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Objective: To ascertain if cases of radial keratotomy wound rupture were occurring and whether the globes ruptured through the corneal incisions. Design: Cases of traumatic ruptured globe after incisional corneal refractive surgery were collected from ophthalmologists and from peer-reviewed and other ophthalmic literature. Results: Twenty-eight human eyes (eight previously unreported) are known to have ruptured through refractive corneal incisions in activities of daily living (n=12), assault (n=7), motor vehicle accidents (n=5), and sports (n=4). Two patients died of their injuries. Of the remaining 26 ruptured eyes, eight (31%) recovered 20/40 or better visual acuity. Six eyes (23%) were totally blinded, six (23%) were legally blinded, and six (23%) had best corrected visual acuity of 20/40 to 20/100 despite multiple surgical procedures. Conclusions: As radial keratotomy becomes more popular, the pool of patients who may experience traumatic ruptured globe will grow. Every patient who has had radial keratotomy should be aware that the surgery has weakened the eye(s).

Objective: To review golf-related ocular injuries, which account for 1.5% to 5.6% of all sports injuries. Methods: During 8 years (1986 to 1994), a retrospective review of sports-related trauma was performed at the Medical College of Wisconsin, Milwaukee. Eight blunt ocular injuries (four ruptured globes and four globes without rupture) caused by golf-related activities were identified. The four ruptured globes caused by golf-related trauma accounted for 1.2% of all penetrating injuries and/or ruptured globes and 11.7% of sports-related injuries. Results: A golf ball projectile was the mechanism of injury in six patients, while two patients were struck with a golf club. The four patients with ruptured globes had an initial visual acuity of light perception or worse, and three globes were subsequently enucleated, while one was prephthisic. In the four trauma cases without rupture, surgical intervention was required to achieve anatomic stability, with final visual acuities ranging from 20/25 to 20/40. Conclusions: The incidence of ocular injuries caused by golf-related trauma is low compared with that for other sports-related injuries. Although the prognosis for ruptured globes occurring in this setting remains extremely guarded, blunt trauma without rupture caused by a golfrelated injury is associated with a more favorable visual and anatomic outcome.

• Eighteen eyes with coexisting cataract and vitreoretinal disease underwent combined phacoemulsification, pars plana vitrectomy, and posterior chamber lens implantation. Preoperative vitreoretinal disease included nonclearing vitreous hemorrhage (eight eyes), vitreous hemorrhage and tractional retinal detachment (three eyes), tractional retinal detachment (one eye), epiretinal membranes (three eyes), peripheral uveitis (two eyes), and a retained intraocular metallic foreign body (one eye). Postoperative visual acuity improved in each case; 14 eyes achieved visual acuity between 20/20 and 20/80 during an average postoperative period of 11 months (range, 3 to 39 months). Perioperative complications included an iatrogenic retinal break (one eye) and pupillary block glaucoma (one eye). Four eyes required YAG laser capsulotomy postoperatively. Phacoemulsification did not interfere with corneal clarity, allowed water-tight wound closure during vitrectomy, and preserved the capsular bag, allowing endocapsular fixation of the posterior chamber lens. Combining phacoemulsification, posterior chamber lens implantation, and pars plana vitrectomy allows rapid visual rehabilitation and functional unaided vision in these eyes.

Although the rate of infectious endophthalmitis following penetrating ocular injury is generally less than 10%, certain settings may carry a greater risk of infection. One such setting is penetrating injury resulting from eating utensils contaminated with oral flora. We reviewed six of these injuries. Culture-positive bacterial endophthalmitis developed in four of the six eyes; only one of the eyes retained reading visual acuity (greater than 20/50) and two eyes lost light perception. The potential for infection and limited visual outcome in this series warrants aggressive prophylaxis and treatment. The unexpected isolation of Haemophilus influenzae in two of the four infections suggests that broad-spectrum antibiotic treatment should be considered in all such injuries since less common organisms may be encountered.

• We describe herein a two-stage technique of intraoperative fluid-gas exchange following pars plana vitrectomy. The first stage is a complete fluid-air exchange using an air pump and intraocular linear suction. The air pump then maintains the intraocular pressure at the desired level during adjunctive procedures, such as laser endophotocoagulation. The second stage is an air-gas mixture exchange in which the desired gas, premixed in air to the desired final intraocular concentration, is manually flushed through the eye. This technique allows the attainment of an accurate concentration of intraocular gas if the air-gas mixture exchange is complete. In vitro and in vivo experiments in aphakic human eyes demonstrated that an effectively complete air-gas mixture exchange occurs with a 25-mL flush volume. This result compares favorably with the theoretical prediction derived from a "pharmacolinetic approximation" equation.

A prospective study of 222 consecutive patients undergoing pars plana vitrectomy was done to determine the incidence and mechanisms of postoperative intraocular pressure (IOP) elevation. Within 48 hours of surgery, postoperative IOP increased by at least 5 to 22 mmHg in 136 eyes (61.3%) and to 30 mmHg or more in 79 eyes (35.6%). Presumed mechanisms of open-angle glaucoma included intraocular gas expansion (28.4%), inflammatory trabecular meshwork obstruction (4.5%), silicone oil-related glaucoma (3.6%), and erythroclastic glaucoma (2.2%). Closed-angle mechanisms included pupillary block glaucoma (6.8%) and ciliary body edema (3.6%). Factors which were associated with postvitrectomy pressure elevation included placement of a scleral buckle, either intraoperatively (P = 0.003) or before vitrectomy (P = 0.001), intraoperative scatter endophotocoagulation (P = 0.041), intra-operative lensectomy (P = 0.024), and development of postoperative fibrin membranes (P = 0.038). Surgery was required to lower IOP or relieve pupillary block in 25 eyes (11.3%).

We reviewed 27 consecutive eyes with peripheral uveitis and vitreous base neovascularization that had been treated with cryopexy and followed up for a median of 4.5 years. During the follow-up period, 21 eyes (78%) remained quiescent, whereas five eyes (18%) demonstrated intermittent inflammation, although only one of these eyes progressed to a traction retinal detachment. One eye (4%) eventually atrophied; however, this was believed to be a result of the ongoing uveitis rather than the cryopexy. The treated eyes had an average improvement of three lines in Snellen visual acuity. We found that corticosteroid therapy remains the primary treatment modality for active inflammation, and vitreous base cryopexy should be reserved for those cases which are resistant to corticosteroids, and which demonstrate active neovascularization.

The natural history of peripheral uveitis may eventually lead to indications for vitreous surgery. Over a 7-year period, a consecutive series of 12 eyes in nine patients with peripheral uveitis underwent vitreous surgery. Indications for surgery included persistent dense vitreous inflammation, vitreous hemorrhage, traction retinal detachment (RD), and epiretinal membrane formation. Patients were followed for an average of 22 months. Six eyes (50%) required further surgery after the development of RD, recurrent vitreous hemorrhage, or cataract formation. The preoperative finding most frequently associated with postoperative complications was the presence of active neovascularization of the vitreous base. Final visual acuity ranged from 20/30 to 20/100 showing an average improvement of 5 Snellen lines. Persistent cystoid macular edema significantly limited visual improvement in five patients. Patients undergoing vitreous surgery for management of peripheral uveitis may show a significant degree of visual improvement though multiple operations may be required. Control of active neovascularization is an important factor in limiting postoperative complications and the need for further surgery.

The Silicone Study is a multicenter randomized clinical trial that compares a long-acting gas with silicone oil for the surgical treatment of proliferative vitreoretinopathy (PVR). As part of the study, a topographic classification of PVR has been developed that is based on the characteristic patterns of retinal distortion produced by the contraction of proliferative membranes on the retina or within the vitreous base. This classification is used to document the extent and anatomic distribution of PVR present preoperatively and to help standardize the surgical treatment. Experience has shown that this classification facilitates the identification of these membranes and their systematic dissection, and the authors therefore suggest that it be used to augment the Retina Society classification of PVR.

A 67-year-old white woman had a lesion that clinically, echographically, and angiographically appeared to be consistent with choroidal melanoma. At follow-up examination 2 months later, the lesion had clinically completely resolved. A limited choroidal hemorrhage simulating a choroidal melanoma is postulated.

Subretinal membranes (SRMs) are an important but rarely identified component of proliferative vitreoretinopathy (PRV). In 153 consecutive cases that had vitreoretinal surgery for this condition and were followed for at least 6 months, SRMs were encountered in 72 eyes (47%). In 20 (28%) of the 72 eyes, the SRMs prevented complete retinal reattachment and needed to be removed or excised through one or multiple retinotomies. Intraoperative complications related to the SRMs or their removal included choroidal or retinal hemorrhage in three eyes (15%), subretinal air in three eyes (15%), and unplanned extension of the retinotomies in two eyes (10%). The 20 eyes requiring SRMs removal were followed for a median of 11 months. Retinas were reattached in 13 eyes (65%), although only 4 eyes (20%) had a visual acuity of 5/200 or better. Recognizing SRMs as a component of PVR is important in helping to maximize the anatomic success rate although the effects on visual function are not fully known.

En bloc excision is a technique in which fibrovascular diabetic membranes and the posterior hyaloid are separated from the retina as a single unit. In a consecutive series of 69 eyes with diabetic traction retinal detachment treated with this technique, initial retinal reattachment was accomplished in 100% (69/69) of the eyes. With a minimum of 6 months' follow-up, the retina remained completely attached in 83% (57/69) of eyes, while the macula was attached in 88% (61/69) of eyes. Final visual acuity was 5/200 or better in 71% (49/69) of eyes. While current surgical techniques allow a high rate of anatomic success in the repair of diabetic traction retinal detachment, visual results remain limited by irreversible alterations in retinal function.

Canthaxanthine retinopathy in humans is a retinal crystalline deposition associated with ingestion of canthaxanthine, an over-the-counter oral tanning agent. In this study cats were fed doses of canthaxanthine varying from 2 mg/kg/day (an equivalent standard human dose) to 16 mg/kg/day for up to six months. Indirect opthalmoscopy showed progressive development of an orange sheen in the retina overlying the tapetum lucidum without evidence of crystal formation. Electroretinograms performed at one and two months showed no significant change from baseline examination. On light and transmission electron microscopic examination, the retinal pigment epithelium of the experimental animals showed an increase in cell height and a regional vacuolization due to an enlargement and disruption of some phagolysosomes and the development of cytoplasmic spaces. These observations suggest that further studies should be conducted on humans who ingest canthaxanthine to assess structural and functional alterations, especially in the pigment epithelium.

We used a high-energy argon blue-green laser (15-W maximum power output) to create full-thickness sclerostomies from the region of the anterior chamber angle to the subconjunctival space in pigmented rabbits using an ab interno approach. One to four laser pulses delivered through a 300-micron noncontact fiberoptic probe produced patent sclerostomies in all 20 eyes treated using 0.1-second pulse duration and 5 to 14 W of power. No intraoperative complications were encountered. Intraocular pressure, measured in 12 animals, decreased an average of 12 mm Hg in the treated eye relative to the fellow eye on the first postoperative day. The drop in intraocular pressure was associated with formation of a functioning filtration bleb. Intraocular pressure returned to preoperative levels in ten of 12 (83%) of the animals by the fourth postoperative day, and there was an associated flattening of the filtration bleb. Histologic and radioautographic analysis indicated that the effect of the laser was focal. Tissue damage and cellular proliferative response were limited to within approximately 200 micron of the wound margin.

• Traumatic retinal incarceration into a scleral wound may prevent successful surgical rehabilitation of eyes with severe posterior segment injury. We managed 15 consecutive eyes with traumatic retinal incarceration and associated retinal detachment with vitrectomy techniques. We based our approach on the anteroposterior location of the incarceration site and the amount of retina incarcerated into the wound. Despite successful anatomic reattachment in six of seven eyes with retinal incarceration posterior to the vortex vein ampullae, only two of seven eyes achieved visual acuity of 5/200 or better. In eyes with more peripheral retinal incarceration, anatomic reattachment was achieved in five of eight eyes and visual acuity of 5/200 or better was achieved in four eyes. Overall, a visual acuity of 5/200 or better was achieved in six (40%) of 15 eyes with a minimum follow-up of six months.

• Acute retinal necrosis (ARN) is a syndrome of fulminant necrotizing vasoocclusive retinitis associated with a high incidence of retinal detachment due to retinal breaks and vitreous traction. We performed argon or krypton laser photocoagulation to demarcate areas of active retinitis as prophylaxis against retinal detachment in five patients with ARN. Patients were concomitantly treated with antiviral agents, systemic steroids, and antiplatelet therapy. One patient required multiple additional treatments as retinal necrosis progressed. The retinas remained attached in all five patients over a mean follow-up period of 15 months. By creating a chorioretinal adhesion in areas of potential retinal break formation, laser photocoagulation may be an effective prophylaxis against retinal detachment in ARN.

Hyperthermia has been combined with conventional radiation methods to achieve enhanced tumor destruction. We combined iodine 125 seeds with ferromagnetic thermoseeds in a single plaque to simultaneously deliver radiation and heat in a rabbit model of choroidal melanoma. Initially, six ferromagnetic thermoseeds were placed in parallel on a 14-mm episcleral plaque. The plaques were placed on normal rabbit eyes and on eyes containing transvitreally implanted choroidal melanoma. The heating response was assessed in both normal and tumor-containing eyes. Rigid copper-constantan and flexible Baily thermocouples were used to monitor temperature responses. The animals were subjected to an electromagnetic field of 100 kHz, with power of 1100 to 1500 W. The thermoseeds autoregulated at 48.2 degrees C. Scleral temperatures stabilized at 45.8 degrees C +/- 0.4 degrees C (SD), while temperatures at the base of the tumor stabilized at 43.6 degrees C +/- 0.1 degrees C. Ferromagnetic thermoseeds were then combined with iodine 125 seeds. Similar temperature responses were recorded, and autoradiographic findings confirmed a uniform radiation distribution. Varying the amount or type of ferromagnetic material in the thermoseeds allows the delivery of heat at virtually any temperature. Ferromagnetic hyperthermia may provide a more simplified approach over currently available methods of heat delivery.

• Visualization of the position of an episcleral plaque in relation to the underlying choroidal melanoma during the early radiation treatment period reconfirms accurate plaque location and may help assure optimal treatment. We used high-resolution B-scan echography to confirm the position of the episcleral plaque in 16 consecutive cases of choroidal melanoma. The technique is most useful for well-defined tumors as small as 3 mm in height whose anterior border does not extend beyond the ora serrata.

The Silicone Study is a multicentered, randomized surgical trial designed to compare the tamponade effectiveness of silicone oil versus longacting gas in the treatment of proliferative vitreoretinopathy (PVR) by vitrectomy and associated techniques. Fundus photographs are taken to provide documentation of the anatomic status of eyes proposed for entry and are graded at an independent Reading Center. This article describes the protocol for photographic documentation of PVR as a continuum of increasing pathology, in which the pathology may only be present in the anterior retina, and the retina is usually highly elevated. In a validity and reliability study, agreement between photographic and clinical observation within one step was obtained for 88% of the eyes; intra- and inter-observer agreement within one step was 85 and 80%, respectively. Differences between the surgeon's grade and the Reading Center's were caused about equally by disagreement regarding extent of fixed folds and width of the funnel. Rarely did peripheral folds not visible in the photographs appear to be the sole explanation of the disagreement. Differences among readers were concerned mainly with differentiation of true full-thickness fixed folds from folds due to simple redundancy of the detached retina. These results demonstrate that complicated retinal detachment (RD) can be photographically documented and independently assessed.

Retinal detachment (RD) occurs in more than 50% of eyes with acute retinal necrosis (ARN) and is the leading cause of visual loss in this syndrome. In order to decrease the incidence of RD in ARN, the authors treated 12 eyes of 10 patients with prophylactic laser photocoagulation. Retinal detachment occurred in two eyes (17%). Over the same time period, seven eyes with ARN did not receive prophylactic laser treatment, most often because of dense vitreous debris, with a 67% rate of RD. Prophylactic photocoagulation treatment should be considered in the management of patients with ARN.

Of 105 eyes with ocular injuries involving retained intraocular foreign bodies, 63 (60%) had a final visual acuity of 20/40 or better; 20 (19%) were 20/50 to 5/200; and 15 (14%) were worse than 5/200. Six eyes (6%) were enucleated. The extent of visual recovery was limited in selected cases by the characteristics of the initial injury. Multivariate analysis was used to identify prognostic factors. Predictive of a good visual outcome (greater than or equal to 20/40) were: (1) initial visual acuity better than 20/40 and (2) the need for only one or two operations in the treatment of the injury. Predictive of a poor visual outcome (less than 5/200) were: (1) initial visual acuity worse than 5/200 and (2) a wound 4 mm or longer in length, independent of wound location. The visual outcome in this series of patients was compared with other large series of intraocular foreign bodies reported before the development of vitreous microsurgical techniques. The percentage of patients with a visual outcome of 20/40 or better has remained the same, whereas the incidence of enucleation has diminished.

• We developed a new illuminated disposable retinal pick system for use in vitreoretinal surgery. These instruments facilitate bimanual dissection of proliferative tissue while allowing ocular endoillumination. We have found these instruments to be helpful in the management of complicated retinal detachment due to proliferative diabetic retinopathy or proliferative vitreoretinopathy.

We studied the use of a 15-W argon blue-green laser in the treatment of choroidal melanoma in a rabbit model. Greene melanoma cells were used to produce 2- to 4-mm thick tumors posteriorly in the suprachoroidal space in pigmented rabbits. Endophotocoagulation delivered through a 600-micron fiberoptic probe was performed to ablate the tumor tissue and a surrounding margin of normal tissue. A vitreous cutter was used simultaneously to remove liberated necrotic debris. The effect of the laser on tumor and normal ocular tissue was evaluated by light microscopy and the extent of the proliferative response by tritiated thymidine radioautography. Application of 100 to 400 pulses of laser energy using treatment parameters of 12 to 14 W of power and 0.1-s pulses resulted in complete ablation of melanoma tissue, overlying retina, and choroid. There was no substantial intraoperative or postoperative hemorrhage. Material liberated during the laser treatment was found to be nonviable. The effect of the laser on tissue appeared localized to within approximately 1.25 mm of the margin of the central lesion. The high-energy argon laser seems to offer a means of effectively ablating melanoma tissue via an internal resection approach.

A high-powered argon blue-green laser coupled to a 300-microns quartz fiberoptic probe was used to create an ab interno sclerostomy in a patient undergoing enucleation for a blind painful eye. Despite the presence of diffuse rubeosis, 360 degrees peripheral anterior synechiae, and superior conjunctival scarring, it was possible to create a full-thickness defect from the anterior chamber angle to the subconjunctival space without operative complications. Six laser applications were required using 8 W of power per pulse and 0.1-second pulse duration. The eye was enucleated immediately after the laser procedure, prepared for light microscopy, and sectioned serially. Histologic analysis demonstrated a patent fistula approximately 300 microns in diameter with sharp wound margins. Tissue damage was localized to within 150 microns of the sclerostomy. The overlying conjunctiva was intact.