Cryotherapy versus Laser Does Not Influence Anatomical Success following Vitrectomy for Primary Rhegmatogenous Retinal Detachment Repair: Registry Analysis of 2413 Patients

PURPOSE

To determine if a difference exists between cryotherapy and endolaser photocoagulation retinopexy in the rates of anatomical success following primary rhegmatogenous retinal detachment (RRD) repair with pars plana vitrectomy (PPV).

DESIGN

Registry-based, non-randomized, observational cohort study.

SUBJECTS

Eyes with primary RRD in a bi-national retinal surgery registry who underwent repair with PPV and had a minimum of 3-months follow-up.

METHODS

Cases were recorded prospectively by participating surgeons, and outcome was entered at 3 months. A generalized mixed model approach was used to compare the effect of retinopexy type on outcome. Variables known to be associated with retinal surgical success were considered as covariates for the final model. Eyes were divided into two groups: Cryo group (receiving cryotherapy as the only form of retinopexy) and Laser group (receiving endolaser as the only form of retinopexy).

MAIN OUTCOME MEASURES

The primary endpoint was the proportion of patients with stable retinal re-attachment without the need for further retinal detachment surgery, assessed 3-months post-operatively. Failure was defined as either retinal re-detachment, or foveal attachment with long-term silicone oil tamponade at endpoint. The secondary outcome measured was visual acuity at 3-months compared with baseline measurements.

RESULTS

Of a total 2413 patients included, the overall single-procedure success rate was 85%. There was no statistically significant difference in surgical success between the adjusted proportion of successful reattachment for the Cryo group (87%) when compared to the Laser group (82%) (p = 0.84, OR 1.04, 95% CI 0.74, 1.46). There was no difference between groups for the mean change in visual outcomes at 3-months (adjusted mean change of -0.48 logMAR for Cryo vs. -0.50 logMAR for Laser group, p=0.82).

CONCLUSIONS

Choice of cryotherapy versus endolaser retinopexy was not observed to influence the anatomical success of PPV for RRD, nor visual acuity outcomes at 3-months post-operatively.

The role of fingernail selenium in the association between arsenic, lead and mercury and child development in rural Vietnam: a cross-sectional analysis

As, Pb and Hg are common environmental contaminants in low- and middle-income countries. We investigated the association between child toxicant exposure and growth and development and determined if this association was mitigated by Se concentration. Toxicant concentrations in fingernail samples, anthropometry and Bayley's Scales of Infant Development, 3rd edition domains were assessed in 36-month-old children whose mothers had been part of a randomised controlled trial in rural Vietnam. Multivariable regression analyses were performed to estimate the effect of toxicant exposure on clinical outcomes with adjustments for potential confounders and interaction with fingernail Se concentration. We analysed 658 children who had data for at least one physical or developmental outcome, and at least one toxicant measurement, and each of the covariates. Fingernail As concentration was negatively associated with language (estimate per 10 % increase in As: -0·19, 95 % CI: (-0·32, -0·05)). Pb was negatively associated with cognition (estimate per 10 % increase in Pb: -0·08 (-0·15, -0·02)), language (estimate per 10 % increase in Pb: -0·18 (-0·28, -0·10)) and motor skills (estimate per 10 % increase in Pb: -0·12 (-0·24, 0·00)). Hg was negatively associated with cognition (estimate per 10 % increase in Hg: -0·48, (-0·72, -0·23)) and language (estimate per 10 % increase in Hg -0·51, (-0·88, -0·13)) when Se concentration was set at zero in the model. As Se concentration increased, the negative associations between Hg and both cognition and language scores were attenuated. There was no association between toxicant concentration and growth. As, Pb and Hg concentrations in fingernails of 3-year-old children were associated with lower child development scores. The negative association between Hg and neurological development was reduced in magnitude with increasing Se concentration. Se status should be considered when assessing heavy metal toxicants in children and their impact on neurodevelopmental outcomes.