Dosimetric analysis of the use of CBCT in diagnostic radiology: sinus and middle ear.

The use of cone beam computed tomography (CBCT) in diagnostic radiology departments is increasing. Several discussions arise whether with the CBCT application, some multi-slice CT (MSCT) examinations can be replaced by it. High hopes are set regarding the dosimetric aspects of CBCT: are patient doses in between those of conventional X-rays and MSCT? In this study, effective dose and organ doses were evaluated for two non-dental CBCT examinations: sinus and middle ear. A comparison with the dose obtained with a MSCT protocol was performed. Moreover, the sinus examination was also compared with the dose obtained by projection radiography (RX). Effective doses were estimated from thermoluminescent detector dose measurements in an anthropomorphic phantom and were compared against Monte Carlo simulations. Results show that the effective dose for the sinus examination is more than three times higher with MSCT than with CBCT and about five times lower with RX compared with CBCT, whereas for the middle ear examination, the effective dose obtained with MSCT is almost six times higher than that of CBCT. Finally, a sensitivity study on the size and position of the CBCT field of view showed the influence of these two factors on the dose received by the patient.

The efficacy of a polyhydrated ionogen impregnated dressing in the treatment of recalcitrant diabetic foot ulcers: a multi-centre pilot study.

OBJECTIVE: Assessing the efficacy of a polyhydrated ionogen impregnated dressing in the treatment of recalcitrant diabetic foot ulcers. SUMMARY BACKGROUND DATA: Diabetic Foot Ulcers (DFU) continue to present a formidable challenge in terms of morbidity and health care costs. Increasing evidence ascertains the important role of Matrix MetalloProteinases (MMPs) and their tissue inhibitors, TIMPs, in wound healing. Imbalance of MMPs in the DFU microenvironment has been associated with poor wound healing. Current research is directed towards therapeutic agents that could redress the imbalance of MMPs/TIMPs. Poly Hydrated Ionogen (PHI) formulation is based on metallic ions and citric acid. PHI application aims to positively restore MMP ratios within chronic wounds. This initial multi-centre pilot study aimed to investigate the efficacy of the PHI formulation in achieving stable wound closure in recalcitrant DFUs. MATERIAL AND METHODS: Twenty patients with therapy resistant DFUs of at least 1 cm2 and 3 months duration were treated with PHI formulation in an acetate carrier dressing. Wound debridement, digital imaging and wound perimeter tracing was performed weekly. Off-loading was performed by the use of appropriate shoe-wear (cut-out sandals) and crutches. Patient satisfaction was assessed with a questionnaire. A detailed evaluation sheet was kept for every patient and updated at each visit. RESULTS: Stable wound closure with high patient satisfaction was achieved in 16 (80%) DFUs. The mean time to full closure was 18 weeks. A stable wound epithelization was seen in all full closure patients up to latest follow-up of one year. CONCLUSIONS: Encouraging results of this pilot study prompt us to further investigate the PHI efficacy in DFU treatment in a multi-centre, randomized controlled trial.

Evaluation of the diagnostic value of a computed radiography system by comparison of digital hard copy images with screen-film mammography: results of a prospective clinical trial.

The purpose of the study was to determine prospectively the diagnostic value of a computed radiography (CR) system by comparing mammographic hard copy images with screen-film mammography (SFM). A series of 100 patients, who came for diagnostic investigation, underwent two-view SFM (Lorad M-IV Platinum) and digital mammography with a CR system (AGFA CR system). The images were obtained by double exposure, i.e. same view without removing compression of the corresponding breast. The CR images were processed with dedicated processing for mammography. Six radiologists read sets of SFM and CR images. The primary efficacy parameter was the overall diagnostic value. The secondary efficacy parameters were lesion conspicuity and lesion details (for masses and micro-calcifications), tissue visibility at chest wall and at skin line, axillary details, overall density and sharpness impression and the overall noise impression. These parameters were scored by a 7-point scoring system. "CR non-inferior to SFM" was concluded if the lower confidence interval bound exceeded 80%. The confidence interval for the overall diagnostic value was between 96.4% and 100%. Pooled analysis of the ten features for image quality comparison demonstrated for all but one feature (lesion details of the calcifications) CR non-inferiority to SFM.

Image quality measurements and metrics in full field digital mammography: an overview.

This paper gives an overview of test procedures developed to assess the performance of full field digital mammography systems. We make a distinction between tests of the individual components of the imaging chain and global system tests. Most tests are not yet fully standardised. Where possible, we illustrate the test methodologies on a selenium flat-panel system.

Laparoscopic pyloric exclusion after endoscopic retrograde cholangiopancreatography perforation.

We describe a laparoscopic technique of pyloric exclusion with gastroenterostomy and common bile duct T tube insertion for obvious perforation at endoscopic retrograde cholangiopancreatography with papillotomy. The patient was operated on immediately after diagnosis of the lesion. The postoperative sequellae were very comparable to those of elective laparoscopic common bile duct exploration. We believe this approach is interesting, especially in the current era of frequent litigation.

Laparoscopic inflatable band with Roux-en-Y gastric bypass.

BACKGROUND: Roux-en-Y gastric bypass (RYGBP) leaves a large blind gastric segment, which is inaccessible for conventional endoscopy. METHOD: A case is reported, describing a variation of laparoscopic RYGBP by partitioning the stomach by an inflatable band rather than by stapling or division. RESULTS: The stomach was partitioned into a proximal 15 cc pouch and a distal part by an adjustable gastric band. A RYGBP was fashioned from the proximal pouch. 9 patients were treated with this technique: 7 as an initial procedure and 2 after previous gastric banding which had been followed by insufficient weight loss. 1 of these latter patients developed erosion of the band through the gastrojejunostomy 7 months postoperatively. CONCLUSION: Laparoscopic proximal RYGBP with inflatable-band gastric partitioning is feasible. Erosion of the band though the gastrojejunostomy, however, might be a serious side-effect of this technique.

Confrontation of mammography systems in flanders with the European Guidelines for Quality Assurance in mammography screening. Analysis of initial results.

From May 1997 to April 98, 30 radiological centers made an agreement with the Leuvens Universitair Centrum voor Kankerpreventie (LUCK) for the work out of physical and technical quality control in mammography screening. A protocol was used based on the European Guidelines for Quality Assurance. The reports of all 30 acceptance tests were retrospectively reviewed. The following parts showed to be most critical: alignment of radiation field and film in the bucky, tube voltage precision, automatic exposure controller, average optical density of a standard exposure, dark room and its safe lights. The mean film gradient was in the majority of the centers higher than what is prescribed in the European document. This is acceptable and even desirable whenever daily quality control shows that the development system is sufficiently stable. Although it is difficult to compare the scores for the specific tests with results in other countries, there is evidence that the tendencies are very similar.