COVID-19 Triggers Corneal Nerve Relapse After Groundbreaking Surgery
Innovative Procedure Fights Blindness, but Virus Poses New Threat
A woman who underwent a pioneering surgical procedure to restore sight in her right eye experienced a dramatic relapse after contracting COVID-19, underscoring the virus’s complex impact on nerve health. The case highlights the delicate balance of corneal nerve regeneration and the potential for viral infections to disrupt healing.
A Glimmer of Hope Dashed by Infection
In late 2021, a 59-year-old woman sought treatment for deteriorating vision in her right eye. Her sight had been compromised by a previous acoustic neuroma surgery, leading to facial paralysis and severe corneal damage classified as Mackie stage III neurotrophic keratopathy (NK). She had undergone multiple reconstructive procedures, including eyelid surgery and facial nerve transplantation.
Initial examinations revealed a significant lesion on her cornea, marked by epithelial erosion, stromal swelling, and new blood vessel growth. Her best-corrected visual acuity was a mere 0.01, and corneal sensation was virtually nonexistent. In vivo confocal microscopy (IVCM) confirmed a severe loss of subepithelial nerve fibers.
Pioneering Corneal Neurotization
To address the refractory NK, the patient was deemed a candidate for corneal neurotization, a procedure designed to restore nerve function to the cornea. The hospital, a leader in China for minimally invasive corneal neurotization (MICN), opted for this technique. MICN involves connecting healthy nerves to the damaged corneal nerves using nerve grafts.
The surgical approach utilized a sural nerve graft, harvested from the patient’s leg, to bridge the gap between the supraorbital and supratrochlear nerves and the cornea. This method was chosen over direct corneal neurotization (DCN) due to the patient’s history of cranial surgery, which could increase risks with DCN.
Recovery and Unexpected Setback
Following the MICN procedure and amniotic membrane transplantation, the patient showed promising signs of recovery. Within months, corneal clarity improved, and corneal sensation began to return. IVCM studies indicated a regeneration of nerve fibers.
However, thirteen months post-MICN, the patient contracted COVID-19. Within a week of symptom onset, her ocular condition worsened acutely. Examination revealed a new corneal lesion with inflammation and discharge. Despite initial treatment for suspected infectious keratitis, the ulcer progressed.
COVID-19 Linked to Corneal Deterioration
The diagnostic process revealed no identifiable pathogens through sequencing or cultures, and autoimmune markers were normal. Given the timing of the relapse with the SARS-CoV-2 infection and the characteristic clinical presentation, a diagnosis of COVID-19-related NK was made. This suggests the virus itself, or the body’s immune response to it, can trigger corneal nerve damage.
Corneal dendritic cell density, a marker of inflammation, significantly increased following the viral infection. Researchers noted that these cells can play a dual role: facilitating nerve repair after surgery but potentially exacerbating nerve injury during viral infections through immune-mediated mechanisms.
A Resilient Outcome
The patient’s management involved a multi-pronged approach, including antiviral medications, anti-inflammatory eye drops, nutritional support, and further amniotic membrane transplants. After a period of severe inflammation, the corneal ulcer eventually stabilized.
Twenty months after the COVID-19 infection, the patient reported significant alleviation of her symptoms. Her cornea had largely healed, with only a residual opacity. Crucially, her corneal sensation had improved to 30-40/60. This demonstrated that the neural pathways established through MICN could withstand and eventually recover from prolonged viral insult. The successful recovery in this case suggests that even after significant nerve damage and subsequent viral interference, the body’s capacity for neural repair remains.
