Shoichiro Kawaguchi

Effect of carotid endarterectomy on chronic ocular ischemic syndrome due to internal carotid artery stenosis.

OBJECTIVEWe evaluated the effect of carotid endarterectomy on chronic ocular ischemic syndrome due to internal carotid artery stenosis by use of data obtained from ophthalmic artery color Doppler flow imaging. METHODSWe examined 11 patients with ocular ischemic syndrome due to internal carotid artery stenosis (>70% stenosis) who were being treated by carotid endarterectomy. Ophthalmic artery color Doppler flow imaging indicated ophthalmic artery flow direction and peak systolic flow velocity and was performed before and at 1 week, 1 month, and 3 months after surgery. RESULTSWe assessed the ophthalmic arteries of 11 patients via color Doppler flow imaging. Before undergoing carotid endarterectomy, five patients showed reversed ophthalmic artery flow. In the other six patients who experienced antegrade ophthalmic artery flow, the average peak systolic flow velocity was 0.09 ± 0.05 m/s (mean ± standard deviation). Preoperative reversed flow resolved in each patient 1 week after undergoing surgery. All patients showed antegrade ophthalmic artery flow. The average peak systolic flow velocity in the patients who had preoperative antegrade flow rose significantly, to 0.21 ± 0.14 m/s (P < 0.05). There was no significant change as compared with findings at 1 week after surgery. During the follow-up period (mean, 32.4 mo), no patients complained of recurrent visual symptoms. At the end of the study period, visual acuity had improved in five patients and had not worsened in the other six patients. CONCLUSIONCarotid endarterectomy was effective for improving or preventing the progress of chronic ocular ischemia caused by internal carotid artery stenosis.

Transplantation of embryonic stem cell-derived neural stem cells for spinal cord injury in adult mice

Abstract Aims: To investigate the efficacy of embryonic stem cell-derived neural stem cells (NSCs) for spinal cord injury (SCI) in mice and whether a combination treatment with thyroid hormone provides a more effective ES cell-based therapy. Methods: Nestin-positive NSCs were induced from undifferentiated mouse ES cells by a step-by-step culture and used as grafts. Thirty-six mice were subjected to an SCI at Th10 and divided into three groups of 12. Graft cells were transplanted into the injury site 10 days after injury. Group 1 mice were left under observation without receiving graft cells, while mice in Group 2 received 2 × 104 graft cells, and those in Group 3 received 2 × 104 graft cells and were treated with a continuous intraperitoneal injection of thyroxin using osmotic mini-pumps. Behavioral improvement was assessed by a scoring system throughout the experimental period until post-transplantation day (PD) 28. Results: Mice in Groups 2 and 3 demonstrated an improved behavioral function, as compared to those in Group 1 after PD 14. There was no significant difference in behavioral recovery between Groups 2 and 3. Conclusions: Transplantation of ES-NSCs into the injury site was effective for SCI, while thyroxine did not deliver additional effectiveness.

Effect of Carotid Artery Stenting on Ocular Circulation and Chronic Ocular Ischemic Syndrome

Background: The authors evaluated the effect of carotid artery stenting (CAS) on ocular circulation and chronic ocular ischemic syndrome. Methods: We examined 38 patients with carotid artery stenosis (>80%) at its origin treated with CAS. Ocular circulation and symptoms were examined before, within 24 h, and 1 week, 1 month, and 3 months after CAS based on ophthalmic artery color Doppler flow imaging and ophthalmological examinations. Results: Ocular circulation: Before CAS, 13 patients showed reversed ophthalmic artery flow, and 25 antegrade flow. Average peak systolic flow velocity was –0.038 m/s. Within 24 h after CAS, all patients showed antegrade ophthalmic artery flow; reversed flow before CAS was thus resolved. Average peak systolic flow velocity rose significantly to 0.36 m/s (p < 0.05). One week, 1 month and 3 months after CAS, there were no significant changes compared to the findings at 1 week after CAS. Ocular symptoms: Before CAS, 8 patients showed chronic ocular ischemic syndrome. During the follow-up period (mean: 2.8 years), the visual acuity improved in 7 cases. Average retinal artery pressure and arm-to-retina circulation time improved significantly to the normal level (p < 0.05). The other 30 patients complained of recurrent and worsened visual symptoms during the follow-up period. Conclusion: CAS was effective in improving ocular circulation, and also improved the chronic ocular ischemic syndrome caused by the severe carotid artery stenosis.

Significance of the Hemorrhagic Site for Recurrent Bleeding: Prespecified Analysis in the Japan Adult Moyamoya Trial

Background and Purpose— The primary results of the Japan Adult Moyamoya Trial revealed the statistically marginal superiority of bypass surgery over medical treatment alone in preventing rebleeding in moyamoya disease. The purpose of this analysis is to test the prespecified subgroup hypothesis that the natural course and surgical effects vary depending on the hemorrhagic site at onset. Methods— The hemorrhagic site, classified as either anterior or posterior, was the only stratifying variable for randomization. Statistical analyses were focused on the assessment of effect modification according to the hemorrhagic site and were based on tests of interaction. Results— Of 42 surgically treated patients, 24 were classified as anterior hemorrhage and 18 as posterior hemorrhage; of 38 medically treated patients, 21 were classified as anterior and 17 as posterior. The hazard ratio of the primary end points (all adverse events) for the surgical group relative to the nonsurgical group was 0.07 (95% confidence interval, 0.01–0.55) for the posterior group, as compared with 1.62 (95% confidence interval, 0.39–6.79) for the anterior group (P=0.013 for interaction). Analysis within the nonsurgical group revealed that the incidence of the primary end point was significantly higher in the posterior group than in the anterior group (17.1% per year versus 3.0% per year; hazard ratio, 5.83; 95% confidence interval, 1.60–21.27). Conclusions— Careful interpretation of the results suggests that patients with posterior hemorrhage are at higher risk of rebleeding and accrue greater benefit from surgery, subject to verification in further studies. Clinical Trial Registration— URL: http://www.umin.ac.jp/ctr/index.htm. Unique identifier: C000000166.

Cervical myelopathy due to dynamic compression by the laminectomy membrane: dynamic MR imaging study.

Dynamic magnetic resonance (MR) imaging is useful in assessing delayed neurologic deterioration after multilevel cervical laminectomy. The authors report a case of a 75-year-old woman who deteriorated 24 years after a C4-C7 laminectomy. When the extension MR demonstrated marked spinal cord compression attributable to a laminectomy membrane, the patient had an anterior diskectomy and fusion performed, after which she demonstrated significant neurologic improvement. In this and other cases, the dynamic MR may be a useful tool in discerning the etiology of the delayed neurologic changes occurring in postoperative patients.

Giant frontal mucocele extending into the anterior cranial fossa.

The authors report a patient with a huge frontal mucocele presenting with transient left hemiparesis. Magnetic resonance imaging and computed tomography showed the huge frontal mucocele arising from the frontal sinus extending to the anterior cranial fo ssa. Right middle cerebral artery stenosis was seen on the carotid angiography. The mucocele was treated with Killians surgery. On the postoperative seventh day, the patient showed massive cerebrospinal fluid leakage that ceased with conservative management. The patient was discharged from the hospital without any neurological deficit. We discuss the clinical symptoms and postoperative course of the huge frontal mucocele with intracranial extension.

Surgery for dural arteriovenous fistula in superior sagittal sinus and transverse sigmoid sinus

The aim of this study was to evaluate the outcome of surgically treated dural arteriovenous fistula (DAVF). The authors performed surgical removal of DAVF in 12 patients. The locations of DAVF were the transverse sigmoid sinus in seven patients and superior sagittal sinus in five patients. These 12 patients had undergone endovascular embolisation prior to removal. Among them, six patients were completely cured, according to angiography immediately after embolisation, but these six patients showed the recurrence of DAVF within 1 year. The other six patients showed a decrease of feeding vessels. Therefore, all 12 patients underwent surgical removal of DAVF. The surgical strategies were as follows. The feeding vessels and the cortical veins with retrograde filling were occluded and cut. The affected sinus was skeletonised, and if it was occluded or almost occluded, the sinus was removed. Postoperatively, transient aphasia was seen in one patient. There was no surgical morbidity or mortality. During the follow-up period (mean 2.9 years), no recurrence of DAVF was seen. Surgical treatment is a safe and effective treatment manoeuvre for DAVF around the transverse sigmoid sinus and superior sagittal sinus.

Effects of bypass on ocular ischaemic syndrome caused by reversed flow in the ophthalmic artery.

Superficial temporal to middle cerebral artery bypass was useful for ocular ischaemic syndrome caused by reversed flow in the ophthalmic artery as shown by ophthalmic-artery colour doppler flow imaging.

Color Doppler Flow Imaging of the Superior Ophthalmic Vein in Dural Arteriovenous Fistulas

Background and Purpose— This article evaluates the intracranial venous hemodynamics of dural arteriovenous fistula (DAVF) on the basis of data from color Doppler flow imaging (CDFI) findings of the superior ophthalmic vein (SOV) and discusses the clinical application of the SOV CDFI to the DAVFs. Methods— We examined the diameter, flow direction, flow waveform, and flow velocity of the SOV using CDFI in 20 patients with intracranial DAVF. Six patients were asymptomatic; the other 14 patients were symptomatic. Angiographic retrograde cortical venous filling was seen in 14 patients. Results— In the DAVFs, the average SOV diameter was 2.95±1.15 mm, which was significantly broad compared with that of the control subjects (P <0.05). The flow direction was reversed in 2 patients and normal in the other 18 patients. Three patients showed an abnormal waveform. A reversed pulsatile waveform was observed in 2 patients, and a normograde pulsatile waveform was seen in 1 patient. The other 17 patients showed normal waveform. The average SOV diameter and resistance index values were significantly higher (P <0.05) in patients with clinical symptoms, angiographic retrograde cortical venous fillings, or large DAVFs compared with those in the other patients. Conclusions— The SOV CDFI findings in DAVFs correlated well with the patient’s clinical symptoms, angiographic findings, and DAVF size. These findings were useful to evaluate the intracranial venous hemodynamics in DAVFs.

Ocular Circulation and Chronic Ocular Ischemic Syndrome before and after Carotid Artery Revascularization Surgery.

Background. We evaluated the effect of carotid revascularization surgery on ocular circulation and chronic ocular ischemic syndrome (OIS). Methods. We examined ninety patients with carotid artery stenosis (more than 50% stenosis) at its origin treated with carotid endarterectomy (N = 56) or carotid artery stenting (N = 34). Twenty-five patients (28%) complained of chronic OIS. Ocular circulation was examined before and after revascularization surgery using ophthalmic artery (OphAr) and central retinal artery (CRA) color Doppler flow imaging. Results. (1) Ocular circulation: preoperatively, the average OphAr peak systolic flow velocity (Vs) was 0.05 m/sec, and the average CRA Vs was 0.07 m/sec. At 1 week after surgery, the average OphAr Vs significantly increased to 0.32 (P < 0.05), and the average CRA Vs significantly increased to 0.11 m/sec (P < 0.05). These significant improvements were sustained throughout the three months of the followup. (2) OIS: during the follow-up period (mean: 3.6 years), 15 patients (60%) showed visual acuity improvement, and no patients complained of amaurosis fugax or worsening of the chronic OIS. Conclusion. Carotid revascularization surgery was effective in improving the ocular circulation, and it was also useful for the chronic OIS due to the carotid artery stenosis.