Corinthian Reference Lab (CRL), also known as The Nerve Lab, is a commercial diagnostic laboratory focused on neurological disease detection, with particular expertise in small fiber neuropathy. The laboratory specializes exclusively in epidermal nerve fiber density (ENFD) testing, which uses skin biopsy to provide objective evidence of neuropathy. This information can help physicians make a more accurate diagnosis and investigate potential underlying causes.

CRL supports medical practitioners with test-kit ordering and information about ENFD skin biopsy testing. Physicians can request test kits, while patients can use the website to make payments for their tests. The site also provides educational resources, frequently asked questions, a biopsy video, and highlighted research on small fiber neuropathy and the clinical use of skin biopsy.

CRL notes that small fiber neuropathy may have varied symptoms, including burning pain, tingling, pins and needles, numbness, or reduced pain sensitivity. Diabetes and glucose intolerance are among its common causes, though other conditions may also be involved.