Purpose: To audit and analyse the accuracy of current biometric formulae on refractive outcomes following cataract surgery in patients with axial length less than 22 mm. Methods: A total of 84 eyes from 84 patients with axial length <22 mm were identified from consecutive patients undergoing cataract surgery retrospectively at a single university hospital. All subjects had biometry using the IOLMaster (Carl Zeiss Meditec, Inc, Dublin, CA, USA) and a Sensar AR40 intraocular lens implant (Abbott Medical Optics, CA, USA). One eye from each patient was randomly selected for inclusion. Prediction errors were calculated by comparing expected refraction from optimized formulas (SRK/T, Hoffer Q, Haigis and Holladay 1) to postoperative refraction. A national survey of ophthalmologists was conducted to ascertain biometric formula preference for small eyes. Results: The mean axial length was 21.00 +/- 0.55 mm. Mean error was greatest for Hoffer Q at -0.57 dioptres. There was no significant difference in mean absolute error between formulae. SRK/T achieved the highest percentage of outcomes within 0.5 dioptres (45.2%) and 1 dioptre (76.2%) of target. Shallower anterior chamber depth was associated with higher mean absolute error for SRK/T (p = 0.028), Hoffer Q (p = 0.003) and Haigis (p = 0.016) but not Holladay (p = 0.111). Conclusion: SRK/T had the highest proportion of patients achieving refractive results close to predicted outcomes. However, there was a significant association between a shallower anterior chamber depth and higher mean absolute error for all formulae except Holladay 1. This suggests that anterior chamber depth with axial length should be considered when counselling patients about refractive outcome.

Editor, R etinal breaks have been treated by argon laser retinopexy for many decades (Gratton et al. 1984). Its use was first reported by Zweng (1972) in the 1960s and has since become established as the primary mode of treatment for retinal breaks. Prevention of progression to retinal detachment (RD) is the main objective and is dependent on numerous factors (Levin et al. 2009). Retinal breaks are difficult to treat if they are very anterior and if there is significant subretinal fluid or vitreous haemorrhage present. The benefit of laser retinopexy for symptomatic retinal breaks is well documented (Hyams et al. 1974; Smiddy et al. 1991; Blindbaek & Grauslund 2014), although little information exists regarding and risk of developing RD, despite this being the main objective. We performed a subgroup analysis of all patients recruited in the Scottish retinal detachment study at one centre. Patients who had received prior laser retinopexy were identified, and case notes were retrospectively analysed. We looked at location, size and number of breaks initially treated, the time interval between treatment and RD and whether further breaks were found at the time of RD. Further information such as laser parameters, visual acuity, refractive error, subretinal fluid, vitreous haemorrhage and other co-morbidities were also recorded. Additionally, all patients who had undergone laser retinopexy over the study period were identified from the laser record logbook given that a dated, contemporaneous entry, with patient details, is a mandatory requirement for every laser procedure. From this, we are able to estimate the RD rate following laser retinopexy for retinal breaks. The Scottish retinal detachment study was a prospective populationbased epidemiology study (Mitry et al. 2009). Between 1 November 2007 and 31 October 2009, a comprehensive system was established in which each patient with primary RRD in UK was approached for study inclusion. Criteria for inclusion into this study were patients recruited into the Scottish retinal detachment study at one centre who had received previous laser retinopexy. Nine patients were identified as suitable for inclusion into the study, six male three female with a mean age of 53.7 years. A distinct feature enables these patients to be divided into two groups. Five developed RD within 100 days of the initial retinopexy (early RD); the remaining four developed RD between 747 and 1739 days (late RD). Over this time period, 158 patients underwent laser retinopexy. Five of these patients (early RD group) developed a RD giving a RD rate of 3.16% within 3 years. Four patients had multiple breaks at presentation requiring retinopexy (three early RD, onr late RD); six had significant subretinal fluid of >1 clock hour (four early RD, two late RD). Five patients had vitreous haemorrhage (four early RD, one late RD) at the time of initial retinopexy. All early RDs had new breaks identified at the time of RD, whereas in the late RD group, two patients had new breaks and two had progression from the same break. Laser retinopexy is a safe and effective treatment for symptomatic retinal breaks. Our patients can be divided into early RD and late RD groups, as the two seem to have different characteristics. In our series, early detachments occurred from new or missed breaks. This emphasizes the importance of complete peripheral retinal examination to ensure that breaks are not missed as even those with multiple breaks did not detach early from the treated breaks. Of the patients in the late RD group, two detached from the same treated retinal break. This may be due to initial undertreatment with slow progression, or from minor innocuous ocular trauma, which may progress to RD through areas of weak retinal adhesion. The primary objective when performing a laser retinopexy is to prevent RD. The failure rate of primary laser retinopexy has not been previously reported. Our study provides information regarding the rate of RD following laser retinopexy which may be of benefit when consenting patients to the procedure. Importantly, patients must be informed that despite seemingly adequate initial treatment, some patients still develop RD from new breaks and this may occur after a significant period of time has passed.

Objective: Argon laser retinopexy has been the primary treatment for retinal breaks for many decades. Prevention of progression to retinal detachment (RD) is the main objective. The benefit of laser retinopexy is well documented, although little has been reported on the risk factors for progression to RD. By addressing this issue, patients at high risk can be identified, and more timely specialist retinal input can be sought.Methods: Data over a 6-month period from 45 consecutive patients undergoing laser retinopexy were reviewed. Patients were categorized into complete success (no more than 1 laser treatment), qualified success (no more than 3 laser or cryotherapy treatments), and treatment failure (more than 3 laser or cryotherapy treatments or progression to RD).Results: Complete success was observed in 53.5% of patients, a further 34.9% of patients achieved a qualified success, and the remainder of the patients (11.6%) fell into the treatment failure category. About 9.3% of patients required cryotherapy, and 7.0% of patients underwent RD surgery. Patients with a bridging blood vessel and vitreous hemorrhage were significantly more likely to be in the treatment failure category than those without. RD was significantly associated with the presence of vitreous hemorrhage.Conclusions: Patients with retinal breaks associated with bridging blood vessels and vitreous hemorrhage are at greater risk for poorer outcome. The area of subretinal fluid was not linked to failure. It complete laser of a tear is not possible or it concerns remain regarding treatment efficacy, prompt referral to a retina specialist for further management is recommended.

PURPOSE:The purpose of this study was to describe a patient with an untreated rhegmatogenous retinal detachment, first diagnosed during pregnancy, that underwent spontaneous resolution after normal labor and childbirth.METHODS:Descriptive case report.RESULTS AND DISCUSSION:It has been extensively documented that normal labor and childbirth are safe in the context of rhegmatogenous retinal detachment. Although exudative retinal detachment is a well-known complication of preeclampsia, spontaneous reattachment of a rhegmatogenous retinal detachment is a rare phenomenon. In this case, labor-induced physiologic changes may have contributed to the resolution of the detachment.

AIM:Diabetic patients are at significant risk of developing corneal lesions such as superficial punctate keratitis, recurrent corneal erosions, persistent epithelial defects, and microbial keratitis. The aim of this study was to investigate whether diabetes mellitus is correlated with both reduced corneal sensation and reduced tear production. METHODS:In 25 type II diabetic patients with a history of retinopathy only and in 25 nondiabetic control subjects (age and sex matched), we performed noncontact corneal aesthesiometry and assessed basal tear production using Schirmer's test with topical anesthesia. The noncontact corneal aesthesiometer (NCCA) is a new noninvasive device for quantifying threshold corneal sensitivity. RESULTS:The diabetic patients demonstrated a significantly reduced Schirmer's test result (P<.001) and significantly reduced corneal sensitivity (P<.01). CONCLUSION:Our study supports previous reports of reduced basal tear production, lending more support to the theory of a peripheral neuropathy affecting lacrimal gland function in diabetes. We also confirmed reduced threshold corneal sensitivity in diabetic patients using the NCCA.

sharp edge of the probe cutting conjunctival vessels and causing bleeding.Thin adherent debris was then carbonized, allowing the laser tip temperature to rise and causing scleral perforation.The defect required suturing.This led to the redesigning of the laser probe tip.In our case, there was no such carbonized debris seen and we think it is unlikely to be the reason for our perforation.Sabri and Vernon 10 reported a case of scleral perforation using the new contact G-probe.The defect required suturing with two 10-0 vicryl sutures.However, 1 week later, the scleral leak recurred and further suturing was needed.In our case, with crepe bandage and oral acetazolamide for 1 day, we were able to stop the leakage.During subsequent follow-up, the scleral hole healed and was covered by intact conjunctival epithelium.This demonstrated that suturing may not always be necessary, especially when the perforation is small.Pre-existing scleral thinning is a common risk factor in the two previously reported cases, and also in our patient.Hence, Sabri and Vernon 10 suggested the use of a lower laser power setting (50%), though there is no good proof that such a lower power could prevent perforation and is still as effective.With heightened awareness of this complication, and appropriate management when it occurs, we believe the risk of scleral perforation and its consequences could be minimized.