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Three patients with uveitis and dense pupillary membranes, total synechial closure of the angle, and low or normal pressure, underwent membranectomy and anterior vitrectomy via a limbal approach using scissors and a vitrectomy instrument. Postoperatively all regained useful vision that has been maintained for over two years despite the persistence of angle closure in all cases and severe hypotony in two.
We developed a 20-gauge combination illumination-irrigation probe for use in pars plana vitrectomy. This instrument makes the vitrectomy procedure less traumatic and technically easier.
Of the results evaluated in 17 patients who had vitrectomy for aphakic vitreocorneal touch associated with corneal edema, nine patients had satisfactory results. Factors associated with a favorable outcome were as follows: (1) early vitrectomy; (2) previtrectomy visual acuity better than 6/120 (20/400); (3) uncomplicated cataract operation and postoperative course, and (4) broken rather than intact hyaloid face. Postoperative cystoid macular edema contributed to decreased visual acuity in eight of 12 patients.
We have developed a series of temporary keratoprostheses that permit closed pars plana vitrectomy in eyes with abnormal corneas. These devices are placed into a trephined opening in the cornea, and provide a clear, stable view of the intraocular contents. Immediately after vitrectomy, the keratoprosthesis is replaced with a corneal graft. We have used this technique successfully in four eyes with opaque or severely traumatized corneas.
The surgical results for 248 eyes that underwent vitrectomy for diabetic vitreous hemorrhage showed that at the final examinations, 194 (78%) had improved visual acuities, 43 (17%) had worse visual acuities, and 11 (4%) were unchanged. Of the 248 eyes, 60 (24%) had final visual acuities of 20/40 or better, 128 eyes (52%) had final visual acuities of 20/50 to 20/800, and 60 (24%) had final visual acuities worse than 20/800. Eyes with preoperative iris neovascularization had a substantially worse visual result than eyes without this complication. Eyes in which the lenses were removed during vitrectomy also had worse visual results, primarily because they had a higher cumulative incidence of postoperative iris neovascularization and neovascular glaucoma.
We analyzed the surgical results for 197 eyes that underwent vitrectomy for diabetic traction detachment of the macula. The retina was successfully reattached in 130 of the 197 cases (66%), although the final level of vision depended on the amount of permanent macular damage from the previous detachment and on the effects of the retinal vascular disease. At the final examinations, 112 eyes (57%) had improved visual acuities, 68 eyes (35%) were worse, and 17 eyes (9%) were unchanged. Thirteen eyes (7%) had final visual acuities of 20/40 or better, 103 eyes (52%) had final visual acuities of 20/50 to 20/800, and 81 eyes (41%) 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 vitreous hemorrhage (P less than .01) and the absence of preoperative scatter retinal photocoagulation (P less than .01). Additionally, two surgical factors, lens removal and the creation of iatrogenic retinal breaks, were associated with a poorer visual prognosis (P less than .002 and P less than .01, respectively). The group of eyes that underwent lens removal during vitrectomy also had a significantly higher incidence of postoperative iris neovascularization compared to eyes in which the lenses were not removed (P less than .05).
Five patients with nonclearing vitreous hemorrhage associated with subarachnoid or subdural hemorrhages (Terson's syndrome) underwent pars plana vitrectomy. All six eyes of the five patients had postoperatively improved visual acuity and visual function. We recommend treating this rare syndrome with vitrectomy after careful preoperative ophthalmologic examination and a minimum observation period of six months to one year.
In a series of 112 consecutive patients who underwent vitrectomy because of severe penetrating ocular trauma, good visual recovery (6/12 [20/40] or better) was achieved in 15 of 23 patients (65%) who underwent surgery within 72 hours of the injury (Group 1), in seven of 14 patients (50%) who underwent surgery three to ten days after injury (Group 2), in eight of 22 patients (36%) who underwent surgery ten to 14 days after injury (Group 3), in two of five patients (40%) who underwent surgery 14 to 30 days after injury (Group 4A), and in 17 of 48 patients (35%) who underwent surgery more than 40 days after injury (Group 4B). Functional vision (6/12 [20/40] to counting fingers) was achieved in three of 23 patients (13%) in Group I, five of 14 patients (36%) in Group 2, six of 22 patients (27%) in Group 3, two of five patients (40%) in Group 4A, and in 22 of 48 patients (46%) in Group 4B. These data indicated that definitive early surgical intervention, including vitrectomy, should be considered as part of the primary repair or performed within 72 hours of the injury. Early surgery provides a statistical better prognosis for good visual recovery than a delay of three to 14 days or longer.
Purpose: The Rayleigh color matches were measured to investigate the optical density in the cone photopigment of the central retina in patients with macular holes that had closed after vitrectomy.Methods: The Rayleigh equation was measured with the IF-2 anomaloscope in 7 patients with macular holes in one eye, that had closed after vitrectomy and gained an improvement in visual acuity of 0.5 or better. Reductions in the pigment optical density of cone photoreceptors of the opposite eyes were estimated with Rayleigh equations obtained in this experiment.Result: The Rayleigh equations of the affected eyes were shifted toward protanomalous setting compared with that of the opposite eyes. The optical densities of cone photoreceptors of the affected eyes were lower than those in the opposite eyes, even in patients with visual acuity of 1.0 or better.Conclusion: These findings suggest that the recovery of the visual acuity may precede that of the optical density in cone photopigment of central retina. The Rayleigh equation is more sensitive than visual acuity for evaluating visual function after vitrectomy for macular holes.
Vitreous surgery techniques are useful in the management of selected retinal detachments with an otherwise poor prognosis. Vitrectomy methods can be used to remove intraocular opacities; cut vitreous sheets causing vitreo-retinal traction and separate epiretinal membranes covering or distorting the retina; provide a fluid space to aid in creation of a scleral buckle or use of an intravitreal gas bubble; perform other intraocular procedures, including transvitreal treatment of retinal breaks, transvitreal removal of subretinal fluid, and intraocular fluid-gas exchange. These surgical capabilities can be combined with conventional retinal reattachment methods to treat selected types of retinal detachment. The surgical techniques, indications for surgery, and role of vitrectomy methods in the current management of retinal detachment are reviewed.
One hundred and seventy-four instances of diabetic traction retinal detachment in which the patient underwent closed vitrectomy during the period of January 1970 to December 1978 and had adequate follow-up ranging from six months to five years are reported. As a rule, eyes with vision better than 20/200, or with inaccurate light projection, or with no response to electrophysiologic tests were excluded. The surgical technique avoided stripping of vitreous membranes. Closed vitrectomy was combined with scleral buckling in eyes with retinal breaks, and with scleral resection in eyes with incomplete section of traction membranes. Anatomic improvement was noted in 75.3% of the eyes; vision improved in 64.9% of the eyes; new or recurrent vitreous hemorrhage was observed in 43.1%; corneal decompensation in 51.8%, rubeosis iridis in 23.0%, phthisis bulbi in 9.2%, iatrogenic retinal break in 8.6%, postoperative rhegmatogenous retinal detachment in 5.2%, and iatrogenic cataract in 4.6%.
The influence of total vitrectomy on the success rate of filtration surgery was investigated, with 47 operations (6 reoperations) being performed on 41 patients. At six months postoperatively, successful control (IOP less than 21 mm Hg) was achieved in 32 of 41 patients (78%). Twenty-four patients had filtration blebs present. Total vitrectomy favorably influences the result of filtration surgery. However, the morbidity rate (two retinal detachments and two cases of cystoid macular edema) is higher than in standard filtration procedures.
A single or double plate Molteno Implant may control IOP in otherwise desperate cases. Fibrosis of the filtration bleb will lead to failure. We report about 4 patients (age 12 to 77 years--3 neovascular glaucoma, 1 with postinflammatory goniosynechia) who had good IOP after the implantation of a Molteno device. 10 to 26 weeks (mean 18.25) after glaucoma surgery we performed a pars plana vitrectomy because of different reasons: proliferative diabetic retinopathy, proliferative retinopathy due to central venous occlusion, ciliovitreal block mechanism, PVR D3. One aphakic eye was treated with silicone oil and an encircling band. 19 to 30 weeks after posterior segment surgery (mean 24.5) IOP remained controlled. We describe the technique of pars plana approach and putting an encircling band without destroying the preformed filtration bleb. Encircling techniques, pars plana vitrectomy and silicone oil in aphacic eyes seem to bee possible without loss of the filtration effect of the Molteno operation.
Report on 96 cases in which pars plana vitrectomy was performed because of intravitreal hemorrhage. In 25 patients vitrectomy had to be performed bilaterally. Postoperative follow-up ranged from 3 months to 2 1/2 years. An improvement of visual acuity lasting at least 3 months was achieved in 58% of the cases. In 31% central vision remained unchanged, and in 11% cases the postoperative vision was decreased. Secondary hemorrhage necessitated a repetition of the intervention in 16 eyes.
Of 63 eyes on which vitrectomy was performed with a follow-up of at least six months 34 had an ERG with a b-wave of 50 muV or more preoperatively. Twenty-nine eyes had a b-wave of less than 50 muV. Twenty-six (76%) with an ERG > 50 muV, but only five eyes with an ERG < 50 muV had useful vision postoperatively. Of the eyes with an ERG <50 muV and without useful vision post-operatively, 75% were found intraoperatively to have a total retinal detachment. From these results it is concluded that the preoperative ERG findings are of great value for evaluating the prognosis of a vitrectomy.
The authors illustrate by means of a film the surgical difficulties and dangers involved in a vitrectomy procedure completed by a peeling of preretinal membranes. Taking a case of proliferative diabetic retinopathy, they demonstrate and justify their surgical indications for vitrectomy in diabetics.
Asteroid hyalosis is a common, usually asymptomatic, benign vitreous disease affecting older individuals. A case report of an aphakic patient who developed anterior segment complications with no visualization of the fundus is presented. A pars plana anterior and posterior vitrectomy was performed using the Ocutome system. An excellent technical result with moderate restoration of vision was achieved. Preoperative evaluation with ultrasound was helpful. Pathology confirmed the diagnosis of calcium-containing lipids. Other indications for vitrectomy for asteroid hyalosis include retinal detachments in which the tear cannot be seen and diabetic retinopathy in which laser cannot be performed. Differential diagnosis includes synchysis scintillans, which is usually bilateral and seen in younger individuals after severe ocular inflammation, trauma, or hemorrhage.
The author presents a simple surgical device enabling ophthalmic surgeons to manage vitreous loss in cataract surgery or perforating injuries in a safer and simpler way and with less postoperative complications. The instrument set-up has the following specifications: perfectly cutting vitrectomy microinstrument, mechanical device for repeated use of the cutting edge of the trephine. The instrument set is ready for use in less than 1 min. The same instrument device can be used for several other purposes in anterior and posterior segment surgery, especially for delicate problems in pars plana vitrectomy.