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?except as a side-effect of neuroleptic drugs. It consists of an uncomfortable forced upward or up- and-lateral tonic deviation of the eyes42. No Nystagmus or Dementia -- Nystagmus is not seen in idiopathic PD in contrast to postencephalitic PD, where it was common. Dementia is not found in young-onset PD patients. In elderly patients with PD, dementia is present far more often than in controls. Signs -- Meyerson's sign is the failure of the blink reflex to habituate to repeated glabellar tap. Wilson's sign is the need to blink in order to change saccadic direction. 3. MANAGEMENT Patients with PD typically complain of difficulty reading because of blurred vision, diplopia, photophobia, asthenopia, decreased vergences, ocular surface abnormalties33. In defining the complaint, take a careful history. Ask the patient about his activities at home and at work, how much time the patient spends reading, and the typical reading distance. Ask about computer time, since patients with PD often have difficulty with handwriting and may spend a lot of time at the computer. Ask the patient and caregiver about response to antiParkinson's medications. The effects of medications are often erratic and unpredictable. Parkinson's patients describe feeling like Alice in Wonderland, taking the “Eat me”- Sinemet but never knowing when they will be small enough to fit through a keyhole or big enough to fill the room. Ask how much time during a day is spent in the OFF-state, ON, and ON with dyskinesias. Ask whether the patient experiences more visual difficulty when OFF or when dyskinetic. Ask the patient where in the cycle of medication he considers his current state to fall. Eyeglasses should be made to correct in all eventualities. Take a careful medication history. Particularly note antidepressants and anticholinergics, which may contribute to hallucinations, dry eyes, etc. Make sure patient is adequately medicated with dopamine. Too much L-dopa leads to dyskinesias, making the patient appear less socially acceptable. But the patient may be more comfortable having dyskinesias than when rigid, akinetic, dependent, and in pain. PD patients should be managing their medications with the guidance of an enlightened movement disorder specialist, not the local internist. Do a careful refraction, providing the patient with a headrest to support the head during refraction. If the patient has difficulty sitting still at the phoropter, refract using a trial frame. In a patient experiencing dyskinesias and dystonias, bizarre head postures will interfere with astigmatic correction at near. Distance glasses are likely to fall off, get dropped and become bent and misaligned. Therefore, consider dispensing the spherical equivalent rather than a significant astigmatic correction for most patients. Dispense separate glasses for near, intermediate, and distance, not bifocals, even though this may necessitate 2 or 3 separate pairs of glasses. Patients with Parkinson’s have balance problems and those with a tendency to fall should not attempt to walk in bifocals. If the patient insists on bifocals resist Varilux since the patient's head control is too limited to find the right locus on the glasses most of the time. Provide a generous reading add in young PD patients. Under-correct myopia in young patients with PD so they can avoid the need for readers. Look for convergence and divergence insufficiency. Prescribe base-out prisms for distance and base-in prisms for near. If fusional amplitudes are too limited to permit single vision even with prismatic correction, comfortable single vision can be provided by translucent occlusion of one spectacle lens. Examine the eye movements. In the presence of severe supranuclear ophthalmoplegia, selective downgaze paresis, frequent squarewave jerks, axial rigidity, forward neck flexion, cerebellar signs, or prominent dysarthria, consider alternate diagnoses to idiopathic PD39. Blepharospasm is rare in idiopathic PD, and more common in PSP. Nevertheless, when it occurs it can be treated with BOTOX. Perhaps surprisingly, apraxia of eyelid opening also can improve with BOTOX. Before injecting BOTOX, aggressively treat external disease. Blepharitis has been traditionally treated with daily baby-shampoo lid scrubs in the shower; but for a slow-moving patient who needs help with balance in the shower, commercially available lid-scrub pads are easier to manage independently and yield better results. Non-preserved artificial tears should be recommended for frequent use throughout the day, but the patient may need help applying them if he has tremor. If Schirmer test shows low tear secretion, punctal occlusion can be considered. Many patients with low blink rates may enjoy resolution of visual blurring after a few good blinks. Avoid treating blepharitis with steroid preparations since they can precipitate glaucoma, which is difficult to diagnose and to follow in patients in whom performing visual fields and obtaining accurate intraocular pressure are problematic. Try to check the intraocular pressure by applanation tonometry, but use a tonopen if the patient has blepharospasm. Difficulties with reading can result from the patient losing his place through inability to hold his head still when he has dyskinesias. This can be ameliorated by using a finger as a placeholder. Slow reading due to paucity of eye movements also can be improved by using the finger to draw the eye across the page. Even with perfect refraction and clear vision, it is hard to read when the hand that is holding the book has a four cycle per second tremor of large amplitude. The patient should be encouraged to obtain a music stand or cookbook-holder so that the hand tremor will not interfere with his reading. One of the reasons patients with Parkinson's spend so much time on the Internet is that the computer screen sits still on the desk. Empathetic rehabilitation of the visual capacity of patients with PD may have an enormous positive impact on quality of life, not only for the patient but also for the family. These patients are usually intellectually alert but have lost control of motor functions that enable physical exploration, expression of personhood, and communication of ideas. Sight is therefore an especially critical “lifeline” for these patients. REFERENCES 1 Armstrong RA. 1997. Parkinson's Disease and the eye. Ophthal Physiol Optics 17 Suppl 2:S9- S16. 2 Barbata L, Rinalduzzi S, Laurenti M, Ruggieri S, Accornero N. 1994. Color visual evoked potentials in Parkinson's Disease. EEG Clin Neurophysiol 92:169-172. 3 Bennett KMB, Waterman C, Scarpa M, Castiello U. 1995. Covert visuospatial attentional mechanisms in Parkinson's disease. Brain 118:153-166. 4 Biousse V, Newman NJ, Carroll C, Mewes K, Vitek JL, Bakay RA, Baron MS, DeLong MR 1998.` Visual fields in patients with posterior GPi pallidotomy. Neurology 50:258-65. 5 Bodis-Wollner I, Tagliati M. 1988. The visual system in Parkinson's Disease. In Dopaminergic Mechanisms in Vision 390-394. 6 Bodis-Wollner I. 1990. Visual deficits related to dopamine deficiency in experimental animals and Parkinson's Disease patients. Trends Neurosci 13:296-302. 7 Bodis Wollner Marx M, Mitra M, Bobak P, Mylin L, Yahr M. 1987 Visual dysfunction in Parkinson's Disease. Brain 110:1675. 8 Bulens C, Meerwaldt JD, van der Wildt GJ, Keemink CJ. 1986. Contrast sensitivity in Paekinson's disease., Neurol 36:1121-1125. 9 Buttner T, Kuhn W, Muller T, Patzold T, Przuntek H. 1995. 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