Toshitaka Seki

Migration and differentiation of nuclear fluorescence-labeled bone marrow stromal cells after transplantation into cerebral infarct and spinal cord injury in mice

There is increasing evidence that bone marrow stromal cells (BMSC) have the potential to migrate into the injured neural tissue and to differentiate into the CNS cells, indicating the possibility of autograft transplantation therapy. The present study was aimed to clarify whether the mouse BMSC can migrate into the lesion and differentiate into the CNS cells when transplanted into the mice subjected to focal cerebral infarct or spinal cord injury. The BMSC were harvested from mice and characterized by flow cytometry. Then, the BMSC were labeled by bis‐benzimide, a nuclear fluorescence dye, over 24 h, and were stereotactically transplanted into the brain or spinal cord of the mice. The cultured BMSC expressed low levels of CD45 and high levels of CD90 and Sca‐1 on flow cytometry. A large number of grafted cells survived in the normal brain 4 weeks after transplantation, many of which were located close to the transplanted sites. They expressed the neuronal marker including NeuN, MAP2, and doublecortin on fluorescent immunohistochemistry. However, when the BMSC were transplanted into the ipsilateral striatum of the mice subjected to middle cerebral artery occlusion, many of the grafted cells migrated into the corpus callosum and injured cortex, and also expressed the neuronal markers 4 weeks after transplantation. In particular, NeuN was very useful to validate the differentiation of the grafted cells, because the marker was expressed in the nuclei and was overlapped with bis‐benzimide. Similar results were obtained in the mice subjected to spinal cord injury. However, many of the transplanted BMSC expressed GFAP, an astrocytic protein, in injured spinal cord. The present results indicate that the mouse BMSC can migrate into the CNS lesion and differentiate into the neurons or astrocytes, and that bis‐benzimide is a simple and useful marker to label the donor cells and to evaluate their migration and differentiation in the host neural tissues over a long period.

An interspinous process distractor (X STOP) for lumbar spinal stenosis in elderly patients: preliminary experiences in 10 consecutive cases.

Background Lumbar spinal stenosis (LSS) is often a position-dependent condition that is aggravated in extension and relieved in flexion. Methods Ten consecutive elderly patients with LSS were assessed postoperatively by magnetic resonance imaging and the Swiss Spinal Stenosis Questionnaire. Cross-sectional areas of the dural sac and intervertebral foramina at the stenotic level were measured postoperatively and compared with the preoperative values. Results Postoperatively the cross-sectional area of the dural sac increased 16.6 mm2 or 22.3% and intervertebral foramina increased 22 mm2 or 36.5%. The intervertebral angle and the posterior disc height changed significantly. Seventy percent of the patients were satisfied with the surgical outcome. Conclusion This new surgical method is effective in elderly LSS patients.

Graded Contusion Model of the Mouse Spinal Cord Using a Pneumatic Impact Device

OBJECTIVE This study examined the effects of varying magnitudes of controlled spinal cord impact to the mouse spinal cord on neurological and histopathological variables to obtain a mouse model of spinal cord injury (SCI). METHODS A laminectomy of the T10 vertebra was performed on anesthetized C57BL/6 mice. A pneumatic pressure-driven impact was performed on the spinal cord through the dura mater. Experimental groups were subdivided according to the energy of impact (0.25-mm-deep deformations): Group 1 (n = 5), impact velocity at 1 m/s; Group 2 (n = 5), impact velocity at 2 m/s; and Group 3 (n = 5), impact velocity at 3 m/s. Functional deficits over time were evaluated up to 28 days after SCI by testing hindlimb reflex and coordinated motor function. The extent of the lesions was analyzed histopathologically and quantified by a morphometric measurement. RESULTS Mice of all groups exhibited profound functional deficits immediately after injury and subsequent gradual symptomatic recovery. The degrees of recovery were precisely correlated with the magnitudes of impact. The extent of resultant cord lesions was highly reproducible among animals, with little variance: means ± standard deviation, 0.86 ± 0.06/100 mm3 in Group 1; 2.4 ± 0.28/100 mm3 in Group 2; and 11.0 ± 1.0/100 mm3 in Group 3. CONCLUSION Our results indicate that this model provides constant functional and histopathological lesions according to impact energy. This new mouse model of SCI opens a new avenue for studies investigating roles and/or effects of specific genes in the recovery process of SCI.

Anterior Decompression of the Atlantoaxial Vertebral Artery to Treat Bow Hunter's Stroke: Technical Case Report

OBJECTIVE AND IMPORTANCE Bow hunters stroke is a symptomatic vertebrobasilar insufficiency caused by stenosis or occlusion of the vertebral artery at the C1C2 level with head rotation. No case of anterior decompression of the vertebral artery for surgical treatment of bow hunters stroke has been reported. CLINICAL PRESENTATION A 47-year-old male patient presented with repeated episodes of unconsciousness caused by turning his head approximately 40 degrees to the right; he recovered consciousness within approximately 10 seconds after his head was returned to the neutral position. Angiography revealed an occluded right vertebral artery and temporary occlusion of the left vertebral artery, at the level of the C2 transverse foramen, when the patients head was turned approximately 40 degrees to the right. INTERVENTION Anterior decompression of the left vertebral artery at the transverse foramen of the axis was performed. Postoperative angiography demonstrated sufficient flow in the left vertebral artery even when the neck was rotated. CONCLUSION The patient was discharged without neurological deficits. We demonstrate that simple surgical untethering of the vertebral artery at the transverse foramen of the axis is an effective method of treatment that avoids the limitation of head rotation. The advantage of this procedure is that it does not result in postoperative restriction of the patients neck movements. The anterior approach, with decompression of the transverse foramen of the axis, in the present case provided adequate exposure of the vertebral artery and resulted in a satisfactory outcome.

Mechanistic insights into posttraumatic syringomyelia based on a novel in vivo animal model. Laboratory investigation.

OBJECT Although posttraumatic syringomyelia (PTS) develops in up to 30% of patients after spinal cord injury (SCI), the pathophysiology of this debilitating complication is incompletely understood. To provide greater insight into the mechanisms of this degenerative sequela of SCI, the authors developed and characterized a novel model of PTS. METHODS The spinal cords of 64 female Wistar rats were injured by 35-g modified aneurysm clip compression at the level of T6-7. Kaolin (5 microl of 500 mg/ml solution) was then injected into the subarachnoid space rostral to the site of the injury to induce inflammatory arachnoiditis in 22 rats. Control groups received SCI alone (in 21 rats), kaolin injection alone (in 15 rats), or laminectomy and durotomy alone without injury (sham surgery in 6 rats). RESULTS The combination of SCI and subarachnoid kaolin injection resulted in a significantly greater syrinx formation and perilesional myelomalacia than SCI alone; SCI and kaolin injection significantly attenuated locomotor recovery and exacerbated neuropathic pain (mechanical allodynia) compared with SCI alone. We observed that combined SCI and kaolin injection significantly increased the number of terminal deoxytransferase-mediated deoxyuridine triphosphate nick-end labeled-positive cells at 7 days after injury (p<0.05 compared with SCI alone) and resulted in a significantly greater extent of astrogliosis and macrophage/microglial-associated inflammation at the lesion (p<0.05). CONCLUSIONS The combination of compressive/contusive SCI with induced arachnoiditis results in severe PTS and perilesional myelomalacia, which is associated with enhanced inflammation, astrogliosis, and apoptotic cell death. The development of delayed neurobehavioral deficits and neuropathic pain in this model accurately reflects the key pathological and clinical conditions of PTS in humans.

Calculation of rotational setup error using the real-time tracking radiation therapy (RTRT) system and its application to the treatment of spinal schwannoma.

PURPOSE The efficacy of a prototypic fluoroscopic real-time tracking radiation therapy (RTRT) system using three gold markers (2 mm in diameter) for estimating translational error, rotational setup error, and the dose to normal structures was tested in 5 patients with spinal schwannoma and a phantom. METHODS AND MATERIALS Translational error was calculated by comparing the actual position of the marker closest to the tumor to its planned position, and the rotational setup error was calculated using the three markers around the target. Theoretically, the actual coordinates can be adjusted to the planning coordinates by sequential rotation of gamma degrees around the z axis, beta degrees around the y axis, and alpha degrees around the x axis, in this order. We measured the accuracy of the rotational calculation using a phantom. Five patients with spinal schwannoma located at a minimum of 1-5 mm from the spinal cord were treated with RTRT. Three markers were inserted percutaneously into the paravertebral deep muscle in 3 patients and surgically into two consecutive vertebral bones in two other patients. RESULTS In the phantom study, the discrepancies between the actual and calculated rotational error were -0.1 +/- 0.5 degrees. The random error of rotation was 5.9, 4.6, and 3.1 degrees for alpha, beta, and gamma, respectively. The systematic error was 7.1, 6.6, and 3.0 degrees for alpha, beta, and gamma, respectively. The mean rotational setup error (0.2 +/- 2.2, -1.3 +/- 2.9, and -1.3 +/- 1.7 degrees for alpha, beta, and gamma, respectively) in 2 patients for whom surgical marker implantation was used was significantly smaller than that in 3 patients for whom percutaneous insertion was used (6.0 +/- 8.2, 2.7 +/- 5.9, and -2.1 +/- 4.6 degrees for alpha, beta, and gamma). Random translational setup error was significantly reduced by the RTRT setup (p < 0.0001). Systematic setup error was significantly reduced by the RTRT setup only in patients who received surgical implantation of the marker (p < 0.0001). The maximum dose to the spinal cord was estimated to be 40.6-50.3 Gy after consideration of the rotational setup error, vs. a planned maximum dose of 22.4-51.6 Gy. CONCLUSION The RTRT system employing three internal fiducial markers is useful to reduce translational setup error and to estimate the dose to the normal structures in consideration of the rotational setup error. Surgical implantation of the marker to the vertebral bone was shown to be sufficiently rigid for the calculation of the rotational setup error. Fractionated radiotherapy for spinal schwannoma using the RTRT system may well be an alternative or supplement to surgical treatment.

Hiccups Attributable to Syringobulbia and/or Syringomyelia Associated with a Chiari I Malformation: Case Report

OBJECTIVE AND IMPORTANCEApproximately 20 to 50% of patients with syringomyelia associated with Chiari malformations exhibit cranial nerve or cerebellar symptoms. However, hiccups represent a rare clinical manifestation of this disorder. We report a case of intractable hiccups resulting from syringobulbia associated with a Chiari I malformation, which was successfully treated with foramen magnum decompression. CLINICAL PRESENTATIONWe report the case of a patient who presented with syringomyelia and syringobulbia associated with a Chiari I malformation, manifested as intractable hiccups and neurological deficits. Magnetic resonance imaging scans demonstrated syringobulbia in the dorsal medullary region and a large cervical syrinx from C2 to C6–C7, associated with a Chiari I malformation. INTERVENTIONForamen magnum decompression and a C1 laminectomy were performed. One month later, the intractable hiccups disappeared and the neurological symptoms demonstrated improvement. CONCLUSIONPostoperative magnetic resonance imaging scans demonstrated enlargement of the subarachnoid space in the posterior fossa and disappearance of the syringobulbia. There has been no recurrence of intractable hiccups and syringobulbia in 6 months after surgery. Magnetic resonance imaging of the brainstem is an important diagnostic procedure for intractable hiccups, because syringobulbia associated with a Chiari malformation represents a surgically treatable disorder, although the incidence is low.

Role of the bcl-2 gene after contusive spinal cord injury in mice.

OBJECTIVEApoptosis is indicated to have an important role in the secondary injury mechanisms of acute spinal cord injury (SCI). The proto-oncogene bcl-2 has been demonstrated to prevent apoptotic cell death in a wide variety of cell types. This study examined the recovery of behavioral function and histopathological variables after controlled-impact SCI in human bcl-2 transgenic (TG) mice and control mice. METHODSSix bcl-2 TG mice and five control mice were subjected to controlled-impact SCI of moderate severity at T10, with the use of a pneumatic impact device (0.25-mm-deep deformation; impact velocity, 2 m/s). Functional deficits were evaluated at times up to 28 days after SCI, with assessments of hindlimb reflexes and coordinated motor function. The extents of the lesions were histopathologically analyzed and quantified with morphometric measurements. RESULTSBoth control and bcl-2 TG mice exhibited profound deficits immediately after injury, with subsequent gradual symptomatic recovery. The mean functional scores for the control mice were lower than those for the bcl-2 TG mice, although the Mann-Whitney U test revealed no significant differences. The mean lesion volume for the bcl-2 TG mice (mean ± standard deviation, 2.9 ± 1.1 × 10−2 mm3) was significantly lower than that for the control mice (5.1 ± 0.8 × 10−2 mm3; unpaired t test, P = 0.0101). Immunohistological analysis of the spinal cords from the bcl-2 TG mice revealed marked expression of Bcl-2 at the injury site and in adjacent regions. CONCLUSIONOur results suggest that overexpression of the bcl-2 gene may play a protective role in neuropathological sequelae after SCI.

Pierre-Robin syndrome associated with Chiari type I malformation

Case reportPierre-Robin syndrome (PRS) is a rare congenital malformation that shows severe micrognathia and cleft soft palate. A 15-year-old boy who was admitted with occipital headache and gait disturbance was diagnosed with PRS. Radiological evaluation revealed severe herniation of the cerebellar tonsil and multiple craniovertebral osseous anomalies. We carried out foramen magnum decompression (FMD) with duroplasty. Postoperative MRI showed the cerebellar tonsil was freed from strangulation.Result and conclusionThis patient presented with the common finding between PRS and Chiari type I on the embryological aspect by illustrating pathophysiology of the Chiari I malformation. To our knowledge, this is the first reported case of PRS associated with Chiari malformation type I.

A new ceramic interspinous process spacer for lumbar spinal canal stenosis.

OBJECTIVE Because surgery in elderly patients should be minimally invasive, interspinous process distraction has been widely used in this group to treat lumbar canal stenosis. We developed a new interspinous process distraction spacer composed of hydroxyapatite ceramic. In this work, we demonstrate the usefulness of this novel device. METHODS Since 2003, we operated on 19 elderly patients with lumbar canal stenosis, including 14 men and five women. Their mean age was 70.1 years. We compared the intervertebral angle, posterior disc height, and interspinous process distance on midsagittal magnetic resonance images obtained before and after the surgery. We also assessed clinical outcomes by using the Visual Analog Scale and the Zurich Claudication Questionnaire. RESULTS The average operation time per level was 44.7 minutes. Postoperatively, there were significant changes in the angle (from 12.5 to 8.6 degrees, P < 0.0001), the posterior disc height (from 10.6 to 13.1 mm, P < 0.0001), and the interspinous process distance (from 9.7 to 14.1 mm, P < 0.0001). The clinical outcomes, which we assessed by using the Visual Analog Scale and the Zurich Claudication Questionnaire, were considered satisfactory. (Visual Analog Scale, from 6.88 to 3.00; Zurich Claudication Questionnaire, symptom severity domain from 2.94 to 1.92, physical function from 2.51 to 1.73.) CONCLUSION Our ceramic spacer is useful in the treatment of elderly patients with lumbar canal stenosis. Treatment comprises an easy surgical procedure and produces no metal artifact on radiological evaluations, such as magnetic resonance imaging and computed tomographic scans.