Specific PCR and Quantitative Real-Time PCR in Ocular Samples from Acute and Delayed-Onset Postoperative Endophthalmitis.

PURPOSE: Rapid identification of virulent pathogens is essential to strengthen the therapeutic strategy of acute endophthalmitis. OBJECTIVES: This study sought to compare the contribution of a combination of polymerase chain reaction (PCR)-based tests to culture methods, in patients with postoperative endophthalmitis. DESIGN: Prospective multicenter study diagnostic evaluation. METHODS: Setting: university referral centers. PARTICIPANTS: 153 consecutive patients presenting with acute or delayed-onset postoperative endophthalmitis, between 2008 and 2015. There were a total of 284 aqueous humor (AH) and/or vitreous fluid (VF) samples. Outcomes and measurements: microbiological tests of intraocular samples included bacterial culturing of pediatric blood culture bottles; 16SrDNA amplification and sequencing (panbacterial PCR) for detection and identification of all bacterial species; real-time PCR (qPCR) assays targeting the femA or lytA gene for detection of Staphylococcus aureus (S. aureus) or Streptococcus pneumoniae (S. pneumoniae), respectively; and a qPCR assay targeting the tuf gene for detection and quantification of Staphylococcus epidermidis (S. epidermidis). RESULTS: At the time of admission, the rate of detection of microorganisms by PCR-based tests was not significantly different than that by culturing (38% versus 30% in AH samples [n = 69]; 66% versus 63% in VF samples [n = 82], respectively). In contrast, after 1 intravitreal injection (IVI) of antibiotics, the identification rate by PCR-based tests was higher than that in VF by culturing (62% vs 48%, respectively; n = 94; P = 0.05). Bacteria were identified in 70% of patients, with a predominance of Gram-positive bacteria (93%). Specific qPCR tests targeting S. aureus and S. pneumoniae did not provide additional diagnoses but provided earlier results. The S. epidermidis load in vitreous at the time of patients' admission was higher in cases of final visual acuity (VA) of <20/40 (127,118 ± 125,848 DNA copies/mL) in patients with a VA of ≥20/40 (40350,000 ± 46,912 DNA copies/mL; P = 0.09). No significant changes in S. epidermidis load was found after one IVI. CONCLUSIONS: Patients with acute or delayed-onset endophthalmitis should benefit from microbiological identification in vitreous samples by combined analysis using bacterial cultures in pediatric blood culture bottles and panbacterial PCR. The last test was more effective than cultures in vitreous samples collected after an IVI of antibiotics. The qPCR tests targeting S. aureus and S. pneumoniae gave earlier results than culture and panbacterial PCR but did not provide additional diagnoses. As for S. epidermidis infections, determination of bacterial load using the qPCR test targeting the tuf gene could help evaluation of the visual prognosis of patients. Its role in the follow-up of patients after antibiotic treatment needs further investigation.

Relationship Between Nocturnal Intraocular Pressure Variations and Sleep Macrostructure.

PURPOSE: The purpose of this study was to characterize the relationships between nocturnal intraocular pressure (IOP) variations and sleep macrostructure in healthy subjects. METHODS: This was a cross-sectional study conducted in a center with shared expertise in chronobiology. Twelve healthy volunteers (22.3 ± 2.3 years) underwent a 24-hour IOP measurement session. The IOP variations of one eye were continuously estimated using a contact lens sensor (CLS) measuring the changes in corneal curvature related to the IOP and not requiring nocturnal awakening for measurements. The CLS measurement characteristics (mean, maximum, minimum, and amplitude) were evaluated across sleep stages (non-rapid eye movement [NREM] sleep [N1, N2, N3], REM) and assessed using polysomnography. The CLS signal measurement changes during sleep stage changes were calculated to evaluate the effects of sleep on IOP. RESULTS: A 24-hour IOP nyctohemeral rhythm was found in all subjects. During the nocturnal period, IOP signal values were significantly lower during wake stages than during REM and NREM N1, N2, and N3 sleep stages (P ≤ 0.04). The IOP signal values were significantly higher during the REM stage than during the NREM stages (P ≤ 0.03) and progressively decreased as NREM sleep deepened (P ≤ 0.04). We found a positive relationship between the micro-arousal index and the nocturnal period CLS signal SD (r = 0.76; P = 0.024) and a negative relationship between sleep efficiency and the nocturnal period CLS signal SD (r = -0.69; P = 0.041). CONCLUSIONS: Sleep micro- and macrostructure and nocturnal IOP variations are closely related in young subjects without sleep disorders. Across sleep stages, IOP is highest during REM sleep and progressively decreases as NREM sleep deepens.

Comparison of intraocular pressure measurements with the Reichert Pt100, the Keeler Pulsair Intellipuff portable noncontact tonometers, and Goldmann applanation tonometry.

PURPOSE: The aim of this study was to compare intraocular pressure (IOP) measurements using 2 portable tonometers, the Keeler Pulsair Intellipuff and the Reichert PT100, with Goldmann applanation tonometry (GAT). MATERIALS AND METHODS: Prospective cross-sectional study was conducted on normotensive and hypertensive patients recruited from the outpatient clinic of the University Hospital of Grenoble. IOP was measured using 2 portable noncontact tonometers (NCTs) and GAT in one eye of each patient in a random order. Central corneal thickness was measured with the Accutome PachPen Pachymeter. The Wilcoxon and t tests were used to compare the differences between tonometers, the Pearson and the Spearman correlation tests to evaluate the correlation among the methods, and the Bland-Altman plots to evaluate the agreement among the methods. Intraclass correlation coefficient (ICC) was used to evaluate the agreement among the methods in normotensive and hypertensive patients separately. RESULTS: A total of 137 eyes of 137 patients were included, 104 normotensive and 33 hypertensive eyes. We found an excellent agreement between PT100 and GAT (ICC=0.77) and between Intellipuff and GAT (ICC=0.75) in normotensive patients. We found a fair to good agreement (ICC=0.67) between PT100 and GAT in hypertensive patients. The agreement we found between Intellipuff and GAT was also excellent in hypertensive patients (ICC=0.86). Both NCTs significantly overestimated IOP measurements compared with GAT in normotensive and hypertensive eyes (mean of the differences between PT100 and GAT: 1.3±2.1 and 8.1±4.6 mm Hg in normotensive and in hypertensive patients, respectively (P<0.05), and between Pulsair Intellipuff and GAT: 1.5±1.8 and 2.3±4.8 mm Hg in normotensive and in hypertensive patients, respectively (P<0.05). CONCLUSIONS: The 2 NCTs agree well with GAT in normotensive patients. The Pulsair Intellipuff also agrees well with GAT in hypertensive patients.

Hourly awakening vs continuous contact lens sensor measurements of 24-hour intraocular pressure: effect on sleep macrostructure and intraocular pressure rhythm.

IMPORTANCE: All studies of 24-hour intraocular pressure (IOP) rhythm conducted to date have used repeated IOP measurements requiring nocturnal awakenings, potentially disturbing sleep macrostructure. OBJECTIVE: To evaluate the effects on sleep architecture and IOP rhythm of hourly awakening vs a contact lens sensor (CLS) to continuously monitor IOP without awakening. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional study at a referral center of chronobiology among 12 young healthy volunteers, with a mean (SD) age of 22.3 (2.3) years. INTERVENTIONS: Volunteers underwent two 24-hour IOP measurement sessions during a 2-month period. The eye order and session order were randomized. During one session, the IOP of the first eye was continuously monitored using a CLS, and the IOP of the fellow eye was measured hourly using a portable noncontact tonometer (session with nocturnal hourly awakening). During the other session, the IOP of the first eye was continuously monitored using a CLS, and the IOP of the fellow eye was not measured (session without nocturnal awakening). Overnight polysomnography was performed during the 2 sessions. MAIN OUTCOMES AND MEASURES: A nonlinear least squares, dual-harmonic regression analysis was used to model the 24-hour IOP rhythm from the CLS data. Comparisons of acrophase, bathyphase, amplitude, and the midline estimating statistic of rhythm were used to evaluate the effect of hourly awakening on IOP rhythm. To evaluate the effects of hourly awakening on sleep architecture, comparisons of sleep structure were used, including total sleep period, rapid eye movement, wake after sleep onset, absolute and relative total sleep time, and non-rapid eye movement sleep (N1, N2, and N3). RESULTS: A 24-hour IOP rhythm was found in all individuals for the sessions with and without awakening (P < .05). Hourly awakening for nocturnal IOP measurements increased wake after sleep onset (P = .04) but did not seem to change total sleep time, total sleep period, sleep efficiency, or slow-wave and rapid eye movement sleep stage duration (P > .30). Hourly awakening during noncontact tonometer IOP measurements did not seem to alter the mean variables of the 24-hour IOP pattern evaluated using CLS, including signal, maximum signal, minimum signal, acrophase, and bathyphase (P > .15). CONCLUSION AND RELEVANCE: The 24-hour IOP rhythms seem to be unaffected by hourly nocturnal awakening for IOP measurements in young healthy individuals.

Effect of overnight wear of the Triggerfish(®) sensor on corneal thickness measured by Visante(®) anterior segment optical coherence tomography.

PURPOSE: To evaluate the effect of overnight wear of the Triggerfish(®) contact lens sensor (CLS) on central corneal thickness (CCT) using the Visante(®) anterior segment optical coherence tomography (AS-OCT). METHODS: Twelve healthy subjects were studied in a sleep laboratory. An ophthalmic examination including ultrasonic CCT, corneal topography, specular microscopy and AS-OCT CCT was performed. Starting at 7 pm, the Triggerfish(®) CLS was fitted on one randomly selected eye. Similar AS-OCT measurements were taken on both eyes every 2 hr from 8 pm to 8 am. The CLS was removed just after the 8 am measurement session. Measurements were repeated at 9 am. RESULTS: Twenty-four eyes of 12 subjects were studied (mean age, 22.1 ± 2.4 years; four men/eight women). CCT significantly increased during the night in both CLS and control eyes (p < 0.01). The maximal change was +4.4 ± 1.7% in the CLS eyes and +2.9 ± 1.8% in the control eyes (p < 0.05). Throughout the night, CCT significantly increased more in eyes with CLS than in control eyes (p < 0.05). There were significantly more corneal curvature irregularities after overnight wear of the CLS than in the control eye: +1.63 Dioptre (D) versus -0.02 D in the 3-mm central zone and +3.17 D versus +0.01 D in the 5-mm central zone (p < 0.01). CONCLUSION: CCT and corneal curvature irregularities increased slightly but significantly more in eyes with the Triggerfish(®) CLS than in control eyes during overnight wear. Further studies are required to determine whether the corneal curvature changes modify the signal recorded by the sensor.

24-hour intraocular pressure rhythm in young healthy subjects evaluated with continuous monitoring using a contact lens sensor.

IMPORTANCE: This study evaluates a new device that has been proposed to continuously monitor intraocular pressure (IOP) over 24 hours. OBJECTIVE: To evaluate 24-hour IOP rhythm reproducibility during repeated continuous 24-hour IOP monitoring with noncontact tonometry (NCT) and a contact lens sensor (CLS) in healthy participants. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional study of 12 young healthy volunteers at a referral center of chronobiology. INTERVENTIONS: Participants were housed in a sleep laboratory and underwent four 24-hour sessions of IOP measurements over a 6-month period. After initial randomized attribution, the IOP of the first eye was continuously monitored using a CLS and the IOP of the fellow eye was measured hourly using NCT. Two sessions with NCT measurements in 1 eye and CLS measurements in the fellow eye, 1 session with CLS measurements in only 1 eye, and 1 session with NCT measurements in both eyes were performed. MAIN OUTCOMES AND MEASURES: A nonlinear least squares, dual-harmonic regression analysis was used to model the 24-hour IOP rhythm. Comparison of acrophase, bathyphase, amplitude, midline estimating statistic of rhythm, IOP values, IOP changes, and agreement were evaluated in the 3 tonometry methods. RESULTS: A significant nyctohemeral IOP rhythm was found in 31 of 36 sessions (86%) using NCT and in all sessions (100%) using CLS. Hourly awakening during NCT IOP measurements did not significantly change the mean phases of the 24-hour IOP pattern evaluated using CLS in the contralateral eye. Throughout the sessions, intraclass correlation coefficients of the CLS acrophase (0.6 [95% CI, 0.0 to 0.9]; P = .03), CLS bathyphase (0.7 [95% CI, 0.1 to 0.9]; P = .01), NCT amplitude (0.7 [95% CI, 0.1 to 0.9]; P = .01), and NCT midline estimating statistic of rhythm (0.9 [95% CI, 0.9 to 1.0]; P < .01) were significant. When performing NCT measurements in 1 eye and CLS measurements in the contralateral eye, the IOP change at each point normalized from the first measurement (9 am) was not symmetric individually or within the population. CONCLUSIONS AND RELEVANCE: The CLS is an accurate and reproducible method to characterize the nyctohemeral IOP rhythm in healthy participants but does not allow for estimating the IOP value in millimeters of mercury corresponding to the relative variation of the electrical signal measured.