Vasovasostomy in dogs using the carbon dioxide milliwatt laser: Part II.

This is the second study of a two-prong investigation conducted to learn two different aspects of vasovasostomy in dog vas deferens by using the carbon dioxide milliwatt laser. This investigation involves the evaluation of patency and analysis of sperm. Six dogs underwent vasectomy, followed by vasovasostomies performed between 4 and 12 weeks later, utilizing two approximating sutures and welding with the carbon dioxide milliwatt laser. Metal clips were used both for x-ray analysis and localization of the vasovasostomy site. All dogs had pre-vasectomy semen analysis. Following vasectomy each dog underwent ejaculation until azoospermia was obtained. Vasovasostomy was performed and semen was examined. Prior to harvesting, vasography was also obtained. All ejaculates had active sperm noted and 12 of 12 vasograms (100%) revealed patency. The dogs were sacrificed at 4 weeks, 6 weeks, and 8 weeks post-vasovasostomy. The vasovasostomy specimens were studied with electron microscopy and by histological evaluation. The vasovasostomy was completed in under 90 minutes by using this laser-assisted technique. This procedure offers to the urologist a more simplified and reproducible operation that can be performed easily and with a potential decrease in hospital costs.

Carbon dioxide milliwatt laser in the vasovasostomy of vas deferens in dogs: Part I.

This is the first arm of a two prong study conducted to learn two different aspects of vasovasostomy in dog vas deferens using the milliwatt carbon dioxide laser. The first study involved the evaluation of patency without collection of sperm. Six dogs were evaluated and all underwent vasectomy and subsequently had vasovasostomies performed between 4 and 12 weeks utilizing two approximating sutures and welding with the milliwatt carbon dioxide laser. Metal clips were used for both X-ray analysis and localization of the vasovasostomy site. In this investigation a vasogram was performed. Dogs were sacrificed at 4, 6, and 8 weeks postvasovasostomy. The vasovasostomy specimens were studied with electron microscopy and histological evaluation. The vasovasostomy was completed in under 120 minutes using this laser-assisted technique and was found to be a viable and promising technique for vasovasostomy.

Metastatic carcinoma of the prostate presenting radiographically as lymphoma.

Anterior mediastinal and retroperitoneal lymphadenopathy is rarely clinically evident in patients with metastatic carcinoma of the prostate. We report a case in which the nodal disease was suggestive of the diagnosis of malignant lymphoma. Immunohistochemical stain for prostate specific antigen was useful in assuring the diagnosis.

The effects of kilovoltage on diagnostic accuracy in chest radiography.

Chest examinations, consisting of three posteroanterior chest radiographs obtained at 75,120, and 140 kVp, were performed on patients with clinically suspected pulmonary disease. The 66 sets of radiographs included 23 lung cancers, 13 other clinically relevant abnormalities, and 27 normals. All findings were verified by clinical or radiologic follow-up except for three cases that could not be verified and were excluded from later analysis. Six radiologists viewed the series of 198 radiographs one at a time in a randomized sequence. They scored each radiograph and each suspected abnormality with a confidence rating from 1 (normal) to 4 (definitely abnormal). Based on these scores receiver operating characteristic (ROC) curves were plotted for each set of kVp settings. The results indicated that higher kVp values improved diagnostic accuracy. Analysis of the ROC curves showed statistically significant differences between 140 kVp and both 120 kVp and 75 kVp, but not between the two lower kVp values.