 months. One patient developed a subcutaneous stitch abscess, which was treated by removal of the suture material. The surgical technique is described.

Reversal of severe cerebral vasospasm in three patients after aneurysmal subarachnoid hemorrhage: initial observations regarding the use of intraventricular sodium nitroprusside in humans.

OBJECTIVE AND IMPORTANCE: The chronic delayed type of cerebral vasoconstriction that occurs after aneurysmal subarachnoid hemorrhage (SAH) is now the most important cause of mortality and neurological morbidity for patients who initially survive the rupture of cerebral aneurysms. Although intravascular volume expansion and cardiac performance enhancement have had a profound impact on the treatment of the chronic delayed type of cerebral vasoconstriction, this form of treatment is not tolerated by all patients and is unhelpful in some. A more specific and more reliable treatment for this condition has not been previously reported. Previous work in an animal model has demonstrated the efficacy of nitric oxide-donating compounds in reversing severe cerebral vasoconstriction when delivered to the adventitial side of the blood vessel. A clinical study was initiated after receiving approval from the United States Food and Drug Administration and the institutional review board. CLINICAL PRESENTATION: Three cases of prompt and substantial reversal of medically refractory vasospasm occurring after aneurysmal SAH in humans using an intrathecally administered nitric oxide donor and clinical, angiographic, and ultrasonographic documentation are presented. All patients developed severe vasospasm refractory to medical treatment 5 to 12 days after sustaining aneurysmal SAH. All patients manifested stupor of new onset (Glasgow Coma Scale score of 7) and new focal neurological deficit (hemiplegia). The condition was angiographically demonstrated in all cases. INTERVENTION: The patients were treated with intrathecally administered sodium nitroprusside, which caused the reversal of vasospasm, which was documented by angiography and transcranial Doppler ultrasonography up to 54 hours later and also by dramatic clinical improvement. Complications related to intracranial pressure elevation, changes in vital signs, and hemodynamic parameters were not observed during or after the procedures. Radiographic evidence of the reversal of vasospasm and brain ischemia was obtained. The clinical outcomes of the treated patients were excellent. All patients presented with hemiplegia and stupor that resolved or markedly improved (within several days, two patients; within 12 hours, one patient). All three patients were discharged and were living at home at the time of manuscript submission. CONCLUSION: These preliminary observations suggest that sodium nitroprusside delivered by an intrathecal route of administration may be a useful treatment for severe vasospasm complicating SAH in humans.

Electroencephalographic activity and serum and cerebrospinal fluid pentobarbital levels in determining the therapeutic end point during barbiturate coma.

Controversy exists regarding the optimal means for monitoring the patient receiving pentobarbital therapy during medical coma. Serum pentobarbital levels have been used traditionally to gauge cerebral penetration and efficacy of the drug. These peripheral levels have been assumed to reflect pentobarbital concentrations in the cerebrospinal fluid (CSF) and, therefore, the physiological effect on the central nervous system. To determine the relative accuracy of serum versus CSF pentobarbital levels, continuous electroencephalographic (EEG) monitoring in 10 consecutive patients was studied prospectively. Each patient received pentobarbital therapy for cerebral protection in the face of a traumatic injury. Simultaneous serum and CSF pentobarbital levels were obtained 1) before and after the initial barbiturate bolus, 2) every 12 hours during constant infusion therapy, and 3) before and after subsequent boluses necessary because of elevated intracranial pressure (ICP) (ICP greater than 15 mm Hg) or loss of burst suppression by continuous EEG monitoring (defined as greater than five bursts per minute). ICP and relevant clinical events were recorded hourly. Serum and CSF levels ranged from 33 to 74 mg/L and 4 to 54 mg/L, respectively. There was poor correlation between serum and CSF pentobarbital levels at any given time, although patients remained in burst suppression 73% of the time during their therapy. The EEG monitoring not only provided dynamic physiological monitoring, but it also permitted the lowest pentobarbital dose to maintain burst suppression for a specific patient's metabolism, reducing the likelihood of toxicity. In conclusion, CSF pentobarbital levels are of no greater accuracy than serum pentobarbital levels in predicting physiological effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Temporary motor and sensory paralysis associated with intrathecal administration of morphine.

We are reporting a temporary, totally reversed motor and sensory paralysis subsequent to the intrathecal administration of 1.6 mg of morphine sulfate. This may represent an event which is not based on medication-induced myelopathy but on cardiovascular changes occurring as a result of pain relief.

Diagnosis and management of occipital condyle fractures.

The authors recently treated three cases involving fractures of the occipital condyle. First described by Bell in 1817, this lesion has proven to be very rare, with only 32 cases previously reported in the literature. Plain films often do not reveal any abnormality, making diagnosis difficult. High-resolution computed tomography has been demonstrated to be very sensitive in diagnosing this lesion. This fact was borne out in the authors' series. All of the authors' patients were managed either with a Philadelphia collar or with halo fixation, with excellent outcomes.

High dose fentanyl-oxygen anesthesia for intracranial mycotic aneurysm surgery: a clinical report.

The resection of a mycotic aneurysm in a patient with concurrent cardiac valvular disease was carried out successfully using high dose fentanyl-oxygen anesthesia followed by immediate postoperative naloxone reversal. The technique and benefits of this type of anesthesia in neurosurgical procedures are discussed.

Complications of Swan-Ganz catheterization for hemodynamic monitoring in patients with subarachnoid hemorrhage.

Invasive hemodynamic monitoring has become standard in the management of aneurysmal subarachnoid hemorrhage. This study is a retrospective analysis of 630 Swan-Ganz catheters placed in 184 patients with aneurysmal subarachnoid hemorrhage. Evaluation of complications demonstrated a 13% incidence of catheter-related sepsis (81 of 630 catheters), a 2% incidence of congestive heart failure (13 of 630 catheters), a 1.3% incidence of subclavian vein thrombosis (8 of 630 catheters), a 1% incidence of pneumothorax (6 of 630 catheters), and a 0% incidence of pulmonary artery rupture. In the management of patients with aneurysmal subarachnoid hemorrhage, invasive hemodynamic monitoring continues to be an important tool with acceptable complications.

Facial reanimation after facial nerve injury.

Patients with facial paralysis are often seen in neurosurgical practice. Obtaining full facial symmetry and function after facial nerve damage presents the neurosurgeon with a difficult challenge. Various surgical techniques have been developed to deal with this problem. These include primary nerve repair, nerve to nerve anastomosis, nerve grafting, neurovascular pedicle grafts, regional muscle transposition, microvascular muscle transfers, and nerve transfers. Patient selection, timing of surgery, and details of surgical technique are discussed. The results of hypoglossal-facial anastomosis in 24 patients are described.

Control of hypertension and prophylaxis against vasospasm in cases of subarachnoid hemorrhage: a preliminary report.

Thirty hypertensive patients with subarachnoid hemorrhage were divided randomly into two groups. The treated group was begun on preliminary volume expansion, and control of hypertension was carried out using vasodilators and centrally acting drugs. The control group was treated in the classical manner for hypertension, with a diuretic as the foundation for therapy. The incidence of clinical vasospasm was compared to that of angiographic spasm. The incidence of preoperative vasospasm in the treated group was 20%, as compared to 60% in the untreated group (P less than 0.01). Of the treated group, 87% survived to operation, whereas only 53% of the control group survived to operation (P less than 0.01).

Prevention of carotid angioplasty-induced bradycardia and hypotension with temporary venous pacemakers.

OBJECTIVE: Carotid angioplasty with stent placement is becoming an established treatment modality for patients with high-risk carotid stenosis. Unlike carotid endarterectomy, angioplasty causes direct mechanical dilation of the stenotic carotid artery and bulb. Stimulation of the sinus baroreceptors induces a reflexive response that consists of increased parasympathetic discharge and inhibition of sympathetic tone, which results in bradycardia and subsequent cardiogenic hypotension. METHODS: At a single institution, the experience with 43 patients treated from November 1994 to January 2000 with 47 angioplasty and stent procedures for occlusive carotid artery disease was retrospectively reviewed. Prophylactic temporary venous pacemakers were used to prevent hypotension from possible angioplasty-induced bradycardia. Pacemakers were set to capture a heart rate decrease below 60 beats per minute. Variables analyzed included demographics, etiology of disease, side of the lesion, the presence of symptoms, history of coronary artery disease, percent stenosis, type of stent used, number of dilations, pressure of dilation, and angioplasty balloon diameter. RESULTS: Ten patients were excluded because pacemakers were not used during their angioplasty procedures, and these included three emergencies and a lesion that was unrelated anatomically to the carotid sinus (petrous carotid). The remaining 37 procedures were performed in 33 patients with a mean age of 67 years, and consisted of 17 men, 16 women, 20 right and 17 left-sided lesions. The pacemakers maintained a cardiac rhythm in 23 (62%) of the 37 procedures and in no case did the pacemaker fail to respond when activated. Recurrent (56%; 10 of 18), radiation-induced (78%; 7 of 9), and medically refractory carotid stenosis (67%; 6 of 9) required intraprocedural pacing. Two patients with recurrent stenosis became hypotensive despite the aid of the pacing device but were not symptomatic. Seventy-nine percent (15 of 19) of symptomatic lesions and 57% (8 of 14) of nonsymptomatic lesions required pacing, which was statistically significant (P = 0.049). No patient experienced an operative morbidity or mortality as a consequence of the temporary pacing devices. CONCLUSION: Angioplasty-induced bradycardia is a common condition, and it is more prevalent in radiation-induced stenosis and with symptomatic lesions. Temporary venous demand pacing is a safe procedure and may prevent life-threatening, baroreceptor-induced hypotension.

A review of size and location of ruptured intracranial aneurysms.

OBJECTIVE: To review our experience and examine the size at which aneurysms ruptured in our patient population. METHODS: Patient charts and angiograms for all patients admitted with a diagnosis of subarachnoid hemorrhage to the Thomas Jefferson/Wills Eye Hospital between April 1996 and March 2000 were reviewed. RESULTS: Of the 362 cases reviewed, definite measurements of the ruptured aneurysm were obtained in 245. The data clearly showed that most ruptured aneurysms presenting to our institution were less than 10 mm in diameter. We found that, regardless of location on the circle of Willis, 85.6% of all aneurysms presenting with rupture were less than 10 mm. Review by location shows that aneurysms of the anterior communicating artery most often presented with rupture at sizes less than 10 mm (94.4%). A large number of ruptured posterior communicating artery aneurysms also presented at sizes less than 10 mm (87.5%). This trend continued for all aneurysm sites in our review. The incidence of subarachnoid hemorrhage in Western countries is estimated at 10 per 100,000 people per year. Recent reports have indicated that aneurysms less than 10 mm in size are unlikely to rupture. CONCLUSION: We argue that the risk of small aneurysms rupturing is not insignificant, especially those of the anterior communicating artery. Our findings indicate that surgery on unruptured aneurysms should not be predicated on aneurysm size alone.

Assessment of acutely unsuccessful attempts at detachable coiling in intracranial aneurysms.

OBJECTIVE: Guglielmi detachable coiling (GDC) has quickly become the most common endovascular method for the treatment of intracranial aneurysms. Although several published case series describe various authors' successful experiences or complications, few have elaborated on failed attempts. We examined our experience with GDC, and we analyzed all failed attempts at coiling. METHODS: Patients who underwent endovascular procedures from September 1995 through July 1999 were identified using endovascular case logs and billing records. Patient charts were then reviewed retrospectively for failed attempts at GDC. A treatment failure was defined as an inability to place coils into an aneurysm, a GDC procedure-related complication resulting in death, or an acute rehemorrhage from a coiled aneurysm that indicated a failure of coils to prevent rerupture. Thromboembolic events and other nonfatal sources of morbidity that did not preclude coiling of the aneurysm were analyzed only to the extent that they prevented successful coiling of the aneurysm. RESULTS: From September 1995 to June 1999, 241 patients underwent GDC embolizations or attempts. In these patients, 35 procedures were unsuccessful, including 7 deaths from intraoperative or postoperative aneurysmal rerupture. Sixteen aneurysms could not be microcatheterized, nine of which were anterior communicating artery aneurysms. Coils from 13 wide-necked aneurysms (average fundus-to-neck ratio, <2) prolapsed into the parent vessel. Three procedures were abandoned when the aneurysms were found to have normal branches filling from the dome, and three additional procedures were abandoned for technical reasons. Five deaths resulted from intraoperative aneurysm rupture, and two patients died postoperatively from rerupture. CONCLUSION: The number of successful coiling procedures has increased with experience and improved technology. The procedure still involves risks, however, primarily for patients with subarachnoid hemorrhage.

Therapeutic modalities for the management of cerebral vasospasm: timing of endovascular options.

OBJECTIVES: To determine if a window of time could be defined during which angioplasty would be most effective in reversing neurological decline and ultimately improving outcome. METHODS: Of a group of 466 patients, 93 underwent endovascular management of clinical vasospasm that was medically refractory. Eighty-four of the 93 patients were available for follow-up for at least 6 months. All patients underwent mechanical angioplasty using compliant microballoon systems and, if distal spasm was present, the administration of papaverine. RESULTS: Fifty-one patients underwent endovascular management within a 2-hour window, and 33 patients underwent treatment more than 2 hours after the development of their symptoms. Compared with the group treated more than 2 hours after neurological decline (P < 0.01; chi2 = 8.02), the group that underwent endovascular management within a 2-hour window after the development of symptoms demonstrated sustained clinical improvement. CONCLUSION: When a patient develops symptomatic vasospasm and is unresponsive to traditional measures of critical care management, angioplasty may be effective in improving the patient's neurological status if this procedure is performed as early as possible. The results indicate that a 2-hour window may exist for restoration of blood flow to ultimately improve the patient's outcome.

Temporal changes in sensitivity of rats to cerebral ischemic insult.

OBJECT: Experimental rat models are often used to study cerebral ischemia, yet rats are nocturnal animals that have activity cycles that are the opposite of those of humans. In the following study the authors examined the circadian rhythm of sensitivity to an ischemic insult in rats by using an intraluminal thread technique to produce reversible middle cerebral artery occlusion. METHODS: Ischemia (2 hours of blockage followed by 22 hours of reperfusion) was induced in rats according to the 24-hour clock at either 100, 400, 700, 1,000, 1,300, 1,600, 1,900, or 2,200 hours (11-14 rats per time period). The rat brains were removed, coronally sectioned, stained with 2,3,5-triphenyltetrazolium chloride and analyzed using commercially available software. Analysis of variance and cosinor-rhythmometry statistical tests were used for analysis of data. The time of day when the ischemic infarct was induced had a significant (p = 0.011) influence on the volume of the lesion. The volume of total brain infarct produced at 400 hours (7.65 +/- 1.31%) was more than three times greater than the volume produced at 1600 hours (2.1 +/- 0.34%). Cosinor-rhythm analysis indicated a peak occurrence of infarct volume at 6:02 (95% confidence interval 5:49-6:16). The size of the infarct correlated with core body temperature rhythms, which varied by 1.3 +/- 0.62 degrees C (mean +/- standard deviation). CONCLUSIONS: Circadian rhythms, as well as the reversed natural body rhythms of the rat compared with humans, should be considered when extrapolating data to human or other animal studies. Temporal rhythms may also provide information concerning the cascading disease processes associated with cerebral ischemia.