Evaluation of surgical performance with intracameral mydriatics in phacoemulsification surgery.

PURPOSE: To evaluate surgical performance using intracameral mydriatics (ICM) in phacoemulsification surgery in a series of consecutive cases. METHODS: In a series of 198 consecutive procedures 50-200 microl of cyclopentolate 0.1%, phenylephrine 1.5% and lidocaine 1% was given intracamerally for mydriasis and anaesthesia. The previous 198 cases, dilated with topical mydriatics, were studied for comparison. Several pre- intra- and postoperative parameters were registered, and the subjective surgical performance was graded after each procedure. In 41 consecutive cases, the change in pulse and oxygen saturation induced by the ICM injection was registered. RESULTS: No increase in operation time or complication rates was seen with ICM, compared to when standard topical mydriatics were used. The subjective surgical performance was ranked as equally good for both groups. CONCLUSION: From this clinical evaluation, our impression is that ICM performs well in routine phacoemulsification surgery.

Posthypnotic suggestion and the modulation of Stroop interference under cycloplegia.

Recent data indicate that under a specific posthypnotic suggestion to circumvent reading, highly suggestible subjects successfully eliminated the Stroop interference effect. The present study examined whether an optical explanation (e.g., visual blurring or looking away) could account for this finding. Using cyclopentolate hydrochloride eye drops to pharmacologically prevent visual accommodation in all subjects, behavioral Stroop data were collected from six highly hypnotizables and six less suggestibles using an optical setup that guaranteed either sharply focused or blurred vision. The highly suggestibles performed the Stroop task when naturally vigilant, under posthypnotic suggestion not to read, and while visually blurred; the less suggestibles ran naturally vigilant, while looking away, and while visually blurred. Although visual accommodation was precluded for all subjects, posthypnotic suggestion effectively eliminated Stroop interference and was comparable to looking away in controls. These data strengthen the view that Stroop interference is neither robust nor inevitable and support the hypothesis that posthypnotic suggestion may exert a top-down influence on neural processing.

Prior topical anesthesia reduces time to full cycloplegia in Chinese.

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.

[Intracameral lidocaine and phacoemulsification under topical anesthesia. Apropos of 80 operations]. / Lidocaïne intracamérulaire et phacoémulsification sous anesthésie topique. A propos de 80 interventions.

PURPOSE: To evaluate the advantage of intracameral unpreserved lidocaine for patient comfort during phacoemulsification under topical anesthesia. METHODS: In this prospective study, we performed 80 phacoemulsifications under topical anesthesia, with tetracaine 1% drops, 10 minutes before and at the start of surgery: 40 patients received 0.3 cc balanced salt solution (BSS) intracameral injection; 40 patients received 0.3 cc unpreserved lidocaine 1% intracameral injection. The same surgical procedure was performed in both groups: 3.2 mm temporal corneal self-sealing incision, capsulorhexis, foldable polyHEMA IOL implantation into the capsular bag. There was no intravenous sedation. RESULTS: Forty-eight percent (19) in the BSS group and 70% (28) in the lidocaine group felt no pain. 10% (4) in the BSS group reported sharp pain during phacoemulsification. During IOL insertion, no pain was reported by 48% (19) in the BSS group, and 75% (30) in the lidocaine group; 10% (4) in the BSS group felt severe pain (significant difference: p < 0.05). Endothelial cell loss was 6% in the BSS group, and 6.4% in the lidocaine group (non significant difference). CONCLUSION: Intracameral lidocaine is safe and effective in decreasing discomfort among patients undergoing phacoemulsification under topical anesthesia.

Presumed ophthalmic herpes zoster after contralateral cataract extraction.

Herpes zoster ophthalmicus (HZO) may occur spontaneously, but can be precipitated by stress, trauma, debility or systemic illness. A case is here reported of Herpes zoster involving the contralateral eye, associated with a midline skin rash, following cataract extraction under local anaesthesia.

Plasma concentrations and ocular effects of cyclopentolate after ocular application of three formulations.

1. Eight volunteers received in randomized order two 30 microliters drops of either 1% w/v cyclopentolate hydrochloride or a corresponding amount of cyclopentolate polygalacturonate in saline or in acetate buffer in one eye. Cyclopentolate concentrations in plasma were measured by a radioreceptor assay. 2. Peak plasma drug concentrations of about 3 ng ml-1 occurred within 30 min after all formulations. Occasionally, a second concentration peak in plasma, probably reflecting drug absorption from the gastrointestinal tract, was seen after 2 h. The mean elimination half-life of cyclopentolate was 111 min when all subjects and formulations were considered together. There were no statistically significant differences between the formulations with respect to the time-course of plasma drug concentration. 3. The maximal mydriatic effect was reached within about 15 min and was maintained for several hours, often being 1/3 of its peak value after 30 h. Similarly, an intense cycloplegic response was achieved within a few minutes, the peak changes in the near-point of vision being 9 to 10 dioptres. The cycloplegic response was more intense after one of the polygalacturonate complexes, especially at later time points.