Characteristics of rhegmatogenous retinal detachment and their relationship to success rates of surgery.

PURPOSE: To determine features of rhegmatogenous retinal detachment predictive of anatomical success with surgical procedure. METHODS: All patients undergoing surgery at a tertiary referral practice had contemporaneous data collection in an electronic database. Overall, 847 eyes from 847 patients undergoing surgical procedure for rhegmatogenous retinal detachment were included in this study. RESULTS: Mean age was 62.2 years with 60% male subjects and 56% right eyes. Mean postoperative follow-up was 9.6 months (range, 6 weeks to 10 years). With univariate analysis, the presence of superotemporal breaks was associated with a reduction in the chance of failed primary surgery (P = 0.005); detached inferonasal breaks (P = 0.002), proliferative vitreoretinopathy (PVR) (P < 0.0001), breaks in detached inferior retina (P < 0.0001), fovea off (P = 0.001), and 4-quadrant rhegmatogenous retinal detachment (P < 0.0001) increased the risk of failure. After multivariate analysis PVR, detached inferior breaks, increased number of breaks, and 4-quadrant detachment remained associated with an increased risk of failure, and superotemporal detached breaks with the reduced risk of failure (r(2) = 0.08). For patients without PVR, only inferonasal detached breaks and 3 to 4 quadrants of detachment remained predictive of failure (r(2) = 0.04). For patients with PVR (n = 120), multivariate analysis showed that PVR C4-12 and posterior breaks increased the failure risk and detached superotemporal breaks reduced the risk of failure (r(2) = 0.22). CONCLUSION: Number of breaks, inferior positioning of breaks, the extent of rhegmatogenous retinal detachment, and PVR are associated with failed primary surgery.

A randomised controlled trial to compare patient satisfaction with two different types of local anaesthesia in ptosis surgery.

BACKGROUND: Ptosis surgery is performed under local anaesthetic to allow intra-operative assessment of lid positioning. Most commonly the anaesthetic is administered as a subcutaneous infiltration at the surgical site. Ptosis surgery using a regional nerve block has also been described, with reported advantages for minimising levator paralysis and disruption of the surgical landmarks. This study was designed to compare patient satisfaction with the two techniques of local anaesthetic administration. METHODS: 32 patients undergoing ptosis surgery were enrolled into a randomised controlled trial to receive local anaesthetic either by subcutaneous infiltration or by regional nerve block. Patient satisfaction was measured postoperatively with a self-administered vertical response column questionnaire, the Iowa Satisfaction with Anaesthesia Scale (ISAS). RESULTS: Of the 32 patients who were recruited 3 patients were excluded from analysis due to incomplete questionnaires or deviation from the trial protocol. Patient groups were well matched in terms of age, sex, time on waiting list, anaesthetic risk score, and operating grade of surgeon. Comparison of ISAS scores with the Mann Whitney test demonstrated an equal level of patient satisfaction with the two techniques. CONCLUSION: This randomised controlled trial found regional nerve blocks to be associated with equal levels of patient satisfaction as the more standard technique of diffuse infiltration of local anaesthetic along the upper eyelid. This result supports the use of regional nerve blocks as a valid alternative for anaesthesia in ptosis surgery.

Scheimpflug imaging to determine intraocular lens power in vivo.

PURPOSE: To assess the feasibility of determining intraocular lens (IOL) power by measurement of the central optic thickness using clinically available Scheimpflug imaging (Pentacam, Oculus). SETTING: King's College Hospital Ophthalmology Department, London, United Kingdom. METHODS: Sixty-seven eyes were assessed 1 month after uneventful phacoemulsification with in-the-bag implantation of AcrySof MA60AC IOLs (Alcon). The correlation between IOL thickness measurement and IOL power was calculated. Repeatability of central optic thickness measurement was determined from 10 successive scans of 4 patients. RESULTS: Within-subject standard deviation increased with the subject mean. The coefficient of variability was 1.4%. Measured lens thickness was highly correlated with lens power (R(2) = 0.94, P<.001). Over the measured range, 95% confidence intervals varied between +/-0.83 diopters (D) and +/-0.92 D. CONCLUSIONS: Central IOL thickness measurements with the Pentacam Scheimpflug camera were highly repeatable and closely correlated with the known IOL power. The IOL power, calculated from a regression equation, is likely to be less than +/-1.00 D away from the actual power. Approximate in vivo IOL power determination is feasible with clinically available Scheimpflug imaging. This could be applied clinically in cases of unexplained postoperative refractive error.