Ultrasound biomicroscopy in the diagnosis of skin diseases.

Abstract

Ultrasound scanning is becoming an important diagnostic tool in dermatology. The major advantages of this technique are its non invasive non-ionizing nature and its relatively low cost. We aimed to evaluate the accuracy of ultrasound biomicroscopy (UBM) in the diagnosis of eight skin disorders namely, morphea, keloid, lichen planus, chronic eczema, psoriasis, port wine stain, seborrheic keratosis, and photo-aged skin, through correlation of its findings with clinical and pathological assessment. Fifty seven patients with the above diseases were examined by ultrasound biomicroscopy (UBM). Two areas, one of normal skin and the other from lesional skin, were examined for each patient. Skin biopsies were taken from the same lesion examined by UBM. In morphea, the dermal echogenicity was increased and the thickness of morphea plaques correlated significantly with disease severity. Keloids appeared as low echogenic images. In lichen planus and chronic eczema the dermis appeared as sound shadow. In psoriasis, an intermediate zone between the epidermis and dermis (B zone) was detected. Its thickness correlated significantly with the PASI score. Port wine stain lesions appeared hypoechoic. Seborrheic keratosis appeared as a sound shadow. In photo-aged skin a subepidermal low echogenic band (SLEB) was detected. We conclude that UBM is a non-invasive diagnostic tool in dermatology which can be used to give valuable information about disease progress and the effectiveness of therapy.