Analysis of Retinochoroidal Vasculature in Underweight Women Using Optical Coherence Tomography Angiography

Cachectic patients and controls undergoing a comprehensive ophthalmologic examination. The imaging of all subjects is undertaken using a commercial OCTA device with a scan rate of 70,000 A-scans/s, scan beam wavelength of 840 ± 10 nm and bandwidth of 45 nm. All measurements are performed between 10:00 and 12:00 on the same day. The OCTA images are independently graded and assessed by two retinal specialists. The software automatically segmented these full-thickness retinal scans into the superficial and deep inner retinal vascular plexuses, outer retina, and choriocapillaris (CC). The vascular density in the superficial and deep retinal vascular zones is calculated automatically by the software, and the foveal avascular zone (FAZ) and foveal density (FD) are also automatically determined. Choroidal thickness is calculated manually by two retinal specialists, and the average value was used.

Study Overview

• Status: Completed
• Conditions: Cachexia; Underweight
• Intervention / Treatment: Diagnostic test: Comprehensive ophthalmologic examination

Detailed Description

Cachectic patients and controls undergoing a comprehensive ophthalmologic examination, including the measurements of best-corrected visual acuity (BCVA), refractive error (KR-8900; Topcon, Tokyo, Japan), intraocular pressure (IOP, Full Auto Tonometer TX-F; Topcon), axial length (AL, Lenstar LS 900, Haag-Streit AG, Switzerland), slit lamp examination of the anterior segment, dilated fundus examination, and OCTA imaging (Optovue RTVue XR 100 Avanti, Freemont, California, USA) are included in the study. To calculate BMI, height is measured using a standard anthropometric tape (Bioplus Stature Meter, model number IND/09/2005/815), and a certified electronic weighing scale (model number Omron HN-283) is used to measure weight.

According to the national guidelines, the patients are classified into two underweight groups: Group 1 consisting of those with a BMI of <17.00 kg/m2 and Group 2 comprising those with a BMI of 17.00 to 18.49 kg/m2. The control group is formed with individuals with a normal BMI (18.50 to 24.99 kg/m2).

The right eye of each participant is included in the study. If the right eye meets any of the exclusion criteria, then the left eye is selected for the sample. The inclusion criteria for the patient group is being underweight (BMI < 18.50 kg/m2). The exclusion criteria for all groups are as follows: refractive error >+3.0 diopters (D) or <-3.0 D spherical equivalent; poor image quality <60 due to unstable fixation; IOP > 21 mm Hg; longer AL (>25 mm); pre-existing ophthalmic pathologies; prior ocular surgery; and a systemic chronic disease that can cause underweight or retinopathy, such as cancer, malnutrition, and diabetes mellitus.

OCTA

The imaging of all subjects is undertaken using a commercial OCTA device with a scan rate of 70,000 A-scans/s, scan beam wavelength of 840 ± 10 nm and bandwidth of 45 nm. This device can perform 70 000 A-scans/s per second to acquire volumes of 304 × 304 A-scans. All measurements are performed between 10:00 and 12:00 on the same day.

To evaluate the vascular structures, 6×6 mm OCTA software is used. The split-spectrum amplitude decorrelation angiography (SSADA) algorithm is performed in all participants. The images of poor quality (signal strength index (SSI) < 8) with either significant motion artifact or incorrect segmentation are excluded. The OCTA images are independently graded and assessed by two retinal specialists. The software automatically segmented these full-thickness retinal scans into the superficial and deep inner retinal vascular plexuses, outer retina, and choriocapillaris (CC). The vascular density in the superficial and deep retinal vascular zones is calculated automatically by the software, and the foveal avascular zone (FAZ) and foveal density (FD) are also automatically determined. The same software also calculates the flow index rates in a central circular zone of 3.144 mm² in the outer retina and CC segments. Choroidal thickness is calculated manually by two retinal specialists, and the average value was used.

• Study Type: Observational
• Enrollment (Actual): 48

Contacts and Locations

Study Locations

• Turkey
  • Antalya, Turkey, 070059
    • Aslı Çentinkaya Yaprak

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 40 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Study population includes a convenience sampling from the patients admitted to outpatient clinic between June 2020 and August 2020.

Description

Inclusion Criteria:

• Underweight (BMI < 18.50 kg/m2).

Exclusion Criteria:

• refractive error >+3.0 diopters (D) or <-3.0 D spherical equivalent;
• poor image quality <60 due to unstable fixation
• IOP > 21 mm Hg
• longer AL (>25 mm)
• pre-existing ophthalmic pathologies
• prior ocular surgery
• a systemic chronic disease that can cause underweight or retinopathy, such as cancer, malnutrition, and diabetes mellitus.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Control; Comprehensive ophthalmologic examination	Diagnostic test: Comprehensive ophthalmologic examination; Measurements of best-corrected visual acuity, refractive error, intraocular pressure, axial length, slit lamp examination of the anterior segment, dilated fundus examination, and optical coherence tomography angiography imaging.
Underweight; Comprehensive ophthalmologic examination	Diagnostic test: Comprehensive ophthalmologic examination; Measurements of best-corrected visual acuity, refractive error, intraocular pressure, axial length, slit lamp examination of the anterior segment, dilated fundus examination, and optical coherence tomography angiography imaging.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Choriocapillaris flow area	Choriocapillaris flow area assessed with optical coherence tomography angiography	10 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Subfoveal choroidal thickness	Subfoveal choroidal thickness assessed with optical coherence tomography angiography	10 minutes
Foveal avascular zone	Foveal avascular zone assessed with optical coherence tomography angiography	10 minutes
Subfoveal central macular thickness	Subfoveal central macular thickness assessed with optical coherence tomography angiography	10 minutes
Vessel density	Vessel density assessed with optical coherence tomography angiography	10 minutes

Collaborators and Investigators

• Sponsor: Akdeniz University

Study record dates

Study Major Dates

• Study Start (ACTUAL): June 1, 2020
• Primary Completion (ACTUAL): August 30, 2020
• Study Completion (ACTUAL): August 30, 2020

Study Registration Dates

• First Submitted: November 11, 2020
• First Submitted That Met QC Criteria: November 11, 2020
• First Posted (ACTUAL): November 17, 2020

Study Record Updates

• Last Update Posted (ACTUAL): November 18, 2020
• Last Update Submitted That Met QC Criteria: November 17, 2020
• Last Verified: November 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Body Weight; Body Weight Changes; Emaciation; Weight Loss; Cachexia; Thinness
• Other Study ID Numbers: 19102017-15/4-184

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No