# Persistent Unilateral Nerve Paresthesia Following Suspected Viral Infection

## TL;DR

A man developed long-lasting facial numbness after a suspected viral infection, suggesting a rare post-viral nerve condition.

## Contribution

This case report highlights post-viral infraorbital neuropathy as a rare but possible cause of facial paresthesia following respiratory infections like COVID-19.

## Key findings

- A 34-year-old male developed unilateral paresthesia after a suspected viral illness, with no structural or dental pathology identified.
- Diagnostic infraorbital nerve block confirmed the affected nerve region and temporarily relieved symptoms.
- The case supports post-viral neuropathy as a potential cause of facial paresthesia when other causes are ruled out.

## Abstract

The infraorbital nerve, a terminal branch of the maxillary division (V2) of the trigeminal nerve, supplies sensation to the upper lip, lower eyelid, and midface. Neuropathy in this distribution typically presents as paresthesia with or without anesthesia, dysesthesia, and/or allodynia. While trauma, dental pathology, sinusitis, and certain neurological conditions are possible causes, emerging literature has identified post‐viral neuropathies, including cranial mononeuropathies, as potential sequelae of COVID‐19. This case highlights a rare presentation of presumed post‐viral infraorbital neuropathy following an upper respiratory illness suspected to be COVID‐19. A 34‐year‐old male with controlled hypertension developed unilateral paresthesia of the upper left lip and infraorbital region following a presumed viral illness. Multidisciplinary evaluation included imaging (CT, panoramic, and intraoral radiographs), nasal endoscopy, bloodwork, and dental assessment. An infraorbital nerve block with bupivacaine was used diagnostically to confirm localization. No dental, neoplastic, or significant sinus pathology was identified. Symptoms persisted despite corticosteroids and antibiotics. Infraorbital nerve block reproduced symptoms of paresthesia and temporarily eliminated pain, confirming the affected nerve region. Given the timing postinfection and absence of structural causes, a working diagnosis of post‐viral infraorbital neuropathy was established. This case underscores the importance of including post‐viral neuropathy in the differential diagnosis of facial paresthesia, particularly following respiratory infections like COVID‐19. Diagnostic nerve blocks can aid both localization and symptom relief. As post‐viral neurological sequelae become more recognized, clinicians must consider cranial nerve involvement even in the absence of confirmatory testing or imaging abnormalities. A multidisciplinary approach remains essential for accurate diagnosis and effective management.