A Case of Symptomatic Common Carotid Artery Occlusion Treated by a Bridging Bypass Using Short Saphenous Vein Graft.

An 86-year-old woman with initially asymptomatic severe right common carotid artery stenosis had frequent transient left hemiparesis 2 years after the initial diagnosis. Magnetic resonance angiography and three-dimensional computed tomography angiography demonstrated short-segment occlusion of the right carotid bifurcation with significant circumferential calcification, while magnetic resonance imaging demonstrated no ischemic lesions. No collateral blood flow through the anterior communicating artery and posterior communicating artery was observed. A bridging bypass from the distal common carotid artery to the proximal cervical internal carotid artery using a saphenous vein graft was made. There were no ischemic symptoms following the procedure. Bridging bypass using the short saphenous vein graft might be useful for short-segment common carotid artery occlusion.

When Is Diagnostic Subtraction Angiography Indicated Before Clipping of Unruptured and Ruptured Intracranial Aneurysms? An International Survey of Current Practice.

INTRODUCTION: The goal of this survey is to investigate the indications for preoperative digital subtraction angiography (DSA) before clipping of ruptured and unruptured intracranial aneurysms in an international panel of neurovascular specialists. METHODS: An anonymous survey of 23 multiple-choice questions relating to indications for DSA before clipping of an intracranial aneurysm was distributed to the international panel of attendees of the European-Japanese Cerebrovascular Congress (EJCVC), which took place in Milan, Italy on 7-9 June 2018. The survey was collected during the same conference. Descriptive statistics were used to analyze the data. RESULTS: A total of 93 surveys were distributed, and 67 (72%) completed surveys were returned by responders from 13 different countries. Eighty-five percent of all responders were neurosurgeons. For unruptured and ruptured middle cerebral artery (MCA) aneurysms without life-threatening hematoma, approximately 60% of responders perform surgery without preoperative DSA. For aneurysms in other locations than MCA, microsurgery is done without preoperative DSA in 68% of unruptured and in 73% of ruptured cases. In cases of ruptured MCA or ruptured non-MCA aneurysms with life-threatening hematoma, surgery is performed without DSA in 97% and 96% of patients, respectively. Factors which lead to preoperative DSA being performed were: aneurysmal shape (fusiform, dissecting), etiology (infectious), size (>25 mm), possible presence of perforators or efferent vessels arising from the aneurysm, intra-aneurysmal thrombus, previous treatment, location (posterior circulation and paraclinoid aneurysm) and flow-replacement bypass contemplated for final aneurysm treatment. These are all factors that qualify an aneurysm as a complex aneurysm. CONCLUSION: There is still a high variability in the surgeons' preoperative workup regarding the indication for DSA before clipping of ruptured and unruptured intracranial aneurysms, except for ruptured aneurysms with life-threatening hematoma. There is a general consensus among cerebrovascular specialists that any angioanatomical feature indicating a complex aneurysm should lead to a more detailed workup including preoperative DSA.

The Hybrid Neurosurgeon: The Japanese Experience.

OBJECTIVE: In Japan, hybrid neurosurgeons who perform both open surgical clipping as well as endovascular embolization for the treatment of intracranial aneurysms are common. Although many Japanese neurosurgeons can perform surgical clipping of middle cerebral artery aneurysms or internal carotid artery-posterior communicating artery aneurysms and coil embolization of cerebral aneurysms using simple techniques-only a limited number of neurosurgeons are able to perform surgical clipping and endovascular procedures for anterior communicating artery aneurysms, paraclinoid, or posterior circulation aneurysms using both treatment modalities equally and safely. MATERIALS AND METHODS: The senior author's personal experience of more than 500 cases each of surgical clipping and endovascular embolization over the past 25 years included 110 cases of basilar tip aneurysms and 104 cases of paraclinoid internal carotid artery (ICA) aneurysms. RESULTS: The safety and efficacy of both treatments appears to be the same, while the durability of surgical clipping is superior to that of endovascular embolization. Among the 110 basilar tip aneurysms, 18 patients were treated by surgical clipping and 94 were treated by endovascular embolization. The initial results of endovascular therapy seemed to be better than those of surgical clipping, although the rate of retreatment was higher. Among the 104 cases of paraclinoid ICA aneurysm, 23 patients were treated by surgical clipping and 81 were treated by endovascular embolization. The results of both treatments seemed to be same, while surgical clipping had apparently good long-term durability. Over the past 15 years, the frequency of surgical clipping for basilar tip aneurysms has decreased, and the procedure may eventually be abandoned for this type of aneurysm. However, surgical clipping still offers several advantages in the treatment of paraclinoid aneurysms. CONCLUSIONS: Hybrid neurosurgeons can make reasonable decisions concerning the choice of treatment for cerebral aneurysms, as they perform both treatments and understand the benefits and drawbacks of each modality.

Attempt to delineate occluded arteries with initial plain computed tomography in acute cerebral arterial occlusion.

BACKGROUND: We used initial plain computed tomography to delineate acutely occluded internal carotid arteries or horizontal segments of middle cerebral arteries. If affected arteries could be delineated using initial plain computed tomography, useful information might be obtained that could support endovascular thrombectomies. METHODS: In 15 patients with occluded internal carotid arteries or horizontal segments of middle cerebral arteries, the affected middle cerebral artery was automatically traced using the extender function for blood vessel tracing with reference to the default value (window setting, 40; window width, 90) on Ziostation 2 (Ziosoft Inc., Tokyo, Japan) based on initial plain computed tomography data. RESULTS: The horizontal and sylvian segments of the middle cerebral artery were delineated in 15 and nine patients, respectively, based on plain computed tomography volume data. Images of occluded vessels delineated by plain computed tomography closely correlated with digital subtraction angiography. CONCLUSIONS: Initial plain computed tomography combined with a new generation workstation enabled the rapid delineation of occluded segments of intracranial vessels and could provide useful information that might improve the safety of endovascular thrombectomy.

[A Case of Trochlear Nerve Neurinoma Presenting with Pathological Laughter].

Trochlear nerve neurinomas are rare and solitary tumors without neurofibromatosis are extremely rare. We report a case of trochlear nerve neurinoma presenting with pathological laughter and diplopia. A 40-year-old male patient presented with diplopia and pathological laughter 2 months before admission. MRI showed a multicystic enhanced mass in the left tentorial incisura compressing the midbrain and the upper pons. The tumor was excised using the left trans-Sylvian approach with partial uncal resection. After excision of the tumor, the left trochlear nerve was identified on the surface of the lateral midbrain. The nerve was connected to the tumor. Pathological laughter completely resolved after the operation. This is the second reported case of trochlear nerve neurinoma presenting with pathological laughter. The lesion responsible for pathological laughter could be the midbrain, upper pons, diencephalon, or all of these.

STA-MCA Bypass Under Local Anesthesia.

BACKGROUND AND AIMS: The superficial temporal artery to middle cerebral artery (STA-MCA) bypass procedure has continually evolved and new strategies have been advocated to reduce anesthetic or surgical mortality and morbidity. Further simplifying and decreasing the invasiveness of STA-MCA bypass by performing this operation without endotracheal general anesthesia was deemed feasible in certain subsets of patients. METHODS: We performed STA-MCA bypass using local anesthesia using a sedative in 45 patients with hemodynamically compromised cerebrovascular occlusive disease as well as multiple comorbidities in the period between February 2010 and April 2016. The technique is based on preoperative identification of the point at which the donor and recipient vessels are in closest proximity. The preoperative use of computed tomography angiography allowed us to identify the target point precisely and use a minimally invasive procedure. All patients received dexmedetomidine as the sole sedative agent, together with scalp block local anesthesia with an unsecured airway. RESULTS: Successful STA-MCA bypass surgeries were achieved via a preselected minimally invasive approach in all cases. There was good hemodynamic stability throughout surgery. No airway/ventilation complications occurred and no patient was converted to general anesthesia. The patients subjectively tolerated this technique well with a high rate of satisfaction. Postoperative magnetic resonance angiography confirmed patent bypass in 44 of 45 patients (patency rate of 97.8%). There were two postoperative hyper-perfusion syndromes and one cerebral ischemia with transient neurological symptoms (postoperative complication rate of 6.3%). No recurrence of ipsilateral cerebral ischemia was observed during the follow-up periods. There was one contralateral cardiogenic cerebral embolism during the follow-up period. The overall stroke rate was calculated as 1%/patient/year. CONCLUSIONS: Our initial experience confirms the feasibility of performing STA-MCA bypass under local anesthesia without endotracheal general anesthesia.

In-stent hypodense area at two weeks following carotid artery stenting predicts neointimal hyperplasia after two years.

Introduction It has not been reported how long the follow-up study after carotid artery stenting (CAS) should be continued. The purpose of the present study is to clarify the dynamic change of the in-stent neointimal layer and residual arterial lumen by two years following CAS using three-dimensional computed tomography angiography (3D CTA) with volume rendering. Methods Thirty-six stented carotid arteries in 34 consecutive patients were examined by 3D CTA with volume rendering at two weeks and 3, 6, 12, 24 months of follow-up. Results An in-stent hypodense area could be detected in 10 of 36 (27.8%) carotid arteries at two weeks after CAS. In-stent hypodense areas gradually declined thereafter by three months. In the course of longer follow-up, the layer of the in-stent hypodense area (neointimal hyperplasia) continued to grow in size for up to 24 months. Patients with an in-stent hypodense area at two weeks have a thicker layer of neointimal hyperplasia at 24 months than patients without in-stent hypodense area at two weeks' follow-up. The predictive factors for growing neointimal hyperplasia at 24 months in multiple regression analysis are ulcer formation in pretreatment stenosis and the thickness of in-stent hypodense area at two weeks following CAS. Conclusion Our results suggest that follow-up study should be continued for a longer period even if in-stent restenosis could not be detected at one year following CAS. Especially in cases with ulcer formation in pretreatment stenosis and with a subacute in-stent hypodense area after CAS, longer follow-up is strongly recommended.

Stent-assisted coil embolization of a recurrent posterior cerebral artery aneurysm following surgical clipping.

Posterior cerebral artery (PCA) aneurysms are rare, and direct surgery of these is considered difficult. Coil embolization of PCA aneurysms is becoming popular. However, it is difficult to completely obliterate the aneurysm while preserving the flow of the parent artery in large or giant PCA aneurysms with a wide neck with this technique. We report a case of a large and wide-necked PCA aneurysm with multiple recurrences following successful surgical clipping and coil embolization. A 77-year-old man with a large unruptured right PCA (P2) aneurysm was successfully treated by surgical clipping. Postoperative digital subtraction angiography (DSA) showed complete aneurismal occlusion. Four years afterward, the aneurysm recurred and grew toward the contralateral. Surgical retreatment of this complicated aneurysm was considered difficult, with a substantial risk of complications. Therefore, the aneurysm was treated with an endovascular procedure. Because simple coil embolization was not expected to achieve satisfactory obliteration of the aneurysm with preservation of parent artery patency, we used stent-assisted coil embolization. The patient tolerated the treatment well. On DSA obtained six months after the first endovascular treatment, coil compaction and recanalization of the aneurysm were detected. A second coil embolization was successfully performed without any complications. The aneurysm was stable during the next six-month follow-up. Stent-assisted coil embolization may be feasible and effective for such postoperatively complicated aneurysms.

Surgical Treatment of Complex Cerebral Aneurysms Using Interposition Short Vein Graft.

BACKGROUND AND AIMS: Cerebral revascularization strategies may become necessary in select patients who present with challenging cerebral aneurysms. In this study, we present the techniques of a moderate-flow extra-intracranial bypass using a short interposition vein graft and concurrent aneurysm management. METHODS: The short interposition vein graft was used for the reconstruction of complex cerebral aneurysms in nine patients. In eight of them, the superficial temporal artery (STA) main trunk was used as a donor site for the anastomosis of a short interposition vein graft, and an extracranial vertebral artery (VA) was used in one case. The vein grafts were implanted into the M2 of the middle cerebral artery (MCA) for the adjunctive treatment of internal carotid artery (ICA) aneurysms in three patients, into the A3 of the anterior cerebral artery (ACA) in one patient, into the P2 of the posterior cerebral artery (PCA) for the adjunctive treatment of complex PCA aneurysms in three patients, into the P3 of the PCA for the adjunctive treatment of a basilar artery (BA) trunk giant aneurysm in 1 patient, and into the postero-inferior cerebellar artery (PICA) for the adjunctive treatment of the VA dissecting aneurysm in one patient. RESULTS: All of the bypasses were patent. Intraoperative flow measurements confirmed a moderate flow-carrying capacity of the short interposition short vein graft (30-70 ml; mean: 43 ml/min). CONCLUSION: The STA main trunk to proximal MCA/PCA bypass and the extracranial VA to PICA bypass using short interposition vein grafts can provide sufficient blood flow and may be a reasonable alternative to the conventional EC-IC bypass/high-flow bypass.

Surgical Approach to Ponto-mesencephalic Cavernoma.

BACKGROUND AND AIMS: The surgical treatment of intrinsic brainstem lesions remains a major challenge. In this article we present the results of using an infratentorial-supracerebellar (ITSC) approach for the resection of intrinsic ponto-mesencephalic lesions. MATERIALS AND METHODS: The authors reviewed the cases of 16 patients. In seven of them, a paramedian ITSC transcollicular approach was used to resect intrinsic mid-brain lesions, and in the other nine patients, an intermediate or lateral ITSC infra-trochlear approach was used for ponto-mesencephalic lesions. RESULTS: All 16 lesions were completely removed. There was no recurrence of bleeding during the follow-up period, and no mortality. In seven patients with mid-brain lesions, the preoperative ocular symptoms improved in three of them, and the neurological deficits - other than ocular symptoms improved - in five of them. The preoperative modified Rankin Scale score of 1.8 improved to 1.3 postoperatively. In nine patients with a ponto-mesencephalic lesion, the preoperative ocular symptoms improved in four of nine patients, and the neurological deficits other than ocular symptoms improved in five of them, while one patient exhibited venous infarction in a cerebellar hemisphere that caused neurological deterioration. The preoperative modified Rankin Scale score of 3.75 improved to 2.5 postoperatively in these patients. CONCLUSION: The ITSC transcollicular or infra-trochlear approach provide a wide operative entry zone and minimize the functional damage to the surrounding structures for access to ponto-mesencephalic lesions.

STA-MCA/STA-PCA Bypass Using Short Interposition Vein Graft.

BACKGROUND AND AIMS: Superficial temporal artery (STA) is the mainstay of donor vessels for extra-intracranial bypass (EC-IC bypass) in cerebral revascularization. However, the typically used STA frontal or parietal branch is not always adequate in its flow-carrying capacity. In the present study, we provide an update on an alternative strategy: the use of the STA main trunk as a donor vessel, with a short vein interposition graft. METHODS: Seven patients in whom the STA main trunk was used as a donor site for anastomosis of a short interposition vein graft were included. The grafts were implanted into the M2 of the middle cerebral artery for adjunctive treatment of IC anterior wall blood-blister aneurysms in two patients, for revascularization of an internal carotid artery occlusion in one patient, into the P2/3 of the posterior cerebral artery (PCA) for adjunct treatment of complex PCA aneurysms in three patients and into the P3 of PCA for adjunct treatment of basilar artery (BA) trunk giant aneurysm in one patient. RESULTS: All the bypasses were patent. Intraoperative flow measurements confirmed a moderate flow-carrying capacity of the STA main trunk-interposition short vein graft (20-50 ml; mean 43 ml/min). CONCLUSION: The STA main trunk has a larger diameter than the distal branch; therefore, it would be expected to have a significantly higher flow capacity than its branches. STA main trunk to proximal MCA/PCA bypass using short interposition vein grafts can provide sufficient blood flow, and may be a reasonable alternative to ECA to MCA/PCA bypass using long vein grafts.

Superficial temporal artery-middle cerebral artery bypass using local anesthesia and a sedative without endotracheal general anesthesia.

OBJECT: Superficial temporal artery (STA)-middle cerebral artery (MCA) bypasses have continually evolved, and new strategies have been advocated for reducing anesthetic or surgical morbidity and mortality. Further simplifying, and decreasing the invasiveness of, STA-MCA bypass by performing this operation without endotracheal general anesthesia was believed to be feasible in certain subsets of patients. METHODS: The authors performed STA-MCA bypass using local anesthesia with a sedative in 10 patients with hemodynamically compromised occlusive cerebrovascular disease, as well as multiple comorbidities, between February 2010 and September 2011. The technique is based on the preoperative identification of the point at which the donor and recipient vessels are in closest proximity. Preoperative use of CT angiography allowed the authors to identify the target point precisely and use a minimally invasive procedure. All patients received dexmedetomidine as the sole sedative agent, together with scalp-blocking local anesthesia, with an unsecured airway. RESULTS: Successful STA-MCA bypass surgeries were achieved via a preselected minimally invasive approach in all cases. There was good hemodynamic stability throughout surgery. No airway or ventilation complications occurred, and no patients were converted to general anesthesia. Subjectively, patients tolerated the technique well with a high rate of satisfaction. There were no perioperative morbidities or deaths. Postoperative MR angiography confirmed a patent bypass in all patients. All patients remained symptom free and returned to normal daily life following the operation. CONCLUSIONS: This initial experience confirms the feasibility of performing STA-MCA bypass without endotracheal general anesthesia. This novel technique produced a high degree of patient satisfaction.

Pure vasogenic edema caused by cerebral hyperperfusion after superficial temporal artery to middle cerebral artery anastomosis--case report.

A 63-year-old patient presented with cerebral hyperperfusion manifesting as transient aphasia and general tonic convulsions 3 and 4 days after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. Diffusion-weighted magnetic resonance (MR) imaging revealed a focal low-intensity area at the site of anastomosis in the left temporal lobe, with high apparent diffusion coefficient, together with focal intense increase in cerebral blood flow in the same region. This lesion was considered to be pure vasogenic edema caused by cerebral hyperperfusion. Additional treatment with intravenous drip infusion of free radical scavenger and reduction in blood pressure with nicardipine improved the patient's symptoms and brain edema. The brain edema gradually decreased on MR imaging and completely disappeared at 3 months after bypass surgery. Cerebral hyperperfusion is often encountered after recanalization of occlusive arteries, removal of arteriovenous malformations, and carotid endarterectomy, but may also occur after STA-MCA anastomosis.

Treatment of ruptured cerebral aneurysms - clip and coil, not clip versus coil.

BACKGROUND AND AIMS: Recent advances in neurosurgery and interventional neuroradiology have brought us a new aspect in the treatment of cerebral aneurysms. The present single-surgeon series provides a balanced overview of the treatment of ruptured aneurysms in surgical clipping and coil embolization. CLINICAL MATERIALS AND METHODS: One hundred consecutive patients with ruptured cerebral aneurysms underwent surgical clipping or endovascular coil embolization between January 2005 and December 2007. All patients underwent clipping or coil embolization of at least one ruptured cerebral aneurysm by a single neurosurgeon (YK) who performed both the surgical clipping and endovascular coiling. RESULTS: Of the 48 surgically treated patients, 37 (77.1%) achieved a favorable outcome. Of the 52 patients who underwent endovascular embolization, 37 (71.2%) achieved a favorable outcome. No significant difference was observed regarding the proportion of favorable outcomes between the two treatment modalities. Five patients (9.6%) who underwent endovascular embolization needed re-treatments, while no re-treatment was necessary in the surgically treated patients. The rates of symptomatic vasospasm and shunt dependent hydrocephalus were 18.8% and 14.6%, respectively, in the clipped patients, and 19.2% and 21.2%, respectively, in the coiled patients. Endovascular coiling of ruptured aneurysms has a tendency towards a higher risk of developing shunt dependent hydrocephalus. CONCLUSION: A combined microsurgical-endovascular approach can achieve the best outcomes for patients with ruptured cerebral aneurysms. Our findings support the policy of "Clip and Coil, not Clip versus Coil."

Follow-up study on in-stent thrombosis after carotid stenting using multidetector CT angiography.

INTRODUCTION: The purpose of the present study was to evaluate the role of multidetector three-dimensional computed tomography angiography (3D CTA) for evaluating both the residual arterial lumen and the sequential change in the intraluminal diameter and thrombus formation following carotid artery stenting (CAS). MATERIALS AND METHODS: Twenty consecutive patients consisting of 23 successfully stented carotid arteries were examined by 3D CTA with volume-rendering at 2, 4, 8, 12 weeks and 6, 12 months of follow-up. RESULTS: The eccentric in-stent hypodense area could be detected in ten of 23 (43.5%) carotid arteries at 2 weeks of follow-up, and they then gradually declined until they almost disappeared at 12 weeks. Eccentric in-stent hypodense areas in the acute and subacute phase (up to 12 weeks after CAS) were found in nine out of 16 carotid arteries with longer stents (3 or 4 cm in size) deployed across the carotid bifurcation, whereas no eccentric in-stent hypodense area could be observed in the patients with a short stent (2 cm) deployed only to the internal carotid artery. Seven of the ten observed eccentric hypodense areas presented on the dorsal surface at the carotid bifurcation level. CONCLUSION: Carotid 3D CTA for evaluating residual lumen and in-stent thrombus formation after CAS is considered to be a useful diagnostic method. To avoid stent occlusion, both the acute and subacute phases following CAS (up to 12 weeks) call for the administration of appropriate anti-platelet therapy and careful observations of the patients.

Cerebral aneurysms: conventional microsurgical technique and endovascular method.

Recent advances in neurosurgery and interventional neuroradiology have brought us a new aspect in the treatment of cerebral aneurysms. The present series provides a balanced overview of the treatment of aneurysms in surgical clipping and coil embolization. Between January 2004 and March 2006, a total of 119 consecutive patients with cerebral aneurysms underwent endovascular embolization or surgical clipping. Of these, 79 patients suffered an aneurysmal subarachnoid hemorrhage (SAH), whereas the remaining 40 patients had nonruptured cerebral aneurysms. Of the 32 surgically treated patients, 25 (78.1%) achieved a favorable outcome. Of the 47 patients who underwent endovascular embolization, 38 (80.9%) achieved a favorable outcome. No significant difference was observed regarding the proportion of favorable outcomes between the two treatment modalities. Four patients (5.5%) who underwent endovascular embolization required re-treatments but no re-treatments were needed in the surgically treated patients. Of the 40 cases with nonruptured aneurysms, 12 (30%) were treated using surgical clipping, whereas 28 (70%) underwent endovascular embolization. The complication rates of the two treatment modalities demonstrated no significant difference. A combined microsurgical-endovascular team approach is thus considered to provide the most effective means to achieve favorable outcomes for patients with cerebral aneurysms. A case-by-case evaluation based on the individual characteristics of each aneurysm is therefore considered to be essential.

Thrombosed unruptured cerebral aneurysm causing brain infarction followed by subarachnoid hemorrhage--case report--.

A 71-year-old man presented with right hemiparesis and aphasia due to cerebral infarction in the frontal lobe. Computed tomography (CT) revealed a high-density mass, 12 mm in diameter, in the stem of the left sylvian fissure. Carotid angiography demonstrated occlusion of the left ascending frontal artery complex and retention of contrast medium at the bifurcation of the left middle cerebral artery (MCA). The diagnosis was cerebral infarction caused by occlusion of the ascending frontal artery complex resulting from thrombosed left MCA aneurysm. The patient was managed conservatively and his neurological symptoms gradually improved. One month later, he lapsed into a coma. CT revealed subarachnoid hemorrhage. Carotid angiography showed a large left MCA aneurysm with branch occlusion of the left ascending frontal artery complex. A left frontotemporal craniotomy was performed. The MCA aneurysm was opened and the intramural thrombi removed, and finally neck clipping was performed. The patient made a good postoperative recovery.

Two cases of dissecting aneurysm of the distal posterior inferior cerebellar artery: possible involvement of segmental mediolytic arteriopathy in the pathogenesis.

BACKGROUND: Dissecting aneurysm of the posterior inferior cerebellar artery (PICA) uninvolved with the vertebral artery is rare. The exact pathohistological diagnosis might result in 'unknown' because the underlying pathoanatomical features are, for a variety of reasons, not always identified. CASE DESCRIPTION: We report herein two cases of dissecting aneurysm harbored in different segments of the distal posterior inferior cerebellar artery. In our cases, after trapping the PICA at both just proximal and distal to the aneurysm, the abnormal portion was successfully resected with/without an end-to-end anastomosis. The first patient made a good recovery, while the other died 2 days after the surgery. Although its pathogenetic etiology was unidentified in the second case, the formation of dissecting aneurysm had resulted from a segmental mediolytic arteriopathy in the first case. CONCLUSION: This is the first report of a segmental mediolytic arteriopathy possibly being identified as causing an isolated dissecting aneurysm at this site.

Antegrade recanalization of a completely embolized vertebral artery after endovascular treatment of a ruptured intracranial dissecting aneurysm. Report of two cases.

Occlusion of the parent artery is a traditional method of treatment of unclippable cerebral aneurysms. Surgical or endovascular occlusion of the parent artery proximal to the aneurysm has been recommended for the treatment of dissecting aneurysms located in the vertebrobasilar circulation. Nevertheless, occlusion of the parent artery may not result in permanent exclusion of the aneurysm from the systemic circulation because, occasionally, postoperative rebleeding occurs after proximal occlusion. Alternatively, endovascular occlusion of the affected site, including the aneurysmal dilation, and parent artery, is a safe and reliable treatment for dissecting aneurysms. The authors present two rare cases of ruptured vertebral artery (VA) dissecting aneurysms that were treated by endovascular occlusion of the affected site including the aneurysm and parent artery by using Guglielmi detachable coils. In both cases the VA recanalized in an antegrade fashion during the follow-up period. Based on these unique cases, the authors suggest that a careful angiographic follow up of dissecting aneurysms is required, even in patients successfully treated with endovascular occlusion of the affected artery and aneurysm.

Factors predictive of cerebral hyperperfusion after carotid angioplasty and stent placement.

BACKGROUND AND PURPOSE: Cerebral hyperperfusion syndrome has been increasingly reported as a complication of carotid angioplasty and stent placement. The aim of the present study was to determine significant predictors of hyperperfusion phenomenon after carotid angioplasty and stent placement. METHODS: We retrospectively reviewed 30 consecutive patients with unilateral severe carotid stenosis who underwent angioplasty and stent placement. Resting cerebral blood flow (CBF) and cerebral vasoreactivity (CVR) to acetazolamide challenge were quantitatively measured to evaluate cerebral hemodynamic reserve. Split-dose [(123)I] iodoamphetamine single photon emission CT (SPECT) was performed before and 7 days after carotid angioplasty and stent placement. Technetium-99m hexamethylpropyleneamine oxime (HMPAO) SPECT was performed immediately after the procedure. RESULTS: Three patients had cerebral hyperperfusion phenomenon immediately after angioplasty and stent placement, as shown by HMPAO SPECT: One developed status epilepticus 2 weeks after the procedure. Significant predictors of hyperperfusion included patient age, pretreatment CVR, and pretreatment asymmetry index ([ipsilateral resting CBF/contralateral resting CBF] x 100). Variables determined not to be significant risk factors included pretreatment resting CBF value, degree of carotid stenosis, and interval from the onset of ischemic symptoms. CONCLUSION: Significant predictors of hyperperfusion phenomenon after carotid angioplasty and stent placement included patient age, pretreatment CVR, and pretreatment asymmetry index. Pretreatment CBF measurements, including those obtained by quantifying CVR and performing SPECT immediately after the procedure may aid in identifying patients at risk and in initiating careful monitoring and control of blood pressure to prevent hyperperfusion syndrome.