A comparison of the effects of topical cyclosporine and topical steroid on rabbit corneal allograft rejection.

A comparison was made of the effects of topically applied cyclosporine, and topically applied prednisolone acetate, on the prolongation of corneal allograft survival in a recently developed prevascularized rabbit eye model. Animals were treated four times daily for 28 days postgrafting. Both drugs prolonged graft survival when compared with placebo or no treatment but the corticosteroid was significantly more effective than cyclosporine. Furthermore, anterior segment inflammation and graft vascularization were considerably less marked in animals treated with steroid. No cyclosporine could be detected by radioimmunoassay in anterior chamber fluid removed by paracentesis from grafted animals treated with cyclosporine, suggesting poor absorption of the drug across the cornea.

Promotion of graft survival by photothrombotic occlusion of corneal neovascularization.

Corneal neovascularization may reduce the success of penetrating keratoplasty. Photothrombosis using intravenous rose bengal and argon laser irradiation has shown promise for occluding corneal vessels. It is therefore conceivable that photothrombosis can improve the graft survival in vascularized corneas. Using intracorneal 7-0 silk sutures as the stimuli, corneal neovascularization was induced in 1 eye each of 19 New Zealand white rabbits. Eleven eyes received photothrombosis. Successful occlusion with subsequent regression was verified by corneal fluorescein angiography. Three were assigned for observation. Six of 8 eyes receiving grafts from an outbred rabbit donor after photothrombosis remained clear during 6.5 to 18.5 weeks of follow-up, while vascularization and opacity occurred in 7 of 8 control eyes without photothrombosis. These results indicate that prior photothrombotic occlusion of corneal vessels can significantly improve graft survival in this experimental model and may have clinical applications.

Chronic postoperative endophthalmitis associated with Propionibacterium acnes.

We present two cases of Propionibacterium acnes endophthalmitis that confirm the association of this organism with a delayed onset and chronic and indolent intraocular inflammation following extracapsular cataract extraction with posterior chamber intraocular lens implantation. The clinical, microbiologic, and histopathologic features of these cases suggest that the organism can be sequestered in the capsular bag, which may make this entity difficult to diagnose. We conclude that complete capsulectomy may be required if inflammation persists after conventional treatment for endophthalmitis, which may include pars plana vitrectomy, partial capsulectomy, and antibiotic therapy. Sterile postoperative uveitis is a diagnosis of exclusion. We stress the importance of appropriate microbiologic investigation in all cases of postsurgical inflammation, even if the onset is delayed until several months after surgery.

Chronic postoperative endophthalmitis associated with Actinomyces species.

Actinomyces species, gram-positive, non-spore-forming anaerobic bacilli were isolated from intraocular fluid obtained from four otherwise healthy patients with a delayed onset of postoperative endophthalmitis. One patient had a mixed anaerobic infection with recovery of both Actinomyces israelii and Propionibacterium acnes. In all four patients, early postoperative visual acuity was good but was eventually markedly reduced by intraocular inflammation that was first observed between 21 days and 4 months following uneventful extracapsular cataract extraction and posterior chamber intraocular lens implantation. Inflammation was characterized by anterior segment and vitreous cellular debris in all cases. All eyes responded to therapy that included intraocular, topical, and systemic antibiotics as well as pars plana vitrectomy and partial iridectomy. These cases further illustrate the need for microbiologic investigation, including anaerobic cultures, in all cases of chronic postoperative inflammation following extracapsular cataract extraction, regardless of the time of onset.

Photogrammetric analysis of corneal trephination.

We used a high-magnification shadow photogrammetric system to evaluate corneal buttons trephined from human donor globes. Whole eyes were trephined with one of five instruments: nonguarded blades held by hand or placed on a handle, Barraquer-Mateus motorized trephine, Hessberg-Barron suction trephine, or Hanna microkeratotrephine. Corneoscleral buttons were punched with one of three punches: Cottingham, Katena Lieberman guillotine, or a modified Lieberman guillotine with an increased impact force (BPEI 2). The precision (how closely buttons approximated the trephine diameter), accuracy (repeatability), acircularity (deviation from roundness), and straightness (verticality of edges) of cut were calculated from the diameter and edge profile angle measurements of buttons cut by the different instruments. These results were statistically compared. The Hanna microkeratotrephine instrument had the greatest precision and accuracy, least acircularity, and straightest edges. Of the corneal punches evaluated, the Cottingham instrument had the greatest precision; however, the BPEI 2 punch cut with the greatest accuracy and the straightest edges.

Elevated corneal epithelial lines in Acanthamoeba keratitis.

Elevated corneal epithelial lines are another clinical sign in Acanthamoeba corneal infection. In this report, one patient wore extended wear soft contact lenses, and another wore daily wear soft contact lenses. Both patients used distilled water and salt tablets in their lens care. Histopathologic examination of these lines revealed trophozoites and cysts. In one of the patients following penetrating keratoplasty, Acanthamoeba castellani and Acanthamoeba polyphaga were cultured by impression cytology of an epithelial line, as well as from the bulbar and tarsal conjunctiva. In the other patient who did not undergo penetrating keratoplasty, these lines appeared in the cornea one month after initial symptoms.

Gonococcal keratoconjunctivitis.

Gonococcal keratoconjunctivitis is a potentially devastating infection, because Neisseria gonorrhoeae can cause a rapid, severe, ulcerative keratitis resulting in visual loss. The therapeutic decision making process is complicated by the necessity for prompt, effective parenteral therapy, frequent coinfection with other sexually transmitted diseases, and emergence of antibiotic resistance. Because of the evolving problem of antibiotic resistance and the need for cost containment, the current recommendations of hospitalization for intravenous penicillin may need to be modified. The third generation cephalosporin, ceftriaxone, has properties that suggest it may be the best available antimicrobial agent as a single-dose treatment of gonococcal conjunctivitis. Spectinomycin may be a useful alternative in the penicillin-allergic adult patient.

Minimum bactericidal concentrations of Propionibacterium acnes isolates from cases of chronic endophthalmitis.

Six isolates of Propionibacterium acnes recovered from cases of chronic infectious endophthalmitis following extracapsular cataract extraction were tested for antibiotic susceptibility. All isolates were susceptible to penicillin, cefazolin, and vancomycin with a macrobroth dilution method. Minimum bactericidal concentrations testing at 72 h revealed that six of six isolates were killed by < or = 1.0 micrograms of vancomycin/ml, one of six isolates by < or = 1.0 micrograms of penicillin/ml, and zero of six isolates by < or = 1.0 micrograms cefazolin/ml.

Treatment of gonococcal conjunctivitis with single-dose intramuscular ceftriaxone.

We treated 13 consecutive patients with culture proven Neisseria gonorrhoeae conjunctivitis with single-dose intramuscular injections of ceftriaxone. Pretreatment conjunctival cultures and Gram stains were obtained from all patients. The patients were admitted for antibiotic administration, a single conjunctival saline lavage, and follow-up conjunctival cultures six and 12 hours after treatment. Three of 13 organisms (23%) were penicillinase producing. All patients responded to treatment, and all six- and 12-hour posttreatment cultures were negative for N. gonorrhoeae. These results indicate that a single intramuscular dose of ceftriaxone is curative treatment for non-neonatal gonococcal conjunctivitis.

Delayed-onset pseudophakic endophthalmitis.

We reviewed 19 cases of delayed-onset pseudophakic endophthalmitis in which diagnostic cultures were performed at one month or more after cataract extraction with posterior chamber intraocular lens implantation. We isolated four different organisms in these 19 cases: 12 Propionibacterium species (63%), three Candida parapsilosis (16%), three Staphylococcus epidermidis (16%), and one Corynebacterium species (5%). Because of the unusual delayed-onset features of these cases and the retrospective nature of this study, a variety of treatment regimens were used. Twelve patients had recurrence of marked inflammation despite an apparent initial cure, and ten of these patients had positive culture results on repeat examination of intraocular fluids. Nine patients continued to be treated with topical corticosteroids postoperatively to suppress low-grade inflammation. Of the 19 patients, 16 had final visual acuity of 20/400 or better. Delayed-onset pseudophakic endophthalmitis had a more favorable visual prognosis, compared to acute-onset endophthalmitis.

Postoperative mycobacterial endophthalmitis.

We treated two sporadic cases of postoperative endophthalmitis caused by rapidly growing (Runyon's group IV) mycobacteria. Both involved intraocular lenses, one a secondary implant after intracapsular cataract extraction (Mycobacterium chelonae subspecies abscessus) and the other a primary posterior chamber lens implantation after extracapsular cataract extraction (pigment-producing member group IV). Signs of inflammation were judged severe enough to warrant diagnostic and therapeutic intervention during the fourth postoperative week in both cases. In both eyes the organism seemed to be eradicated by intravitreal amikacin in combination with vitrectomy, as well as topical, subconjunctival, and, in one case, systemic antibiotic therapy.

Fuchs's heterochromic cyclitis and posterior capsulotomy.

We report a case of intractable glaucoma following an uncomplicated secondary posterior capsulotomy in a 48-year-old male with Fuchs's heterochromic cyclitis. The patient had been free of inflammation and glaucoma since cataract extraction 27 years previously. We also report the results of phenotypic analysis of lymphocytes removed from the anterior chamber.

Capnocytophaga keratitis.

We report two cases of bacterial keratitis caused by Capnocytophaga, a genus of capnophilic Gram negative bacilli. Both responded to topical and subconjunctival clindamycin.

Results of large penetrating keratoplasty in microbial keratitis.

Extensive corneal disease secondary to microbial keratitis can result in frank or impending corneal perforation requiring a large penetrating keratoplasty. In an 8-year period, 26 penetrating keratoplasties with recipient beds of > or = 9.5 mm were performed on 22 eyes: 11 for bacterial keratitis, 10 for fungal keratitis, and one for a mixed bacterial and fungal keratitis. The graft failed in 18 of 19 eyes (94.7%), with a median time to failure of 12.9 weeks in bacterial keratitis and 4.0 weeks in fungal keratitis. After large keratoplasty, 17 of 20 eyes (85.0%) maintained the structural integrity of the globe. The remainder became phthisical or required enucleation. With preservation of the structural integrity of the globe, a subsequent smaller optical penetrating keratoplasty is an option in some of these eyes.

Growth curve for Propionibacterium acnes.

We established growth curves for Propionibacterium acnes isolates recovered from eyes with chronic postoperative endophthalmitis. The growth curve plotted the average of the duplicate bacterial concentration against time. The generation time for P. acnes calculated from the growth curves was approximately 5.1 hours. The growth of P. acnes is slower than other anaerobic bacteria. This may account for its delayed appearance in culture of ocular specimens. It may also explain treatment failure if the concentration of an antibiotic injected into the vitreous does not remain at an effective level during the critical replicative phase of the organism.

Acanthamoebic keratitis in a healthy Australian man.

We report a case of acanthamoebic keratitis that occurred after minor ocular trauma in a healthy 31-year-old man. Multiple microbiological investigations failed to reveal the causative organism, which was identified as Acanthamoeba castellanii only after a corneal graft operation had been performed. A review of previously described cases reveals that this rare ocular infection tends to cause recalcitrant corneal ulcers after minor eye injuries in otherwise healthy individuals.

Postoperative Propionibacterium endophthalmitis. Treatment strategies and long-term results.

PURPOSE: Postoperative Propionibacterium endophthalmitis is a condition characterized by exacerbations and remissions that has often been accompanied by recurrence after treatment. The purpose of this study is to evaluate the efficacy of initial therapies in preventing recurrent endophthalmitis and to assess the safety of intraocular lens (IOL) exchange performed during treatment of active endophthalmitis. METHODS: The records of 22 patients with culture-proven Propionibacterium endophthalmitis treated at one facility were retrospectively reviewed. RESULTS: Two patients presented acutely, were treated with intraocular antibiotic injection alone, and experienced no recurrent inflammation. Twenty patients presented with chronic, delayed-onset pseudophakic endophthalmitis. Eight of these were treated initially with intraocular antibiotic injection alone, and recurrent endophthalmitis developed in seven. Twelve patients with chronic endophthalmitis were initially managed surgically with either pars plana vitrectomy or IOL exchange. Four of the 12 experienced recurrent endophthalmitis. Patients undergoing capsulectomy as part of initial management experienced the lowest rate of recurrent endophthalmitis. Eight patients eventually underwent total capsulectomy and IOL explantation, seven of whom had IOL exchange. None of these eight patients had recurrent endophthalmitis. In seven of the eight, persistent bacterial colonization of the lens capsular remnants was demonstrated. CONCLUSIONS: These data suggest that recurrent Propionibacterium endophthalmitis is due to persistence of viable organisms sequestered within lens capsular remnants, and that initial therapy directed toward surgical removal of these sequestered organisms results in a reduced frequency of recurrent endophthalmitis. Intraocular lens exchange with complete capsular removal during active endophthalmitis was not associated with recurrent or persistent endophthalmitis.

Artificial orbit system for experimental surgery with enucleated globes.

A portable system for holding, accurately positioning, and restoring the physiologic integrity of enucleated globes during experimental anterior segment procedures and pars plana vitrectomy is described. A 0 to 500-mm Hg vacuum fixation ring and positioning apparatus mechanically locks globes into known spatial position while they are supported in a 2 to 6-mm Hg pressurized, pliable socket designed to match the size and pressure of a natural orbit. A gravity infusion system and an implantable piezoelectric pressure sensor in conjunction with a syringe and stopcock assembly allow for controlled inflation of globes to intraocular pressure (IOP) levels from 0 to 70 mm Hg, and to over 300 mm Hg. The fixation vacuum level, and intraocular and extraocular pressures are simultaneously monitored on 3-digit LED displays, and permanent records of each can be generated by routing data to storage devices. The anterior segment remains accessible at all times for surgical procedures and diagnostic measurements. The entire system is portable, allowing globes to be transported to multiple experimental stations, while all pressure settings and the position of the globe are maintained. To demonstrate applications of the artificial orbit system, we describe experiments using it to calibrate applanation tonometers, and to study the relationship between IOP and corneal curvature as well as the effect of trephination procedures and limbal vacuum fixation on IOP.

Management options for Propionibacterium acnes endophthalmitis.

The authors reviewed the management of nine culture-proven cases of Propionibacterium acnes endophthalmitis which presented at an average of 4 months after extracapsular cataract extraction (ECCE) and posterior chamber intraocular lens (PC IOL) implantation. The initial signs included a white intracapsular plaque (9/9), vitritis (9/9), granulomatous uveitis (4/9), nongranulomatous uveitis (5/9), hypopyon (4/9), beaded fibrin strands in the anterior chamber (3/9), and diffuse intraretinal hemorrhages (2/9). A variety of management schemes were used in these patients, including the following: topical and intravenous antibiotics alone; intraocular and topical antibiotic administration; pars plana vitrectomy with capsulectomy and intraocular antibiotic administration; and removal of all capsular remnants with PC IOL removal or exchange. The final visual acuities ranged from 20/20 to 20/60 in six eyes and 20/200 to 20/400 in three eyes. This review suggests that a variety of management options for P. acnes endophthalmitis appear to be successful. Based on the authors' experience, an algorithm for future treatment is offered.