Smartphone Ophthalmoscope of Lens Vascularity to Estimate Gestational Age

Gestational Age Clinical Trial

Official title:

Smartphone Ophthalmoscope Lens Vascularity Estimated Gestational Age (SOLVE-GA)

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02346214
• Other study ID #: OPP1119360
• Status: Completed
• Phase: N/A
• First received: January 20, 2015
• Last updated: January 12, 2018
• Start date: July 2016
• Est. completion date: November 30, 2017

Study information

• Verified date: January 2018
• Source: RTI International
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The purpose of this study is to develop a novel, highly automated method of gestational age estimation at delivery combining anterior lens capsule vascularity (ALCV) and biophysical parameters appropriate for use in low income countries. The specific aims of the proposed study are: (1) To develop an algorithm to predict gestational age at delivery from 26 to 42 weeks' gestation with ALCV and key biophysical parameters (2)To evaluate the performance of ALCV and biophysical parameter-based gestational age estimates. Specifically, we hypothesize that the accuracy of the predictive algorithm will be comparable to commonly used measures of gestational age dating (±2 days) and have better precision (±14 days) than commonly used measures of gestational age dating.

Description:

Postnatal gestational age dating methods are needed in low/middle income settings as ultrasound is often unavailable, last menstrual dates uncertain, and physical/neurological scoring complex. The disappearance of anterior lens capsule vascularity (ALCV), a normal embryological process, has a high correlation with gestational age at delivery among preterm neonates. We will use an observational method-comparison study to establish the validity of smartphone ophthalmoscope ALCV gestational age estimates among preterm infants at delivery compared to the referent standard of ultrasound gestational age estimates. Study objectives and methods include the following: Objective 1. Develop an ALCV biomarker dataset from smartphone ophthalmoscope images using automated image analysis software. The dataset will include image features including: vessel quantity, lens clearing, tortuosity, vessel thickness, and branching angles and coefficients. Methods: (1) capture ALCV images via smartphone ophthalmoscope within 24 hours of delivery, and (2) segment ALCV images using software developed for the assessment of retinal vasculature. Proposed software will convert images into graphs and automatically find the vasculature based on the Dijkstra's shortest-path algorithm. The proposed software is tested for video-indirect neonatal ophthalmoscope images. Objective 2. Develop an algorithm to predict gestational age at delivery from 26 to 42 weeks' gestation with the ALCV biomarker dataset combined with key neonatal biophysical measures. Methods: (1) conduct descriptive and univariate analyses of predictors and assess linear model assumptions, and (2) fit a constrained linear regression model by selecting and shrinking estimated model coefficients from a fully specified model in the original sample to optimize predictive accuracy and model parsimony. Objective 3. Assess the performance of ALCV gestational age estimates compared to referent standard ultrasound estimates. Methods: (1) compare distributions of gestational age and the mean difference in days between dating methods, (2) test agreement between dating methods using Lin's concordance correlation coefficient and Bland-Altman plots with limits of agreement (3) internally validate test agreement using a bootstrap procedure for optimism correction of the agreement statistics. All statistical analyses will be performed in SAS 9.4 (SAS, Cary, North Carolina, USA).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 252
• Est. completion date: November 30, 2017
• Est. primary completion date: November 30, 2017
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: N/A to 24 Hours

Eligibility

Inclusion Criteria:

• Gestational age 260/7 to 426/7 weeks (based on antenatal ultrasound <20 weeks gestation)

• Chronological age <24 hours

• Consent of the patient's parents or legal guardians

Exclusion Criteria:

• Fused eyelids

• Corneal opacity or cataract

• Obstetrical ultrasound performed at <20 weeks' gestation not performed/not available

• Known genetic/congenital anomalies

• Known coagulopathies

• Patients who, in the opinion of the attending physician or clinical study staff, are too medically unstable to participate in the study safely

Related Conditions & MeSH terms

• Gestational Age

Locations

Country	Name	City	State
United States	University of North Carolina at Chapel Hill North Carolina Children's Hospital	Chapel Hill	North Carolina
United States	University of Iowa Children's Hospital	Iowa City	Iowa
United States	Loma Linda University Children's Hospital	Loma Linda	California

Sponsors (5)

Lead Sponsor	Collaborator
RTI International	Duke University, Loma Linda University, University of Iowa, University of North Carolina, Chapel Hill

Country where clinical trial is conducted

United States, 

References & Publications (8)

Altman, D. G. and J. M. Bland (1983).

Bland, J. M. and D. G. Altman (2010).

Blencowe H, Cousens S, Chou D, Oestergaard M, Say L, Moller AB, Kinney M, Lawn J; Born Too Soon Preterm Birth Action Group. Born too soon: the global epidemiology of 15 million preterm births. Reprod Health. 2013;10 Suppl 1:S2. doi: 10.1186/1742-4755-10-S1-S2. Epub 2013 Nov 15. Review. — View Citation

Concato, J., P. Peduzzi, T. R. Holford and A. R. Feinstein (1995). Estrada, R., C. Tomasi, M. T. Cabrera, D. K. Wallace, S. F. Freedman and S. Farsiu (2011).

Estrada R, Tomasi C, Cabrera MT, Wallace DK, Freedman SF, Farsiu S. Exploratory Dijkstra forest based automatic vessel segmentation: applications in video indirect ophthalmoscopy (VIO). Biomed Opt Express. 2012 Feb 1;3(2):327-39. doi: 10.1364/BOE.3.000327. Epub 2012 Jan 18. — View Citation

Hittner HM, Gorman WA, Rudolph AJ. Examination of the anterior vascular capsule of the lens: II. Assessment of gestational age in infants small for gestational age. J Pediatr Ophthalmol Strabismus. 1981 Mar-Apr;18(2):52-4. — View Citation

Hittner HM, Hirsch NJ, Rudolph AJ. Assessment of gestational age by examination of the anterior vascular capsule of the lens. J Pediatr. 1977 Sep;91(3):455-8. — View Citation

Nagpal J, Kumar A, Ramji S. Anterior lens capsule vascularity in evaluating gestation in small for gestation neonates. Indian Pediatr. 2004 Aug;41(8):817-21. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Anterior lens capsule vascularity estimated gestational age	The gestational age is estimated by eye lens vascularity measurement	Within 24 hours of delivery