Infection, oxygen, and immaturity: interacting risk factors for retinopathy of prematurity.

BACKGROUND: Interactions among known risk factors for retinopathy of prematurity (ROP) remain to be clarified. OBJECTIVES: The aim of this study was to identify risk factors associated with ROP and to explore the interrelationships between prominent risk factors for ROP. METHODS: From an institutional cohort of 1,646 very preterm newborns with gestational age <30 weeks or birth weight <1,501 g, we selected infants with a gestational age <30 weeks who met the criteria for ROP screening (n = 622) for a nested case-control analysis. RESULTS: Of the 622 eligible newborns, 293 (47%) were diagnosed with ROP. From multivariable analyses, gestational age <26 weeks (OR 2.9, CI 1.7-4.9), oxygen exposure at 28 days (OR 1.7, CI 1.0-2.7), and neonatal sepsis (OR 2.1, CI 1.4-3.2) emerged as prominent risk factors for ROP. Oxygen- associated ROP risk was more prominent among infants of 23-25 weeks' gestational age, while infection-associated ROP risk was higher among infants born at 28-29 weeks. The OR for the joint effect of all 3 risk factors (23.5) was higher than would have been expected under the additive (8.6) and the multiplicative (16.5) patterns of interaction. CONCLUSIONS: Our study suggests that neonatal sepsis, oxygen exposure, and low gestational age are not only independently associated with a significantly increased risk of ROP, but also interact beyond additive and even multiplicative patterns.

Cystoid macular edema without macular thickening: a retrospective optical coherence tomographic study.

BACKGROUND: This is a retrospective observational case series of 37 eyes of 32 patients meeting the inclusion criteria intended to describe the appearance, prevalence, and associated risk factors for cystoid macular edema in eyes with normal foveal thickness and contour as determined by optical coherence tomography (OCT). METHODS: A retrospective review of all patients with macular disease who underwent OCT evaluation at the New England Eye Center from January to March 2007 and met the study inclusion criteria was performed. Optical coherence tomography scans were evaluated for the presence of intraretinal cystic fluid or cystoid macular edema but with normal retinal thickness and foveal contour. Retinal thickness and contour were evaluated using OCT mapping software. The main outcome measures were as follows: OCT-defined entity based on the presence of cystoid spaces within the fovea, "normal" foveal thickness (<252 microm), normal foveal contour, and best-corrected visual acuity on the date of examination. RESULTS: Thirty-seven eyes of 32 patients were determined to have cystoid macular edema with normal foveal thickness and contour on OCT. The overall prevalence within our patient population was 4.9%. Mean foveal thickness (standard deviation) for these patients was 201.4 microm (28.9) compared with normal mean foveal thickness (standard deviation) of 212 microm (20.0). Of the 32 patients, 17 (53.1%) had a primary diagnosis of age-related macular degeneration. The mean visual acuity (Snellen; logarithm of the minimum angle of resolution) was 20/80 (0.60). CONCLUSION: Cystoid macular edema in the setting of normal foveal thickness and contour as determined by OCT has not been extensively described. This entity is not pathognomonic of a single diagnosis and can occur in the setting of several disparate diagnoses as seen in our cohort. Chief among these were age-related macular degeneration and diabetic retinopathy. Acute postcataract cystoid macular edema was absent.

Noninsertional Achilles tendinopathy: pathology and management.

Many patients present to their physician's office with the chief complaint of pain at the Achilles tendon. This review discusses the pathology, diagnosis, and treatment of Achilles tendinopathy. Achilles tendinopathy is generally caused by chronic stress to the tendon, leading to a defective arrangement of collagen fibers in the Achilles tendon. This then results in pain and limited function. Ultrasound imaging can help identify the abnormal portion of the tendon. Various treatments are available for Achilles tendinopathy, the most current of which are discussed in this article. Appropriate treatment can potentially lead to a full recovery.

Matrix metalloproteinase gelatinase B (MMP-9) coordinates and effects epithelial regeneration.

We studied the role of the matrix metalloproteinase gelatinase B (gelB; MMP-9) in epithelial regeneration using the gelB-deficient mouse. We report the novel finding that, in contrast to other MMPs expressed at the front of the advancing epithelial sheet in wounds of cornea, skin, or trachea, gelB acts to inhibit the rate of wound closure. We determined this to be due to control of cell replication, a novel capacity for MMPs not previously described. We also found that gelB delays the inflammatory response. Acceleration of these processes in gelB-deficient mice is correlated with a delay in signal transduction through Smad2, a transcription factor that inhibits cell proliferation, and in accumulation of epithelial-associated interleukin-1alpha, a cytokine that inhibits Smad2 signaling and promotes the inflammatory response. GelB-deficient mice also reveal defects in remodeling of extracellular matrix at the epithelial basement membrane zone, in particular, failure to effectively remove the fibrin(ogen) provisional matrix. We conclude that gelB coordinates and effects multiple events involved in the process of epithelial regeneration.