Diagnosis of onychomycosis using the periodic acid–Schiff (PAS) test for sensitive identification of hyphae and fungal culture for identification of species has become the mainstay for many clinical practices. With the advent of polymerase chain reaction (PCR) testing, physicians can identify a fungal toenail infection quickly with the added benefit of species identification. We compared PAS testing with multiplex PCR testing from a clinical perspective.
A total of 209 patients with clinically diagnosed onychomycosis were recruited. A high-resolution picture was taken of the affected hallux nail, and the nail was graded using the Onychomycosis Severity Index. A proximal sample of the affected toenail and subungual debris were obtained and split into two equal samples. One sample was sent for multiplex PCR testing and the other for PAS testing. The results were analyzed and compared.
Six patients were excluded due to insufficient sample size for PCR testing. Of the remaining 203 patients, 109 (53.7%) tested positive with PAS, 77 (37.9%) tested positive with PCR. Forty-one patients tested positive with PAS but negative with PCR, and nine tested positive with PCR but negative with PAS.
Physicians should continue the practice of using PAS biopsy staining for confirmation of a fungal toenail infection before using oral antifungal therapy. Because multiplex PCR allows species identification, some physicians may elect to perform both tests.
Hallux abducto valgus is a triplane deformity with recent attention given to the significance of correcting the coronal plane component. This study explored the accuracy of the forefoot axial (FFA) study as a standard radiographic assessment method compared with weightbearing computed tomography (CT).
Twelve feet with hallux abducto valgus from 12 individuals were included in this study. Three images of the affected foot were taken: FFA radiograph and weightbearing CT with the foot in maximum pronation (pronated CT) and maximum supination (supinated CT). Five investigators determined the sesamoid rotation angles (SRAs) from each of the images. The measurements from a single investigator were used to compare the SRA means from each of the image types, and those from all five investigators were used to determine reliability.
The mean ± SD SRA was 22.1° ± 7.6° for pronated CT, 10.5° ± 5.0° for supinated CT, and 12.2° ± 9.4° for FFA images. The mean SRA from the pronated CT was significantly greater than the supinated CT (P < .001) and FFA (P < .005) SRAs. There were no significant differences in mean SRA between the FFA and supinated CT images (P > .99). Results indicated high reliability in measurements among investigators.
Using weightbearing CT, these findings indicate that the sesamoids significantly alter their position in the coronal plane, as determined by the SRA, with changes in weightbearing subtalar joint position. Moreover, the affected foot positioning required for determining the SRA from the FFA radiograph seems to significantly underestimate the true SRA. Thus, use of this image in surgical hallux abducto valgus planning is called into question.
We developed a prototype of a novel thermochromic liquid crystal (TLC)–coated fabric with an extended temperature range and enhanced sensitivity. By incorporating color and pattern recognition into the fabric, rapid determination of the underlying pedal temperature is facilitated. The purpose of this study was to evaluate the accuracy of the TLC fabric as a potential diagnostic aid for identifying complications in the high-risk foot.
The hands of 100 individuals were used to compare the mean maximum temperatures indicated by the fabric versus standard thermal camera images. Findings were statistically analyzed using a paired t test, with significance defined as P < .05.
Except for the tip of the thumb and regions in the palm, there were no statistically significant differences between mean maximum temperatures measured with the thermal camera and those detected with the TLC fabric. Minor differences were relatively consistent in all nine regions of the hand and were not considered to be clinically significant.
Using direct visual analysis, we demonstrated that a novel TLC fabric could accurately map temperatures in the palmar surface of the hand. The findings support the continued development of a temperature-sensitive sock that can be used in the home to monitor for temperature changes that may indicate the onset of complications in the high-risk foot.