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BackgroundIdentification of bacterial pathogens in endophthalmitis is important to inform antibiotic selection and treatment decisions. Hemoculture bottles and polymerase chain reaction (PCR) analysis have been proposed to offer good detection sensitivity. This study compared the sensitivity and accuracy of a blood culture system, a PCR approach, and conventional culture methods for identification of causative bacteria in cases of acute endophthalmitis.MethodsTwenty-nine patients with a diagnosis of presumed acute bacterial endophthalmitis who underwent vitreous specimen collection at King Chulalongkorn Memorial Hospital were enrolled in this study. Forty-one specimens were collected. Each specimen was divided into three parts, and each part was analyzed using one of three microbial identification techniques: conventional plate culture, blood culture, and polymerase chain reaction and sequencing. The results of the three methods were then compared.ResultsBacteria were identified in 15 of the 41 specimens (36.5%). Five (12.2%) specimens were positive by conventional culture methods, 11 (26.8%) were positive by hemoculture, and 11 (26.8%) were positive by PCR. Cohen’s kappa analysis revealed p-values for conventional methods vs. hemoculture, conventional methods vs. PCR, and hemoculture vs. PCR of 0.057, 0.33, and 0.009, respectively. Higher detection rates of Enterococcus faecalis were observed for hemoculture and PCR than for conventional methods.ConclusionsBlood culture bottles and PCR detection may facilitate bacterial identification in cases of presumed acute endophthalmitis. These techniques should be used in addition to conventional plate culture methods because they provide a greater degree of sensitivity than conventional plate culture alone for the detection of specific microorganisms such as E. faecalis. Trial registrationThai Clinical Trial Register No. TCTR20110000024.

PurposeWe compared the accuracy of axial length (AL) measurement obtained by optical biometry with that obtained by acoustic biometry in eyes with rhegmatogenous retinal detachment (RRD).Patients and methodsThis prospective descriptive analytic study measured the AL of eyes with RRD preoperatively and 3 months postoperatively using optical biometry (intraocular lens [IOL] master group) and acoustic biometry (immersion A-scan group). Preoperative and postoperative measurements were compared by paired t-test. The agreement between preoperative and postoperative measurements was analyzed using a Bland–Altman plot. Subgroup analysis of macular involvement status was performed.ResultsTwenty-seven eyes were analyzed in this study. The mean AL in the IOL master group was 23.58±0.97 mm preoperatively and 24.17±1.16 mm postoperatively; the mean difference was −0.59±0.90 mm (P = 0.007). The mean AL in the immersion A-scan group was 24.29±1.59 mm preoperatively and 24.27±1.69 mm postoperatively; the mean difference was 0.02±0.48 mm (P = 0.827). Bland–Altman analysis revealed disagreement between preoperative and postoperative AL measurements in both techniques. In subgroup analysis of macula with RRD, there were significant differences between preoperative and postoperative AL measurements in the IOL master group (P = 0.014).ConclusionSignificant underestimation of AL measurement was observed when using the IOL master in eyes with RRD with macular involvement, which could affect IOL power selection.