18F-FDG PET/CT Imaging of Critical Ischemia in the Diabetic Foot

Abstract

A 72-year-old patient with type 2 diabetes mellitus underwent F-FDG PET/CT for diabetic foot infection. No increased focal uptake was seen. F-FDG uptake was absent in the second, third, and fourth toes of the right foot. Angiography demonstrated severe stenosis in the proximal anterior tibial artery and segmental stenosis on the posterior tibial artery. The patient was diagnosed as having dry gangrene of the second to fourth toes of the right foot due to ischemia. He underwent a selective amputation because of the lack of revascularization possibilities.

Commentary: Myths and Proofs of Angiosome Applications in CLI: Where Do We Stand?

“…16 Specific microcirculatory evaluation can provide serviceable information about subcutaneous and tegumental foot perfusion (often misshaped by local wound characteristics) 18,27,31,36 and complete the macrocirculatory appraisal. 16,35 Miscellaneous methods, 35,[41][42][43] such as the transcutaneous oxygen pressure, 8,41 skin perfusion pressure 30,41 (also performed by Iida et al 10 ), tissue oxygen saturation mapping, 32 and the new group of molecular scintigraphic imaging techniques, 43,44 are available currently; these exams can provide valuable noninvasive microvascular (up to the molecular level) evaluation, 43,44 eventually by adding the angiosome orientation. 8,16,30,44 Interestingly, only a few publications regarding the importance of macro-and micro-circulation assessment in CLI are available in the literature 35 and even scarcer are observations about their specific investigation.…”

“…16,35 Miscellaneous methods, 35,[41][42][43] such as the transcutaneous oxygen pressure, 8,41 skin perfusion pressure 30,41 (also performed by Iida et al 10 ), tissue oxygen saturation mapping, 32 and the new group of molecular scintigraphic imaging techniques, 43,44 are available currently; these exams can provide valuable noninvasive microvascular (up to the molecular level) evaluation, 43,44 eventually by adding the angiosome orientation. 8,16,30,44 Interestingly, only a few publications regarding the importance of macro-and micro-circulation assessment in CLI are available in the literature 35 and even scarcer are observations about their specific investigation. 16,35 Although macrocirculatory arterial pathways generally respect the 6 foot and ankle angiosomes 1,2 (with 9%-12% described anatomical variations 37,46 ), independent microcirculatory evaluation (particularly in collateral-deprived patients) 8,[16][17][18]31,45 can be crucial while performing direct revascularization (Figs.…”

“…16,35,45 Since competent foot arches or large (.0.5 mm diameter) arterial-arterial connections are lacking, either real-time periprocedural microcirculatory analysis 30,32,35,41 or early postoperative capillary assessment may be beneficial. 16,35,42,44 In sum, it becomes clear that macro-and microcirculatory oxygenated flow 16,35 intentionally oriented toward specific ischemic foot wounds may enhance tissue healing. 9,20,21,35 Finally, however the direct revascularization concept is described in the literature, a correctly reconstituted blood supply remains crucial, whether it is carried by pre-designated angiosome bundles 2-9,15-21 or distributed by wound-oriented arterial axes in accordance with local competent arches or large arterialarterial foot perforators.…”

“…16,35,45 Since competent foot arches or large (>0.5 mm diameter) arterial-arterial connections are lacking, either real-time periprocedural microcirculatory analysis 30,32,35,41 or early postoperative capillary assessment may be beneficial. 16,35,42,44…”

Atherosclerosis Burdens in Diabetes Mellitus: Assessment by PET Imaging

“…Multiple publications have described the connection between diabetes and atherosclerosis [ 5 , 6 , 7 ] and the consequences of atherosclerosis in diabetic patients, including changes in cerebral [ 8 , 9 , 10 ] and cardiac perfusion and function [ 11 , 12 , 13 ], renal insufficiency [ 14 , 15 , 16 ], diabetic foot, etc. [ 17 , 18 , 19 ], topics that all deserve their own review.…”