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We used a modification of lens removal by phacofragmentation in conjunction with posterior vitrectomy without any serious complications in over 200 procedures. This modification allowed removal of hardened nuclear sclerotic lenses and reduced the time required for lens removal.
We enucleated an eye of a 39-year-old white man four weeks after partial pars plana vitrectomy was carried out for removal of an amagnetic foreign body which failed. Vitreous clouding complicated the perforating injury. Histological findings included massive ingrowth of fibrous tissue into the vitreous space and along preretinal planes, total retinal detachment with degenerations, and localized proliferations of the pigmentary epithelium. All proliferations originated at the site of the sclerotomy incision.
The technique of removal of blood from the retinal surface in pars plana vitrectomy using a blunt-tipped needle open to the atmosphere has two disadvantages: uncontrolled suction force at the tip of the needle, and a drop in intraocular pressure to zero when the needle is vented to the atmosphere. Modification of the procedure can eliminate these problems. By connecting the blunt-tipped needle to a bag of intravenous fluid, the suction force of the needle can be controlled; and by elevating both the bag connected to the infusion line and that connected to the suction needle, the intraocular pressure can be increased and the problem of intraocular bleeding minimized or eliminated.
A 14-year-old boy, an 11-year-old girl, and a 3-year-old girl with Wagner's vitreoretinal degeneration had multiple retinal detachments. Surgical repair by means of conventional scleral buckling and encircling techniques was unsuccessful. However, after vitrectomy, their retinas remained flat.
I designed a new type of contact lens for vitrectomy that consists of an outer scleral part and an inner rotatable cylindrical piece with a prismatic anterior surface.
A series of 75 eyes underwent pars plana vitrectomy for progressive diabetic traction retinal detachment of the macula. In all cases, the media was sufficiently clear to allow preoperative macular examination. The overall visual improvement was higher in phakic eyes (80%) than aphakic eyes (72%) and the rate of neovascular glaucoma was less in phakic eyes. The difference was not statistically significant, however. The final visual acuity corresponded to the degree of preoperative visual deterioration. Thus, surgery during the rapidly evolving proliferative and retracting process did not adversely affect the visual success rate when compared to previous reports on longstanding vitreous hemorrhage.
Eight patients with severe traumatic hyphemas underwent clot evacuation with vitrectomy instrumentation. The patients were followed up for periods of one to four years. No significant intraoperative complications were noted, but one eye developed a postoperative flat anterior chamber and another developed multiple staphylomas with uncontrolled glaucoma, leading to the eventual enucleation. Seven of the eight operated eyes achieved intraocular pressure control in the early postoperative period, and this control was sustained throughout the course of follow-up without antiglaucomatous medication. These same seven eyes had final visual acuities of 6/12 (20/40) or better.
We devised an adjustable length infusion needle for Ocutome vitrectomy. Visualization of the tip of the infusion terminal is not necessary and the risk of infusion into the uvea is eliminated.
Four infants and one child with retinal detachments from cicatricial retrolental fibroplasia involving traction judged too severe to be relieved by scleral buckling alone underwent lensectomy and vitrectomy. Three retinas were successfully reattached. Because of the incomplete development of the pars plana in infants and the manner in which peripheral retina is pulled anteriorly to a position near or in contact with the posterior lens capsule, entry through the pars plana can create iatrogenic tears in the peripheral retina or introduction of irrigation fluid under the retina. Our experience has shown that a small contact lens makes it possible to work in the posterior vitreous cavity through the limbal approach in these infants. The circumferential traction produced by the ring of fibrovascular proliferation behind the lens can be relieved and tractional bands running forward from the posterior pole can be cut. Fibrovascular proliferative tissue lying on the posterior pole, however, proved resistant to membrane peeling or dissection, and its severity seemed to determine the success or failure of the surgery.
In 14 eyes undergoing a pars plana filtration procedure combined with pars plana lensectomy and vitrectomy, the most common complication was a severe sterile fibrinous vitritis. However, after a mean follow-up period of 6.3 months, intraocular pressure was controlled in five eyes (36%) after the procedure alone, in two (14%) after subsequent medical therapy, and in three (21%) after subsequent cyclocryotherapy. Preoperative visual acuity was maintained or improved in nine of the eyes (64%), whereas four eyes (28%) had no light perception.
The surgical results for 107 eyes that underwent vitrectomy for diabetic rhegmatogenous retinal detachment showed that the rhegmatogenous component of the detachment was successfully treated in 79 eyes (74%), although in 11 of the 79 eyes (14%) traction detachment of the macula persisted. At the final examinations, 57 eyes (53%) had improved visual acuities, 44 (41%) had worse visual acuities, and six (6%) were unchanged. Eleven eyes (10%) had final visual acuities of 20/40 or better, 48 eyes (45%) had final visual acuities of 20/50 to 20/800, and 48 eyes (45%) had final visual acuities worse than 20/800. Two preoperative factors were associated with a worse prognosis for achieving a final visual acuity of 20/800 or better: preoperative iris neovascularization (P less than .01) and preoperative detachment of the macula (P less than .05).
Fluorouracil effectively inhibits epiretinal membrane formation and traction retinal detachment after vitrectomy surgery. When 0.5 mg of fluorouracil was administered intraocularly every 24 hours for seven days, traction retinal detachment two weeks after the intraocular injection of 200,000 cultured retinal pigment epithelial cells occurred in 12 of 12 control eyes but in only six of 14 eyes treated with fluorouracil (P less than .001). Four weeks after cell injection, eight of 12 eyes treated with fluorouracil had traction retinal detachments whereas 12 of 12 control eyes did (P less than .001). The height of the traction retinal detachment four weeks after intraocular injection of 200,000 cultured retinal pigment epithelial cells was reduced 50% in eyes treated with 0.5 mg of fluorouracil every 24 hours for seven days compared to control eyes (P less than .001). When the number of injected retinal pigment epithelial cells was increased to 400,000 cells and 1.25 mg of fluorouracil was administered intraocularly every 24 hours for seven days, traction retinal detachment two weeks after injection occurred in 15 of 15 eyes in the control group but in none of ten eyes in the treated group. Four weeks after cell injection, eight of eight eyes in the control group and five of five eyes in the fluorouracil-treated group had detachments and the mean height of the detachments in the two groups was equal. Autoradiography of the epiretinal membranes in eyes injected with 200,000 cultured retinal pigment epithelial cells and labeled for two hours with tritiated thymidine showed that 0.8% of the epiretinal cell nuclei were labeled two weeks after cell injection but that no labeled cells were present in the fluorouracil-treated eyes. Tritiated thymidine labeling of epiretinal cells in the fluorouracil-treated eyes was first noted three weeks after the cell injection. The presence of tritiated thymidine labeling in the fluorouracil-treated eyes correlated with an increase in the number of epiretinal cells and an increase in the incidence of traction retinal detachment.
The retinal and corneal toxicity of fluorouracil in the rabbit eye after lensectomy and vitrectomy depended on both the dosage and the frequency of intraocular injection and was reversible at certain dosages. All eyes in Group 1 (1.25 mg of fluorouracil every 12 hours for four days and then every 24 hours for three days) had opaque corneas by three days; these did not clear for four weeks. Histologic studies showed loss of photoreceptor outer segments and loss of ribosomes in all the retinal cells examined. The electroretinographic b-wave decreased to 0% of the baseline value (no b-wave), and did not recover after three weeks. In Group 2 eyes (1.25 mg of fluorouracil every 24 hours for seven days), corneal opacification increased to a maximum after two weeks and gradually decreased by four weeks. The electroretinographic b-wave diminished to 9.6% of the baseline value at two weeks but later recovered to 62.5% of the baseline value at three weeks. Histologic studies showed loss of photoreceptor outer segments and ribosomes at nine days; both returned to near normal after five weeks. Clinical, electrophysiologic, and histologic studies showed no toxicity in Group 3 eyes (0.5 mg of fluorouracil every 24 hours for seven days). This dosage of fluorouracil exerts a significant antiproliferative effect on injected retinal pigment epithelial cells and is well tolerated by the rabbit eye.
Five eyes of five patients with opaque corneas underwent penetrating keratoplasty after pars plana vitrectomy. In each case, the Landers-Foulks temporary keratoprosthesis provided visualization of the vitreous cavity and retina, allowed successful removal of hemorrhagic vitreous, and permitted retinal reattachment. Corneal grafts remained clear in two eyes; three grafts developed stromal edema. Useful postoperative vision was achieved in two eyes. However, proliferative vitreoretinopathy, postoperative hypotony, atrophia bulbi, and corneal edema resulted in poor vision in three eyes.
A long-term follow-up study of 130 eyes that had had initially successful vitrectomies for complications of proliferative diabetic retinopathy showed that only ten (8%) eyes had significant worsening of visual acuity at final examination (18 to 68 months after surgery), compared to the best visual acuity recorded during the first six months after surgery. Active flat retinal neovascularization was present at final examination in only three eyes (2%), and in no case did elevated fibrovascular proliferation occur. The type and incidence of important complications during the early and later postoperative periods indicated a low rate of late complications.
We used closed vitrectomy techniques to remove formed vitreous from the anterior chamber in a consecutive series of 38 eyes with the vitreous touch syndrome. The visual results in these cases were related to the severity of corneal edema and the visual acuity recorded preoperatively. Most patients with preoperative visual acuities of 6/15 (20/50) or better demonstrated a clearing of corneal edema and an improvement in vision. Of eyes achieving visual acuities of 6/12 (20/40) or better within six weeks of vitreous surgery, 14 (74%) maintained this level during follow-up. No eyes with preoperative visual acuities of 6/90 (20/300) or worse achieved good results. The incidence of complications of vitreous surgery was acceptable, although cystoid macular edema developed postoperatively in at least 10%. Closed virectomy techniques provide a safe and effective means of treating the vitreous touch syndrome when corneal edema is localized.
We successfully treated six patients with culture-proven acute bacterial endophthalmitis by a combination of emergency pars plana vitrectomy and the instillation of intravitreal antibiotics. All six patients regained satisfactory vision.
Formation of thick and occasionally dense retropseudophakos membranes and rapid fibrosis of the posterior capsule is a complication that adversely affects the outcome of intraocular lens implantation. We have observed this condition in 17 patients, most of whom presented with traumatic and congenital cataracts. It appears to occur more frequently in young individuals and children. Simple capsulotomy, by the limbal approach or with the YAG laser, does not reliably eliminate the membranes. We have used vitrectomy and scissors dissection through the pars plana to achieve good anatomical results. Postoperative visual acuity has been satisfactory, except in amblyopic eyes related to congenital cataracts.