Corneal cross-linking for treatment of keratoconus relapse in post-keratoplasty eyes.

PURPOSE: Keratoconus relapse after penetrating keratoplasty is a rare condition that may result in severe visual deterioration and corneal graft thinning. Therefore, treatment to stabilize the cornea should be considered. The purpose of this study was to evaluate the safety and efficacy of Corneal Cross-Linking (CXL) in eyes with relapse of keratoconus after penetrating keratoplasty for keratoconus. MATERIALS AND METHODS: A retrospective review of eyes that developed keratoconus relapse following a penetrating keratoplasty and treated with CXL. The main outcome measures were change in maximal keratometry (Kmax), best-corrected distance visual acuity (BCVA), thinnest corneal thickness (TCT) and central corneal thickness (CCT), and complications. RESULTS: We identified 10 consecutive eyes of 9 patients. Preoperative median BCVA before the CXL and 1 year after the CXL procedure remained stable (p = 0.68). The median (IQR) of Kmax improved from 63.2 (24.9) D before the CXL procedure to 62.2 (27.1) D at 1 year postoperatively (P = 0.028). Median TCT and CCT also remained with no significant change 1 year after CXL. No complications were noted following the procedure. CONCLUSION: CXL in eyes with keratoconus relapse after keratoplasty is a safe and effective procedure enabling not only visual stabilization but also might bring keratometry improvement. Routine follow-up after keratoplasty should be performed for early detection of keratoconus relapse and CXL is timely advised when such a relapse is documented.

Radiation dose reduction for chest radiography of infants in intensive care units using a high peak kilovoltage-technique.

BACKGROUND: Chest radiography is an important tool in the care of infants in intensive care units. Image optimization must be monitored to minimize radiation exposure in this susceptible population. OBJECTIVE: To examine the use of a high tube peak kilovoltage technique to achieve radiation dose reduction while maintaining adequate image quality. MATERIALS AND METHODS: A retrospective study was conducted. Radiation doses of chest radiographs performed in the pediatric intensive care units in our institution were calculated. The radiographs were divided into two groups based on the value of the peak kilovoltage used: above and below 60 kilovolts (kV). Image quality was blindly assessed by two fellowship-trained pediatric radiologists. Air kerma, effective dose and quality score for the high versus the low peak kilovoltage group were compared and analyzed. RESULTS: The study included 376 radiographs. One hundred and seven radiographs were performed using peak kilovoltage values equal to or above 60 kV and 269 radiographs were performed using values under 60 kV. The average air kerma for the lower peak kilovoltage group was 56.6 microgray (µGy) (30.7-81.9) vs. 22.9 µGy (11.8-34.4) for the higher peak kilovoltage group (P<0.0001). The mean difference in effective dose between the groups was 11.68 (P<0.0001). The mean difference for the quality score was 0.06 (±0.03, P=0.10), not statistically significant. CONCLUSION: A high peak kilovoltage technique may enable a statistically significant radiation dose reduction without compromising the diagnostic value of the image.

Thicker macula in asymptomatic APOE Ɛ4 middle-aged adults at high AD risk.

INTRODUCTION: We compared retinal layers' thickness between apolipoprotein E (APOE) Ɛ4 carriers and non-carriers in a cohort of cognitively normal middle-aged adults enriched for Alzheimer's disease (AD) risk. METHODS: Participants (N = 245) underwent spectral domain optical coherence tomography. Multivariate analyses of covariance adjusting for age, sex, education, and best corrected vision acuity was used to compare retinal thickness between APOE groups. RESULTS: Participants' mean age was 59.60 (standard deviation = 6.42) with 66.4% women and 32.2% APOE Ɛ4 carriers. Greater macular full thickness was observed in APOE Ɛ4 carriers compared to non-carriers (P = .017), reaching statistical significance for the inner and outer nasal (P = .009 and P = .005, respectively), inner superior (P = .041), and inner and outer inferior (P = .013 and P = .033, respectively) sectors. The differences between APOE groups were mainly driven by the ganglion cell layer (P < .05) and the inner plexiform layer (P < .05). DISCUSSION: A thicker macula is observed already in midlife asymptomatic APOE Ɛ4 carriers at high AD risk.

COVID-19's Influence on Ocular Emergency Visits at a Tertiary Referral Center and Its Relationship to Emergency Indications by the American Academy of Ophthalmology.

PURPOSE: To examine the trends of ocular emergency admissions during the COVID-19 pandemic at a tertiary care center. METHODS: The study's sample consisted of all patients who were seen in the ophthalmic emergency room (OER) between March 15 and April 15, 2020 (during the COVID-19 pandemic) and in the same time frame of the previous year. The cases were categorized as urgent vs. nonurgent according to the AAO urgency guidelines during the coronavirus period, and the ability to treat the case with telemedicine was evaluated retrospectively. RESULTS: A total of 553 patients were admitted to the OER during the pandemic period, whereas in the same time frame of the previous year, 1,069 were admitted. The female/male proportion was 526/543 (49.2%/50.8%) in 2019 and 258/259 (46.7%/53.3%) the following year. Age (years, average ± SD) was 44.7 ± 24.5 in 2019 and 47.9 ± 23.4 in 2020. There were more self-referrals in 2020 compared to 2019 (41.1% vs. 32.6%; p=0.0004). The time spent in the OER was reduced from 109 ± 74 (minutes, average ± SDV) in 2019 to 73 ± 51 in 2020 (p < 0.0001). The most common cause of OER examinations in 2020 was related to the posterior segment of the eye (23.9%), whereas infection and inflammation of the anterior segment were the most common causes in 2019 (35.5%). Urgency by AAO standards was in agreement in 26.7% admissions in 2019 and 35.6% in 2020 (p=0.0002). CONCLUSION: The COVID-19 pandemic has influenced several aspects of the OER, including the number of referrals, type of ophthalmic emergency, the time spent in the OER, and the need for emergent treatment. Our change in the treatment algorithm was in agreement with the AAO recommendations during the pandemic.