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H Boehm

Publications and source records attributed to H Boehm.

10 recordsLinked to original sources
PubMed2006

The 3D-based scaling index algorithm: a new structure measure to analyze trabecular bone architecture in high-resolution MR images in vivo.

INTRODUCTION: The purpose of this study was to obtain different structure measures as the three-dimensional (3D)-based scaling index method (SIM) and standard two-dimensional (2D) bone histomorphometric parameters from high-resolution (HR) magnetic resonance (MR) images of the distal radius and to compare these parameters with bone mineral density (BMD) in their diagnostic performance to differentiate postmenopausal patients with and without vertebral fractures. METHODS: Axial HR-MR images of the distal radius were obtained at 1.5 T in 40 postmenopausal women (17 with osteoporotic spine fractures and 23 controls). Trabecular microarchitecture analysis was performed using the new structure measure mP(alpha), derived from the SIM, as well as standard morphological 2D parameters. BMD of the spine was obtained using quantitative computed tomography (QCT). Receiver operating characteristic (ROC) analyses were used to determine diagnostic performance in differentiating both groups. Results were validated by bootstrapping techniques. RESULTS: Significant differences between both patient groups were obtained using mP(alpha), 2D parameters, and spine BMD (p<0.05). In comparison with the 2D texture parameters [area under the curve (AUC) up to 0.67], diagnostic performance was significantly higher for mP(alpha)(AUC=0.85; p<0.05). There was a trend for a higher AUC value for mP(alpha) compared with BMD of the spine (AUC=0.71; p=0.81). CONCLUSION: mP(alpha) yielded a robust measure of trabecular bone microarchitecture for HR-MR images of the radius, which significantly improved the diagnostic performance in differentiating postmenopausal women with and without osteoporotic spine fractures compared with standard 2D bone histomorphometric parameters. This 3D characterization of trabecular microarchitecture may provide a new approach to better assess the strength of human cancellous bone using HR-MR image data.

Aged↗
PubMed2004

Mini-open approach combined with percutaneous transarticular screw fixation for C1-C2 fusion.

This paper describes a limited exposure for posterior C1-C2 arthrodesis aided by percutaneous transarticular fixation. The purpose of this study was to report the fusion rate using the aforementioned method. Fifty-seven patients (54 females and three males) with C1-C2 instability due to rheumatoid disease constituted the material of this study. The exposure was restricted to C0-C3 levels. The drilling and insertion of the screws was done through two mini stab wounds. A special sleeve and screwdriver were developed to facilitate this step. An autogenous iliac bone graft was fixed between the decorticated posterior arch of the atlas and the lamina of the axis vertebra. The mean of the atlantodental interval decreased from 8.5 mm (SD 2.3 mm) to 2.6 mm (SD 0.6 mm) at the immediate postoperative periods and reached 2.7 mm (SD 0.7 mm) after a mean follow-up of 30.4 months (SD 5.6 months). Malposition of the screws was observed in two patients and warranted a second operation in one. Fusion was evident in 98% of the cases. Percutaneous insertion of the screws in posterior C1-C2 transarticular fixation reduces the size of the exposure and the surgical trauma to the cervical segments below the fixation.

Adult↗
PubMed2004

A less invasive approach technique for operative treatment of lumbar canal stenosis. Technique and preliminary results.

UNLABELLED: The aim of this prospective study is to evaluate the efficacy of a less invasive approach for the operative treatment of lumbar canal stenosis. Using transmuscular dilatation this technique minimises surgical trauma. Through a working channel with a 11 mm outer diameter and under operative microscope guidance, decompression of the neural elements can be achieved. MATERIAL AND METHODS: From November 1998 to December 2001 38 consecutive patients with a mean age of 73.2 years were operated upon using this technique. The study included 56 lumbar segments. The mean follow up was 32 (18-55) months. The Visual Analogue Scale (VAS) for back and leg pain together with the Oxford Claudication Score (OCS) were used to assess the functional results. RESULTS: The average operating time for one level decompression was 74 minutes and the average blood loss was 32 ml/patient. Two patients (5.2 %) required revision by open surgery. The OCS improved from 29.4 preoperatively to 16.9 postoperatively (p < 0.001). VAS for back pain and leg pain also showed a significant improvement (p < 0.001). CONCLUSIONS: This less invasive approach is effective in decompressing lumbar canal stenosis. It has the advantage of early mobilisation and a short hospital stay, especially in elderly patients (mean age here: 73.2 years).

Aged↗
PubMed2003

A new minimally invasive posterior approach for the treatment of cervical radiculopathy and myelopathy: surgical technique and preliminary results.

Degenerative cervical disorders predominantly lead to anterior spinal cord compression (by bony spurs at the posterior margin of the vertebral body or by degenerated disc), which may be central and/or foraminal. In a smaller percentage of cases, there is encroachment of the canal mainly from posterior by bulging yellow ligaments or bony appositions, resulting in compression syndromes of roots or spinal cord. The aim of this work is to present a minimally invasive posterior approach avoiding detachment of muscles for the treatment of cervical radiculopathy and myelopathy. Thirteen patients suffering from cervical radiculopathy (four patients) or myelopathy (nine patients) were operated according to this technique. In principle, the technique secures access to the diseased spinal segment via a percutaneously placed working channel (11 mm outer diameter and 9 mm inner diameter). The cervical paraspinal muscles are not deflected, but just spread between their fibres by special dilators. All further steps are performed through this channel under control of three-dimensional vision through the operating microscope. The mean follow-up period was 17 months (one patient died 9 months postoperatively), and patients were evaluated using a modified version of the Oswestry Index, called the Neck Disability Index (NDI), and the visual analogue scale (VAS) for neck and arm pain. The mean NDI (P<0.0001) improved from 13.2 (preoperatively) to 4.8 (postoperatively). The VAS for arm pain (P<0.001) and for neck pain (P<0.001) also showed marked postoperative improvement. Complete recovery of the preoperative neurological deficit was found in four patients, while the remaining eight patients showed improvement of the neurological symptoms during the follow-up period. There were no intra-operative or postoperative complications and no re-operation. The preliminary experience with this technique, and the good clinical outcome, seem to promise that this minimally invasive technique is a valid alternative to the conventional open exposure for treatment of lateral disc prolapses, foraminal bony stenosis and central posterior ligamentous stenosis of the cervical spine.

Adult↗
PubMed2003

Long-term noninvasive ventilation in children and adolescents with neuromuscular disorders.

The aim of the current study was to investigate the long-term impact of nocturnal noninvasive (positive-pressure) ventilation (NIV) on sleep, sleep-disordered breathing (SDB) and respiratory function in children and adolescents with progressive neuromuscular disorders (NMD). Thirty patients (12.3 +/- 4.1 yrs) with various inherited NMD were treated with NIV for ventilatory insufficiency (n=14) or symptomatic SDB (n=16). Patients were prospectively followed with sleep studies, spirometry and peak inspiratory muscle pressure. Ten patients were studied before and after 3 nights withdrawal from NIV. NIV normalised nocturnal gas exchange in all patients and diurnal gas exchange in patients with ventilatory insufficiency. The effects persisted over 25.3 +/- 12.7 months. Nocturnal transcutaneous partial pressure of carbon dioxide improved from (baseline versus latest control) 7.1 +/- 1.3 to 5.5 +/- 0.6 kPa (53.7 +/- 9.9 to 41.6 +/- 4.8 mmHg), diurnal carbon dioxide arterial tension from 6.3 +/- 1.6 to 5.4 +/- 0.5 kPa (47.5 +/- 11.9 to 40.6 +/- 3.6 mmHg). NIV improved respiratory disturbance index, arousals from sleep, nocturnal heart rate and sleep architecture. Vital capacity decreased in five adolescents with Duchenne muscular dystrophy -183 +/- 111 mL x yr(-1) but remained stable in 25 children with other conditions (8 +/- 78 mL x yr(-1)). Three nights withdrawal of NIV in 10 previously stable patients resulted in prompt deterioration of SDB and gas exchange back to baseline but could be instantly normalised by resumption of NIV. Noninvasive (positive-pressure) ventilation has favourable long-term impact on nocturnal and diurnal gas exchange and sleep and in patients with non-Duchenne neuromuscular disorders on vital capacity as well. It is indicated in children and adolescents with symptomatic sleep-disordered breathing or ventilatory insufficiency due to neuromuscular disorders.

Adolescent↗
PubMed1986

Immunofluorescent localization of type-V collagen as a fibrillar component of the interstitial connective tissue of human oral mucosa, artery and liver.

Polyclonal antibodies against native human type-V collagen were produced in rabbits and goats. Following purification, crossreaction of the antibodies with highly immunogenic peptides of basement membranes or the interstitial matrix was excluded on the basis of sensitive radioimmunoassays. These antibodies, when applied to cryostat sections of human oral mucosa, liver and arterial walls, never stained basement membranes as did antibodies against type-IV collagen or laminin. On the contrary, we observed delicate arborizing fibers in the interstitial compartment with extensions contacting structures such as subepidermal basement membranes. Arterioles contained a unilamellar sheath of longitudinally oriented fibers limited to the intimal layer. Larger arteries exhibited a multilamellar fibrous fluorescence over the whole intima, whereas the media showed a much weaker staining. The data identified type-V collagen as an interstitial fibrillar collagen rather than a basement membrane collagen, with a tissue pattern completely different from that of collagens types I, III, VI or fibronectin. A reinterpretation of the role of type-V collagen in connective tissue function is warranted.

Antibody Specificity↗
PubMedDate not supplied

Acute ascending motoric paraplegia following intrathecal chemotherapy for treatment of acute lymphoblastic leukemia in children: case reports and review of the literature.

Severe side effects of chemotherapy in pediatric patients with acute lymphoblastic leukemia are rare, but well-known. We present two pediatric patients who developed ascending motoric paraplegia (AMP) following intrathecal chemotherapy. Both patients suffered from progressive weakness of their lower extremities, neurogenic bladder dysfunction, autonomous neural dysregulation and minor sensory deficits. Despite an initially similar clinical picture, progression and outcome were fairly different. There is convincing evidence that AMP is caused by spinal cord toxicity of intrathecally applied toxic agents such as cytarabin and/or methotrexate leading to spinal demyelinisation as demonstrated by elevated myelin basic protein in cerebrospinal fluid.

Acute Disease↗
PubMedDate not supplied

Surgical options in the treatment of the spinal disorders in ankylosing spondylitis.

Serious complications or unsatisfactory results in the past often have made patients as well as doctors hesitant to decide for surgery in ankylosing spondylitis. Though the techniques of correction for fixed flexion deformity still are demanding, decisive progress has been made toward less complications, less operative trauma and better quality of life after surgery. The present work represents a short review of the evolution of surgical techniques in treatment of spinal disorders encountered in ankylosing spondylitis. Emphasis is given to the benefits of improved instrumentation systems, intraoperative navigation, spinal cord monitoring and endoscopic surgery done in the prone position in completing the circumferential osteotomy of the thoracolumbar and lumbar spine in a safe and successful way. Fifty patients with deformities in the lumbar and thoracolumbar spine and 34 with deformities in the cervical spine were treated by instrumented corrective osteotomies. Excellent correction of the disturbed sagittal profile with restoration of a horizontal axis of vision was achieved in all of them. Neurological deterioration occurred in seven patients and was completely reversible in five of them.

Adult↗