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T Asazuma

Publications and source records attributed to T Asazuma.

18 recordsLinked to original sources
PubMed2006

Severe scoliosis associated with Costello syndrome: a case report.

Costello syndrome is characterised by dwarfism, unique cutaneous lesions, a distinct facial gestalt, and mental retardation. There have been no detailed reports of severe spinal deformities requiring surgical treatment as a complication of Costello syndrome. We report a case of a 10-year-old girl with progressive scoliosis associated with Costello syndrome. She underwent anterior release and posterior surgical correction and fusion from T5 to L2 using a third generation hook and rod system plus spinous process wiring. Congenital portal vein deficiency and coagulopathy were other major complications. At 15-month follow-up, the patient had good balance and no evidence of instrumentation failure.

Abnormalities, Multiple↗
PubMed2004

Primary cervical spinal epidural Extra-osseous Ewing's sarcoma.

Cases of primary spinal epidural Extra-osseous Ewing's sarcoma (EES) are rarely seen and a good prognosis for EES cannot be expected since a high incidence of local recurrence and metastasis frequently occur. We present a case of cervical spinal epidural EES in a 7-year-old girl with long survival after tumour resection. She also received adjuvant treatment with peripheral blood stem cell transplantation (PBSCT). This management successfully improved her condition and she was in complete remission without neurological deficit 60 months after surgery. Such a good prognosis of EES in the cervical spine is very rare. It is likely that magnetic resonance imaging (MRI) lead to a diagnosis of this rare type of EES at an early stage of the disease. PBSCT could be useful as an adjuvant to prolong the period of complete remission.

Child↗
PubMed2003

Tissue engineering of the intervertebral disc with cultured annulus fibrosus cells using atelocollagen honeycomb-shaped scaffold with a membrane seal (ACHMS scaffold).

The objective of the study was to investigate the regeneration of intervertebral discs after laser discectomy using tissue engineering procedures. Annulus fibrosus (AF) cells from the intervertebral discs of Japanese white rabbits were cultured in an atelocollagen honeycomb-shaped scaffold with a membrane seal (ACHMS scaffold), to produce a high-density, three-dimensional culture for up to 3 weeks. Although the DNA content in the scaffold increased at a lower rate than that in the monolayer culture, expression of type II collagen and glycosaminoglycan accumulation in the scaffold were at higher levels than in the monolayer. The AF cells that had been cultured in the scaffold for 7 days were allografted into the lacunae of intervertebral discs of recipients (40 rabbits, 14-16 weeks old; average weight, 3.2 kg), whose nucleus pulposus (NP) had been vaporised with an ICG dye-enhanced laser. The allografted cultured AF cells survived and produced hyaline-like cartilage. Furthermore, the narrowing of the intervertebral disc space of the cell-containing scaffold insertion groups was significantly inhibited after 12 post-operative weeks.

Animals↗
PubMed2003

Vertebral arch reconstruction based on 90 degree rotational laminoplasty after removal of spinal cord and cauda equina tumours.

BACKGROUND: A variety of procedures for reconstructing the spine following the removal of spinal cord and cauda equina tumours have been developed to prevent postoperative spinal deformities and nerve entrapment. The purpose of this paper is to introduce a new reconstructive procedure based on rotational laminoplasty and to report preliminary results in a small series. METHOD: The trough is drilled at the border of the laminae and articular processes and the ligamentum flavum is resected on its cephalocaudal aspect, so the vertebral arch can be separated as a single mass. After tumour resection, the vertebral arch is removed en bloc with the laminae, and is rotated 90 degrees and placed on the articular facets and fixed using suture passing through holes drilled in the bone. FINDINGS: One man and six women underwent rotational laminoplasty following resection of spinal or cauda equina tumours. Operative exposure was good and permitted complete resection. Patients did well postoperatively from both spine-surgical and neurosurgical points of view. Computed tomography documented a bony union with preservation of widely patent spinal canal. INTERPRETATION: Rotational laminoplasty affords a satisfactory operative exposure for the resection of large, complex lesions. It creates a widely patent, stable spinal canal easily, without the need for special tools.

Aged↗
PubMed2003

Lumbar disc herniation associated with separation of the posterior ring apophysis: analysis of five surgical cases and review of the literature.

BACKGROUND: Separation of the posterior ring apophysis of an adjacent vertebral body can sometimes accompany lumbar intervertebral disc herniation. The condition can be both difficult to detect in conventional radiographs and is somewhat controversial to treat. Although there is general agreement on the frequent need for surgery, there is no consensus on the choice of operation. One procedure, posterior lumbar interbody fusion (PLIF), has never been examined for effectiveness. METHOD: Computed tomography (CT) either or with discography (CTD) was compared to plane radiographs and magnetic resonance imaging (MRI) for its ability to reveal the fragmentation. Five cases were identified and the severity of the condition evaluated using the Japanese Orthopaedic Association's Assessment of Treatment for Low Back Pain (JOA score). The fragments were removed by impaction with a shoe shaped device and posterior lumbar interbody fusion (PLIF) was performed using autogenous iliac crest bone. A second evaluation using the JOA score was performed after a 4 to 5 year follow-up. FINDINGS: CT identified the separation in all 5 cases while plain films showed the defect in two and MRI in none. JOA scores prior to surgery were between 5 and 19 (mean, 13) and between 25 and 29 (mean, 27.4) at follow-up. The scores represented a recovery of 80% to 100%t (mean, 89.4). INTERPRETATION: CT and CT discography (CTD) are the diagnostic tools of choice for detecting this condition. Posterior lumbar interbody fusion (PLIF) is an effective procedure for patients who have low back pain due to lumbar disc herniation accompanied by a separation of the posterior ring apophysis.

Adolescent↗
PubMed2003

Clinical features associated with recurrence of tumours of the spinal cord and cauda equina.

STUDY DESIGN: Retrospective review of consecutive cases of recurrent spinal cord and cauda equina tumours. OBJECTIVES: We sought to identify factors and conditions resulting in re-operation to treat recurrences of spinal cord and cauda equina tumours. SETTING: Keio University Hospital, Tokyo, Japan. METHODS: Re-operation was performed in 39 patients with spinal cord and cauda equina tumours. Times of operation, interval between operations, affected spinal level, tumour site on cross section, configurations among dumb-bell tumours, and pathologic diagnoses were analysed. Recurrence rates were defined in terms of the number of cases with re-operation due to tumour recurrence relative to the total number of surgical cases for the same period at our institution. RESULTS: Recurrence rates were relatively high for intradural, extramedullary tumours and for tumours located anteriorly rather than laterally. Of patients with intradural, extramedullary plus extradural tumours who underwent initial surgery at our hospital, 75% (9/12) recurred; all tumours had dumb-bell-type configurations. The overall rate of re-operation due to tumour recurrence in 249 cases was 7.2% at our institution. By tumour types, 40% of malignant schwannomas recurred (2/5), as did 35.7% of neurofibromas (5/14), and 33.3% of ependymomas (6/18). CONCLUSION: Risk factors for tumour recurrence were anterior location, an intradural, extramedullary plus extradural site, extensive dumb-bell tumours, and pathologic diagnoses of neurofibroma, ependymoma, or malignant schwannoma.

Adolescent↗
PubMed2001

Glycosaminoglycan accumulation in primary culture of rabbit intervertebral disc cells.

STUDY DESIGN: With the heterogeneity of the intervertebral disc as the focus, intervertebral discs from normal young rabbits were separated into nucleus pulposus (NP), inner anulus fibrosus (IAF), and outer anulus fibrosus (OAF) zones. Disc cells from each zone were isolated and propagated under monolayer and within agarose gel culture. The metabolism of these cultured disc cells was examined in terms of glycosaminoglycan (GAG) accumulation. OBJECTIVES: The object was to study the metabolism of disc cells derived from each zone and characterize them on the basis of GAG accumulation and composition. SUMMARY OF BACKGROUND DATA: It has been shown that three-dimensional culture systems, such as within-agarose gels or in alginate beads, permit long-term maintenance of the articular chondrocyte phenotype in vitro. However, little has been reported on how the metabolism of intervertebral disc cells, especially GAG accumulation, is affected by different culture conditions. METHODS: Cells from each zone were subjected to monolayer or three-dimensional culture for up to 12 days. GAG accumulation in the different culture systems was analyzed using chemical, histologic, and immunohistologic methods. Differences of GAG and DNA content among NP, IAF, and OAF cells were statistically evaluated by analysis of variance. The data of keratin sulfate content in three-dimensional culture were compared with that in monolayer culture using nonparametric Mann-Whitney U test. RESULTS: Monolayer culture revealed that increases in GAG content were significantly higher in IAF cells than in OAF cells. However, in three-dimensional culture GAG content was similar in the two groups. AF cells in three-dimensional cultures showed immunohistochemical localization of chondroitin sulfate and keratan sulfate, suggesting the existence of pericellular matrix. High performance liquid chromatography confirmed the expression of keratan sulfate in cultured cells. CONCLUSIONS: GAG accumulation in cultures of cells from different zones of the intervertebral disc varied according to the culture conditions used. The importance of choosing the appropriate culture systems to meet the objectives of a study should be emphasized.

Analysis of Variance↗
PubMed2001

Use of a new ICG-dye-enhanced diode laser for percutaneous laser disc decompression.

BACKGROUND AND OBJECTIVE: The lasers used today for Percutaneous Laser Disc Decompression (PLDD) can not selectively ablate the nucleus pulposus (NP). We hypothesized that if indocyanine green dye were injected into the NP, 805 nm diode laser irradiation would result in selective and safe removal of NP tissue without damaging nearby tissues. STUDY DESIGN/MATERIALS AND METHODS: Twelve beagle dogs were used for three experiments, i.e., determination of attenuation coefficients of NP and AF, determination of weight of NP before and after laser irradiation, and histopathological study. RESULTS: The attenuation coefficient at 805 nm of NP which had been homogenized in the presence of ICG was 2521.3/cm. Upon application of the diode laser at a power of 1, 3, or 5 W (the intensity of laser irradiation: 0.353, 1.061, or 1.768 x 10(3) W/cm(2)) to NPs into which ICG had been injected, the weight of the NPs decreased by a mean 20, 45, and 65%, respectively. Macroscopic and microscopic examination of the discs after PLDD showed that only the NP where the tissues were stained by ICG were removed. CONCLUSIONS: These results indicated that the combined use of ICG and diode laser irradiation effectively and selectively ablates the NP with low laser power.

Animals↗
PubMed2000

Nerve stimulating system for peripheral nerve tumor resection under the thoracoscope.

The authors report a newly devised nerve stimulator and its clinical application in thoracoscopic surgery. The stimulator is a monopolar system, that has a long extension between the electrodes and the handle. The stimulator is inserted into the chest cavity through a portal, and is used to distinguish motor nerves from the surrounding tissue and to determine whether there is nerve involvement with tumor. The tumor is then safely and rapidly resected by thoracoscopic technique and the major nerves are spared. This method was used in two clinical cases, with excellent results obtained, and with no major complications.

Adult↗
PubMed2000

Body height correction in scoliosis patients for pulmonary function test.

We studied standing anteroposterior roentgenograms from 140 scoliosis patients and obtained a correction equation for body height by Cobb angle. This equation is applicable to patients with a double curve or special curve pattern as well as patients with a single curve. The repeatability of the method examined with this equation was higher than that with the previous correction method for body height by Cobb angle, and the difference between the corrected values and the measured values was small. Therefore, this method is considered to be more reliable.

Journal Article↗
PubMed1999

Ependymomas of the spinal cord and cauda equina: An analysis of 26 cases and a review of the literature.

STUDY DESIGN: Retrospective review. OBJECTIVES: To clarify the clinical features of patients with spinal ependymomas and to compare the clinical results between the patients in whom microsurgical technique and spinal cord monitoring were used intraoperatively and the patients in whom they were not used. SETTING: Keio University Hospital, Tokyo, Japan. METHODS: Twenty-six consecutive patients with spinal ependymomas were treated surgically between 1958 and 1995. All patients underwent tumor resection through a posterior approach. Complete tumor resection was possible in 15 patients (57. 7%), and subtotal tumor resection (more than 90%) was done in two patients (7.7%). Only a partial tumor resection (less than 90%) was performed in the remainder of the patients (34.6%). The operative results of the patients were evaluated by the Japanese Orthopaedic Association Scoring System (JOA score) and its recovery rate. RESULTS: The overall average recovery rate was 18.3%. The mean recovery rate was 14.4% in cervical lesion, 11.1% in thoracic lesion and 40% in lumbar lesion. The recovery rate of eight patients with cervical ependymomas who underwent tumor resection under both microscopic surgical procedure and intraoperative spinal cord monitoring was 37.1% although the recovery rate of the rest of the patients was -1.6%. There was a statistical difference between the two groups (P<0.02). The survival rate of patients following complete excision was statistically better compared to that of patients after incomplete resection. CONCLUSION: Both microsurgical technique and spinal cord monitoring are indispensable to achieve total removal of ependymomas and to obtain improvement of neurological recovery.

Adolescent↗
PubMed1997

Vascularized fibula graft for spinal fusion in severe cervical kyphosis due to neurofibromatosis.

A successful anterior spinal fusion using vascularized fibula graft in the case of a 17-year-old male with severe cervical kyphosis due to neurofibromatosis is reported. Anterior spinal fusion at C2-7 using the fibula graft was performed with spinous process wiring. The kyphosis was corrected from 85 to 38 degrees. Bony fusion was obtained in 5 months without loss of correction.

Adolescent↗
PubMed1997

Spinal fusion using a vascularized fibular bone graft for a patient with cervical kyphosis due to neurofibromatosis.

We performed an anterior spinal fusion using a vascularized fibular bone graft combined with posterior fusion for a patient with severe cervical kyphosis due to neurofibromatosis. The kyphosis was corrected from 85 degrees preoperatively to 38 degrees postoperatively. A vascularized fibular bone graft is a useful surgical procedure in selected patients to obtain successful bony union.

Adolescent↗
PubMed1996

Management of patients with an incomplete cervical spinal cord injury.

Forty-five patients with incomplete cervical spinal cord injuries were examined as to the mechanism of injury, neurological deficits in the initial stage and differences in treatment. Nineteen (42.2%) were treated non-surgically and 26 (57.8%) surgically. Their injuries could be divided into seven types of cervical spinal cord injury according to Usui's classification. Neurological changes were evaluated with Frankel's grading system. The neurological prognosis was relatively better in those with a unilateral cord injury type, but there was no statistical difference. Thirty-seven patients (82.2%) showed neurological improvement of at least one Frankel grade. There was no statistical difference between the surgical and non-surgical groups regarding neurological improvement, but all who underwent early surgery (within 4 weeks of being injured) improved. Surgical treatment was considered to be indicated for patients with cervical spinal canal narrowing, when satisfactory neurological improvement is not obtained by conservative treatment.

Accidental Falls↗
PubMed1994

Realignment of postoperative cervical kyphosis in children by vertebral remodeling.

STUDY DESIGN: This study analyzed radiographically change in the sagittal curvature of the cervical spine after atlantoaxial (C1-C2) posterior fusion in children. OBJECTIVES: This study clarified the process of spinal remodeling after postoperative cervical deformation in children. SUMMARY OF BACKGROUND DATA: Postoperative spinal deformations in children are observed frequently. However, there have been only a few reports on postoperative changes in the sagittal curvature of the cervical spine and spinal remodeling after those changes. METHODS: Between 1979 and 1991, there was a total of 12 children who underwent C1-C2 posterior fusions. The average age at the time of surgery was 9.8 years. The alignment of the cervical spine was classified into four groups (lordosis, straight, kyphosis, and swan-neck deformity). Radiographic findings suggestive of the remodeling were as follows: 1) new bone formation on the anterior vertebral cortex, and 2) increase in body/canal ratio (BCR). The follow-up period averaged 6.2 years. RESULTS: Postoperative cervical malalignment (kyphosis or swan-neck deformity) occurred in four patients. In all four patients, new bone formation and increase in BCR at the apex of kyphosis were observed. Therefore, there was gradual improvement of the malalignment by vertebral remodeling. This phenomenon was not observed in eight patients with normal alignment. CONCLUSION: Realignment of postoperative cervical kyphosis by vertebral remodeling was observed in children. The results of this study suggested that remodeling occurred even in the spine, which was similar to the remodeling in long bones.

Atlanto-Axial Joint↗
PubMed1990

Intersegmental spinal flexibility with lumbosacral instrumentation. An in vitro biomechanical investigation.

Flexibility of the porcine lumbosacral spine was measured after application of six different types of surgical instrumentation, and in a control state. Fifteen adult pig spines were tested with flexion, extension, lateral bending, and axial rotation torques applied to the upper end with the pelvis fixed. Instrumentation was applied across two lumbar segments and the lumbosacral level (L5-6, L6-7, and L7-S1). Stereophotogrammetry was used to track markers applied to each vertebra. Intersegmental motion was measured as three angles and as the relative linear translation of adjacent transverse processes and spinous processes. Results showed that all instrumentation systems reduced intersegmental motion compared with the control state, except for minimal reduction at L5-6 by Harrington instrumentation in all loading directions, especially axial rotation. The pedicle screw systems were always the most rigid. After applying instrumentation, there were differences in the motion occurring at different anatomic levels, most commonly with the least motion occurring in the middle of the instrumented segment (L6-7). When intervertebral motion was expressed as the linear motion between adjacent spinous and transverse processes, the usual site of posterolateral fusion, it was 0.6 to 1.8 mm per degree of angular motion at the transverse processes and 1.3 to 2.1 mm per degree at spinous processes.

Animals↗
PubMed1987

[Studies on dynamic posture in normal persons and scoliotic patients].

Dynamic posture of 127 normal males, 144 normal females and 68 scoliotic patients was studied by a system utilizing Moiré topography, a video recorder and Apple II microcomputer system. The normal group was divided into five subgroups by age and the scoliotic group into three subgroups according to the Cobb angle. The following results were obtained: The clockwise rotation during on-the-spot marching was larger in early juvenile females. The rotation movement during on-the-spot marching was almost symmetrical in normal individuals older than seven years of age. In scoliotic patients, the trunk movement during on-the-spot marching was asymmetric. The angle of rotation during on-the-spot marching was significantly larger in scoliotic patients than in normal adolescent females. A propensity was found that the greater the scoliosis curve was the less was the rotation angle of the trunk during on-the-spot marching.

Adolescent↗