Simpson, Andrew R H, Dowell, Nicholas G, Jackson, Timothy L, Tofts, Paul S and Hughes, Edward H (2013) Measuring the effect of pars plana vitrectomy on vitreous oxygenation using magnetic resonance imaging. Investigative Ophthalmology & Visual Science, 54 (3). pp. 2028-2034. ISSN 0146-0404
Full text not available from this repository.Abstract
PURPOSE
To study the effect of pars plana vitrectomy (PPV) on vitreous oxygenation (pO2) using magnetic resonance imaging (MRI).
METHODS
Patients due to undergo PPV for either macular hole or epiretinal membrane were recruited. MRI scanning was performed 1 week before and at least 3 months after PPV. MRI T1 mapping was performed using an inversion recovery-true fast imaging with steady-state precession (TrueFISP) sequence at several inversion times, from a single slice positioned through the center of both eyes in the axial oblique plane. Additional phantom data were measured in porcine vitreous, to define the relationships between T1 relaxation times and balanced salt solution (BSS), to simulate human vitreous and aqueous, respectively, for a suitable pO2 range (5-70 mm Hg). Pre-PPV pO2 was also measured intraoperatively using a polarographic oxygen probe.
RESULTS
Eleven participants (age range 59-84) were recruited; two declined the post-PPV scan. Corrected T1 times indicated that the mean (±SD) pO2 increased significantly following PPV, from 13.2 ± 5.8 to 34.5 ± 8.0 mm Hg (P < 0.001). In the nonsurgical (control) eye, pO2 did not change significantly from the first to second MRI scan (13.7 ± 7.8 vs. 16.3 ± 8.7 mm Hg, P = 0.239). Mean pO2 measured intraoperatively was 7.2 ± 0.6 mm Hg (n = 10).
CONCLUSIONS
These results confirm that vitrectomy substantially increases vitreous pO2. MRI is a noninvasive technique that can be used to study vitreous oxygenation in both vitrectomized and nonvitrectomized eyes.
Item Type: | Article |
---|---|
Schools and Departments: | Brighton and Sussex Medical School > Neuroscience Brighton and Sussex Medical School > Clinical and Experimental Medicine |
Subjects: | R Medicine > R Medicine (General) > R895 Medical physics. Medical radiology. Nuclear medicine R Medicine > RC Internal medicine > RC0071 Examination. Diagnosis Including radiography > RC0078 Radiography. General works > RC0078.7.D53 Diagnostic imaging R Medicine > RE Ophthalmology |
Depositing User: | Nicholas Dowell |
Date Deposited: | 26 Mar 2013 08:52 |
Last Modified: | 05 Oct 2017 18:26 |
URI: | http://sro.sussex.ac.uk/id/eprint/44117 |