Accuracy of Multilevel Registration in Image-Guided Pedicle Screw Insertion for Adolescent Idiopathic Scoliosis

This is a non-final version of an article published in final form in SPINE 35(3): 347-352, 2010.Study Design. Retrospective clinical study. Objective. To assess the accuracy of multilevel registration for skip pedicle screw placement during image-guided, computer-assisted spine surgery, in the setting of adolescent idiopathic scoliosis (AIS). Summary of Background Data. Computerized frameless stereotactic image-guidance has been used recently to improve pedicle screw placement accurately and safety during spine surgery. Because of possible intervertebral motion and usual difference in patients' position between preoperative imaging and surgery, the imaging model and the surgically exposed spine may be significantly discordant. Consequently, current protocols suggested separate registration of each spinal level (single-level registration) before respective pedicle screw placement, a time-consuming process. Moreover, although multilevel registration for lumbar spine has been reported, and that for thoracic spine has not. Methods. A total of 19 patients ( 1 male and 18 females; mean age, 13.9 years) with AIS who underwent multilevel registration for skip pedicle screw placement were included. Variables including surgical time, blood loss, preoperative and 2-year postoperative Cobb angle, correction rate, and postoperative screw position by computed tomography image were evaluated. Mean registration error after point merge and again after surface merge were recorded for each consecutive vertebra of each case. Results. Mean surgical time was 310 minutes ( range, 168-420 min). Mean blood loss 1138 g (range, 300-2300 g). Cobb angle before operation and at 2 years postoperation was 62.4 degrees (43 degrees-100 degrees) and 21.6 degrees (9 degrees-42 degrees), respectively. Mean correction rate 66.2% (39.7%-84.5%). Total 265 screws were inserted with computed tomography-based navigation system. Pedicle violation was observed in only 4 screws (1.5%). No neurovascular complication occurred. After point merge, average Mean registration error of all cases was 1.69 +/- 0.52 mm, and after surface merge was 0.51 +/- 0.16 mm. Conclusion. Multilevel registration may decrease operative time without compromising accuracy of pedicle screw placement afforded by this technique in the setting of AIS.http://journals.lww.com/spinejournal/pages/default.aspx | http://journals.lww.com/spinejournal/pages/default.aspxArticleSPINE. 35(3):347-352 (2010)journal articl

Hodgkin's disease of the thoracic vertebrae

BACKGROUND CONTEXT: Hodgkin's disease rarely occurs in the spine, which is usually a setting for the advanced form of the disease. PURPOSE: To describe an unusual case of isolated, primary spinal Hodgkin's disease and to draw attention to this disease as a possible diagnosis in patients with mixed inflammatory cell infiltrate lesions located in the thoracic spine. STUDY DESIGN/SETTING: A case report of a 28-year-old woman who presented with back pain and progressive weakness in the lower extremities as a result of spinal cord compression from Hodgkin's disease of the thoracic vertebrae. METHODS: We report a new case of spinal cord compression resulting from Hodgkin's disease of the thoracic vertebrae. Decompression surgery was performed in the patient, followed by antibiotic treatment. RESULTS: Antibiotic therapy temporarily improved inflammation and fever. However, magnetic resonance imaging (MRI) evaluation showed that the inflammatory reaction in the lesion was not completely resolved. The disease progressed and later investigations revealed Hodgkin's disease, which improved with a course of chemotherapy and radiation. CONCLUSIONS: Hodgkin's disease should be considered in the differential diagnosis of spinal neoplastic lesions with clinical features similar to spondylitis. Because MRI evaluation showed that the vertebral disc was maintained in this case, the presence of a tumor rather than inflammation should have been suspected.ArticleSPINE JOURNAL. 13(8):E59-E63 (2013)journal articl

Computer-assisted hemivertebral resection for congenital spinal deformity

No studies have reported on osteotomies utilizing a navigation system in congenital scoliosis surgery. This study aimed to evaluate the surgical outcomes of eight patients with congenital scoliosis or kyphoscoliosis due to hemivertebrae treated by computer-assisted hemivertebral resection using only a posterior approach. Eight consecutive patients (two scoliotics and six kyphoscoliotics) managed by computer-assisted hemivertebral resection using only a posterior approach with transpedicular instrumentation were investigated retrospectively. A CT-based navigation system was used to confirm the positions of the vertebra, spinal cord and aorta in real-time when we inserted a pedicle screw and conducted the osteotomy. The mean patient age at surgery was 18 years (range 11-41 years). The mean follow-up was 46 months (range 18-84 months). Before surgery, the mean kyphotic curve was 55.8A degrees (range 26-83A degrees), and the mean scoliotic curve was 50.0A degrees (range 36-62A degrees). At the final follow-up period, the curves averaged 23.2A degrees (range 15-40A degrees) and 31.6A degrees (range 21-44A degrees), respectively, yielding kyphotic angle corrections of 32.7A degrees (range 11-58A degrees) and Cobb angle correction rates of 36.8% (range 24.1-48.3%). A total of 72 pedicle screws were inserted with the navigation system, and two screws revealed a perforating pedicle. No neurovascular complications occurred. The perforation rate was 2.8%. Hemivertebral resection via a single posterior approach is less invasive than combined anterior and posterior approaches; however, this procedure increases the risk of spinal cord and vascular injuries. Computer-assisted hemivertebral resection enables safe and accurate performance of a hemivertebral resection via a single posterior approach.ArticleJOURNAL OF ORTHOPAEDIC SCIENCE. 16(5):503-509 (2011)journal articl

Evaluation of clinical results and quality of life after surgical reconstruction for rheumatoid cervical spine

BACKGROUND CONTEXT: The EuroQol (EQ-5D) is a widely used comprehensive measure of health-related quality of life. There has been no study that has evaluated the health-related quality of life before and after the surgical reconstruction of rheumatoid arthritis (RA) cervical spine lesions using EQ-5D. PURPOSE: The present study aimed to evaluate the improvement of quality of life before and after surgical reconstruction of rheumatoid cervical spine using EQ-5D, and the surgical outcomes of cervical spine affected by RA. STUDY DESIGN: A retrospective study of the patients who underwent surgical reconstruction of cervical disorders in RA. PATIENT SAMPLE: Twenty-five patients (seven men, 18 women, mean age 62.2 years) who underwent surgical reconstruction of cervical disorders in RA were enrolled. OUTCOME MEASURES: Japanese Orthopaedic Association (JOA) score and EQ-5D. METHODS: Clinical symptoms were evaluated before surgery and at 2 years after surgery by measuring the JOA score. We also investigated health-related quality of life before surgery and outcome at 2 years after surgery using the EQ-5D questionnaire. RESULTS: Mean observation period was 46.3 months. Mean JOA score significantly improved from 9.1 +/- 4.5 points before surgery to 12.4 +/- 2.8 at the 2 years after surgery (p=.0001). All the EQ-5D data were improved at the 2 years after surgery, compared with the data before surgery; especially, pain (p=.005), usual activity (p=.005), mobility (p=.008), and anxiety/depression (p=.02) were significantly improved. Utility weight was 0.37 +/- 0.27 before surgery and 0.56 +/- 0.26 at the 2 years after surgery, showing significant improvement at the 2 years after surgery compared to before surgery (p=.002). CONCLUSIONS: The surgical reconstruction of rheumatoid cervical spine has been demonstrated to improve patients' health-related quality of life.ArticleSPINE JOURNAL. 13(4):391-396 (2013)journal articl

Mid-term results of computer-assisted cervical reconstruction for rheumatoid cervical spines

Study design A retrospective single-center study. Summary and background We routinely have used C1-C2 transarticular and cervical pedicle screw fixations to reconstruct highly destructed unstable rheumatoid arthritis (RA) cervical lesions. However, there is little data on midterm results of surgical reconstruction for rheumatoid cervical disorders, particularly, cervical pedicle screw fixation. Objectives The purpose of this study was to evaluate the mid-term surgical results of computer-assisted cervical reconstruction for such lesions. Methods Seventeen subjects (4 men, 13 women; mean age, 61 +/- 9 years) with RA cervical lesions who underwent C1-C2 transarticular screw fixation or occipitocervical fixation, with at least 5 years follow-up were studied. A frameless, stereotactic, optoelectronic, CT-based image-guidance system, was used for correct screw placement. Variables including the Japanese Orthopaedic Association (JOA) score, Ranawat class, EuroQol (EQ-5D), atlantodental interval, and Ranawat values before, and at 2 and 5 years after surgery, were evaluated. Furthermore, screw perforation rates were evaluated. Results The lesions included atlantoaxial subluxation (AAS, n = 6), AAS + vertical subluxation (VS, n = 7), and AAS + VS + subaxial subluxation (n = 4). There was significant neurological improvement at 2 years after surgery, as evidenced by the JOA scores, Ranawat class, and the EQ-5D utility weight. However, at 5 years after surgery, there was a deterioration of this improvement. The Ranawat values before, and at 2 and 5 years after surgery, were not significantly different. Major screw perforation rate was 2.1 %. No neural and vascular complications associated with screw insertion were observed. Conclusions Subjects with rheumatoid cervical lesions who underwent C1-C2 transarticular screw fixation or occipitocervical fixation using a pedicle screw had significantly improved clinical parameters at 2 years after surgery. However, there was a deterioration of this improvement at 5 years post surgery.ArticleJOURNAL OF ORTHOPAEDIC SCIENCE. 18(6):916-925 (2013)journal articl

The Japan Monkey Centre Primates Brain Imaging Repository of high-resolution postmortem magnetic resonance imaging: the second phase of the archive of digital records

超高磁場MRIで見る霊長類「全脳」神経回路の多様性 --分野横断型の霊長類脳標本画像リポジトリ：ヒト脳と精神・神経疾患の理解を加速する国際研究基盤--. 京都大学プレスリリース. 2023-05-22.A comparison of neuroanatomical features of the brain between humans and our evolutionary relatives, nonhuman primates, is key to understanding the human brain system and the neural basis of mental and neurological disorders. Although most comparative MRI studies of human and nonhuman primate brains have been based on brains of primates that had been used as subjects in experiments, it is essential to investigate various species of nonhuman primates in order to elucidate and interpret the diversity of neuroanatomy features among humans and nonhuman primates. To develop a research platform for this purpose, it is necessary to harmonize the scientific contributions of studies with the standards of animal ethics, animal welfare, and the conservation of brain information for long-term continuation of the field. In previous research, we first developed a gated data-repository of anatomical images obtained using 9.4-T ex vivo MRI of postmortem brain samples from 12 nonhuman primate species, and which are stored at the Japan Monkey Centre. In the present study, as a second phase, we released a collection of T2-weighted images and diffusion tensor images obtained in nine species: white-throated capuchin, Bolivian squirrel monkey, stump-tailed macaque, Tibet monkey, Sykes’ monkey, Assamese macaque, pig-tailed macaque, crested macaque, and chimpanzee. Our image repository should facilitate scientific discoveries in the field of comparative neuroscience. This repository can also promote animal ethics and animal welfare in experiments with nonhuman primate models by optimizing methods for in vivo and ex vivo MRI scanning of brains and supporting veterinary neuroradiological education. In addition, the repository is expected to contribute to conservation, preserving information about the brains of various primates, including endangered species, in a permanent digital form

Challenges of Transarticular Screw Fixation in Young Children: Report of Surgical Treatment of a 5-Year-Old Patient's Unstable Os-Odontoideum

Surgical procedures for atlantoaxial (C1–C2) fusion in young children are relatively uncommon. The purpose of this study was to report on a surgical treatment for a case of atlantoaxial instability caused by os-odontoideum in association with quadriparesis and respiratory paralysis in a 5-year-old girl. We present the patient's history, physical examination, and radiographic findings, describe the surgical treatment and a five year follow-up, and provide a literature review. The instability was treated by halo immobilization, followed by C1–C2 transarticular screw fixation using a computed tomography-based navigation system. At the five year follow-up, the patient had made a complete recovery with solid union. The authors conclude that C1–2 transarticular screw fixation is technically possible as in a case of atlantoaxial instability in a five-year-old child