Role of rapid imprint cytology in the diagnosis of skin cancer and assessment of adequacy of excision.

Imprint cytotechnique was employed in 20 cases of maligant skin tumours (11 squamous cell carcinoma, 4 basal cell carcinoma and 5 malignant melanoma) to evaluate the reliability of the technique by comparing the results with histologic diagnosis. In ten cases margins of the excised tumours were also subjected to imprint and histopathologic studies to assess the clearance of malignancy. All the tumours were correctly diagnosed in imprint smears. Similarly 100% cytohistopathologic correlation was also obtained in the assessment of excisional margins of the tumours. The technique of imprint cytology may be employed for quick diagnosis of skin cancers and in assessment of clearance of surgical field during surgery.     

Experimental retinal branch vein occlusion in rhesus monkeys. III. Histopathological and electron microscopical studies.

Experimental retinal vein occlusion in monkeys was followed by an immediate increase in capillary permeability which was accompanied by retinal oedema. This functional capillary change was followed at about 6 hours after occlusion by structural damage to the capillary wall. Thrombus formation occurred in the damaged vessels, and areas of stasis were thus produced with associated retinal haemorrhages. Finally, there was complete loss of the capillary endothelium and pericytes, and the acellular capillaries were invaded by proliferating glial cell processes, so producing permanent capillary closure.     

theoretical considerations on the mechanism of the aqueous outflow

Two model systems for aqueous outflow across the trabecular wall of Schlemm's canal are considered assuming respectively: (i) vacuolar transport by ‘macropinocytosis’; and (ii) flow through permanent transcellular channels. The implications of each are compared.     

Posterior urethral valves: preliminary observations on the significance of plasma Renin activity as a prognostic marker

PURPOSE: A significant number of children with posterior urethral valves (PUVs) have chronic renal failure due to tubulointerstitial damage. Activation of the renin-angiotensin system is known to inflict this injury. We investigated the role of plasma renin activity (PRA) in patients with PUVs and sought to establish a relationship between renal damage and PRA. MATERIALS AND METHODS: The records of patients with PUVs were reviewed regarding the time of valve ablation, serum creatinine, scars, grade of reflux and glomerular filtration rate (GFR). PRA was measured before and after valve ablation. RESULTS: A total of 25 patients had PUVs (mean age 3.2 +/- 2.4 years, mean period of observation 4.5 +/- 1.2 years). Mean PRA was increased before valve ablation in all patients irrespective of age, and decreased after ablation. Of 25 patients 14 (56%) had renal damage, with a mean PRA of 36 +/- 4.5 ng/ml per hour compared to 26 +/- 8.2 ng/ml per hour in patients with normal renal function (chi-square 4.2 p = 0.01). Of the 14 patients with renal damage 9 (64%) had normal GFR at age 1 year but increased PRA. Of these 14 patients the accepted criteria for renal damage of increased serum creatinine, high grade reflux, scars and decreasing GFR were present in only 6 (43%), 3 (21%), 2 (14%) and 4 (29%), respectively. PRA was increased in all 14 cases. CONCLUSIONS: PRA was increased before valve ablation and decreased after ablation. It is increased in patients with early renal damage. Our preliminary observations indicate that PRA may be helpful in identifying patients with early renal damage.