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Sadahiro Nomura, Shiro Kashiwagi, Hirosuke Fujisawa, Haruhide Ito and Kazuyuki Nakamura

✓ Fibrinogen, fibrin monomer, and D dimer were analyzed in 41 cases of chronic subdural hematoma (SDH) to characterize local rebleeding, coagulation, and fibrinolysis using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. Chronic SDH's were divided into five groups according to their appearance on computerized tomography: high-density, isodensity, low-density, mixed-density, and layering types. The concentration of fibrinogen, which indicates rebleeding, was higher in the mixed-density (15.7 ± 3.4 mg/dl (mean ± standard error of the mean)) and layering (15.7 ± 2.6 mg/dl) types of hematoma, and lower in the low-density hematomas (1.4 ± 0.6 mg/dl) compared with the isodense hematomas (6.9 ± 1.1 mg/dl). Fibrin monomer, which indicates coagulative activity, had a distribution similar to that of fibrinogen: 87 ± 22, 18 ± 8, 175 ± 40, and 177 ± 23 µg/ml in isodense, low and mixed-density, and layering types of hematomas, respectively. The D dimer, which indicates fibrinolytic activity, was higher in the layering hematoma type (2032 ± 384 µg/ml), and lower in low-density hematomas (301 ± 164 µg/ml) compared to isodense (1310 ± 256 µg/ml) and mixed-density (1039 ± 207 µg/ml) types of hematomas.

These observations suggest the following characterization of each type of chronic SDH. The layering type is active, with a high tendency to rebleed and for hyperfibrinolytic activity. The mixed-density type has a high tendency to rebleed with lower hyperfibrinolytic activity than the layering type. The low-density hematoma is stable with a low tendency to rebleed and to fibrinolytic activity.

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Hirokazu Sadahiro, Sadahiro Nomura, Hisaharu Goto, Kazutaka Sugimoto, Akinori Inamura, Yuichi Fujiyama, Akiko Yamane, Takayuki Oku, Mizuya Shinoyama and Michiyasu Suzuki

OBJECT

Endoscopic surgery plays a significant role in the treatment of intracerebral hemorrhage. However, the residual hematoma cannot be measured intraoperatively from the endoscopic view, and it is difficult to determine the precise location of the endoscope within the hematoma cavity. The authors attempted to develop real-time ultrasound-guided endoscopic surgery using a bur-hole-type probe.

METHODS

From November 2012 to March 2014, patients with hypertensive putaminal hemorrhage who underwent endoscopic hematoma removal were enrolled in this study. Real-time ultrasound guidance was performed with a bur-hole-type probe that was advanced via a second bur hole, which was placed in the temporal region. Ultrasound was used to guide insertion of the endoscope sheath as well as to provide information regarding the location of the hematoma during surgical evacuation. Finally, the cavity was irrigated with artificial cerebrospinal fluid and was observed as a low-echoic space, which facilitated detection of residual hematoma.

RESULTS

Ten patients with putaminal hemorrhage > 30 cm3 were included in this study. Their mean age (± SD) was 60.9 ± 8.6 years, and the mean preoperative hematoma volume was 65.2 ± 37.1 cm3. The mean percentage of hematoma that was evacuated was 96% ± 3%. None of the patients exhibited rebleeding after surgery.

CONCLUSIONS

This navigation method was effective in demonstrating both the real-time location of the endoscope and real-time viewing of the residual hematoma. Use of ultrasound guidance minimized the occurrence of brain injury due to hematoma evacuation.

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Sadahiro Nomura, Yoshiteru Kagawa, Hiroyuki Kida, Yuichi Maruta, Hirochika Imoto, Masami Fujii and Michiyasu Suzuki

Object

Cerebral palsy (CP) arises in the early stages of brain development and manifests as spastic paresis that is often associated with cognitive dysfunction. Available CP treatments are aimed at the management of spasticity and include botulinum toxin administration, selective dorsal rhizotomy, and intrathecal baclofen (ITB). In this study, the authors investigated whether the management of spasticity with ITB therapy affected motor function and whether the release of spasticity was associated with an improvement in intellectual function.

Methods

Newborn Sprague-Dawley rats were divided into the following groups: control, CP model, and CP model with ITB therapy. For the CP model, postnatal Day 7 (P7) rats were exposed to hypoxic conditions (8% O2) for 150 minutes after ligation of the right common carotid artery. In the groups receiving ITB therapy, a spinal catheter was connected to an osmotic pump filled with baclofen and placed in the spinal subarachnoid space on P21 in the early group and on P35 in the late group. A daily dose of 12 μg of baclofen was continuously administered until P49, resulting in 28 days of therapy in the early group and 14 days in the late group. Changes in spasticity in the CP and CP with ITB treatment groups were confirmed by assessing the motor evoked potential in the plantar muscle.

Results

In the CP group, the time required to complete a beam-walking test on P49 was significantly longer than that in the control and ITB treatment groups (4.15 ± 0.60 vs 2.10 ± 0.18 and 2.22 ± 0.22 seconds, respectively). Results of the beam-walking test are expressed as the mean ± SD. Radial arm maze performance on P49 indicated that spatial reference memory had significantly deteriorated in the CP group compared with controls (2.33 ± 0.87 vs 0.86 ± 0.90 points); moreover, working memory was also negatively affected by CP (0.78 ± 1.09 vs 0.14 ± 0.38 points). Results of the memory tests are expressed as the mean ± SE. These memory functions did not recover after ITB treatment.

Conclusions

Management of spasticity with ITB therapy improved the walking ability in the rat CP model. Intrathecal baclofen therapy—which reduces harmful sensory and motor stimulations caused by spasticity to more optimal levels—contributed to motor function recovery; however, it had no effect on intellectual recovery as assessed by memory performance in the rat CP model.

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Yoshihiko Maeda, Koichi Yoshikawa, Koji Kajiwara, Makoto Ideguchi, Takayuki Amano, Makoto Saka, Sadahiro Nomura, Masami Fujii and Michiyasu Suzuki

The authors report a rare case of intracranial yolk sac tumor in a 13-year-old boy with Down syndrome who presented with left hemiparesis. Admission MR imaging revealed a tumor in the right basal ganglia. Serum α-fetoprotein was markedly elevated. Yolk sac tumor was diagnosed radiologically and serologically. The standard therapy for intracranial yolk sac tumor is platinum-based chemotherapy with concomitant radiotherapy. However, the authors used reduced-dose chemotherapy and asynchronized radiotherapy because of the well-known low tolerance of patients with Down syndrome to chemotherapy. This treatment was successful with no complications. Blood cancers are frequently associated with Down syndrome, whereas solid tumors occur less frequently in these patients, and the risk of chemoradiotherapy is unclear. The results indicate that dose-reduction therapy can be effective for treatment of a brain tumor in a patient with Down syndrome.

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Yoshihiko Maeda, Sadahiro Nomura, Tetsu Kurokawa, Hideyuki Ishihara, Kei Harada, Hiroshi Yoneda, Shoichi Kato, Hirosuke Fujisawa and Michiyasu Suzuki

The authors report on the case of a girl with cerebrovascular moyamoya disease born with severe respiratory failure caused by a congenital diaphragmatic hernia. Cardiopulmonary management included extracorporeal membrane oxygenation until the diaphragm defect was repaired. The right common carotid artery (CA) was interrupted and cannulated for extracorporeal membrane oxygenation. When she was 5 years of age, the patient experienced ischemic symptoms in her right extremities. Angiography revealed stenosis of the terminal portion of the internal CA (ICA) with the development of moyamoya vessels on the left side of the brain; the right ICA was supplied by extracranial anastomotic arteries. Indirect extracranial–intracranial bypass surgery was performed in the left hemisphere, and the hypoperfusion improved. The same change in the intracranial ICA with the development of moyamoya vessels occurred on her right side when she was 7 years old. Decreased cerebral blood flow occurred twice, and the moyamoya vessels developed to compensate for the cerebral ischemia. However, the occlusion of the extracranial common CA in infancy induced extracranial anastomosis rather than moyamoya vessel proliferation, and collateral circulation was formed at the lesion site. This finding indicates that neoangiogenesis requires both cerebral ischemia and growth factors derived from the lesion.

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Shizuo Oi, Sadahiro Nomura, Masato Nagasaka, Hajime Arai, Reizo Shirane, Yasuo Yamanouchi, Hiroshi Nishimoto and Hiroaki Date

Object

The natural history of asymptomatic spinal lipoma in infancy remains unclear, and the indication for the prophylactic untethering operation is still debatable. To address this question, a multicenter cooperative study for the treatment of spinal lipoma was performed by the 7 most active institutions in neurosurgical care for spina bifida in Japan between 2001 and 2005.

Methods

Patients were classified using the embryopathogenetic surgicoanatomical classification. Their neurosurgical postoperative course was analyzed using the Spina Bifida Neurological Scale. Among 261 patients, 159 were asymptomatic and 102 were symptomatic.

Results

Of the 136 patients for whom prophylactic surgeries were performed, 135 remained asymptomatic and only 1 (0.4%) of the 261 patients presented with mild sensory disturbance. Mild foot deformity was identified in 1 (4.3%) of 23 conservatively observed patients. Of 100 symptomatic patients, deterioration after surgery was seen in 6%, and improvement in 44%. Complete resolution of symptoms was seen in only 14.2%. Filar types for patients > 3 years old improved in Spina Bifida Neurological Scale scores from 12.3 to 14.0. The mean age of symptomatic patients with lipomyelomeningocele was the youngest of all (1.3 years), which indicates lipomyelomeningocele may deteriorate in early infancy. Improvements from surgery were seen for all types of lipoma except the caudal type, presenting at an older mean age (15 years).

Conclusions

A low rate of postsurgical worsening indicates that surgeries for asymptomatic and symptomatic lipomas are safe. Surgeries done after the onset of symptoms seldom cure the patients. These two results support early untethering for any kind of lipoma; however, further study of the natural history is required.

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Makoto Ideguchi, Koji Kajiwara, Koichi Yoshikawa, Hisaharu Goto, Kazutaka Sugimoto, Takao Inoue, Sadahiro Nomura and Michiyasu Suzuki

OBJECTIVE

To avoid ischemic complications, it is important to consider the arteries in resection planning for lesions such as a vascular intraparenchymal tumor and arteriovenous malformation. Here, the clinical application of laser speckle flow imaging (LSFI) as a complementary method for the management of mass lesion–related arteries during surgery was evaluated.

METHODS

LSFI was performed in 12 patients with mass lesion–related arteries and brain tumor or arteriovenous malformation. The portable LSFI device was centered over the surgical field, and the relative cerebral blood flow (CBF) before and after the temporary interruption of the arteries was measured through continuous recording. CBF fluctuations permitted the classification of 3 kinds of artery—a feeding artery (FA), a “passing through” artery (PA), and a combined FA and PA (FA+PA)—based on decreased relative CBF in the inner resection area and unchanged CBF in the surrounding area (FA), unchanged CBF in the inner area and decreased CBF in the surrounding area (PA), or decreased CBF in both areas (FA+PA). This information allowed the appropriate management of these arteries and avoidance of postoperative ischemic complications.

RESULTS

Good visualization of CBF in the surgical field and relative CBF measurements in the regions of interest were achieved in real time with excellent spatiotemporal resolution. In 11 patients (92%) and 20 regions of interest, a decline in CBF was observed after temporary interruption of the FA (n = 8), PA (n = 2), and FA+PA (n = 2) types. There was a significant average reduction in CBF of 15.3% ± 29.0%. There were no ischemic complications, and only 1 patient had a postoperative ischemic lesion caused by resection through an artery that could not be viewed by LSFI due to a positional problem.

CONCLUSIONS

LSFI permits noninvasive and rapid intraoperative real-time recognition of mass lesion–related vasculature. This information can be used to avoid ischemic complications as a procedure complementary to neurophysiological monitoring.

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Fredrik Lundberg, Dai-Qing Li, Dan Falkenback, Tor Lea, Peter Siesjö, Sven Söderström, Bohdan J. Kudryk, Jonas O. Tegenfeldt, Sadahiro Nomura and Åsa Ljungh

Object. The pathogenesis of cerebrospinal fluid (CSF) shunt infection is characterized by staphylococcal adhesion to the polymeric surface of the shunt catheter. Proteins from the CSF—fibronectin, vitronectin, and fibrinogen—are adsorbed to the surface of the catheter immediately after insertion. These proteins can interfere with the biological systems of the host and mediate staphylococcal adhesion to the surface of the catheter. In the present study, the presence of fibronectin, vitronectin, and fibrinogen on CSF shunts and temporary ventricular drainage catheters is shown. The presence of fragments of fibrinogen is also examined.

Methods. The authors used the following methods: binding radiolabeled antibodies to the catheter surface, immunoblotting of catheter eluates, and scanning force microscopy of immunogold bound to the catheter surface. The immunoblot showed that vitronectin was adsorbed in its native form and that fibronectin was degraded into small fragments. Furthermore, the study demonstrated that the level of vitronectin in CSF increased in patients with an impaired CSF—blood barrier. To study complement activation, an antibody that recognizes the neoepitope of activated complement factor C9 was used. The presence of activated complement factor C9 was shown on both temporary catheters and shunts.

Conclusions. Activation of complement close to the surface of an inserted catheter could contribute to the pathogenesis of CSF shunt infection.

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Nobuhiro Tanaka, Masami Fujii, Hirochika Imoto, Joji Uchiyama, Kimihiko Nakano, Sadahiro Nomura, Hirosuke Fujisawa, Ichiro Kunitsugu, Takashi Saito and Michiyasu Suzuki

Object

The use of focal brain cooling to eliminate epileptic discharges (EDs) has attracted increasing attention in the scientific community. In this study, the inhibitory effect of selective hippocampal cooling on experimental hippocampal seizures was investigated using a newly devised cooling system with a thermoelectric (Peltier) chip.

Methods

A copper needle coated with silicone and attached to the Peltier chip was used for the cooling device. The experiments were performed first in a phantom model with thermography and second in adult male Sprague–Dawley rats in a state of halothane anesthesia. The cooling needle, a thermocouple, and a needle electrode for electroencephalography recording were inserted into the right hippocampus. Kainic acid (KA) was injected into the right hippocampus to provoke the EDs. The animals were divided into hippocampal cooling (10 rats) and noncooling (control, 10 rats) groups.

Results

In the phantom study, the cooling effects (9°C) occurred in the spherical areas around the needle tip. In the rats the temperature of the cooled hippocampus decreased below 20°C within a 1.6-mm radius and below 25°C within a 2.4-mm radius from the cooling center. The temperature at the needle tip decreased below 20°C within 1 minute and was maintained at the same level until the end of the cooling process. The amplitude of the EDs was suppressed to 68.1 ± 4.8% of the precooling value and remained low thereafter. No histological damage due to cooling was observed in the rat hippocampus.

Conclusions

Selective hippocampal cooling effectively suppresses the KA-induced hippocampal EDs. Direct hippocampal cooling with a permanently implantable system is potentially useful as a minimally invasive therapy for temporal lobe epilepsy and therefore could be an alternative to the temporal lobectomy.

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Hisashi Kubota, Ehichi Suehiro, Hiroshi Yoneda, Sadahiro Nomura, Koji Kajiwara, Masami Fujii, Hirosuke Fujisawa, Shoichi Kato and Michiyasu Suzuki