TY - JOUR
T1 - Blood-retinal barrier glycerol permeability in diabetic macular edema and healthy eyes: estimations from macular volume changes after peroral glycerol
AU - Thornit, Dorte Nellemann
AU - Vinten, Carl Martin
AU - Sander, Birgit
AU - Lund-Andersen, Henrik
AU - la Cour, Morten
AU - Thornit, Dorte Nellemann
AU - Vinten, Carl Martin
AU - Sander, Birgit
AU - Lund-Andersen, Henrik
AU - la Cour, Morten
N1 - Keywords: Aged; Biological Transport; Blood Pressure; Blood-Retinal Barrier; Body Water; Capillary Permeability; Creatinine; Diabetic Retinopathy; Female; Glycerol; Hemoglobin A, Glycosylated; Humans; Macular Edema; Male; Middle Aged; Models, Theoretical; Osmolar Concentration; Prospective Studies; Retina; Tomography, Optical Coherence; Visual Acuity
PY - 2010/6/1
Y1 - 2010/6/1
N2 - PURPOSE. To compare the changes in macular volume (MV) between healthy subjects and patients with diabetic macular edema (DME) after an osmotic load and to determine the glycerol permeability (Pgly) of the blood-retinal barrier (BRB). METHODS. In this unmasked study, 13 patients with DME and 5 healthy control subjects ingested a glycerol solution (0.57 g/mL) of 3 mL/kg body weight (maximum, 250 mL). Subsequently, the MV determined by the retinal maps provided by the optical coherence tomography (OCT) fast macular thickness protocol was monitored at 12 time points for 180 minutes. A mathematical model of glycerol and osmotic water movements across the BRB was constructed to estimate Pgly. RESULTS. Median MV decreased from 7.30 mm33 (range, 6.68- 7.35) to the maximum median ΔMV of -0.30 mm33 (25%-75% quartile: -0.34 to -0.25) in the healthy volunteers and from 7.97 mm33 (range, 6.85-9.89) to ΔMV of _0.14 mm33 (25%-75% quartile: -0.19 to -0.08) in the diabetic group (intergroup difference: P< 0.05). Pgly was 6.1 × 10-6 (SE 1.8 × 10-6) and 74 × 10-6 (SE 42 × 10-6) cm/s in the healthy and diabetic participants, respectively (P × 0.0001). No rebound phenomenon was observed in either group. CONCLUSIONS. The maximum reduction in MV was doubled in the healthy group compared with the diabetic group, whereas the glycerol permeability was 12 times higher in the diabetic participants. These findings confirm the paradigm of BRB breakdown in DME, but also suggest a novel procedure for the determination of retinal permeability to various agents, which is independent of the vitreous condition (ClinicalTrials.gov number, NCT00333671).
AB - PURPOSE. To compare the changes in macular volume (MV) between healthy subjects and patients with diabetic macular edema (DME) after an osmotic load and to determine the glycerol permeability (Pgly) of the blood-retinal barrier (BRB). METHODS. In this unmasked study, 13 patients with DME and 5 healthy control subjects ingested a glycerol solution (0.57 g/mL) of 3 mL/kg body weight (maximum, 250 mL). Subsequently, the MV determined by the retinal maps provided by the optical coherence tomography (OCT) fast macular thickness protocol was monitored at 12 time points for 180 minutes. A mathematical model of glycerol and osmotic water movements across the BRB was constructed to estimate Pgly. RESULTS. Median MV decreased from 7.30 mm33 (range, 6.68- 7.35) to the maximum median ΔMV of -0.30 mm33 (25%-75% quartile: -0.34 to -0.25) in the healthy volunteers and from 7.97 mm33 (range, 6.85-9.89) to ΔMV of _0.14 mm33 (25%-75% quartile: -0.19 to -0.08) in the diabetic group (intergroup difference: P< 0.05). Pgly was 6.1 × 10-6 (SE 1.8 × 10-6) and 74 × 10-6 (SE 42 × 10-6) cm/s in the healthy and diabetic participants, respectively (P × 0.0001). No rebound phenomenon was observed in either group. CONCLUSIONS. The maximum reduction in MV was doubled in the healthy group compared with the diabetic group, whereas the glycerol permeability was 12 times higher in the diabetic participants. These findings confirm the paradigm of BRB breakdown in DME, but also suggest a novel procedure for the determination of retinal permeability to various agents, which is independent of the vitreous condition (ClinicalTrials.gov number, NCT00333671).
U2 - 10.1167/iovs.09-4172
DO - 10.1167/iovs.09-4172
M3 - Journal article
C2 - 20042642
SN - 0146-0404
VL - 51
SP - 2827
EP - 2834
JO - Investigative Ophthalmology & Visual Science
JF - Investigative Ophthalmology & Visual Science
IS - 6
ER -