ABSTRACT
PURPOSE: To investigate the effect of prior anesthesia on the time to full cycloplegia in young Chinese subjects. METHODS: The amplitude of accommodation was monitored over a 50-minute interval after the application of 1% cyclopentolate hydrochloride with a pretreatment of 0.4% benoxinate (oxybuprocaine) or 0.9% saline solution (control). Using a nonlinear mathematical model, the rate of accommodative loss (k) and the time required for 95% of total cycloplegia (T95%) were determined. RESULTS: Statistical analysis revealed a significantly faster rate of accommodative loss (P < .0001) after prior anesthesia (0.129 +/- 0.05) compared with the controls (0.103 +/- 0.04). T95% was noted at 26.43 +/- 10.22 minutes after prior anesthesia, which was significantly shorter (P < .0001) than that after the saline treatment (35.28 +/- 16.51 minutes). CONCLUSIONS: Prior application of topical anesthetic can shorten the time to full cycloplegia for people, such as the Chinese, with dark irides.
Subject(s)
Accommodation, Ocular/drug effects , Anesthesia, Local , Cyclopentolate/administration & dosage , Muscarinic Antagonists/administration & dosage , Pupil/drug effects , Accommodation, Ocular/genetics , Adult , Anesthetics, Local/administration & dosage , Asian People , Eye Color/genetics , Humans , Ophthalmic Solutions , Procaine/administration & dosage , Procaine/analogs & derivatives , Time FactorsABSTRACT
The response of eye movements to edrophonium is easily missed by clinical observation alone. Binocular horizontal ten degree saccades were recorded by infrared oculography, whilst the vision of one eye was occluded, before and after fatigue repeated intravenous injection of dilute edrophonium, and fatigue induced during anticholinesterase inhibition by intravenous edrophonium, in 26 patients with diplopia or ptosis of uncertain aetiology. The most reliable criterion of a positive response was an increase in the amplitude of the saccades of the fixating eye by 10% or more after each of several injections of dilute edrophonium. The response was positive in 13 patients and was difficult to observe clinically when the responses of the saccades of the eyes moving conjugately were unequal and when the patient presented with ptosis and no diplopia. Edrophonium infrared oculography proved to be a sensitive test for weakness due to the neuromuscular junction defect of myasthenia gravis affecting extraocular muscles.
Subject(s)
Edrophonium , Myasthenia Gravis/diagnosis , Aged , Blepharoptosis/diagnosis , Diagnosis, Differential , Diplopia/diagnosis , Humans , Infrared Rays , Myasthenia Gravis/physiopathology , Oculomotor Muscles/physiopathology , SaccadesABSTRACT
Computed tomography detected an enlarged thymus in a 27-year-old man with myasthenia gravis of recent onset. Pathological examination of the thymus revealed lymphoid hyperplasia and a thymic seminoma (or germinoma), which was arising as an intramural nodule in a thymic cyst. This is the first reported association of thymic seminoma, lymphoid hyperplasia, and myasthenia gravis.
