Heidelberg Spectralis infrared video imaging: a clinical tool for diagnosing ocular torsional instability.

Heidelberg Spectralis infrared video imaging provides a diagnostic modality for the assessment of dynamic torsional instability of the eyes. It accurately detects monocular changes in both vertical and torsional eye position as fixation is switched from one eye to the other without the need for illuminating either eye. Heidelberg Spectralis infrared video imaging is useful for depicting the subtle torsional components of dissociated vertical divergence, latent nystagmus in patients with infantile esotropia.