Link to the University of Pittsburgh Homepage
Link to the University Library System Homepage Link to the Contact Us Form
D-Scholarship @ Pitt Banner and Links to Homepage

Regionally discrete aqueous humor outflow quantification using fluorescein canalograms

Loewen, RT and Brown, EN and Roy, P and Schuman, JS and Sigal, IA and Loewen, NA (2016) Regionally discrete aqueous humor outflow quantification using fluorescein canalograms. PLoS ONE, 11 (3).

[img]
Preview
 PDF
Published Version
Available under License : See the attached license file.
Download (5MB)
[img] Plain Text (licence)
Available under License : See the attached license file.
Download (1kB)

Abstract

Purpose To visualize and quantify conventional outflow directly in its anatomic location. Methods We obtained fluorescein canalograms in six porcine whole eyes and six porcine anterior segment cultures. Eyes were perfused with a constant pressure of 15 mmHg using media containing 0.017 mg/ml fluorescein. Flow patterns were visualized using a stereo dissecting microscope equipped for fluorescent imaging. Images were captured every 30 seconds for 20 minutes for time lapse analysis. Anterior chamber cultures were imaged again on day three of culture. Canalograms were first analyzed for filling time per quadrant. We then wrote a program to automatically compute focal flow fits for each macropixel and to detect convergent perilimbal flow patterns with macropixels grouped into 3 equal-radial width rings around the cornea. A generalized additive model was used to determine fluorescence changes of individual macropixels. Results The resulting imaging algorithm deployed 1024 macropixels that were fit to determine maximum intensity and time to fill. These individual fits highlighted the focal flow function. In whole eyes, significantly faster flow was seen in the inferonasal (IN) and superonasal (SN) quadrants compared to the superotemporal (ST) and inferotemporal (IT) ones (p<0.05). In anterior chamber cultures, reduced flow on day 1 increased in all quadrants on day 3 except in IT (p<0.05). Perilimbal ring analysis uncovered convergent perilimbal flow. Conclusions An algorithm was developed that analyzes regional and circumferential outflow patterns. This algorithm found flow patterns that changed over time and differ in whole eyes and anterior segment cultures.

Share

Citation/Export:
Social Networking:
Share |

Details

Item Type: Article
Status: Published
Creators/Authors:
CreatorsEmailPitt UsernameORCID
Loewen, RTrtl13@pitt.eduRTL13
Brown, EN
Roy, P
Schuman, JSjss28@pitt.eduJSS280000-0002-8885-3766
Sigal, IAian.sigal@pitt.eduIAS6
Loewen, NANAL58@pitt.eduNAL58
Contributors:
ContributionContributors NameEmailPitt UsernameORCID
EditorGonzalez, PedroUNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Centers: Other Centers, Institutes, Offices, or Units > Louis J. Fox Center for Vision Restoration
Date: 1 March 2016
Date Type: Publication
Access Restriction: No restriction; Release the ETD for access worldwide immediately.
Journal or Publication Title: PLoS ONE
Volume: 11
Number: 3
DOI or Unique Handle: 10.1371/journal.pone.0151754
Institution: University of Pittsburgh
Schools and Programs: School of Medicine > Ophthalmology
Refereed: Yes
Date Deposited: 23 Aug 2016 15:12
Last Modified: 30 Mar 2021 15:55
URI: http://d-scholarship.pitt.edu/id/eprint/28291

Metrics

Monthly Views for the past 3 years

Plum Analytics

Altmetric.com

Actions (login required)

View Item View Item