Light-Near (Pupillary) Dissociation (LND)
Light-near pupillary dissociation refers to the loss of pupillary light reflexes, while the convergence-accommodation reaction is preserved (see Pupillary Reflexes). This dissociation may be seen in a variety of clinical circumstances:
- Argyll Robertson pupil: small irregular pupils with reduced reaction to light, typically seen in neurosyphilis; the absence of miosis and/or pupillary irregularity has been referred to as pseudo-Argyll Robertson pupil, which may occur with sarcoidosis, diabetes, and aberrant regeneration of the oculomotor (III) nerve
- Holmes-Adie pupil: dilated pupil showing strong but slow reaction to accommodation but minimal reaction to light (tonic > phasic)
- Parinaud’s syndrome (dorsal rostral midbrain syndrome): due to a lesion at the level of the posterior commissure, and character- ized by vertical gaze palsy, lid retraction (Collier’s sign) or ptosis, and large regular pupils responding to accommodation but not light.
Kawasaki A. Approach to the patient with abnormal pupils. In: Biller J (ed.). Practical neurology (2nd edition). Philadelphia: Lippincott Williams & Wilkins, 2002: 135-146