3D soft tissue imaging with a mobile C-arm.

We introduce a clinical prototype for 3D soft tissue imaging to support surgical or interventional procedures based on a mobile C-arm. An overview of required methods and materials is followed by first clinical images of animals and human patients including dosimetry. The mobility and flexibility of 3D C-arms gives free access to the patient and therefore avoids relocation of the patient between imaging and surgical intervention. Image fusion with diagnostic data (MRI, CT, PET) is demonstrated and promising applications for brachytherapy, RFTT and others are discussed.     

When should the doctor order a spine X-ray? Identifying vertebral fractures for osteoporosis care: results from the European Prospective Osteoporosis Study (EPOS).

Vertebral fractures are common but usually remain unrecognized in primary care. Data from 2908 women and 2653 men in the EPOS study were used to derive algorithms to indicate the need for a spine X-ray to identify a fracture using easily elicited determinants. At a sensitivity of 50% for identifying cases, the specificity was increased from 50% to 78% in women and from 50% to 72% in men compared with a random allocation of X-rays. Use of X-rays can be optimized by selecting patients at high risk using a short screening procedure. INTRODUCTION: Previous osteoporotic fracture is an independent risk factor for further fractures and an indication for treatment. Vertebral fractures are the most common osteoporotic fractures before age 75, accounting for 48% of all fractures in men and 39% in women over 50. They usually remain unrecognized, so many patients requiring treatment are denied it, doubling their risk of a further fracture. Our objective was to develop an efficient algorithm indicating the need for an X-ray. MATERIALS AND METHODS: Data from 2908 women and 2653 men >or=50 years of age in the European Prospective Osteoporosis Study (EPOS) were analyzed. Lateral thoracic and lumbar spine radiographs were taken at baseline and at an average of 3.8 years later. Prevalent fractures were qualitatively diagnosed by an experienced radiologist. Fracture risk was modeled as a function of age, statural height loss since age 25, gender, and fracture history including limb fractures in the last 3 years using negative binomial regression. Receiver operating characteristic (ROC) curves were used to summarize a model's predictive ability, and a prediction algorithm was devised to identify those most likely to have a fracture. RESULTS: In a multivariate model for women, the risk of prevalent vertebral fracture significantly increased with age (RR, 1.67 [95% CI, 1.46, 1.93] per decade), statural height loss (1.06, [1.03, 1.10] per centimeter decrease), self-reported history of spine fracture (7.52 [5.52, 10.23]), and history of other major fracture (1.83 [1.46, 2.28]). Higher body weight reduced risk (0.86 [0.79, 0.95] per 10-kg increase). In men, the respective RR estimates were as follows: age (1.32 [1.18, 1.49]); height loss (1.06 [1.04, 1.09]); self-reported spine fracture (5.05 [3.69, 6.90]); other major fracture (1.42 [1.12, 1.81]); and weight (0.86 [0.79, 0.94]). Using algorithms based on these easily elicited determinants, specificity was increased from 50% to 78% in women and from 50% to 72% in men at a sensitivity of 50% compared with a random allocation of X-rays. At a sensitivity of 75%, the specificity was 50% in women and 40% in men. Inclusion of hip BMD (femoral neck or trochanter), measured in 1360 women and 1046 men, significantly improved the area under the ROC curves by 4% in women (p < 0.002) but not in men (p > 0.350). Spine BMD, measured in 982 women and 847 men, produced a significant 5% AUC improvement in women (p = 0.007) but not in men (p = 0.554). CONCLUSION: A woman 65 years of age with one vertebral fracture has a one in four chance of another fracture over 5 years, which can be reduced to one in eight by treatment. Positive treatment decisions are often contingent on identifying a vertebral fracture. Selective use of lateral vertebral X-rays can be optimized using a 2-minute screening procedure administered by a nurse.     

Mutations in the tyrosine kinase domain of the EGFR gene are rare in synovial sarcoma.

The prognosis of patients with synovial sarcomas is poor. New therapeutic strategies, such as target inhibition of the tyrosine kinase activity of the epidermal growth factor receptor (EGFR) with erlotinib and gefinitib, could be effective, because most synovial sarcomas overexpress this protein. In lung cancer, the responsiveness to gefinitib is strongly related to the presence of mutations in the tyrosine kinase domain of the EGFR gene, while erlotinib sensitivity seems to be partly linked to chromosome 7 polysomy or gene amplification. To clarify the role of EGFR in synovial sarcoma and to explore the potential for a targeted therapy approach, we have examined 13 of these soft tissue tumors. We have analyzed the EGFR expression by immunohistochemistry, searched for polysomy and gene amplification with fluorescence in situ hybridization (FISH) and screened for EGFR mutations in exons 18-21 using PCR and direct sequencing. All 13 tumors showed strong diffuse or focal EGFR expression. No amplifications of the EGFR gene were found. In contrast, several point mutations were identified in exons 18-21 of two synovial sarcomas. Whereas one of these tumors carried only a synonymous mutation, two missense mutations in exons 19 and 21 of the EGFR gene (P733S and A840 T, respectively) could be demonstrated in the second sample. In conclusion, strong EGFR expression in synovial sarcomas is not related to gene amplification. The existence of mutations in the tyrosine kinase domain of the EGFR gene in a small subset of synovial sarcomas suggests that only few patients may profit from the tyrosine kinase inhibitor therapy.     

The functional long-term results after bilateral sagittal split osteotomy (BSSO) with and without a condylar positioning device.

PURPOSE: The goal of this retrospective study was to examine whether utilization of condylar positioning devices in bilateral sagittal split osteotomy leads to long-term benefits for temporomandibular joint function as compared with the manual positioning technique. PATIENTS AND METHODS: The joint function of 49 patients (98 joints) who underwent bilateral sagittal split osteotomy or bimaxillary osteotomy at the University Hospital of Aachen between 1993 and 2003 was analyzed by recording joint movements with axiography supported by clinical examination of the temporomandibular joint. In 10 patients out of 28 with mandibular advancement and in 10 out of 21 with mandibular setback the Luhr positioning device was used intraoperatively to reproduce the condylar position. The joints of the remaining patients were positioned manually. The received data were statistically evaluated by using unrelated t test at P = .05. RESULTS: In mandibular advancement the manually positioned group showed significantly less signs of temporomandibular disorders, while there were slight advantages in axiographically measured joint track lengths for the patients who were operated with positioning devices. After mandibular setback surgery clinical analysis as well as axiography presented comparable results in both groups. CONCLUSION: The use of a positioning device did not provide a better functional outcome long term in either mandibular advancement or setback surgery. With the manual positioning technique, an at least equally good temporomandibular joint function was attained.     

URODILATIN (INN: ULARITIDE) AS A NEW DRUG FOR THE THERAPY OF ACUTE RENAL FAILURE FOLLOWING CARDIAC SURGERY

1. Acute renal failure is a severe complication following major cardiac surgery. 2. The effects of urodilatin were evaluated in a randomized, double-blind trial in patients suffering from incipient acute renal failure following cardiac surgery. 3. In the urodilatin group (n= 7) acute renal failure was reverted, whereas in the placebo group (n= 7) six patients had to be haemofiltered or haemodialysed (P < 0.005). 4. Urodilatin induced a rapid onset of diuresis in contrast to placebo-treated patients, who remained oliguric. 5. In the placebo group four of seven patients died while still on haemodialysis (mortality rate 57.1 %) during a postoperative follow-up period of 60 days, while all patients treated with urodilatin survived. 6. On the basis of these results it would appear that urodilatin is an effective drug for the treatment of incipient oliguric acute renal failure following cardiac surgery and for avoiding haemodialysis/haemoflltration.     

Acetylsalicylic acid—inducer of cytochrome P-450 2E1?

Pretreatment of rats with acetylsalicylic acid or sodium salicylate stimulates the metabolism of dichloromethane to carbon monoxide as measured by the carboxyhemoglobin level in blood. Simultaneous administration of dichloromethane and acetylsalicylic acid or sodium salicylate, respectively, was accompanied by reduced carboxyhemoglobin formation. In liver microsomes of rats pretreated with acetylsalicylic acid thep-nitrophenol hydroxylase activity was increased. It is concluded that (i) cytochrome P-450 2E1 is involved in the metabolic conversion of both dichloromethane and salicylic acid, and (ii) salicylic acid may be an inducer of cytochrome P-450 2E1.