Rhegmatogenous Detachment Research Articles

Human Subretinal Fluid

A light and electron microscopical study of subretinal fluid removed at surgery for rhegmatogenous retinal detachment showed a heterogeneity of cell types originating from the neural retina, pigment epithelium, and wandering cells of the blood. Subcellular organelles sedimenting in the centrifuged pellets could be identified as to cell of origin, health of the parent cell, and time since cell rupture. Acellular specimens were typical of angiomatous detachments or long-standing rhegmatogenous detachments. Because various mechanisms of cellular pathophysiology contribute to the destructive and reparative processes during retina detachment, the cytologic analysis of subretinal fluid becomes a useful tool in understanding the biological processes that affect visual recovery or impairment after successful retinal detachment surgery.

Experimental disciform serous retinal detachment. II. Autoradiography of photoreceptor protein metabolism.

Protein metabolism of photoreceptor cells was studied by radioautography in disciform serous retinal detachments. The basic sequence of new protein synthesis and distribution within the visual cells was similar to that in control eyes with attached retinas. Compared to retinas with experimental rhegmatogenous detachments, the outer segment renewal process was relatively intact. This may be a consequence of a diffuse protein renewal process being maintained in serous but not in rhegmatogenous detachments.

Experimental Disciform Serous Retinal Detachment

Disciform serous retinal detachments in rabbits are produced by the placement of a selective enzymatic preparation near the level of Bruch membrane. The enzyme solution causes the disruption of collagen and its surrounding ground substance. Light and electron microscopy of combined neurosensory and pigment epithelial detachments demonstrate marked defects and disorganization in the collagen layers of Bruch membrane. Alterations of choroid and pigment epithelium are also present, but these two structures appear relatively intact compared to the changes in Bruch membrane. Experimental serous detachments show good architectural preservation of retina in contrast to experimental rhegmatogenous detachments.

Blood pressure, blood flow and intraocular pressure

The experience of the senior author over the past 18 years in the management of fellow eyes of 3,036 patients with rhegmatogenous detachment is reported. The study group is composed of 2,221 patients with no history of detachment surgery or prophylactic treatment in the functional fellow eye. Of 816 eyes with retinal breaks, lattice degeneration, or retinoschisis—the types of pathology most conducive to detachment—70% were treated with xenon-arc photocoagulation or cryoapplication. Detachment occurred subsequently in 5.4% of the eyes treated with photocoagulation, 2% of the eyes treated with cryoapplications, and 8.2% of the eyes with major pathology that were not treated. Essentially normal fellow eyes with no major pathology and, consequently no treatment, had a subsequent detachment rate of 5.3%. The authors conclude that prophylactic treatment via transconjunctival cryoapplication is safe and effective and recommend treatment of all fellow eyes with lattice degeneration and breaks

Subretinal Fluid Butyrylcholinesterase: 1. Source of the Enzyme and Factors Affecting Its Concentration in Subretinal Fluid From Primary Rhegmatogenous Retinal Detachments

Three sources have been postulated for subretinal fluid (SRF) in primary rhegma­ togenous retinal detachment: vitreous,' de­ generating retina, and plasma transudate from the choriocapillaris.' The theory gen­ erally accepted has been that SRF is liquid vitreous which has percolated through a reti­ nal hole and dissected neural retina off the pigment epithelium.' However, there has been considerable morphologic and biochem­ ical evidence for multiple origins of SRF. Magitot described detached nerve and protoplasmic debris on light micros­ copy of SRF, and concluded that these ele­ ments came from the retina. Manna, Meyer, and Mielnik observed retinal pigment epi­ thelial and neuroretinal cells in the SRF of patients with recent rhegmatogenous detach­ ments, and ghost in fluid from cases of longer duration. Lindner demonstrated the anatomic con­ tinuity of vitreous and SRF through the ret­ inal hole. Proteins which are antigenically specific for vitreous have been identified in SRF. Ascorbic and lactic acids have been found in much higher concentrations in vitreous than in plasma, with SRF levels ly­ ing generally in between. Hyaluronic acid is present in vitreous but absent from plasma. It has always been found in SRF from primary rhegmatogenous detachments, at levels higher or lower than in vitreous.· Paufique showed that in some rhegma­ togenous detachments there appeared to be a leakage of acellular transudate from the cho­ riocapillaris into the subretinal space, com-

Ultrasound in retinal detachment. A preliminary report.

This preliminary report indicates that ultrasound can retrodisplace retinal tissue in certain cases of retinal detachment. Best movement of retinal detachment occurred in those cases exhibiting retinal holes (rhegmatogenous detachments). A 1 megahertz transducer was used. The ultrasonic energy was pulsed. Quantitative measurements of ultrasonic energy delivered from the transducer gave results of 1.95 watts/ sq cm employing a calorimeter. After histopathologic evaluation of 100 rabbit eyes showed no adverse effects on ocular tissue, the transducer was used to treat human retinal detachments. Results indicate that ultrasound may prove to be a prognostic test for successful surgical reattachment of detached retinae. Ultrasound may also prove useful in treating giant retinal breaks, external dissolution of vitreoretinal adhesions, and positioning air bubbles placed within the vitreous cavity.