Synthetic MRI demonstrates prolonged regional relaxation times in the brain of preterm born neonates with severe postnatal morbidity.

BACKGROUND: To identify preterm infants at risk for neurodevelopment impairment that might benefit from early neurorehabilitation, early prognostic biomarkers of future outcomes are needed. OBJECTIVE: To determine whether synthetic MRI is sensitive to age-related changes in regional tissue relaxation times in the brain of preterm born neonates when scanned at term equivalent age (TEA, 37-42 weeks), and to investigate whether severe postnatal morbidity results in prolonged regional tissue relaxation times. MATERIALS AND METHODS: This retrospective study included 70 very preterm born infants scanned with conventional and synthetic MRI between January 2017 and June 2019 at TEA. Infants with severe postnatal morbidity were allocated to a high-risk group (n = 22). All other neonates were allocated to a low-risk group (n = 48). Linear regression analysis was performed to determine the relationship between relaxation times and postmenstrual age (PMA) at scan. Analysis of covariance was used to evaluate the impact of severe postnatal morbidity in the high-risk group on T1 and T2 relaxation times. Receiver operating characteristic (ROC) curves were plotted and analysed with area under the ROC curve (AUC) to evaluate the accuracy of classifying high-risk patients based on regional relaxation times. RESULTS: A linear age-related decrease of T1 and T2 relaxation times correlating with PMA at scan (between 37 and 42 weeks) was found in the deep gray matter, the cerebellum, the cortex, and the posterior limb of the internal capsule (PLIC) (p < .005 each), but not in the global, frontal, parietal, or central white matter. Analysis of covariance for both risk groups, adjusted for PMA, revealed significantly prolonged regional tissue relaxation times in neonates with severe postnatal morbidity, which was best illustrated in the central white matter of the centrum semiovale (T1 Δ = 11.5%, T2 Δ = 13.4%, p < .001) and in the PLIC (T1 Δ = 9.2%, T2 Δ = 6.9%, p < .001). The relaxation times in the PLIC and the central white matter predicted high-risk status with excellent accuracy (AUC range 0.82-0.86). CONCLUSION: Synthetic MRI-based relaxometry in the brain of preterm born neonates is sensitive to age-related maturational changes close to TEA. Severe postnatal morbidity correlated with a significant delay in tissue relaxation. Synthetic MRI may provide early prognostic biomarkers for neurodevelopment impairment.

Tear Film, Lacrimal Drainage System, and Eyelid Findings in Subjects With Anophthalmic Socket Discharge.

PURPOSE: To compare the results of tear film and lacrimal drainage system tests between anophthalmic socket and normal eye and assess discharge characteristics and frequency of prosthesis removal (questionnaire), eyelid function, and meibomian glad dysfunction (MGD). DESIGN: Prospective masked case control. METHODS: Subjects (≥6 years and ≥6 months of wearing prosthesis) with unilateral acquired anophthalmic socket discharge were included. Excluded was ocular adnexal abnormality of any reason and incomplete tests. The subjective questionnaire was completed. Blinking rate, lagophthalmos, eyelid laxity, MGD, Schirmer test, tear meniscus height, and dye disappearance test were assessed by a masked examiner. Another masked examiner performed an irrigation test 1 week later and interpreted the scintigraphy images at the end of the study. RESULTS: Included were 50 subjects (mean age: 31.3 years, mean prosthesis wear: 96.1 months). Discharge was frequent or very frequent in 85%, mucoid or mucopurulent in 90%, and moderate to severe in 86% of the subjects. MGD in 58%, lagophthalmos in 80%, and eyelid laxity in 46% were observed. Anophthalmic socket sides showed a significantly lower tear production and higher tear drainage obstruction. Subjects with frequent prosthesis removal had a significantly (P = .02) greater lagophthalmos and blinking rate (P = .04). The blinking rate was also significantly greater in subjects with higher frequency of discharge (P = .04). CONCLUSION: Tear film impairment (aqueous and lipid) and lacrimal drainage obstruction should be considered in subjects with anophthalmic socket discharge. A significantly higher blinking rate and lagophthalmos were found in subjects with higher frequency of prosthesis removal.