Granuloma annulare subtypes: sonographic features and clinicopathological correlation

Area of Science:

• Dermatology
• Medical Imaging
• Pathology

Background:

• Granuloma annulare (GA) diagnosis relies on clinical and histopathological findings.
• Limited data exists on the sonography of subcutaneous GA.
• Previous reports on GA sonography are sporadic.

Purpose of the Study:

• To evaluate the ultrasonographic patterns of localized, generalized, subcutaneous, and perforating granuloma annulare.
• To correlate sonographic findings with clinical and histopathological features of GA.

Main Methods:

• Retrospective observational study.
• Analysis of clinical, histopathological, and sonographic data from 15 GA patients.
• Correlation of imaging findings with disease variants.

Main Results:

• Identified three sonographic patterns: dermal (poorly defined hypoechoic band), hypodermal (irregular hypoechoic lumps), and mixed (ill-defined dermal/subcutaneous lesions).
• Observed increased blood flow signal on Doppler in five cases.
• Sonographic patterns varied across localized, generalized, subcutaneous, and perforating GA variants.

Conclusions:

• Sonographic features of localized, generalized, and perforating GA are reported for the first time.
• Findings align with previous reports on subcutaneous GA sonography.
• Ultrasonography can aid in characterizing different clinical variants of granuloma annulare.