Utility of Toe-brachial Index for Diagnosis of Peripheral Artery Disease

Abstract

Background: The ankle brachial pressure index (ABI) is a simple, useful method for diagnosing peripheral artery disease (PAD). Although the ABI is an objective diagnostic method, it has limited reliability in certain scenarios. The aim of the present study was to determine the accuracy and reliability of the toe brachial index (TBI) as a diagnostic tool for detecting stenosis in PAD, associated with normal or low ABI values.

Methods: ABI and TBI values were measured in 15 patients with diabetic gangrene who were suspected of having lower extremity arterial insufficiency. The ABI and TBI values were measured using a device that allowed the simultaneous measurement of systolic blood pressure in the upper and lower extremities. In addition, the ABI and TBI values were compared pre- and post-angiography.

Results: Patients with an ABI of 0.9-1.3 showed almost no difference between the 2 measurements. The patients with TBI >0.6 had no arterial insufficiency. The patients with TBI <0.6 required vascular intervention with ballooning. After the angiography, the gangrenous wounds decreased in size more rapidly than they did prior to the intervention.

Conclusions: Our findings suggest that TBI is the method of choice for evaluating lower limb perfusion disorders. This result requires further studies of TBI in a larger number of patients. Future long-term studies should therefore evaluate the utility of TBI as a means of screening for PAD and the present findings should be regarded as preliminary outcomes.

Keywords: Ankle brachial index; Peripheral arterial disease; Toe brachial index.

Conflict of interest statement

No potential conflict of interest relevant to this article was reported.

Figures

Fig. 1

Case 12 A 60-year-old female with diabetic gangrene. (A) Initial wound finding. Diabetic gangrene on left foot, lateral side. (B) Left foot wound 3 months later. The wound size was reduced.

Fig. 2

Cases 5, 6 (A) Initial toe brachial index (TBI) values. The right and left TBI were 0.31 and 0.63. (B) TBI values 3 months later. The values were elevated to 0.45 on the right and 0.66 on the left.

Fig. 3

Case 5 (A, B) Preintervention angiogram demonstrating complete occlusion of the distal peroneal artery and distal posterior tibial artery. Nearly total occlusion of the anterior tibial artery appeared on the angiogram. (C, D) Postintervention angiogram after vascular intervention by a balloon-expandable device.

Fig. 4

Clinical course of diabetic gangrene DM, diabetes mellitus; ABI, ankle brachial index; TBI, toe brachial index.