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Yoko Hirata, Noriyuki Sakata, Tooru Inoue, Kotaro Yasumori, Masahiro Yasaka, and Yasushi Okada

Object

This study describes clinicopathological characteristics of pseudo-occlusion of the internal carotid artery with regard to its possible mechanisms.

Methods

The authors retrospectively reviewed 17 patients with pseudo-occlusion and 23 with high-grade stenosis (North American Symptomatic Carotid Endarterectomy Trial criteria ≥ 90%, but no collapsed distal internal carotid artery) who underwent carotid endarterectomy. Atherosclerotic risk factors, clinical presentation, angiographic findings, and histological features of plaque obtained from the carotid endarterectomy were investigated and comparisons were made between groups.

Results

Plaques obtained in the pseudo-occlusion group were significantly more fibrous and less atheromatous than those in the high-grade stenosis group. Old, organized thrombi were more frequently found in pseudo-occlusion group plaques than in high-grade stenosis group plaques. Plaques acquired in the pseudo-occlusion group had 2 different histological features: the presence or absence of the original lumen. The pseudo-occlusion plaques with total occlusion and recanalization (8 patients) were composed of thrombotic total occlusion with lumen recanalization by large neovascular channels, whereas those with severe stenosis (9 patients) were fibrous or fibroatheromatous and had severe stenosis of the original lumen. In patients with pseudo-occlusion and total occlusion and recanalization, the authors observed a significantly higher incidence of transient ischemic attack and anterior communicating artery–posterior communicating artery collateral flow than those with high-grade stenosis and pseudo-occlusion with severe stenosis.

Conclusions

Plaques of the pseudo-occlusion group were more fibrous than those of the high-grade stenosis group and had 2 different histological features: pseudo-occlusion with total occlusion and recanalization or pseudoocclusion with severe stenosis. This difference in plaque histology may be related to the clinical features of pseudoocclusion, such as symptoms and collateral flow patterns.

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Han Soo Chang, Masahiro Joko, Joon Suk Song, Kiyoshi Ito, Tatsushi Inoue, and Hiroshi Nakagawa

✓Extradural unroofing of the optic canal and subsequent mobilization of the optic nerve is a useful technique in the surgical treatment of parasellar tumors; however, the drilling procedure itself is associated with the risk of optic nerve damage. A safer technique would certainly be beneficial. The ultrasonic bone curette is a device developed in Japan for safer bone removal. Its use in intradural anterior clinoidectomy and opening of the internal auditory meatus has been reported before. In this article the authors describe their experience in using this device for extradural unroofing of the optic canal in patients with parasellar tumors.

Between March 2002 and November 2004, the aforementioned technique was used in the treatment of eight patients with parasellar tumors. After undertaking a frontotemporal craniotomy and orbital osteotomy, an ultrasonic bone curette was used to unroof the optic canal via an epidural approach; in five cases anterior clinoidectomy was added subsequently.

Using an ultrasonic bone curette, unroofing of the optic canal was completed safely and required much less expertise than that required for standard drilling. The mortality and major morbidity rates were 0%. The visual function outcome was satisfactory, with the overall visual status improving in all seven patients in whom this symptom was present preoperatively. The ultrasonic bone curette makes the unroofing of the optic canal safer and easier, possibly improving the visual outcome of patients undergoing surgery for parasellar tumors.

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Toshifumi Shimada, Kazunori Toyoda, Tooru Inoue, Masahiro Kamouchi, Takahiro Matsumoto, Koji Hiyamuta, Tsutomu Imaizumi, and Yasushi Okada

Object. The authors determined the factors that predict the coexistence of coronary artery disease (CAD) in patients who undergo carotid endarterectomy (CEA).

Methods. Data from 200 consecutive Japanese patients who underwent CEA for extracranial carotid artery stenosis were studied. Among 73 patients with CAD, 35 (48%) had three-vessel or left main CAD (that is, severe CAD). Peripheral artery disease was an independent predictor of CAD (odds ratio [OR] 2.61, 95% confidence interval [CI] 1.08–6.3). In addition, diabetes mellitus ([DM]; OR 2.8, 95% CI 1.24–6.32) and peripheral artery disease (PAD) (OR 2.83, 95% CI 1.05–7.57) were independent predictors of severe CAD in the 200 patients. The percentage of patients with CAD as well as those with the severe form of the disease increased stepwise as the number of major coronary risk factors in patients increased. Asymptomatic CAD was newly detected during the pre-CEA assessment in 18 (25%) of the 73 patients in whom CAD was eventually diagnosed. Diabetes mellitus was an independent predictor of occult CAD among the 200 patients (OR 4.83, 95% CI 1.53–15.2).

Conclusions. In patients with DM, PAD, or multiple major coronary risk factors who have been scheduled for CEA, one should carefully search for concomitant CAD, especially severe CAD, even when the patient has had no previous episode of angina.

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Ayato Hayashi, Masanobu Nishida, Hisakazu Seno, Masahiro Inoue, Hiroshi Iwata, Tomohiro Shirasawa, Hajime Arai, Ryoji Kayamori, Yuzo Komuro, and Akira Yanai

Object

The authors have developed a technique for the treatment of facial paralysis that utilizes anastomosis of the split hypoglossal and facial nerve. Here, they document improvements in the procedure and experimental evidence supporting the approach.

Methods

They analyzed outcomes in 36 patients who underwent the procedure, all of whom had suffered from facial paralysis following the removal of large vestibular schwannomas. The average period of paralysis was 6.2 months. The authors used 5 different variations of a procedure for selecting the split nerve, including evaluation of the split nerve using recordings of evoked potentials in the tongue.

Results

Successful facial reanimation was achieved in 16 of 17 patients using the cephalad side of the split hypoglossal nerve and in 15 of 15 patients using the caudal side. The single unsuccessful case using the cephalad side of the split nerve resulted from severe infection of the cheek. Procedures using the ansa cervicalis branch yielded poor success rates (2 of 4 cases).

Some tongue atrophy was observed in all variants of the procedure, with 17 cases of minimal atrophy and 14 cases of moderate atrophy. No procedure led to severe atrophy causing functional deficits of the tongue.

Conclusions

The split hypoglossal-facial nerve anastomosis procedure consistently leads to good facial reanimation, and the use of either half of the split hypoglossal nerve results in facial reanimation and moderate tongue atrophy.

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Satoshi Suehiro, Takanori Ohnishi, Daisuke Yamashita, Shohei Kohno, Akihiro Inoue, Masahiro Nishikawa, Shiro Ohue, Junya Tanaka, and Takeharu Kunieda

OBJECTIVE

High invasiveness of malignant gliomas frequently causes early local recurrence of the tumor, resulting in extremely poor outcome. To control such recurrence, novel therapies targeted toward infiltrating glioma cells around the tumor border are required. Here, the authors investigated the antitumor activity of sonodynamic therapy (SDT) combined with a sonosensitizer, 5-aminolevulinic acid (5-ALA), on malignant gliomas to explore the possibility for clinical use of 5-ALA–mediated SDT (5-ALA-SDT).

METHODS

In vitro cytotoxicity of 5-ALA-SDT was evaluated in U87 and U251 glioma cells and in U251Oct-3/4 glioma stemlike cells. Treatment-related apoptosis was analyzed using flow cytometry and TUNEL staining. Intracellular reactive oxygen species (ROS) were measured and the role of ROS in treatment-related cytotoxicity was examined by analysis of the effect of pretreatment with the radical scavenger edaravone. Effects of 5-ALA-SDT with high-intensity focused ultrasound (HIFU) on tumor growth, survival of glioma-transplanted mice, and histological features of the mouse brains were investigated.

RESULTS

The 5-ALA-SDT inhibited cell growth and changed cell morphology, inducing cell shrinkage, vacuolization, and swelling. Flow cytometric analysis and TUNEL staining indicated that 5-ALA-SDT induced apoptotic cell death in all gliomas. The 5-ALA-SDT generated significantly higher ROS than in the control group, and inhibition of ROS generation by edaravone completely eliminated the cytotoxic effects of 5-ALA-SDT. In the in vivo study, 5-ALA-SDT with HIFU greatly prolonged survival of the tumor-bearing mice compared with that of the control group (p < 0.05). Histologically, 5-ALA-SDT produced mainly necrosis of the tumor tissue in the focus area and induced apoptosis of the tumor cells in the perifocus area around the target of the HIFU-irradiated field. The proliferative activity of the entire tumor was markedly decreased. Normal brain tissues around the ultrasonic irradiation field of HIFU remained intact.

CONCLUSIONS

The 5-ALA-SDT was cytotoxic toward malignant gliomas. Generation of ROS by the SDT was thought to promote apoptosis of glioma cells. The 5-ALA-SDT with HIFU induced tumor necrosis in the focus area and apoptosis in the perifocus area of the HIFU-irradiated field, whereas the surrounding brain tissue remained normal, resulting in longer survival of the HIFU-treated mice compared with that of untreated mice. These results suggest that 5-ALA-SDT with HIFU may present a less invasive and tumor-specific therapy, not only for a tumor mass but also for infiltrating tumor cells in malignant gliomas.

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Shiho Nakano, Masahiro Inoue, Hiroshi Takahashi, Go Kubota, Junya Saito, Masaki Norimoto, Keita Koyama, Atsuya Watanabe, Takayuki Nakajima, Yusuke Sato, Shuhei Ohyama, Sumihisa Orita, Yawara Eguchi, Kazuhide Inage, Yasuhiro Shiga, Masato Sonobe, Arata Nakajima, Seiji Ohtori, Koichi Nakagawa, and Yasuchika Aoki

OBJECTIVE

The authors sought to evaluate the relationship between the difference in lumbar lordosis (DiLL) in the preoperative supine and standing positions and spinal sagittal alignment in patients with lumbar spinal stenosis (LSS) and to determine whether this difference affects the clinical outcome of laminectomy.

METHODS

Sixty patients who underwent single-level unilateral laminectomy for bilateral decompression of LSS were evaluated. Spinopelvic parameters in the supine and standing positions were measured preoperatively and at 3 months and 2 years postoperatively. DiLL between the supine and standing positions was determined as follows: DiLL = supine LL − standing LL. On the basis of this determination patients were then categorized into DiLL(+) and DiLL(−) groups. The relationship between DiLL and preoperative spinopelvic parameters was evaluated using Pearson’s correlation coefficient. In addition, clinical outcomes such as visual analog scale (VAS) and Oswestry Disability Index (ODI) scores between the two groups were measured, and their relationship to DiLL was evaluated using two-group comparison and multivariate analysis.

RESULTS

There were 31 patients in the DiLL(+) group and 29 in the DiLL(−) group. DiLL was not associated with supine LL but was strongly correlated with standing LL and pelvic incidence (PI) − LL (PI − LL). In the preoperative spinopelvic alignment, LL and SS in the standing position were significantly smaller in the DiLL(+) group than in the DiLL(−) group, and PI − LL was significantly higher in the DiLL(+) group than in the DiLL(−) group. There was no difference in the clinical outcomes 3 months postoperatively, but low-back pain, especially in the sitting position, was significantly higher in the DiLL(+) group 2 years postoperatively. DiLL was associated with low-back pain in the sitting position, which was likely to persist in the DiLL(+) group postoperatively.

CONCLUSIONS

We evaluated the relationship between DiLL and spinal sagittal alignment and the influence of DiLL on postoperative outcomes in patients with LSS. DiLL was strongly correlated with PI − LL, and in the DiLL(+) group, postoperative low-back pain relapsed. DiLL can be useful as a new spinal alignment evaluation method that supports the conventional spinal sagittal alignment evaluation.