Transillumination: A Diagnostic Tool to Assess Subungual Glomus Tumors

Abstract

Diagnosis of subungual glomus tumors is mainly based on clinical symptoms, including paroxysmal pain, tenderness, and cold intolerance. Dermoscopy, ultrasonography, and MRI constitute further diagnostic tools, commonly performed to demarcate the tumor before surgery. Herein, we present 2 cases of subungual glomus tumors, which could be diagnosed after fingertip transillumination, highlighting that this technique can serve as an easy, noninvasive, and cost-effective adjuvant diagnostic tool, to facilitate the clinical diagnosis of subungual glomus tumors as well as their localization during preoperative assessment.

Keywords: Dermoscopy; Glomus tumor; Nail surgery; Nail tumors; Transillumination.

Fig. 1

Case 1; 2 mm-wide, slightly bluish area within the lunula of the right thump (a) demarcation of the lesion after fingertip transillumination (b).

Fig. 2

Case 2; normal proximal nail fold and nail plate without ridging, onycholysis, or elevation (a), dermoscopy showing slightly bluish structureless area under the proximal medial nail plate (b), and demarcation of the lesion after fingertip transillumination (c).

Fig. 3

Case 2, MRI of the right middle finger demonstrating a well-demarcated, 7 mm-wide, subungual lesion; low-signal intensity on T1-weighted image (a), hyperintensity on T2-weighted image (b), and homogenous enhancement after injection of contrast material (c).