Thoracic outlet syndrome: evaluation with CT

Diagnosis of the thoracic outlet syndrome is often difficult, particularly in patients without osseous abnormalities on plain radiographs. The radiographic and computed tomographic (CT) findings were reviewed from 27 patients with thoracic outlet syndrome and 21 normal subjects. The plain radiographs and CT scans were assessed by two independent observers without awareness of the clinical history. Fifteen patients with thoracic outlet syndrome had osseous abnormalities (anomalous cervical ribs; abnormally long, drooping C-7 transverse processes) identifiable on plain radiographs. CT did not provide further diagnostic information in the patients with abnormal radiographs. Eight of 12 patients (66%) with normal plain radiographs had abnormal findings on CT scans, consisting of impingement of the C-7 transverse process on the scalene triangle or anteromedial aspect of the middle scalene muscle. Only two of 21 control patients (9.5%) displayed this CT abnormality (P less than .01). CT may be useful in patients with symptoms suggestive of thoracic outlet syndrome and no osseous abnormalities on plain radiographs.     

The normal development of tibial torsion

Objective: Pathological rotation of the leg is a well-known problem in paediatric orthopaedics. In this study the normal development of tibial torsion during growth was evaluated by computed tomography (CT). Design: Seventy-eight normal individuals (52 children, 26 adults) aged 3–51 years were examined with CT. In axial scans the angle between a line tangential to the posterior part of the femoral condyles and the intermalleolar line, a line through the centre of the lateral and medial malleolus, was measured. The radiation exposure was evaluated and accepted by The National Department for Radiation and the Regional Committee for Ethics in Science. Results: CT showed that the average lateral torsion of the leg at the age of 4 years was 28° with an individual variation of 20°–37°. Later the increase in tibial torsion was on average 1°/year until 10 years of age and, thereafter, 4° until maturity when the mean lateral torsion was 38° (18°–47°). Conclusion: Tibial torsion in children mainly develops during the first 4 years of life. After this the increase was of less clinical significance. Received: 13 November 2000 Revision requested: 26 February 2001 Revision received: 19 March 2001 Accepted: 18 April 2001     

Histological characterization of a delayed wound healing model in pig

Chronic wounds, such as venous ulcers and pressure ulcers, frequently remain unresponsive to currently available treatments. Several animal models of wound healing have been published, including models of impaired healing developed to mimic the clinical condition of chronic wounds better. We used a delayed wound healing model in the pig that uses irradiation of the skin prior to creation of the surgical wounds and characterized it histologically. Radiation was used on one side of the back prior to making four full-thickness wounds on each side. Clinical observations were performed to record granulation tissue, reepithelialization, and wound area as a function of time. Histology data were obtained at 1, 2, 3, and 4 weeks, and slides were stained with hematoxylin and eosin for general observations. Immunohistochemistry was performed using laminin as a marker for blood vessels, and the number, size, and circularity of blood vessels found in the granulation tissue were measured. Our results show that this model causes a delay in wound healing that is mostly apparent between days 7 and 15. Granulation tissue took more time to form and fill the wounds on the irradiated side, and blood vessels were slower to develop. Blood vessels were larger and more irregular in shape on the irradiated side than on the control side. After 2 weeks, healing resumed, indicating that the induced damage was not irreversible. These results suggest that this model can be used to test the effects of therapeutic approaches intended to treat chronic wounds.     

Water-content calculation in growth plate and cartilage using MR T1-mapping design and validation of a new method in a porcine model

Objective

There is a close relation between cartilage health and its hydration state. Current magnetic resonance methods allow visualizing this tissue. However, a quantitative analysis is more useful when studying disease. The purpose of this study was to quantify water content in cartilage using magnetic resonance without contrast agents.

Materials and methods

Water-content estimations using T1 magnetic resonance mapping were done first in eight gelatin samples where the water content was previously known. The same method was used in the physeal areas of eight skeletally immature 30-kg pigs. To calculate accuracy, T1 calculations were compared to dry-freeze, which is considered the gold standard because it can remove the total water content form a tissue. Four fresh cartilage and seven gelatin samples were dry-frozen. Water content obtained from dry-freeze was compared to the one calculated from T1 map values. A mathematical model and statistical analysis were used to calculate the predictive value of the method and its significance.

Results

T1-map-based magnetic resonance method can calculate water content in cartilage with an accuracy of 97.3 %. We calculated a coefficient of variance for this method against dry-frozen sample of 3.68 (SD?=?1.2) in gelatin samples, and 2.73 (SD?=?1.3) in in vivo samples. Between two independent observers, the coefficient of variance was 0.053, which suggests it can be easily reproduced.

Conclusions

Magnetic resonance was able to calculate, with high accuracy, the cartilage water content using T1 mapping sequences.     

Lengthening of the tibia over an intramedullary nail, using the Ilizarov external fixator. Major complications and slow consolidation in 9 lengthenings.

We lengthened 9 tibial segments over a nail to reduce the time in the external fixator in 5 patients with constitutional shortness. The median lengthening was 7 (5.5-7.3) cm and the external Ilizarov frame was removed after median 99 (63-125) days. In spite of a short time in the external fixator, consolidation was slow, with a median lengthening index of 4.4 (2.4-6.1) months/cm. The procedure resulted in 3 fatigue fractures of the intramedullary nail or interlocking screws that needed revision and bone grafting. In 1 patient, a deep intramedullary infection occurred. After the experience of these major complications we have returned to the traditional callotasis lengthening method described by Ilizarov.     

Influenza pandemic: perception of risk and individual precautions in a general population. Cross sectional study

Background  

An influenza pandemic may have considerable impact on health and societal functioning. The aim of this study was to explore people's reflections on the consequences of a pandemic.     

Primary malignant melanoma of the cervix and review of the literature.

Primary malignant melanoma of the cervix was diagnosed in a patient presenting with postmenopausal bleeding. A cervical lesion was biopsied, and diagnosis was established by electron microscopy and staining procedures. After failing radiotherapy, the patient was treated with simple hysterectomy and bilateral salpingo-oophorectomy. The cytology, histology, and electron microscopy of this lesion are presented in addition to a clinical discussion.     

Short-term carcinogenicity testing of 2-amino-1-methyl-6-phenylimidazo[4, 5-b]pyridine (PhIP) and 2-amino-3-methylimidazo[4, 5-f]quinoline (IQ) in E{micro}-pim-1 transgenic mice

The usefulness of transgenic Eµ-pim-1 mice over-expressingthe pim-1 oncogene in lymphoid tissues, as sensitive test organismswas studied in a short-term carcinogenicity study. The micewere fed standard diet Altromin 1314 supplemented either with0.03% 2-amino-1-methyl-6-phenylimidazo[4, 5-b]pyridine (PhIP)for 7 months or with 0.03% 2-amino-3-methylimidazo[4, 5-f] quinoline(IQ) for 6 months. PhIP and IQ are heterocyclic amines formedduring cooking of meat and fish and are mutagenic to bacteriaand cultured mammalian cells. PhIP is a potent mouse lymphomagen,while IQ is a liver carcinogen and also causes lung tumors andtumors of the forestomach in mice. We found that transgenicEµ-pim-1 mice are highly susceptible to PhIP induced lymphomagenesisbut do not respond to the IQ treatment. PhIP feeding of Eµ-pim-1mice not only increased the total number of T-cell lymphomasbut also decreased the latency time compared to either transgenicor wild-type controls. The effect was most pronounced in thetreated female Eµ-pim-1 mice, which showed a higher incidenceof PhIP induced T-cell lymphomas than transgenic males and astrongly reduced latency period after PhIP treatment comparedto non-transgenic mice. Our results suggest that the transgenicEµ-pim-1 mouse may be a useful model for short-term carcinogenicityscreening of potential genotoxic carcinogens having the lymphoidsystem as target tissue. The carcinogen IQ which does not havethe lymphoid system as a target was not recognized in this model.