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Kyohei Kin, Takao Yasuhara, Yousuke Tomita, Michiari Umakoshi, Jun Morimoto, and Isao Date

OBJECTIVE

Cervical spondylotic myelopathy (CSM) is one of the most common causes of spinal cord dysfunction. Surgery for CSM is generally effective, but postoperative delirium is a potential complication. Although there have been some studies that investigated postoperative delirium after spine surgery, no useful tool for identifying high-risk patients has been established, and it is unknown if 36-Item Short Form Health Survey (SF-36) scores can predict postoperative delirium. The objective of this study was to evaluate the correlation between preoperative SF-36 scores and postoperative delirium after surgery for CSM.

METHODS

Sixty-seven patients who underwent surgery for CSM at the authors’ institution were enrolled in this study. Medical records of these patients were retrospectively reviewed. Patient background, preoperative laboratory data, preoperative SF-36 scores, the preoperative Japanese Orthopaedic Association (JOA) score for the evaluation of cervical myelopathy, and perioperative factors were selected as potential risk factors for postoperative delirium. These factors were evaluated using univariable and multivariable logistic regression analysis.

RESULTS

Ten patients were diagnosed with postoperative delirium. Univariable analysis revealed that the physical functioning score (p = 0.01), general health perception score (p < 0.01), and vitality score (p < 0.01) of the SF-36 were significantly lower in patients with postoperative delirium than in those without. The total number of medications was significantly higher in the delirium group compared with the no-delirium group (p = 0.02). In contrast, there were no significant differences between the delirium group and the no-delirium group in cervical JOA scores (p = 0.20). Multivariable analysis revealed that a low general health perception score was an independent risk factor for postoperative delirium (p = 0.02; odds ratio 0.810, 95% confidence interval 0.684–0.960).

CONCLUSIONS

Some of the SF-36 scores were significantly lower in patients with postoperative delirium than in those without. In particular, the general health perception score was independently correlated with postoperative delirium. SF-36 scores could help identify patients at high risk for postoperative delirium and aid in the development of prevention strategies.

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Takao Yasuhara, Takashi Tamiya, Kenji Sugiu, Satoshi Inoue, and Takashi Ohmoto

✓ The authors describe a case of de novo formation and rupture of an aneurysm located at the junction of the left internal carotid artery and the superior hypophyseal artery in a middle-aged woman 2 months after another aneurysm, located on the anterior communicating artery, had been clipped. This case is rare because of the short interval between the last angiographic study performed at the first operation and the diagnosis of the de novo aneurysm; in this case the interval was only 47 days, compared with other cases in the literature in which the intervals were 3 to 34 years. Aneurysms can enlarge considerably in 2 to 4 weeks and can rupture at or soon after their formation. This case provides insight into aneurysm formation and rupture.

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Takao Yasuhara, Toru Fukuhara, Minoru Nakagawa, Yoshinori Terai, Kimihiro Yoshino, Koichi Mizobuchi, and Shunichiro Fujimoto

✓ The authors describe a unique presentation of Wegener granulomatosis (WG) manifesting predominantly as meningitis. Magnetic resonance imaging demonstrated diffuse meningeal enhancement, including the pia mater, in a 28-yearold man with meningitis. A diagnosis of atypical WG was based on the findings of a dural biopsy sample and an elevated cytoplasmic antineutrophil cytoplasmic antibody (cANCA) titer, although the patient did not have any of the lesions common to WG. Immunosuppressive therapy was quite effective. With treatment, the meningeal enhancement resolved and the cANCA titer normalized. Meningeal granulomatosis as the sole lesion in WG has never been reported in the literature. This atypical course of WG should be noted.

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Kenichiro Muraoka, Tetsuro Shingo, Takao Yasuhara, Masahiro Kameda, Wen Ji Yuen, Takashi Uozumi, Toshihiro Matsui, Yasuyuki Miyoshi, and Isao Date

Object

The therapeutic effects of adult and embryonic neural precursor cells (NPCs) were evaluated and their therapeutic potential compared in a rat model of Parkinson disease.

Methods

Adult NPCs were obtained from the subventricular zone and embryonic NPCs were taken from the ganglionic eminence of 14-day-old embryos. Each NPC type was cultured with epidermal growth factor. The in vitro neuronal differentiation rate of adult NPCs was approximately equivalent to that of embryonic NPCs after two passages. Next, the NPCs were transfected with either green fluorescent protein or glial cell line–derived neurotrophic factor (GDNF) by adenoviral infection and transplanted into the striata in a rat model of Parkinson disease (PD) induced by unilateral intrastriatal injection of 6-hydroxydopamine. An amphetamine-induced rotation test was used to evaluate rat behavioral improvement, and immunohistochemical analysis was performed to compare grafted cell survival, differentiation, and host tissue changes.

Results

The rats with GDNF-transfected NPCs had significantly fewer amphetamine-induced rotations and less histological damage. Except for the proportion of surviving grafted cells, there were no significant differences between adult and embryonic NPCs.

Conclusions

Adult and embryonic NPCs have a comparable therapeutic potential in a rat model of PD.

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Reiichiro Tanaka, Tetsuya Yumoto, Naoki Shiba, Motohisa Okawa, Takao Yasuhara, Tomotsugu Ichikawa, Koji Tokunaga, Isao Date, and Yoshihito Ujike

Magnetic resonance imaging is used with increasing frequency to provide accurate clinical information in cases of acute brain injury, and it is important to ensure that intracranial pressure (ICP) monitoring devices are both safe and accurate inside the MRI suite. A rare case of thermal brain injury during MRI associated with an overheated ICP transducer is reported.

This 20-year-old man had sustained a severe contusion of the right temporal and parietal lobes during a motor vehicle accident. An MR-compatible ICP transducer was placed in the left frontal lobe. The patient was treated with therapeutic hypothermia, barbiturate therapy, partial right temporal lobectomy, and decompressive craniectomy. Immediately after MRI examination on hospital Day 6, the ICP monitor was found to have stopped working, and the transducer was subsequently removed. The patient developed meningitis after this event, and repeat MRI revealed additional brain injury deep in the white matter on the left side, at the location of the ICP transducer. It is suspected that this new injury was caused by heating due to the radiofrequency radiation used in MRI because it was ascertained that the tip of the transducer had been melted and scorched. Scanning conditions—including configuration of the transducer, MRI parameters such as the type of radiofrequency coil, and the specific absorption rate limit—deviated from the manufacturer's recommendations. In cooperation with the manufacturer, the authors developed a precautionary tag describing guidelines for safe MR scanning to attach to the display unit of the product.

Strict adherence to the manufacturer's guidelines is very important for preventing serious complications in patients with ICP monitors undergoing MRI examinations.

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Takao Yasuhara, Tetsuro Shingo, Kenichiro Muraoka, Kazuki Kobayashi, Akira Takeuchi, Akimasa Yano, Yuan WenJi, Masahiro Kameda, Toshihiro Matsui, Yasuyuki Miyoshi, and Isao Date

Object. Glial cell line—derived neurotrophic factor (GDNF) has been shown to confer neuroprotective effects on dopaminergic neurons. The authors investigated the effects of GDNF on 6-hydroxydopamine (6-OHDA)—treated dopaminergic neurons in vitro and in vivo.

Methods. First, the authors examined how 1, 10, or 100 ng/ml of GDNF, administered to cells 24 hours before, simultaneously with, or 2 or 4 hours after 6-OHDA was added, affected dopaminergic neurons. In a primary culture of E14 murine ventral mesencephalic neurons, earlier treatment with the higher dosage of GDNF suppressed 6-OHDA—induced loss of dopaminergic neurons better than later treatment. Next, the authors examined whether continuous infusion of GDNF at earlier time points would demonstrate a greater neuroprotective effect in a rat model of Parkinson disease (PD). They established a human GDNF-secreting cell line, called BHK-GDNF, and encapsulated the cells into hollow fibers. The encapsulated cells were unilaterally implanted into the striatum of adult rats 1 week before; simultaneously with; or 1, 2, or 4 weeks after 6-OHDA was given to induce lesions of the same striatum. With the earlier transplantation of a BHK-GDNF capsule, there was a significant reduction in the number of amphetamine-induced rotations displayed by the animals. Rats that had received earlier implantation of BHK-GDNF capsules displayed more tyrosine hydroxylase—positive neurons in the substantia nigra pars compacta and a tendency for glial proliferation in the striatum.

Conclusions. These neuroprotective effects may be related to glial proliferation and signaling via the GDNF receptor α1. The results of this study support a role for this grafting technique in the treatment of PD.

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Akimasa Yano, Tetsuro Shingo, Akira Takeuchi, Takao Yasuhara, Kazuki Kobayashi, Kazuya Takahashi, Kenichiro Muraoka, Toshihiro Matsui, Yasuyuki Miyoshi, Hirofumi Hamada, and Isao Date

Object

The authors evaluated the neuroprotective and angiogenic effects of a continuous and low-dose infusion of vascular endothelial growth factor (VEGF)-165 on cerebral ischemia in rats.

Methods

The authors introduced VEGF complementary (c)DNA into baby hamster kidney (BHK) cells and established a cell line that produces human VEGF165 (BHK-VEGF). The BHK-VEGF cells and BHK cells that had been transfected with an expression vector that did not contain human VEGF165 cDNA (BHK-control) were encapsulated. Both capsules were implanted into rat striata. Six days after capsule implantation, the right middle cerebral artery (MCA) was occluded. Some animals were killed 24 hours after occlusion to measure the volume of the resulting infarct and to perform immunohistochemical studies. Other animals were used for subsequent behavioral studies 1, 7, and 14 days after MCA occlusion.

The encapsulated BHK-VEGF cell grafts significantly reduced the volume of the infarct and the number of apoptotic cells in the penumbral area when compared with the effect of the BHK-control cell capsule. In addition, angiogenesis and gliogenesis significantly increased in the region around the capsule in animals that received BHK-VEGF cell capsules without an increase in focal cerebral blood flow; this did not occur in animals that received the BHK-control cell capsule. In behavioral studies rats that received the BHK-VEGF cell capsule displayed significant recovery while participating in the accelerating rotarod test after stroke.

Conclusions

Continuous intracerebral administration of low-dose VEGF165 through encapsulated grafts of VEGF-producing cells produces neuroprotective and angiogenic effects. These effects improve subsequent motor function.

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Keisuke Takai, Toshiki Endo, Takao Yasuhara, Toshitaka Seki, Kei Watanabe, Yuki Tanaka, Ryu Kurokawa, Hideaki Kanaya, Fumiaki Honda, Takashi Itabashi, Osamu Ishikawa, Hidetoshi Murata, Takahiro Tanaka, Yusuke Nishimura, Kaoru Eguchi, Toshihiro Takami, Yusuke Watanabe, Takeo Nishida, Masafumi Hiramatsu, Tatsuya Ohtonari, Satoshi Yamaguchi, Takafumi Mitsuhara, Seishi Matsui, Hisaaki Uchikado, Gohsuke Hattori, Nobutaka Horie, Hitoshi Yamahata, and Makoto Taniguchi

OBJECTIVE

Spinal arteriovenous shunts are rare vascular lesions and are classified into 4 types (types I–IV). Due to rapid advances in neuroimaging, spinal epidural AVFs (edAVFs), which are similar to type I spinal dural AVFs (dAVFs), have recently been increasingly reported. These 2 entities have several important differences that influence the treatment strategy selected. The purposes of the present study were to compare angiographic and clinical differences between edAVFs and dAVFs and to provide treatment strategies for edAVFs based on a multicenter cohort.

METHODS

A total of 280 consecutive patients with thoracic and lumbosacral spinal dural arteriovenous fistulas (dAVFs) and edAVFs with intradural venous drainage were collected from 19 centers. After angiographic and clinical comparisons, the treatment failure rate by procedure, risk factors for treatment failure, and neurological outcomes were statistically analyzed in edAVF cases.

RESULTS

Final diagnoses after an angiographic review included 199 dAVFs and 81 edAVFs. At individual centers, 29 patients (36%) with edAVFs were misdiagnosed with dAVFs. Spinal edAVFs were commonly fed by multiple feeding arteries (54%) shunted into a single or multiple intradural vein(s) (91% and 9%) through a dilated epidural venous plexus. Preoperative modified Rankin Scale (mRS) and Aminoff-Logue gait and micturition grades were worse in patients with edAVFs than in those with dAVFs. Among the microsurgical (n = 42), endovascular (n = 36), and combined (n = 3) treatment groups of edAVFs, the treatment failure rate was significantly higher in the index endovascular treatment group (7.5%, 31%, and 0%, respectively). Endovascular treatment was found to be associated with significantly higher odds of initial treatment failure (OR 5.72, 95% CI 1.45–22.6). In edAVFs, the independent risk factor for treatment failure after microsurgery was the number of intradural draining veins (OR 17.9, 95% CI 1.56–207), while that for treatment failure after the endovascular treatment was the number of feeders (OR 4.11, 95% CI 1.23–13.8). Postoperatively, mRS score and Aminoff-Logue gait and micturition grades significantly improved in edAVFs with a median follow-up of 31 months.

CONCLUSIONS

Spinal epidural AVFs with intradural venous drainage are a distinct entity and may be classified as type V spinal vascular malformations. Based on the largest multicenter cohort, this study showed that primary microsurgery was superior to endovascular treatment for initial treatment success in patients with spinal edAVFs.

Open access

Keisuke Takai, Toshiki Endo, Takao Yasuhara, Toshitaka Seki, Kei Watanabe, Yuki Tanaka, Ryu Kurokawa, Hideaki Kanaya, Fumiaki Honda, Takashi Itabashi, Osamu Ishikawa, Hidetoshi Murata, Takahiro Tanaka, Yusuke Nishimura, Kaoru Eguchi, Toshihiro Takami, Yusuke Watanabe, Takeo Nishida, Masafumi Hiramatsu, Tatsuya Ohtonari, Satoshi Yamaguchi, Takafumi Mitsuhara, Seishi Matsui, Hisaaki Uchikado, Gohsuke Hattori, Hitoshi Yamahata, and Makoto Taniguchi

OBJECTIVE

The purpose of the present study was to compare the treatment success rates of primary neurosurgical and endovascular treatments in patients with spinal dural arteriovenous fistulas (dAVFs).

METHODS

Data from 199 consecutive patients with thoracic and lumbosacral spinal dAVFs were collected from 18 centers. Angiographic and clinical findings, the rate of initial treatment failure or recurrence by procedures, risk factors for treatment failure, complications, and neurological outcomes were statistically analyzed.

RESULTS

Spinal dAVFs were frequently detected in the thoracic region (81%), fed by a single feeder (86%), and shunted into an intradural vein via the dura mater. The fistulous connection between the feeder(s) and intradural vein was located at a single spinal level in 195 patients (98%) and at 2 independent levels in 4 patients (2%). Among the neurosurgical (n = 145), and endovascular (n = 50) treatment groups of single dAVFs (n = 195), the rate of initial treatment failure or recurrence was significantly higher in the index endovascular treatment group (0.68% and 36%). A multivariate analysis identified endovascular treatment as an independent risk factor with significantly higher odds of initial treatment failure or recurrence (OR 69; 95% CI 8.7–546). The rate of complications did not significantly differ between the two treatment groups (4.1% for neurosurgical vs 4.0% for endovascular treatment). With a median follow-up of 26 months, improvements of ≥ 1 point in the modified Rankin Scale (mRS) score and Aminoff-Logue gait and Aminoff-Logue micturition grades were observed in 111 (56%), 121 (61%), and 79 (40%) patients, respectively. Independent risk factors for lack of improvement in the Aminoff-Logue gait grades were multiple treatments due to initial treatment failure or recurrence (OR 3.1) and symptom duration (OR 1.02).

CONCLUSIONS

Based on data obtained from the largest and most recently assessed multicenter cohort, the present study shows that primary neurosurgery is superior to endovascular treatment for the complete obliteration of spinal dAVFs by a single procedure.