The 125I-labelled fibrinogen test has been used to assess the incidence of deep venous thrombosis in 88 patients who had undergone elective aorto-iliac reconstruction. Deep venous thrombosis was detected in 18 (20.5 per cent). The results suggest that these patients merit prophylaxis.

Simultaneous clearance of 99Tcm from the gastrocnemius and quadriceps muscles has been studied in 74 limbs of 62 patients with claudication and in 20 normal limbs of 15 volunteers. The local decay curve for 10 min at rest and for 20 min after a 3-min treadmill walk at 4.5 km/h was recorded. The changes in blood flow which occurred after exercise were characteristic of the arteriographic lesions and they explain the haemodynamics of claudication.

The effect of continuous i.v. infusion of pentoxifylline, administering 1,200 mg/24 hours through 15 days, was studied in 22 patients (19 m, 3 f) with arteriographically confirmed extensive occlusion in the femoro-popliteal segment, associated with marked intermittent claudication and rest pain of varying severity. The following parameters were used for the verification of the therapeutic response: Flow resistance factor (RF), pressure indices at rest (RPI) and after exercise (PPI) and recovery time (RT) assessed by means of ultrasonic Doppler technique; muscle and skin blood flow at rest and after exercise using 99m Technetium Clearance Technique (TC); toe skin temperature (TST) by electric thermometer; painfree walking distance (WD) assessed on treadmill (horizontal, 4 km/h); rest pain (RP) was assessed by a 4-step-relief-scale. There was an overall good response to treatment, the studied parameters showing the following changes: RF improved in 12/17 patients (= 70%); RT decreased in 14/22 patients (= 63%) RPI and PPI showed no change; TC (muscle) increased after exercise in 17/22 patients (= 77%); TC (skin) increased after exercise in 20/22 patients (= 90%); WD increased on average by 80% (from 115 m to 206 m); TS increased in 16 limbs; RP showed an overall relief. The results of this study indicate that the continuous infusion of pentoxifylline is safe and effective in improving the condition of patients with severe peripheral vascular disease.

The effect of oral pentoxifylline, administered 1,200 mg/day (400 mg slow-release tablets tid) through six weeks, was studied in 10 patients with established deep venous incompetence and persisting venous ulcers. The following parameters were used for verification of the therapeutic result: venous patency (VP) and valvular competence (VC) assessed by means of Doppler ultrasound; venous refilling time (VRT) assessed by photoplethysmography; skin blood flow (SBF) at rest and after tiptoeing exercise, as well as skin perfusion pressure (SPP), both assessed by means of 99mtechnetium clearance technique. Finally, photo documentation of the tissue lesion was obtained, using a two-dimensional (max and min diameter = Dmax, Dmin) metered scale photo. There was an overall good response to the treatment, the studied parameters showing the following changes: VP and VC remained unchanged; VRT improved in 8 patients, SBF increased in 10; SPP slightly improved in 5; and Dmax and Dmin in all 10 patients. Removal or substantial diminution of the ulcers was obtained in 8 patients. These findings indicate that oral administration of pentoxifylline over a period of six weeks supports the conservative treatment and improves considerably the condition of patients with persisting venous ulcers.

There has been no end to the attempts made to determine the site and severity of arterial lesions in claudicants by the use of non-invasive methods but, so far, their diagnostic value has been limited. A method whose diagnostic accuracy in determining the site and functional severity of the lesions approaches that of arteriography is discussed. The hyperaemic index, which is the ratio of the total excess of blood supply during post-exercise hyperaemia over the maximum hyperaemic flow, has been determined in the thigh and calf simultaneously, by measuring the 99Tcm muscle clearance in 30 limbs of 20 healthy volunteers and 139 limbs of 145 patients with claudication. Lumbar arteriography classified the lesions in all patients as 0-10 per cent, 10-40 per cent, 40-70 per cent and more than 70 per cent stenosis. A bivariate analysis of the hyperamic indices of the thigh and calf determined the site and whether single lesions consisted of a stenosis greater or less than 70 per cent. In limbs with combined aorto-iliac and superficial femoral lesions the values of the hyperaemic indices could determine which of the two lesions was the more severe in addition to whether lesions consisted of a stenosis greater or less than 70 per cent. These findings have been confirmed in a further blind prospective study of 47 limbs in which determination of the site and severity of lesions preceded aortography.