The optimized evaluation of diabetic foot infection by dual isotope SPECT/CT imaging protocol.
Sequential Tc-99m hydroxymethylene-diphosphonate (HDP) 3-phase bone (BS) and In-111 leukocyte scanning (WBCS) have been frequently used to evaluate the diabetic foot, as nonosteomyelitis BS uptake is repeatedly observed and osteomyelitis (OM) in WBCS is often uncertain without BS correlation. Additionally, both modalities are limited in lesion localization because of low resolution and lack of anatomic details. We investigated a method that combined BS/WBCS, and if needed, WBCS/bone marrow scanning (BMS) using SPECT/CT to accurately diagnose/localize infection in a practical protocol. Blood flow/pool images were obtained followed by WBC reinjection and next day dual isotope (DI) BS/WBCS planar and SPECT/CT. BMS/WBCS SPECT/CT (step 2 DI) was obtained on the following day when images were suspicious for mid/hindfoot OM. Diagnosis accuracy and confidence were judged for the various imaging combinations. Diagnosis was classified as OM, soft tissue infection (STI), both OM/STI, and other/no bony pathology by microbiology/pathology or follow-up. Distinction between various diagnostic categories and overall OM diagnostic accuracy in 213 patients were higher for DI than WBCS or BS alone, and for DI SPECT/CT than DI planar or SPECT only. Diagnostic confidence/lesion site was significantly higher for DI SPECT/CT than other comparative imaging methods. In a group of 97 patients with confirmed microbiologic/pathologic diagnosis, similar results were attained. Step 2 DI SPECT/CT performed in 67 patients further improved diagnostic accuracy/confidence. DI SPECT/CT is a highly accurate modality that considerably improves detection and discrimination of STI and OM while providing precise anatomic localization in the diabetic foot. This combined imaging technique promises to beneficially impact diabetic patient care.
Heiba
Sherif I
SI
Nuclear Medicine Service, Nuclear Medicine Division, Mount Sinai School of Medicine, New York, NY 10029-6574, USA. Sherif.Heiba@mssm.edu
Kolker
Dov
D
Mocherla
Bharat
B
Kapoor
Karan
K
Jiang
Manli
M
Son
Hongju
H
Rangaswamy
Balasubramanya
B
Kostakoglu
Lale
L
Savitch
Ina
I
DaCosta
Maria
M
Machac
Josef
J
D017719:Diabetic Foot / Q000382:microbiology*; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007205:Indium Radioisotopes; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D010019:Osteomyelitis / Q000175:diagnosis*; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018461:Soft Tissue Infections / Q000175:diagnosis*; D013669:Technetium Tc 99m Medronate / Q000031:analogs & derivatives; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
D007205:Indium Radioisotopes; D019275:Radiopharmaceuticals; C024226:technetium Tc 99m hydroxymethylene diphosphonate; D013669:Technetium Tc 99m Medronate