Radiological Imaging of Nail Disorders (PART II) - Radiological Features of Nail Disease.

We have seen that radiological techniques like digital x-ray, high-frequency ultrasonography (USG), computed tomography (CT), and magnetic resonance imaging (MRI) have their unique roles in assessing a complex anatomical structure like the nail unit. Broadly speaking, USG and MRI help evaluate soft tissue components well; while, radiographs and CT scans help assess bony lesions better. In the second part of this review, salient radiological features of various nail disorders, as seen on these modalities are detailed. The radiological features mostly play a supportive role and help rule out differential diagnoses. However, in some diseases like retronychia and some nail tumors, radiological findings help clinch the diagnosis. The diagnostic features as well as the investigative modality of choice for a particular disease are highlighted based on the best level of evidence (LoE) available. This narrative review includes both infectious and non-infectious nail unit diseases, with special emphasis on nail unit tumors.