Suphaneewan Jaovisidha

Fibrolipomatous hamartoma : MR imaging findings

ObjectiveTo analyze the MR imaging features of fibrolipomatous hamartoma (FLH) of nerves.Design and patientsMR imaging studies from six patients (three men and three women) were retrospectively reviewed by three musculo-skeletal radiologists. In four patients, a biopsy of the nerve lesion was performed. In two patients, biopsy data were unavailable and the diagnosis was based on the clinical history combined with the MR imaging findings.Results and conclusionMR imaging demonstrated fusiform nerve enlargement that was caused by fatty proliferation and thickening of nerve bundles. Nerve bundles appeared as serpentine tubular structures, hypoin-tense on both T1- and T2-weighted images. The degree of fatty proliferation varied among patients. In addition, significant variation in the distribution of fat along the course of the nerves was noted. In three patients, FLH followed the branching pattern of the nerves, a characteristic pathologic finding. In two patients, intramuscular fat deposition (biceps and tibialis posterior muscles) was present. MR imaging findings of FLH are typical, allowing a confident diagnosis. The variation of fatty proliferation among patients and involved nerves as well as the tendency of the abnormalities to follow the branching pattern of the nerves is well demonstrated with MR imaging. FLH may present as an isolated nerve lesion, may be associated with intramuscular fat deposition, or may occur as a feature of macrodystrophia lipomatosa (MDL).

Hemophilic pseudotumor: spectrum of MR findings

Abstract Objective. To determine the MR imaging appearance of hemophilic pseudotumor (HP) and its clinical implications. Design and patients. Five hemophilic patients (aged 35–77 years) with 12 HPs in various anatomic locations were included in this study. The MR images were retrospectively evaluated for the appearance of the lesions and accompanying abnormalities, as well as their clinical implications. Results and conclusion. MR images of all five patients (12 lesions) showed well-defined masses containing blood clots in various stages of organization surrounded by a fibrous capsule in subcutaneous fat or in intramuscular, interfascial, subperiosteal, and intraosseous locations. Intramuscular HP frequently had mural nodules. This is an almost unique appearance that is somewhat unexpected. MR imaging allowed determination of number, size, and extent of the lesions, evidence of neurovascular involvement, and accompanying musculoskeletal alterations. It is concluded that MR imaging not only is a sensitive and accurate method for detecting and diagnosing HP and providing useful information for therapeutic decision making, but can also be used to assess results of treatment by allowing evaluation of the evolution of blood products, the size of lesions in regions difficult to access by physical examination, and recurrent bleeding within a chronic lesion.

Influence of Spondylopathy on Bone Densitometry Using Dual Energy X-Ray Absorptiometry

Abstract. Spinal cord injury (SCI), as well as other neuromuscular disorders, not only results in osteopenia but also induces various patterns of osseous, articular, and soft tissue alterations. In the spinal column, a variety of abnormalities occur. To evaluate the magnitude of discrepancy of bone densitometry results caused by spondylopathy in SCI patients, we analyzed anteroposterior (AP) radiographs of the lumbar spine [obtained within 1 month of dual energy X-ray absorptiometry (DXA)] in 116 SCI patients for various manifestations of spondylopathy, and matched the result to each vertebral level (L1, 2, 3, 4). The dataset was stratified by individual vertebra (totally 463 vertebrae) as valid (no demonstrable other abnormal density on plain radiograph except osteopenia), abnormal without, and abnormal with hardware. The influence of spondylopathy on bone densitometry results was determined by the analysis of variance (ANOVA) and post hoc analysis. Our results showed that 227 (49%) vertebrae were abnormal. Significant elevation (15%, 15%, 18%, 20%; P < 0.001–P < 0.05) of bone mineral density (BMD; g/cm2) was observed at all levels (L1, 2, 3, 4, respectively), particularly at those abnormal vertebrae without hardware compared with valid (no other abnormal density on radiograph except osteopenia (Table 1). The L4 level was most severely affected. We concluded that in SCI patients, owing to various secondary progressive skeletal abnormalities, particularly neuropathic spondylopathy, can have strongly and significantly elevated vertebral bone densitometry results, which can obscure underlying osteoporosis, leading to misinterpretation and underestimation of fracture risk. DXA, although characterized by improving spatial resolution, cannot replace radiography in establishing the magnitude of this skeletal pathology. Therefore, determination of bone density in this region with corresponding plain radiographs is highly recommended.

Influence of heterotopic ossification of the hip on bone densitometry: a study in spinal cord injured patients.

Objective: To evaluate (1) the magnitude of falsely elevated bone density results caused by heterotopic ossification (HO) around the hip and (2) effect of age of patients when the measurement was taken, age of patients at injury, and age of injury (time since event) to the prevalence of HO. Subjects and methods: We blindly analyzed plain radiographs of the hip [(obtained within 1 month of dual energy X-ray absorptiometry (DEXA)] in 107 spinal cord injured (SCI) patients for HO and matched the result to the three regions of interest (ROI): the femoral neck, Wards triangle, and the trochanter. The influence of HO on bone densitometric values was determined by the analysis of variance (ANOVA) and post-hoc analysis. Results: Nineteen (18%) patients had HO; overlying the femoral neck (79%), trochanter (74%) and Wards triangle (37%), respectively. Significant elevation of densitometric values (P<0.05 or less) was observed in a various magnitude at each ROI, with the greatest elevation at Wards triangle. The prevalence of HO was high when the patients were injured at age range of 20–39 years. Conclusions: HO around the hip can cause significantly elevated bone densitometry results at all ROIs, which can obscure underlying osteoporosis, leading to underestimation of fracture risk. Determination of bone density in this region with corresponding plain radiographs would be of help. In SCI patients, prevalence of HO was high when the age of patients at injury was 20–39 years.

Myositis ossificans of the foot

A 37-year-old woman with myositis ossificans of the left foot is reported. A faint density was seen on foot radiographs, whereas computed tomography images showed a rim of mineralization inferior to the second and third metatarsal bones. On short tau inversion recovery-weighted magnetic resonance images, a hyperintense lesion was demonstrated with hyperintensity extending to the surrounding soft tissues. The rim of ossification appeared hypointense. Other non-neoplastic soft tissue processes with bone formation such as pseudomalignant osseous tumor of soft tissues, florid reactive periostitis, and bizarre parosteal osteochondromatous proliferation occur more commonly in the foot than myositis ossificans. A differential diagnosis of these lesions including periosteal and parosteal osteosarcoma, periosteal chondroma, and osteomyelitis is discussed.

The clinical efficacy of piroxicam fast-dissolving dosage form for postoperative pain control after simple lumbar spine surgery: a double-blinded randomized study.

Study Design. A prospective, randomized, double-blinded clinical trial was conducted. Objective. To study the efficacy of piroxicam fast-dissolving dosage form in reducing postoperative pain after simple lumbar spine surgery. Summary of Background Data. Many reports mention the use of nonsteroidal antiinflammatory drug for relieving postoperative pain, but study still is lacking on their use in spine surgery. Methods. For this study, 50 patients who underwent discectomy or one-level laminectomy were randomly sampled into two groups: 21 patients in the placebo control group and 29 patients in the study group. In addition to a normal postoperative analgesic regimen, each patient received placebo or piroxicam fast-dissolving dosage form (2 tablets administered sublingually 1 to 3 hours before surgery). This regimen was repeated with 2 tablets after 24 hours, then 1 tablet after 48 hours. Postoperative pain was evaluated every 6 hours by a visual analog scale for 3 days. The amount of morphine usage was measured on postoperative days 1, 2, and 3. Postoperative variables such as blood loss, length of wound, and time of operation also were recorded. Results. There was no difference between the groups with respect to age, weight, height, gender, and type of operation. The postoperative pain of the study group, as measured by visual analog scale, showed significant improvement (P < 0.05) during the postoperative period 12 to 42 hours after surgery. The study group used less morphine, but their usage showed no significant difference on postoperative days 1, 2, and 3. When the visual analog scale between the types of operation was compared, the scale for the discectomy group was better than that for the laminectomy group. The results of the postoperative variables showed no difference between the groups in terms of postoperative blood loss, length of wound, and time of operation. Conclusions. Sublingual administration of piroxicam fast-dissolving dosage form after simple spine surgery is effective and efficient in relief of postoperative pain. Because of its low side effects and high toleration, piroxicam fast-dissolving dosage form may be considered as an alternative for postoperative pain control during the early postoperative period.

IMAGING OF FUNGAL, VIRAL, AND PARASITIC MUSCULOSKELETAL AND SPINAL DISEASES

There are many nonbacterial infections that have musculoskeletal manifestations and radiologic findings. These infections produce a limited range of tissue responses, depending on the organism, the tissue compartment affected, and the immune competence of the host. Diagnosis is dependent on obtaining an appropriate travel or geographic history, the clinical and laboratory features, and on occasion the specific radiologic findings.

Morphometric evaluation of subaxial cervical spine using multi-detector computerized tomography (MD-CT) scan: the consideration for cervical pedicle screws fixation

BackgroundCervical pedicle screw (CPS) insertion is a technically demanding procedure. The quantitative understanding of cervical pedicle morphology, especially the narrowest part of cervical pedicle or isthmus, would minimize the risk of catastrophic damage to surrounding neurovascular structures and improve surgical outcome. The aim of this study was to investigate morphology and quantify cortical thickness of the cervical isthmus by using Multi-detector Computerized Tomography (MD-CT) scan.MethodsThe cervical CT scans were performed in 74 patients (37 males and 37 females) with 1-mm slice thickness and then retro-reconstructed into sagittal and coronal planes to measure various cervical parameters as follows: outer pedicle width (OPW), inner pedicle width (IPW), outer pedicle height (OPH), inner pedicle height (IPH), pedicle cortical thickness, pedicle sagittal angle (PSA), and pedicle transverse angle (PTA).ResultsTotal numbers of 740 pedicles were measured in this present study. The mean OPW and IPW significantly increased from C3 to C7 while the mean OPH and IPH of those showed non-significant difference between any measured levels. The medial-lateral cortical thickness was significantly smaller than the superior-inferior one. PTA in the upper cervical spine was significantly wider than the lower ones. The PSA changed from upward inclination at upper cervical spine to the downward inclination at lower cervical spine.ConclusionsThis study has demonstrated that cervical vertebra has relatively small and narrow inner pedicle canal with thick outer pedicle cortex and also shows a variable in pedicle width and inconsistent transverse angle. To enhance the safety of CPS insertion, the entry point and trajectories should be determined individually by using preoperative MD-CT scan and the inner pedicle width should be a key parameter to determine the screw dimensions.

A new case of maternal lupus-associated chondrodysplasia punctata with extensive spinal anomalies.

A New Case of Maternal Lupus-Associated Chondrodysplasia Punctata With Extensive Spinal Anomalies Thipwimol Tim-aroon, Suphaneewan Jaovisidha, and Duangrurdee Wattanasirichaigoon* Division of Medical Genetics, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand Department of Radiology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand

Unrecognized vertebral fractures in adolescents and young adults with thalassemia syndromes.

Osteoporosis is a common problem in thalassemics. As the most affected bone is spinal vertebrae, theoretically, it should have the greatest risk of fracture. However, vertebral fracture (VF) in thalassemics was rarely reported. Screening for asymptomatic VF in thalassemics has not been reported. We, therefore, evaluated prevalence of VF in adolescents and young adults with thalassemia. A total of 150 patients with thalassemia, aged 10 years and older were enrolled. Lateral thoracolumbar spine radiography was evaluated. Twenty patients (13%) had VF and 6 of 20 (30%) had multiple VFs. The 2 most common sites of VF were lumbar 1 and thoracic 12 vertebrae. Comparing with the group without VF, thalassemics with VF were older, had more severe degree of thalassemia, history of splenectomy and previous non-VF, more iron chelation use, and longer duration of blood transfusion, but had lower pretransfused hematocrit. Multivariate analysis revealed 2 predictive factors for VF, having severe thalassemia and aged 20 years or older (odds ratio 5.7 and 5.0, respectively). In conclusion, unrecognized asymptomatic VF in thalassemics was not uncommon. Risk factors associated with VF included severe thalassemia and age 20 years or older. Screening for VF in the high-risk patient should be considered.