Prognosis of primary rhegmatogenous retinal detachments. 1. Associations between clinical detachment characteristics, subretinal fluid butyrylcholinesterase and visual outcome following scleral buckling procedures

Preoperative Optical Coherence Tomography Findings of Foveal-Splitting Rhegmatogenous Retinal Detachment

PURPOSE

To assess preoperative optical coherence tomography (OCT) findings of foveal-splitting retinal detachment (RD) and determine postoperative outcomes.

METHODS

Consecutive patients who underwent RD surgery over a 1-year period were included. Patients diagnosed with a detachment extending to the edge of the fovea on fundus examination (i.e., macula-On/Off) underwent macular OCT scanning. Visual acuity (VA) after 1 year of macula-On/Off, macula-On, and macula-Off eyes was compared.

RESULTS

A total of 85 eyes were included, 8 of which had a macula-On/Off RD. On preoperative OCT, all macula-On/Off RD eyes had foveal detachment extending beyond the foveal center over a median distance of 632 µm. Mean VA of the macula-On/Off eyes had improved from 20/160 to 20/40 at 1 year postoperatively (p = 0.035). The preoperative VA of macula-On/Off eyes was significantly better than macula-Off eyes (p = 0.032) and lower than macula-On eyes (p = 0.004). At 1 year, the VA of macula-On/Off eyes was no different from that of the macula-On eyes (p = 0.320), and tended to be better than that of the macula-Off eyes (p = 0.062).

CONCLUSION

Preoperative OCT revealed a shallow RD extending beyond the foveal center in eyes with clinical foveal-splitting RD. These eyes, termed macula-On/Off RD eyes, had a preoperative VA between macula-On and macula-Off eyes, while their final VA was close to those with macula-On RD.

Deconstructing aqueous humor outflow - The last 50 years

Herein partially summarizes one scientist-clinician's wanderings through the jungles of primate aqueous humor outflow over the past ~45 years. Totally removing the iris has no effect on outflow facility or its response to pilocarpine, whereas disinserting the ciliary muscle (CM) from the scleral spur/trabecular meshwork (TM) completely abolishes pilocarpine's effect. Epinephrine increases facility in CM disinserted eyes. Cytochalasins and latrunculins increase outflow facility, subthreshold doses of cytochalasins and epinephrine given together increase facility, and phalloidin, which has no effect on facility, partially blocks the effect of both cytochalasins and epinephrine. H-7, ML7, Y27632 and nitric oxide - donating compounds all increase facility, consistent with a mechanosensitive TM/SC. Adenosine A1 agonists increase and angiotensin II decrease facility. OCT and optical imaging techniques now permit visualization and digital recording of the distal outflow pathways in real time. Prostaglandin (PG) F2α analogues increase the synthesis and release of matrix metalloproteinases by the CM cells, causing remodeling and thinning of the interbundle extracellular matrix (ECM), thereby increasing uveoscleral outflow and reducing IOP. Combination molecules (one molecule, two or more effects) and fixed combination products (two molecules in one bottle) simplify drug regimens for patients. Gene and stem cell therapies to enhance aqueous outflow have been successful in laboratory models and may fill an unmet need in terms of patient compliance, taking the patient out of the delivery system. Functional transfer of genes inhibiting the rho cascade or decoupling actin from myosin increase facility, while genes preferentially expressed in the glaucomatous TM decrease facility. In live NHP, reporter genes are expressed for 2+ years in the TM after a single intracameral injection, with no adverse reaction. However, except for one recent report, injection of facility-effective genes in monkey organ cultured anterior segments (MOCAS) have no effect in live NHP. While intracameral injection of an FIV. BOVPGFS-myc.GFP PGF synthase vector construct reproducibly induces an ~2 mmHg reduction in IOP, the effect is much less than that of topical PGF2⍺ analogue eyedrops, and dissipates after 5 months. The turnoff mechanism has yet to be defeated, although proteasome inhibition enhances reporter gene expression in MOCAS. Intracanalicular injection might minimize off-target effects that activate turn-off mechanisms. An AD-P21 vector injected sub-tenon is effective in 'right-timing' wound healing after trabeculectomy in live laser-induced glaucomatous monkeys. In human (H)OCAS, depletion of TM cells by saponification eliminates the aqueous flow response to pressure elevation, which can be restored by either cultured TM cells or by IPSC-derived TM cells. There were many other steps along the way, but much was accomplished, biologically and therapeutically over the past half century of research and development focused on one very small but complex ocular apparatus. I am deeply grateful for this award, named for a giant in our field that none of us can live up to.

Binocular visual function after surgery for detached retina

Binocular visual function after surgery for detached retina was examined in 100 patients with a visual acuity of less than 0.3 in the reattached retina and with a visual acuity of more than 1.0 in the non-detached retina: 1) There was no significant sex difference in binocular visual function. 2) There was no significant difference in binocular visual function according to postoperative interval. 3) Maintenance of postoperative binocular visual function was best in patients under 19 years of age, and grew worse with age. 4) In patients with a visual acuity of more than 0.1 in the reattached retina, simultaneous perception was good in 100%, and fusion in more than 80%. However, stereopsis was worse in most cases. 5) In patients with a visual acuity of less than 0.1 in the reattached retina, all aspects of binocular visual function were worse, except in those under 19 years of age. 6) There was no significant difference in binocular visual function between patients with and without temporary amputation of extrinsic ocular muscles at operation. 7) There was no significant difference in binocular visual function between patients with and without macular detachment before operation. 8) In the patients who had had an encircling operation, binocular visual function was worse than in those operated on with other procedures, because the former had the severest retinal detachment.

Prognosis for central vision and anatomic reattachment in rhegmatogenous retinal detachment with macula detached

We analyzed a total of 473 eyes with rhegmatogenous retinal detachment and macular involvement for significant factors relating to anatomic success and a favorable visual outcome of 6/15 (20/50) or better. The overall success rate was 90% (427 of 473 eyes). Visual acuities of 6/15 (20/50) or better postoperatively were present in 37% (174 of 470 eyes). Important factors related to both anatomic success and favorable functional results were preoperative visual acuities of 6/15 (20/50) or better, retinal detachments that were less than total, detachments with tears located at or anterior to the equator, absence of giant retinal tears, absence of either preoperative ocular hypotony (tension less than 5 mm Hg) or ocular hypertension (intraocular pressure greater than 20 mm Hg), detachments managed by nondrainage techniques, a single operation with less than 50 cryoapplications, and noncircumferential buckling. Among the other factors related to favorable visual results were detachments lasting less than one month, a shallowly rather than highly detached macula, the absence of fixed retinal folds, a patient age of less than 60 years, and the absence of postoperative choroidal detachments sufficient to cause glaucoma. We found no statistical relationship between either anatomic success or functional result and the presence of aphakia, demarcation lines, vitreous hemorrhage, detachments of the pars plana epithelium, or predetachment glaucoma being treated.

Rhegmatogenous retinal detachment without macular involvement treated with scleral buckling

Among 173 patients who had rhegmatogenous retinal detachment with spared maculas, high percentage achieved anatomic and functional success. We reattached 171 (99%) of the retinas; 150 (76%) of the eyes had final visual acuities of 6/15 (20/50) or better. Eighteen eyes (10%) had final postoperative visual acuities reduced more than two lines from the preoperative level. This reduced visual acuity was primarily related to postoperative changes occurring in the macula. The prognosis both for anatomic reattachment and visual acuity after scleral buckling for rhegmatogenous retinal detachment is significantly better when the macula is spared than when it is not. Large numbers of cryoapplications were not associated with macular complications.

Prognosis of primary rhegmatogenous retinal detachments. 2. Accounting for and predicting final visual acuity in surgically reattached cases

Multiple linear regression-analysis of variance was used to define relationships between final visual acuity and several parameters in 31 patients with reattached primary rhegmatogenous retinal detachments. Older patient age, preoperative macular detachment, clinically visible macular lesions, greater detachment duration and extent, and higher subretinal fluid butyrylcholinesterase activity were all inversely related to final acuity. The relationship of each parameter to final acuity, in conjunction with and apart from all the other parameters, was defined. Collectively the parameters accounted for 85% of the variation about the mean of the clinically observed finally acuities. The parameters could be weighted to give a generally, reasonably accurate prediction of final acuity at the time of surgery. The findings are consistent with a pathophysiological sequence involving alterations in the choroidal circulation and the blood-ocular barrier of the posterior segment.