Middle Cerebral Artery Bifurcation Aneurysms Treated by Extrasaccular Flow Diverters: Midterm Angiographic Evolution and Clinical Outcome.

BACKGROUND AND PURPOSE: Flow diverters have been increasingly used lately in off-label, distal intracranial aneurysm treatments. Our aim was to evaluate the effectiveness of flow diverters in the treatment of middle cerebral artery bifurcation aneurysms and to analyze midterm angiographic patterns of regional flow modifications for safety and clinical outcomes. MATERIALS AND METHODS: Consecutive patients treated from January 2010 to December 2014 by the authors by using endovascular flow-diverting stents for MCA bifurcation aneurysms were evaluated retrospectively with prospectively maintained data. All patients had been followed for at least 12 months after treatment, with at least 2 control angiograms; regional flow-related angiographic modifications were registered by using a new angiographic outcome scale for flow diverters. Data were analyzed with emphasis on procedure-related events, angiographic results, and clinical outcome. RESULTS: Fifty-eight patients were included in the study, with 63 MCA bifurcation aneurysms; 13 of these were large and giant. Pretreatment mRS was 0 for 12 patients (20.7%), 1 for 41 (70.7%), and 2 for 5 patients (8.6%). Six-month control revealed mRS 0-2 for 57 (98.3%) patients and 3 for 1 (1.7%) patient. Procedure-related morbidity and mortality were 8.6% (5/58) and 0%, respectively. From 95% of still circulating immediate postprocedure angiographic outcomes, 68% progressed to aneurysm occlusion at 6 months and 95%, to occlusion at 12 months, with a 0% aneurysm rupture rate. CONCLUSIONS: Flow diverters seem to be an effective treatment alternative for complex MCA bifurcation aneurysms, with reasonable complication rates. Longer angiographic follow-ups are needed to assess the morphologic outcome; immediate subtotal occlusions do not seem to be related to rupture.

A New Aneurysm Occlusion Classification after the Impact of Flow Modification.

A new classification is proposed for cerebral aneurysms treated with any endovascular technique, for example, coiling with or without adjunctive devices, flow diversion, intrasaccular flow modifiers, or any combination of the above. Raymond-Roy Occlusion Classification is expanded with novel subgroups such as class 1 represents complete occlusion and is subdivided if a branch is integrated to, or originated from, the aneurysm sac; class 2 represents neck filling; class 3 represents incomplete occlusion with aneurysm filling as in the previous classification; and class 4 describes the immediate postoperative status after extra- or intrasaccular flow modification treatment. A new concept, "stable remodeling," is included as class 5, which represents filling in the neck region that stays unchanged or reduced, as shown with at least 2 consecutive control angiographies, at least 6 months apart, for not <1 year, or the remodeled appearance of a dilated and/or tortuous vessel in continuation with the parent artery without sac filling.

Endovascular treatment of middle cerebral artery aneurysms with flow modification with the use of the pipeline embolization device.

BACKGROUND AND PURPOSE: The Pipeline Embolization Device was reported to be safe and effective in the treatment of sidewall aneurysms, preserving the patency of the vessels covered by the construct. However, to date, the safety and efficacy of this device in treating bifurcation aneurysms remains unknown. We report our preliminary experience with the use of the Pipeline Embolization Device in the management of MCA aneurysms located at the bifurcations, including mid- and long-term follow-up data. MATERIALS AND METHODS: Wide-neck MCA aneurysms, which give rise to a bifurcating or distal branch in which other endovascular techniques are thought to be unfeasible or more risky, were included. Data including demographics, aneurysm features, antiplatelet therapy, complications, and angiographic follow-up results for up to 30 months were recorded. RESULTS: Twenty-five aneurysms located at the MCA bifurcation (n = 21) or distal (n = 4) were treated. Of these, 22 were small and 3 were large. A single device was used in all but 2. No deaths occurred in the series. All patients had at least 1 control angiographic study, 21 of which were DSA (3-30 months), which showed that 12 of the rising branches were patent whereas 6 were filling in reduced caliber and 3 were occluded asymptomatically. According to the last angiographic follow-up, complete occlusion was revealed in 21 of 25 aneurysms (84%). CONCLUSIONS: The Pipeline Embolization Device provides a safe and effective treatment alternative for wide-neck MCA aneurysms that give rise to a bifurcating or distal branch when other endovascular techniques are thought to be unfeasible or more risky.

Stent-assisted coiling in endovascular treatment of 500 consecutive cerebral aneurysms with long-term follow-up.

BACKGROUND AND PURPOSE: Stent-assisted coil embolization has become one of the most preferred techniques in the treatment of wide-neck intracranial aneurysms; however, long-term patency and safety of the self-expanding neurostents and their role in durability of the endovascular treatment has remained ambiguous. We sought to retrospectively examine the long-term results of self-expanding stent usage in conjunction with coil embolization in treatment of wide-neck cerebral aneurysms. MATERIALS AND METHODS: We coiled 500 wide-neck cerebral aneurysms with different types of self-expanding neurostent assistance in 468 patients. Patient and aneurysm characteristics, pharmacologic therapy protocol, complications, and initial occlusion grades were analyzed. Patients underwent angiographic follow-up at 6 months to 7 years after treatment. DSA or MRA images of all patients were analyzed to assess the occlusion rate of aneurysms and patency of the parent artery. RESULTS: Enterprise (n = 340), Solitaire (n = 98), Wingspan (n = 41), LEO (n = 16), and Neuroform (n = 5) stent systems were used in this series. Stent-related thromboembolic events occurred in 21 patients and intraoperative rupture occurred in 4 patients. Initially, complete occlusion was achieved in 42.2% of the aneurysms, and, according to the last follow-up data, the rate had progressed to 90.8%. Recanalization rate at 6 months was 8%, whereas the late recanalization rate was 2%. CONCLUSIONS: The use of stents in endovascular treatment provides high rates of complete occlusion and low rates of recurrence at a long-term follow-up study.

Treatment of intracranial aneurysms using the pipeline flow-diverter embolization device: a single-center experience with long-term follow-up results.

BACKGROUND AND PURPOSE: Flow-diverting devices now offer a new treatment alternative for cerebral aneurysms. We present the results of a large single-center series of patients treated with the PED, including long-term follow-up. MATERIALS AND METHODS: Between November 2008 and September 2011, sidewall aneurysms with a wide neck (≥4 mm) or unfavorable dome-neck ratio (≤1.5); large/giant, fusiform, dissecting, blister-like, and recurrent sidewall aneurysms; aneurysms at difficult angles; and aneurysms in which a branch was originating directly from the sac were treated with the PED. Patients were premedicated with dual antiplatelet medications. Data, including demographics, aneurysm features, clinical presentation, complications, results, and follow-up information, for up to 2 years are presented. RESULTS: Two hundred fifty-one aneurysms in 191 patients were treated. Of these, 96 (38.3%) were large or giant (≥10 mm). In 34/251 (13.5%), PEDs were used for retreatment. Adjunctive coiling was performed in 11 aneurysms (2.1%). The mean number of devices per aneurysm was 1.3. One aneurysm ruptured in the fourth month posttreatment (0.5%), and symptomatic in-construct stenosis was detected in 1 patient (0.5%) treated with percutaneous transarterial angioplasty. Any event rate was 27/191 (14.1%), with a permanent morbidity of 1% and mortality of 0.5%. Control angiography was available in 182 (95.3%) patients with 239 (95.2%) aneurysms. In 121 aneurysms (48.2%), 1- to 2-year control angiography was available. The aneurysm occlusion rate was 91.2% in 6 months, increasing to 94.6%. CONCLUSIONS: Use of the PED is safe, efficacious, and durable in cerebral aneurysm treatment, with low morbidity-mortality and high occlusion rates as confirmed with mid- to long-term control angiography.

A novel "Y" stent flow diversion technique for the endovascular treatment of bifurcation aneurysms without endosaccular coiling.

BACKGROUND AND PURPOSE: Stent-assisted endovascular treatment and flow diversion techniques are increasingly used for the management of wide-neck intracranial aneurysms. We report our initial clinical experience using a new flow diversion technique for the endovascular management of bifurcation aneurysms. MATERIALS AND METHODS: Eight bifurcation aneurysms were treated by placing 2 stents in Y-configuration with no accompanying endosaccular packing. This treatment technique aimed at flow diversion was selected in these cases because 1) the aneurysm was giant and causing mass effect, 2) the emanating branches were incorporated within the sac, or 3) the aneurysm was too small. Aneurysms were located at middle cerebral (5 aneurysms) and basilar artery bifurcations (3 aneurysms). Five aneurysms were small, 1 was large, and 2 were partially thrombosed giant. Closed-cell stents were used in all Y-stent placement procedures. RESULTS: In all aneurysms, both stents could be placed at the intended locations without any procedural complication. Follow-up angiograms obtained at 3 months to 2 years demonstrated that all stents were patent except for one with asymptomatic P1 occlusion. Complete occlusion with remodelled bifurcation was observed in all middle cerebral artery bifurcation aneurysms and the large basilar tip aneurysm. Residual filling despite reduction in size was observed in both of the partially thrombosed giant aneurysms at 2-year and 3-month follow-up angiograms, respectively. CONCLUSIONS: Flow diversion with double stent placement in Y-configuration provided successful and stable aneurysm occlusion. The technical and clinical results achieved are highly encouraging that this technique may contribute to the endovascular treatment of these complex bifurcation aneurysms.

Focal increased cortical density in immediate postembolization CT scans of patients with intracranial aneurysms.

BACKGROUND AND PURPOSE: Cortical hyperdensity was observed in the immediate postembolization CT scans of some patients with intracranial aneurysms following uneventful endovascular treatments. The clinical significance and possible underlying mechanism were evaluated. MATERIAL AND METHODS: Ninety-three consecutive patients with a total of 100 intracranial aneurysms, treated by endosaccular packing, were studied. Seventy-four aneurysms were treated with balloon assistance, and the remaining aneurysms were treated without balloon assistance. All patients underwent cranial CT just before and immediately after the endovascular treatment. If the post-treatment CT showed any new finding, an immediate MR imaging and a repeat CT 4-6 hours after the initial posttreatment CT were performed. Several parameters were investigated related to the presence of cortical hyperdensity. RESULTS: Cranial CT showed focal cortical hyperdensity following the treatment of 40/74 aneurysms (54%) with balloon remodeling and 9/26 aneurysms (34.6%) without balloon assistance. None of these patients were symptomatic, and cortical hyperdensity resolved in the repeat CT scans. A statistically significant relationship was observed between the presence of this finding and the total amount of contrast material, microcatheter time, number of balloon inflations, and total balloon inflation time. CONCLUSION: Immediate postembolization CT may show focal cortical hyperdensity following uneventful endovascular aneurysm treatment, most likely caused by blood-brain barrier disruption resulting in accumulation of contrast medium. The hyperdensity was more frequent when balloon assistance was used but was also seen in the patients with no balloon use. It is important to differentiate this clinically insignificant finding from possible hemorrhage, which would affect patients' immediate postprocedural medical management.

A contribution to the controversy over dimethyl sulfoxide toxicity: anesthesia monitoring results in patients treated with Onyx embolization for intracranial aneurysms.

Onyx injection is a new technique for embolization of cerebral aneurysms that is involved in a controversy about the 'toxicity' of its solvent, dimethyl sulfoxide (DMSO). We retrospectively studied 38 patients treated for aneurysms with the liquid polymer, Onyx. Induction was with propofol, fentanyl and vecuronium, and anesthesia was maintained with isoflurane in O2 and N2O. The patients were given 500 ml of fluid after induction, and bradycardia was prevented in order to keep patients hyperdynamic. Electrocardiography (ECG), non-invasive blood pressure (NIBP), pulse oximetry, core temperatures, invasive blood pressure (BP), etCO2, and urine output were monitored throughout the intervention. Heart rate and BP changes in response to balloon inflation, DMSO injection, Onyx injection and balloon deflation were recorded. The patients were followed with serial neurological examinations, computerized tomography and/or magnetic resonance imaging postoperatively for evidence of any neurological injury. Cumulative DMSO doses were always well under previously implicated doses for systemic toxicity. No changes implicating toxic reactions were observed during DMSO and Onyx injections. Balloon-induced changes returned to baseline within 1 min of balloon deflation. Technique-related permanent morbidity occurred in two patients (worsening of cranial nerve palsies in one and monocular blindness in another) and intracranial hemorrhage with resulting death in one patient. All patients showed a tendency to oxygen desaturation, but this finding did not cause any clinical consequence. Anesthesiologists need to be vigilant in monitoring patients treated with techniques that are new or are being developed. We have seen no evidence of toxicity or any anesthetic complications in our group of patients, our only clinical concern being a tendency to oxygen desaturation, which may be explained by the inhalational elimination of DMSO.

Endovascular treatment of kissing aneurysms at the fenestrated basilar artery. Case report with literature review.

BACKGROUND: Basilar artery fenestrations are most commonly located in the proximal basilar trunk close to the vertebrobasilar junction and may harbor saccular aneurysms. Surgical treatment of such aneurysms has been reported in several cases previously, despite the difficulty of the surgical approach. Endovascular treatment may provide a more convenient treatment alternative in such cases. This case is also interesting in that two discrete aneurysms arise from each limb of the fenestration. CASE REPORT: A 20-year-old man presented with acute subarachnoid hemorrhage. He had two kissing aneurysms at the fenestrated proximal basilar artery as demonstrated by MRA and selective angiography. The two aneurysms were successfully treated with GDCs via the contralateral vertebral arteries. One-year control angiogram showed stable occlusion. CONCLUSION: Aneurysms at the fenestrated basilar artery may be effectively treated with endovascular coil occlusion. The occurrence of multiplicity and the treatment alternatives are discussed, with relevant literature review.

Comparison of MR sequences in early cerebral infarction at 0.5 T.

PURPOSE: To compare the diagnostic values of fluid-attenuated inversion recovery (FLAIR) and gradient spin-echo (GRASE) with those of conventional spin-echo (SE) and fast SE T2-weighted sequences in the evaluation of acute cerebrovascular lesions at 0.5 T. MATERIAL AND METHODS: Twenty-two consecutive patients with the clinical diagnosis of acute cerebrovascular accident were examined by MR imaging within the first 48 h of ictus. MR examination included 5-mm axial conventional SE and turbo SE (TSE) T2-weighted, dual-echo GRASE and FLAIR sequences. The patients also had pre- and postcontrast T1-weighted axial images. Two examiners evaluated the images and scored the conspicuity of the acute lesions. RESULTS: Regardless of location, FLAIR provided the best lesion conspicuity in the detection of acute infarcts, followed by the GRASE sequence. In the posterior fossa, TSE and SE demonstrated the lesions better than GRASE and FLAIR techniques. In the detection of hemorrhagic elements within the ischemic region, TSE demonstrated statistically significant superiority over other sequences. CONCLUSION: In the detection of acute ischemic lesions in locations other than the posterior fossa, FLAIR provided the best lesion conspicuity among four T2-weighted sequences, including SE, TSE, GRASE and FLAIR. However, for the posterior fossa examination, preference of SE or TSE T2-weighted sequences is suggested.

Endovascular coil embolization of residual or recurrent aneurysms after surgical clipping.

PURPOSE: Treatment of residual or recurrent aneurysms after surgical clipping is a challenge and most surgeons prefer to avoid a second surgical attempt. We present treatment of 4 residual or recurrent aneurysms after surgical clipping with electrolytically detachable coils. MATERIAL AND METHODS: In 3 of 4 patients, recurrent aneurysms were diagnosed with angiography 2 months, 5 years and 14 years after surgery, although the domes of the aneurysms were opened following clipping during the surgery. In the 4th patient, an early postoperative angiogram revealed filling of a residual aneurysm secondary to the incomplete neck clipping. Guglielmi detachable coils were used to occlude the residual or recurrent aneurysm. RESULTS: The endovascular approach was successful in all patients and the control angiograms showed complete obliteration of the aneurysms with no recanalization. CONCLUSION: The endovascular approach is a good treatment option for patients in whom complete obliteration of the aneurysm cannot be achieved by surgical clipping. Opening of the aneurysm sac after clipping does not necessarily preclude aneurysm regrowth from a neck remnant proximal to the clip.

Gadodiamide as an alternative contrast medium in cerebral angiography in a patient with sensitivity to iodinated contrast medium.

The physical and pharmacological properties of gadolinium enable its chelates to be used as a contrast medium in digital subtraction angiography. We report the use of gadodiamide, a low-osmolar nonionic gadolinium chelate, for selective angiography in a patient with known sensitivity to iodinated contrast medium. No adverse effects were encountered during or after injection. Contrary to a single previous report of the use of these agents in cerebral angiography, contrast in the angiogram was not particularly good, especially in the distal circulation, but the angiogram was diagnostic.

Interlocking detachable coil occlusion in the endovascular treatment of intracranial aneurysms: preliminary results.

PURPOSE: To present our preliminary experience with the recently developed interlocking detachable coils in the treatment of intracranial aneurysms. METHODS: Two aneurysms of the basilar tip, two of the internal carotid artery, and one of the posterior inferior cerebellar artery were treated by an endovascular technique using interlocking detachable coils. Three of the patients had undergone unsuccessful surgical clipping. Three-month and 1-year control angiograms were obtained. RESULTS: In all patients but one, who had an aneurysm of the internal carotid artery, the aneurysmal sac was occluded with preservation of the parent artery and did not show recanalization on the follow-up control angiograms. In the other patient who had a wide-necked aneurysm of the internal carotid artery, the sac could not be totally obliterated and showed contrast filling in the neck remnant at 3-month angiography. None of the patients experienced neurologic deficit after treatment. CONCLUSION: Because they are soft and retrievable, interlocking detachable coils, with their immediate coil release design, may provide an alternative to surgery in the future treatment of endovascular aneurysms.

Placement of mechanically detachable spiral coils in the endovascular treatment of intracranial aneurysms. Work in progress.

PURPOSE: To determine the usefulness of mechanically detachable spiral tungsten coils (MDSs) in the endovascular, endosaccular occlusion of intracranial aneurysms. MATERIALS AND METHODS: Anterior communicating artery aneurysms shown at angiography in two patients and a basilar tip aneurysm shown in one patient were treated with MDSs. RESULTS: In the basilar artery aneurysm, eight coils were delivered. Two additional coils were placed at 3 months because of filling of the residual aneurysm neck. Angiography at 1 year showed no recanalization. The smaller aneurysm in the anterior communicating artery was totally occluded by a single coil. Angiography at 6 months showed no recanalization. The other aneurysm was occluded by two coils, with a small amount of residual filling. A third coil was withdrawn before detachment. The patient had aspiration pneumonia and electrolyte imbalance, but he was in stable condition 3 weeks later and was discharged. CONCLUSION: The pliable, soft, retrievable MDS system provides instantaneous release of a spiral coil.

Peritoneal mesothelioma: sonographic findings in nine cases.

Ultrasonographic findings in nine cases of peritoneal mesothelioma are presented. The most common findings were sheet-like or nodular peritoneal thickening, soft tissue masses, fixation of the intestinal loops, mesenteric thickening, and minimal ascites which was disproportional to the degree of tumor dissemination. The authors found that abdominal sonography, using 3.75-7.5 MHz transducers, is a useful imaging method for diagnosis of peritoneal mesothelioma in high-risk groups.