Objective: To describe the characteristics of spontaneous recovery of homonymous hemianopia (HH).
Methods: The authors reviewed medical records of all patients with HH confirmed by formal visual field testing and seen in follow-up in their service between 1989 and 2004. Clinical characteristics, causes, neuroradiologic definition of lesion location, final outcome, and evolution of the visual field defects were recorded. The associations among final visual field defect outcome, time from injury, and clinical features were analyzed.
Results: A total of 254 patients with 263 HH were included in this study. Spontaneous visual field defect recovery was observed in 101 HH (38.4%). The likelihood of spontaneous recovery decreased with increasing time from injury to initial visual field testing (p = 0.0003). The probability of improvement was related to the time since injury (p = 0.0003) with a 50 to 60% chance of improvement for cases tested within 1 month after injury that decreased to about 20% for cases tested at 6 months after surgery. No other factor was found to correlate with the final outcome of the visual field defects. Improvement after 6 months from injury was mild and usually related to improvement of the underlying disease.
Conclusion: Spontaneous improvement of homonymous hemianopia is seen in at least 50% of patients first seen within 1 month of injury. In most cases, the improvement occurs within the first 3 months from injury. Spontaneous improvement after 6 months postinjury should be interpreted with caution as it is most likely related to improvement of the underlying disease or to improvement in the patient's ability to perform visual field testing reliably.