Osamu Hamasaki

Brain metastasis of Merkel cell carcinoma. Case report and review of the literature.

Abstract Merkel cell carcinoma (MCC) is a rare primary cutaneous neuroendocrine tumor that is locally aggressive and has potential for metastatic spread. However, brain metastases are rare, and therapy for such tumors has never reported. The authors present a 48-year-old woman with MCC of the left elbow and a right cerebellar metastasis. After the right cerebellar mass was totally resected, radiation treatment and chemotherapy were performed. Eight cases of brain metastasis have been reported in the literature, but only 5 have been presented in sufficient detail for analysis. Therapy for brain metastases has always been palliative whole-brain irradiation and chemotherapy except for our patient, who underwent total removal of the tumor and survived for 11 months without neurological deficit. Except in the case of 1 with a particularly radiosensitive MCC, the patients with brain metastases died within 9 months after detection of the brain lesions. If possible, aggressive excision of brain metastases as well as of the primary lesion should be done.

Stent-assisted angioplasty for intracranial atherosclerosis

We report on two patients with intracranial atherosclerosis of the carotid artery or vertebral artery treated with stent-assisted angioplasty. Both patients have severe intracranial atherosclerosis (>70%) with refractory symptoms despite optimal medical treatment. In both patients, a coronary balloon-expandable stent was successfully placed using a protective balloon technique without procedural complications. The patients were asymptomatic and neurologically intact at a mean clinical follow-up of 13 months. Follow-up angiograms did not show restenosis 3 or 4 months after procedure, respectively. Stent-assisted angioplasty for intracranial atherosclerosis in the elective patient has proven effective, with an acceptable low rate of morbidity and mortality.

Cerebrospinal Fluid Enhancement on Fluid Attenuated Inversion Recovery Images After Carotid Artery Stenting with Neuroprotective Balloon Occlusions: Hemodynamic Instability and Blood-Brain Barrier Disruption

PurposeA rare complication of carotid artery stenting (CAS), prolonged reversible neurological symptoms with delayed cerebrospinal fluid (CSF) space enhancement on fluid attenuated inversion recovery (FLAIR) images, is associated with blood–brain barrier (BBB) disruption. We prospectively identified patients who showed CSF space enhancement on FLAIR images.MethodsNineteen patients—5 acute-phase and 14 scheduled—underwent 21 CAS procedures. Balloon catheters were navigated across stenoses, angioplasty was performed using a neuroprotective balloon, and stents were placed with after dilation under distal balloon protection. CSF space hyperintensity or obscuration on FLAIR after versus before CAS indicated CSF space enhancement. Correlations with clinical factors were examined.ResultsCSF space was enhanced on FLAIR in 12 (57.1%) cases. Postprocedural CSF space enhancement was significantly related to age, stenosis rate, acute-stage procedure, and total occlusion time. All acute-stage CAS patients showed delayed enhancement. Only age was associated with delayed CSF space enhancement in scheduled CAS patients.ConclusionsIschemic intolerance for severe carotid artery stenosis and temporary neuroprotective balloon occlusion, causing reperfusion injury, seem to be the main factors that underlie BBB disruption with delayed CSF space enhancement shortly after CAS, rather than sudden poststenting hemodynamic change. Our results suggest that factors related to hemodynamic instability or ischemic intolerance seem to be associated with post-CAS BBB vulnerability. Patients at risk for hemodynamic instability or with ischemic intolerance, which decrease BBB integrity, require careful management to prevent intracranial hemorrhagic and other post-CAS complications.

Double Wire Technique for Intracranial Stent Navigation

Editor: Evolutionary advancement of stent technology allows us to expand the therapeutic options in the field of neuroendovascular treatment. Stent placement for extracranial carotid stenosis can be accomplished at a high rate with acceptably low rates of morbidity and mortality. These excellent results have encouraged neurointerventionalists to place stents for treatment of vascular stenoses and aneurysms involving intracranial vessels (1–3). To advance a stent delivery system in the intracranial vessels, the tip of the guide wire should be placed as distally as possible to allow the best support. The guiding catheter should be positioned as close to the base of the skull as possible to maintain good catheter support during stent navigation. In almost all patients in one reported series, intracranial stent deployment was performed successfully with use of these standard techniques; however, in some patients, this procedure failed to access the objective lesion because of vessel tortuosity. We describe a new technique that can successfully navigate a stent delivery system in these difficult cases. Vessel tortuosity from the base of the skull to intracranial lesions has limited the use of stent therapy. Acute angles of tortuous vessel limit the ability to cross the distal edge of the stent or balloon catheter and stent delivery systems often stop at this site (Figure, parts a, b). At this point, stent navigation with the standard technique should be stopped and the stent delivery system should be withdrawn, leaving the guide wire for the stent delivery system across the intracranial lesion. Another guide wire is advanced across the acute angled curve. Two guide wires are now positioned in the objective lumen. At this time, it is important to deliver the second guide wire on the path of the distal edge of the stent or balloon catheter. Then the stent delivery system is advanced again. When a bare guide wire exists between the arterial wall and the stent, the stent delivery system can pass the acute angled curve with significantly less resistance (Figure, parts c, d). The second guide wire is withdrawn when the stent is positioned at the level of interest, just before expansion. This technique can be adapted to vessels with reference diameters of at least 3 mm in because it is necessary to insert a stent delivery system and another guide wire though the same vessel. In the field of cardiovascular intervention, it is reported that placing stents in vessels smaller than 3 mm causes a higher incidence of acute complications (dissection and acute closure) and a higher incidence of restenosis during follow-up. Therefore, this double-wire technique may be used for the treatment of many intracranial lesions with intracranial stent placement. Endovascular stent placement for cerebrovascular disease has been proven to be a successful treatment option. Stents used for intracranial lesions of cerebral aneurysms or vascular stenoses have primarily been treated with coronary balloon-expandable stents (1–3). Second-generation coronary stents demonstrate excellent flexibility and “trackability” and allow for treatment of intracranial vascular lesions. This procedure promises a new therapeutic era. However, the safe and smooth navigation of a coronary stent system into intracranial lesions is difficult because there are significant differences in physical properties and architecture between the coronary and cerebral vasculatures. Stent system delivery across a tortuous carotid siphon or upper segment of vertebral artery is particularly difficult. Gomez et al (4) reported a 33% success rate of stent navigation into the intracranial carotid artery above the supraclinoid portion with use of standard technique. It is doubtful that uneventful passage of current coronary stent systems has been possible in all patients with cerebral arteriosclerosis. The stent delivery system should be not forced, but gently navigated into intracranial lesion. The friction seen between the distal edge of the stent and the arterial wall prevents smooth navigation of stent delivery systems, and forceful pushing may lead to tremendous complications including stent edge dissection or deformation or migration of the stent. Stent edge dissection can cause pseudoaneurysm, which may cause supraclinoid hemorrhage or cerebral embolism. The deformation and migration of the stent may lead to abrupt closure of the intracranial carotid artery and massive cerebral infarction. Therefore, a technique with safe and smooth intracranial stent navigation is required to perform this endovascular procedure without complications. In the doublewire technique, a second guide wire is placed parallel and adjacent to the stent delivery system. The adjacent wire appears to facilitate the advancement of the stent and stent delivery system in acutely angled vessels. The role of the adjacent wire is to provide a “railway” for the stent and stent delivery system. A possible mechanism for beneficial effects may be that the wire diminishes friction between the arterial wall and the stent delivery system. The adjacent wire should be stuck on a arterial wall and placed between the arterial wall and the stent. Another consideration is that the wire makes an obtuse angle to advance the stent delivery system. Therefore, we recommend selecting a 0.016or 0.014-inch guide wire with stiffness, steerability, and slippery surface as the adjacent wire. The disadvantage of this technique is that it requires additional complex manipulation. It should be considered that a more complex procedure increases the risk of thromboembolic complications compared to the standard technique. Therefore, we believe that strict anticoagulation therapy is needed to prevent thromboembolism durDOI: 10.1097/01.RVI.0000071092.76348.2E Letter to the Editor

Treatment of ruptured vertebral artery dissecting aneurysms. A short report.

We evaluated the outcomes of endovascular or surgical treatment of ruptured vertebral artery dissecting aneurysms (VADAs), and investigated the relations between treatment complications and the development and location of the posterior inferior cerebellar artery (PICA). We treated 14 patients (12 men, two women; mean age, 56.2 years) with ruptured VADAs between March 1999 and June 2012 at our hospital. Six and eight patients had Hunt and Hess grades 1–3 and 4–5, respectively. Twelve patients underwent internal endovascular trapping, one underwent proximal endovascular occlusion alone, and one underwent proximal endovascular occlusion in the acute stage and occipital artery (OA)-PICA anastomosis and surgical trapping in the chronic stage. The types of VADA based on their location relative to the ipsilateral PICA were distal, PICA-involved, and non-PICA in nine, two, and three patients, respectively. The types of PICA based on their development and location were bilateral anterior inferior cerebellar artery (AICA)-PICA, ipsilateral AICA-PICA, extradural, and intradural type in one, two, two, and nine patients, respectively. Two patients with high anatomical risk developed medullary infarction, but their midterm outcomes were better than in previous reports. The modified Rankin scale indicated grades 0–2, 3–5, and 6 in eight, three, and three patients, respectively. A good outcome is often obtained in the treatment of ruptured VADA using internal endovascular trapping, except in the PICA-involved type, even with high-grade subarachnoid hemorrhage. Treatment of the PICA-involved type is controversial. The anatomical location and development of PICA may be predicted by complications with postoperative medullary infarction.

Extracranial Internal Carotid Artery Pseudoaneurysm Associated With Neurofibromatosis Type 1 Treated With Endovascular Stenting and Coil Embolization

An internal carotid artery (ICA) pseudoaneurysm associated with neurofibromatosis type 1 (NF-1) is rare. We report the first case of unruptured extracranial pseudoaneurysm of the ICA in a patient with NF-1 successfully treated with endovascular stenting and coil embolization.A 66-year-old woman diagnosed with NF-1 had sudden left neck pain and massive swelling 3 years earlier. Radiological examination showed a ruptured pseudoaneurysm of the left internal thoracic artery (ITA). The posttreatment computed tomography (CT) scan revealed complete obliteration of the aneurysm of the left ITA and an unruptured pseudoaneurysm of the right ICA. After 3 years of follow-up, a CT scan revealed the enlargement of the pseudoaneurysm of the right extracranial ICA. Endovascular stenting and coil embolization were performed to prevent rupture, and the lesion was completely obliterated. Follow-up angiography at 6 months revealed good flow of the ICA through the stent without any filling of the aneurysm.

Post-Mortem Pathological Examination of Two Patients after Intraaneurysmal Embolization Using Guglielmi Detachable Coils

We report the histological findings in two patients treated using Guglielmi detachable coils with almost complete occlusion of the aneurysms. Autopsies of these patients were performed one week and one year after GDC embolization respectively. In one aneurysm that was obtained at autopsy one week after embolization, the histological findings revealed coils and an unorganized thrombus-filled aneurysm sac; an incomplete cell-lining on the luminal side of fibrin thrombi in the region of the neck of the aneurysm was recognized. In the other aneurysm in which autopsy was performed one year after embolization, an organized fibrous tissue at the margin of the aneurysmal wall and vascular granulation tissue at the center of the aneurysm were observed. There is a single layer of endothelium covering fibrous tissue in the neck of the aneurysm. We discuss the healing process after GDC treatment.

A case of MELAS showing both cytotoxic and vasogenic edema on serial diffusion-weighted imaging

Abstract In patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), T2-, FLAIR, and diffusion-weighted imaging reveal lesions as hyperintense areas after stroke-like episodes. It has been speculated that the lesions occur by vasogenic edema. However, we describe a case of MELAS which presented both normal and restricted water diffusion after stroke-like episodes, as detected by apparent diffusion coefficient map and values. Both cytotoxic and vasogenic edema can occur at acute stage after stroke-like episodes.

Factors Related to Frailty Associated with Clinical Deterioration After Meningioma Surgery in the Elderly

BACKGROUND Older patients are increasingly presenting for surgery with intracranial meningioma because of progress with diagnostic imaging and longer life expectancy. However, older patients have many problems, such as comorbidities and reduced physiological capacity reflected in the frailty index. This study examines the factors affecting clinical deterioration after surgery in older patients, particularly factors associated with frailty. METHODS Two hundred sixty-five patients older than 65 years underwent surgical resection of meningioma at Hiroshima University and related hospitals between 2000 and 2016. Karnofsky Performance Status (KPS) scores before and after surgery were evaluated. Factors related to the deterioration of KPS were analyzed with multivariate logistic regression modeling, including body mass index and serum albumin. RESULTS KPS score deteriorated compared with preoperative score in 56 patients at discharge and in 40 patients at 3 months later, and 2 patients died within 1 year after surgery. Multivariate logistic regression analysis in addition to preoperative body mass index and serum albumin indicated skull base tumor location (odds ratio [OR], 4.67; 95% confidence interval [CI], 2.02-10.8) and serum albumin (OR, 2.38; 95% CI, 1.06-5.34) were risk factors for deterioration of KPS score at discharge. Age (OR, 0.91; 95% CI, 0.85-0.98), skull base tumor location (OR, 4.32; 95% CI, 1.45-12.9), tumor size (OR, 1.03; 95% CI, 1.00-1.05), and serum albumin (OR, 3.53; 95% CI, 1.29-9.61) were significant risk factors for perioperative intracranial complications. CONCLUSIONS Skull base tumor location and serum albumin correlated with deterioration of clinical status after surgery.

A case of transient hypothermia after trans-lamina terminalis and third ventricle clipping of an extremely high-position basilar tip aneurysm

Reports on the trans-lamina terminalis and trans-third ventricular approach are rare. The risk associated with this approach is unknown. After an unsuccessful endovascular surgery, we performed direct surgical clipping via the third ventricle on a 78-year-old woman presenting with an extremely high-positioned, ruptured basilar tip aneurysm. She experienced transient hypothermia for 5 days, and it was considered that this was due to hypothalamic dysfunction. It is necessary to recognize that there is the potential for hypothermia after surgery via the lamina terminalis and third ventricle, even though the mechanisms of hypothalamic thermoregulation are still unclear.