99mTc-methoxy-isobutyl-isonitrile Scintigraphy Demonstrates Enhanced Foot Perfusion Following Dellon Decompression in Patients With Diabetic Neuropathy

Background: Diabetic neuropathy, a prevalent complication of diabetes mellitus, is frequently associated with peripheral vascular insufficiency and diabetic foot ulcers (DFUs). Dellon decompression of the tarsal tunnel has demonstrated efficacy in restoring sensory function and improving microcirculation in affected limbs. This prospective study aimed to evaluate changes in foot perfusion following Dellon tarsal tunnel decompression using both 99m Tc-methoxy-isobutyl-isonitrile ( 99m Tc-MIBI) scintigraphy and Doppler ultrasonography. Methods: Ten patients with diabetes with chronic DFUs (mean duration, 17.1 mo) underwent Dellon tarsal tunnel decompression. Sensory nerve function was assessed via 2-point discrimination (TPD) testing at baseline and 12 months postoperatively. Perfusion was quantified at 12-month follow-up using Doppler ultrasonography to measure peak systolic velocity in the posterior tibial artery and 99m Tc-MIBI scintigraphy to compare perfusion in the operative versus contralateral foot. Results: Postoperative evaluation showed significant improvement in sensory function (TPD, P < 0.001) and posterior tibial artery flow (mean velocity increased from 43.2 to 79.4 cm/s, P < 0.0001). Scintigraphy revealed increased uptake in the operative foot during both early (16–150 versus 8–80 counts) and delayed phases (33–290 versus 15–165 counts), along with shorter time-to-peak activity and a mean uptake increase of 38.5% (rest) and 36.8% (stress). All DFUs healed by the 12-month follow-up. Conclusions: Dellon decompression significantly enhances sensory function and microvascular perfusion in patients with diabetes. Improved perfusion, confirmed by both 99m Tc-MIBI scintigraphy and Doppler ultrasonography, suggests a potential role for local sympathectomy in promoting DFU healing.