Retinal detachment and proliferative vitreoretinopathy: central retinal artery blood velocities, intraocular pressure, and endothelin 1.

PURPOSE: To analyze if endothelin 1 may have an effect on central retinal artery (CRA) blood flow velocities and intraocular pressure (IOP) in retinal detachment. METHODS: Using radioimmunoassay, immunoreactive endothelin 1 levels were tested in both plasma and subretinal fluid specimens from patients with retinal detachment, while only plasma specimens from healthy subjects were tested. Central retinal artery Doppler sonography parameters and IOP were measured in eyes with retinal detachment, with and without proliferative vitreoretinopathy, their respective healthy fellow eyes, and normal eyes. RESULTS: Retinal detachment eyes had lower CRA peak systolic velocity and end-diastolic velocity, lower IOP, and higher plasma immunoreactive endothelin 1 levels than normal eyes (P < 0.0001). Eyes with proliferative vitreoretinopathy had lower CRA peak systolic velocity and end-diastolic velocity, higher resistivity index, lower IOP, higher plasma immunoreactive endothelin 1 levels, and higher subretinal fluid immunoreactive endothelin 1 than eyes without proliferative vitreoretinopathy (P < 0.0001). A statistically significant linear correlation was found among CRA parameters, IOP, and subretinal fluid immunoreactive endothelin 1 measurements. CONCLUSION: Endothelin 1 has shown a close relationship with IOP and CRA blood flow changes associated to retinal detachment as well as with proliferative vitreoretinopathy complications.

Preoperative duration of retinal detachment and preoperative central retinal artery hemodynamics: repercussion on visual acuity.

PURPOSE: To analyze if preoperative duration of primary rhegmatogenous retinal detachment (RD) influences preoperative central retinal artery (CRA) hemodynamics with repercussions on logarithmic (LogMAR) visual acuity (VA). METHODS: Prospective clinical cohort study on 66 healthy patients (33 with proliferative vitreoretinopathy (PVR) and 33 with no PVR) with unilateral RD candidates for scleral buckling (SB) surgery (PVR

Retinal detachment and proliferative vitreoretinopathy: ophthalmic artery blood velocities, intraocular pressure, and endothelin-1.

PURPOSE: To analyze if endothelin-1 (ET-1) may have an effect on ophthalmic artery (OA) blood flow velocities and intraocular pressure (IOP) in retinal detachment (RD). METHODS: Using radioimmunoassay, immunoreactive (IR) ET-1 levels were tested in both plasma and subretinal fluid (SRF) specimens from patients with RD, while only plasma specimens from normal (healthy) subjects were tested. OA Doppler sonography parameters and IOP were measured in eyes with RD, with and without proliferative vitreoretinopathy (PVR), their respective healthy fellow eyes, and normal eyes. RESULTS: RD eyes had lower OA peak systolic velocity (PSV) and end diastolic velocity (EDV), higher resistivity index (RI), lower IOP, and higher plasma IR ET-1 levels than normal eyes (P < 0.0001). Eyes with PVR had lower OA PSV and EDV, higher RI, lower IOP, higher plasma IR ET-1 levels, and higher SRF IR ET-1 than eyes without PVR (P < 0.0001). A statistically significant linear correlation was found among OA parameters, IOP, and SRF IR ET-1 measurements. CONCLUSIONS: Decreased OA blood flow velocities may explain lower IOP found in RD patients, and ET-1 levels may be responsible for both measurements.

MIRAgel: hydrolytic degradation and long-term observations.

OBJECTIVE: To analyze long-term complications of hydrogel (MIRAgel; MIRA Inc, Waltham, Mass) explants. DESIGN: Institutional clinical study of a retrospective, interventional case series of patients. We included 415 patients with complete reattachment of the retina 6 months after surgery and up-to-date follow-up. Patients underwent ophthalmological examination at each visit (mean follow-up, 187 months), and 6 underwent computed tomography and/or magnetic resonance imaging. Main outcome measures included the MIRAgel explant removal rate, clinical manifestations related to removal, interval from the start of discomfort to removal, mean time from implantation to removal, culture yield of the removed elements, results of histological examination of the capsule surrounding the removed explants (12 cases), and micro-Fourier transform infrared spectroscopic analysis results of 3 recovered explants. RESULTS: MIRAgel explant removal was necessary in 27 (6.5%) of 415 patients who received MIRAgel material and in 27 (7.6%) of 357 patients who had had it for 7 or more years. Clinical manifestations were related to swelling of the MIRAgel material, with a mean interval of 15 (range, 6-22) months from starting symptoms to removal. The infrared spectroscopic analysis demonstrated the presence of carboxylic groups in 3 recovered explants that had swollen considerably. CONCLUSION: Prompt removal of MIRAgel explants when discomfort starts should be considered to avoid increased incidence of complications.