Satoshi Ushikoshi

Treatment outcome of single or hypofractionated single-isocentric stereotactic irradiation (STI) using a linear accelerator for intracranial arteriovenous malformation

BACKGROUND AND PURPOSE We investigated the use of hypofractionated stereotactic radiotherapy (HFSR) to reduce adverse radiation effects in comparison to single-fraction stereotactic radiosurgery (SRS) for intracranial arteriovenous malformations (AVMs). MATERIALS AND METHODS This study includes 53 intracranial AVMs treated between 1991-1998. HFSR was selected for 26 AVMs with a maximum diameter > or 2.5 cm or at eloquent area. Twenty-seven patients were treated with SRS (18 AVMs < 2.5 cm at non-eloquent area, nine patients who were unfit for prolonged ring-wearing). The most frequent minimum dose (Dmin) was 20 Gy for SRS and 28 Gy for HFSR in four fractions. The mean follow-up duration was 34.6 months for SRS and 35.4 months for HFSR. RESULTS As a whole, the 3 and 5-year actuarial obliteration rates were 64 and 92%. Age <20 years old (P=0.02) and a maximum diameter <2 cm were favorable factors (P=0.05). A difference in the distribution of patients was observed in size (> or =2.5 cm or not) (P<0.001) and location (eloquent or not) (P<0.001) between SRS and HFSR due to the treatment selection. However, no significant differences were observed in the actuarial rates of obliteration and transient increased signals with T2-weighted MR images between SRS and HFSR. Radiation necrosis occurred in two patients treated with SRS and in none with HFSR. Intracranial hemorrhage after treatment happened in two treated with SRS and three with HFSR. CONCLUSIONS HFSR appears to be at least as effective as SRS in achieving complete obliteration of intracranial AVM, although its definitive role remains to be investigated.

Does Intensive Management of Cerebral Hemodynamics and Atheromatous Aorta Reduce Stroke After Coronary Artery Surgery

BACKGROUND Atheromatous aorta and carotid artery disease are known predictors for stroke after coronary artery bypass grafting (CABG). The clinical significance of intracranial cerebral artery disease is not known. This study was designed to determine whether a therapeutic strategy based on perioperative detection of intracranial and extracranial occlusive cerebrovascular disease and atheromatous aorta could reduce perioperative stroke. METHODS We studied 485 patients who underwent isolated CABG. The control group was 247 patients who underwent standard-protocol CABG. The 238 subjects in the intervention group underwent preoperative magnetic resonance angiography of the head and neck and intraoperative epiaortic scanning. Cerebral hemodynamics were evaluated by single photon emission computed tomography and acetazolamide tests in patients with significant occlusive cerebrovascular disease. Surgical outcomes were compared. RESULTS In the intervention group, magnetic resonance angiography detected significant intracranial or extracranial occlusive cerebrovascular disease, or both, in 40 patients. Prophylactic cerebrovascular interventions were performed in 7 patients who had disturbed cerebral hemodynamics. Aorta no-touch off-pump coronary artery bypass (OPCAB) was chosen intraoperatively in 37 patients with moderate to severe atheromatous aorta. The in-hospital stroke rate was 0.42% in the intervention group vs 2.8% in the control group (p = .068). A multivariate analysis revealed that the perioperative interventional protocol was the most powerful predictor of reduced risk of perioperative stroke (odds ratio, 0.023; 95% confidence interval, 0.001 to 0.469). CONCLUSIONS Prophylactic cerebrovascular interventions and the selective use of aorta no-touch OPCAB can significantly reduce the incidence of perioperative stroke. Careful vascular evaluation before and during CABG can improve surgical outcomes.

Rapid superselective high-dose cisplatin infusion with concomitant radiotherapy for advanced head and neck cancer

The purpose of this study was to evaluate the efficacy of rapid superselective high‐dose cisplatin infusion with concomitant radiotherapy for previously untreated patients with advanced head and neck cancer.

Surgical treatment of intracranial dural arteriovenous fistulas

BACKGROUND When considering the treatment strategies for dural arteriovenous fistulas (DAVFs), it is important to clarify the exact location of the fistula and venous drainage route from both DAVFs and normal brain tissue. DAVFs with leptomeningeal retrograde venous drainage carry a high risk of neurological deficits and require aggressive treatment. When AVFs involve the dural sinus, transvenous embolization via the transfemoral approach is usually the first choice of treatment. For DAVFs draining directly into the cortical veins without dural sinus involvement, transarterial embolization may be a curative treatment. However, when embolization is technically difficult or results in incomplete occlusion, surgical treatment is required. The purpose of the present study was to review our experience with surgical treatment of DAVFs. METHODS The present series included 17 patients; 9 had DAVFs involving the dural sinus with leptomeningeal retrograde venous drainage and 8 had DAVFs draining directly into the cortical veins. For DAVFs involving the sinus, embolization of the diseased sinus by direct surgical exposure was performed in 8 patients, and surgical excision in one. For DAVFs draining directly into the cortical veins, interruption of the draining veins close to DAVFs was undertaken in 7 and surgical excision in 1. RESULTS Complete obliteration of DAVFs was demonstrated in 16 patients. At final follow-up, 15 patients were asymptomatic and the other 2 showed clinical improvement. CONCLUSIONS For DAVFs involving the dural sinus, direct operative sinus packing is indicated. For DAVFs directly draining into the cortical veins, surgical interruption of the draining veins is indicated.

Vertebral arteriovenous fistula that developed in the same place as a previous ruptured aneurysm: a case report

BACKGROUND Aneurysms of the extracranial vertebral artery (VA) and vertebral arteriovenous fistulas (VAVFs) are relatively rare diseases. The most frequent cause of both diseases is trauma. Atraumatic lesions are less common. Presented here is a case of atraumatic AVF of the extracranial VA that developed in the same location as a previous ruptured aneurysm of the ipsilateral VA that was originally treated by proximal occlusion 11 years earlier. METHODS A 40-year-old woman presented with a massive hematoma in the upper posterior neck region caused by the rupture of an extracranial VA aneurysm. Proximal occlusion of the VA was performed by use of a detachable balloon. She enjoyed good health for 11 years, then she noticed a pulsatile bruit. Angiograms revealed an AVF between the left VA that was fed by collateral circulation and the paravertebral venous plexus. Incidentally found were soft tissue masses in the left retroauricular and the right suboccipital regions. Also, skull X-ray films showed multiple bony defects. Biopsy of the subcutaneous mass was performed in the hope of obtaining clues as to which pathological processes had weakened the artery. RESULTS As direct transarterial access to the fistula was out of the question, the fistulous compartment of the paravertebral venous plexus was tightly packed with multiple platinum coils effected by the transfemoral approach. A histological examination of the specimen revealed features of a neurofibroma, and a diagnosis of neurofibromatosis Type 1 was established. CONCLUSIONS In this case, transvenous embolization of the VAVF was successfully performed. The fragility of the arterial wall, related to neurofibromatosis Type 1, was considered to contribute to the development of the aneurysm and AVF.

Cerebral abscess as an unusual complication of coil embolization in a dural arteriovenous fistula: Case report

This 63-year-old man presented with a right temporoparietal cortical infarction. A dural arteriovenous fistula involving the right transverse sinus was diagnosed on cerebral angiography. Transvenous embolization using detachable coils was performed; however, postembolization angiograms demonstrated retrograde filling of a cortical draining vein that was not seen on initial angiography. The patient subsequently developed a cerebral abscess in the region of the previous cortical infarction 2 months after the embolization. The abscess was successfully treated with drainage and antibiotic therapy. The authors report this case to illustrate an unusual complication associated with this procedure and the possible contribution of the cortical draining vein in the pathogenesis of the cerebral abscess.

Pretreatment and Posttreatment Evaluation of Hemodynamic and Metabolic Parameters in Intracranial Dural Arteriovenous Fistulae with Cortical Venous Reflux

OBJECTIVERetrograde drainage into the cortical veins results in poor outcome in patients with an intracranial dural arteriovenous fistula. However, the pathophysiological features of dural arteriovenous fistulae remain obscure. This study aimed to clarify hemodynamic and metabolic conditions in these patients using positron emission tomography. METHODSThis study included eight patients with an intracranial dural arteriovenous fistula. All patients had cortical venous reflux, as demonstrated by angiography. Regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), regional cerebral metabolic rate for oxygen, and regional oxygen extraction fraction (rOEF) were measured before and after surgical or endovascular treatment using positron emission tomography. RESULTSPretreatment positron emission tomographic studies revealed that all patients had abnormal hemodynamic and metabolic parameters in the area that was drained by the involved cortical veins. A severe increase in rCBV was noted in seven of the eight patients. A significant decrease in rCBF also was observed in all eight patients. A negative correlation was observed between rCBF and rCBV. Three patients had an elevated rOEF. Oxygen metabolism was impaired in seven patients. All patients underwent successful treatment. Follow-up studies demonstrated significant improvements in rCBF, rCBV, and regional cerebral metabolic rate for oxygen. The improvement in regional cerebral metabolic rate for oxygen varied among the patients. Normalization of rOEF also was confirmed in three patients who had increased rOEF before the treatment. CONCLUSIONThe present results suggest that hemodynamic and metabolic characteristics vary widely among patients with cortical venous reflux. It is essential to precisely evaluate hemodynamic and metabolic conditions to predict their outcomes and therapeutic effects.

CT angiography with multidetector-row helical CT in spinal arteriovenous malformation

We performed intravenous CT angiography using multidetector-row helical computed tomography (MDCT) in a 63-year-old man with spinal arteriovenous malformation (AVM). The CT angiography demonstrated feeding arteries, varix-like structure, draining veins and their relationship to the spinal cord. Although selective angiography is essential in planning treatment for spinal AVMs as well as in establishing the diagnosis of the disease, CT angiography can be a good supplementary technique for visualizing precise location of abnormal vessels in a certain case of spinal AVM.

Spinal intrathecal actinomycosis: a case report

BACKGROUND Actinomycosis of the central nervous system is a rare disease that most frequently forms cerebral abscesses. In the present report, we describe an extremely rare case of spinal intrathecal actinomycosis. CASE PRESENTATION A 33-year-old man presented with high fever followed by back pain and paraparesis. Magnetic resonance imaging (MRI) with gadolinium-diethylene-triamine penta-acetic acid (Gd-DTPA) enhancement (Gd-MRI) displayed an irregularly enhanced mass lesion at the thoraco-lumbar junction that mimicked an intramedullary tumor with exophytic growth. Surgical exploration 7 months after the onset of the high fever revealed intrathecal granulation tissue with small abscess formation. Another surgical exploration was carried out 2 months after the first operation because the patient developed progressive paraparesis and showed an intrathecal ring-like enhancement that was detected with Gd-MRI. Actinomyces organisms were finally identified histologically in the surgical specimen. CONCLUSIONS The clinical course and serial changes of Gd-MRI findings are important considerations when this rare and infectious spinal lesion is suspected.

[Efficacy of Stent-Assisted Coil Embolization for a Dissecting Aneurysm of the Cervical Internal Carotid Artery Caused by a Systemic Vascular Disease: A Case Report].

Systemic vascular diseases such as fibromuscular dysplasia, Ehlers-Danlos syndrome, Marfan syndrome, and Behçets disease are known to cause spontaneous dissecting aneurysms of the cervical internal carotid artery. These diseases are generally associated with vascular fragility; therefore, invasive treatments are avoided in many cases of dissecting aneurysms, and a conservative approach is used for the primary disease. Surgical or intravascular treatment may be chosen when aneurysms are progressive or are associated with a high risk of hemorrhage; however, there is no consensus on which treatment is better. We report a case of a dissecting aneurysm of the cervical internal carotid artery in a patient with suspected Behçets disease, which was treated using stent-assisted coil embolization. A man in his 40s, with suspected Behçets disease, presented with an enlarged dissecting aneurysm of the right cervical internal carotid artery. The lesion was present for approximately 10 years. We performed stent-assisted coil embolization for the lesion. Post-surgery, no aneurysms were detected with carotid artery echography. Our case report suggests that stent-assisted coil embolization is a promising treatment for dissecting aneurysms of the cervical internal carotid artery. In addition, the procedure demonstrates the utility of carotid artery echograms for examining recanalization after stent-assisted coil embolization.