Repair of inadvertent conjunctival filtering blebs with a scleral flap.

We describe a new technique to correct inadvertent conjunctival filtering blebs. This method creates a partial-thickness scleral flap to seal the region of the excised fistula. Closure of this flap with sutures permanently covers the fistula and eliminates any route for recurrence of the bleb or downgrowth of epithelium. No complications have been associated with this procedure, which has been used in more than 10 cases during the last 3 years.

In vivo observation of tear dynamics using fluorophotometry.

Fluorophotometry was used to evaluate the effect of the blinking process on tear spreading. In normal individuals, when the intensity of fluorescence was monitored over the central 1 mm of the cornea, forceful blinking was found to substantially increase tear film thickness. Weak blinking was found to decrease tear film thickness. When tear film fluorescence was monitored along different regions of the corneal vertical meridian, the tear film thickened superiorly while thinning inferiorly. It is postulated that the vertical spreading of meibomian oils is accompanied by the movement of a portion of the aqueous tear phase that thickens the superior tear film at the expense of thinning inferiorly.

Schirmer's test. A closer look.

In 50 normal subjects, results of kinetics studies of Schirmer's test demonstrated nonlinear wetting with an initial rapid phase of wetting followed by a progressive reduction in rate. This initial rapid phase of wetting indicated a reflex secretion of tears. In the majority of subjects, topical anesthesia with 0.5% proparacaine hydrochloride dampened the initial reflex secretion but could not completely suppress it. The data indicated that Schirmer's test with anesthesia was not capable of measuring a basic tear secretion independent of reflex components.

Infantile endogenous Candida endophthalmitis presenting as a cataract.

The most common pathogen to cause endogenous endophthalmitis is the fungus Candida albicans. Most cases involve adults who are either immunosuppressed or have a history of repeated or prolonged extracorporeal access to their circulatory system. Endogenous Candida endophthalmitis can occur in infants as well, particularly when prematurity, broad spectrum antibiotic therapy, or prior surgery are present as predisposing factors. We report the clinical and histopathological findings of an infant who developed a unilateral, sectoral lens opacity four months after undergoing treatment for disseminated candidiasis. The diagnosis of localized intralenticular fungal abscess with associated endophthalmitis was made via histopathologic examination of the aspirated lens material. Treatment with systemic antifungal agents successfully preserved the eye. In addition, we review and summarize the previously reported cases of Candida endophthalmitis in patients under one year of age.

Testing for hepatitis B surface antigen in processing donor tissue for penetrating keratoplasty.

PURPOSE: The Food and Drug Administration recently proposed a change in the screening of eye bank cornea donors for hepatitis B virus. Currently, most eye banks run confirmatory tests to reduce the frequency of false-positive hepatitis B virus surface antigen (HBsAg) tests. The Food and Drug Administration is considering a policy that would not allow confirmatory testing. METHODS: A retrospective study of records of a regional eye bank was done to evaluate the results of screening and confirmatory tests for hepatitis B virus. RESULTS: The positive predictive value of the HBsAg screening test (using hepatitis B virus antibody neutralization for comparison) was low, 12.5%. False-positive donors accounted for 11.4% of the tissue used for penetrating keratoplasty during 1994. CONCLUSIONS: If confirmation tests were not allowed, considerable loss of suitable tissue would have occurred. We believe that the current standards allow safe and effective processing of donor ocular tissue.

Sloughing of corneal epithelium and wound healing complications associated with laser in situ keratomileusis in patients with epithelial basement membrane dystrophy.

PURPOSE: To report sloughing of corneal epithelium during laser in situ keratomileusis and subsequent wound healing complications in patients with epithelial basement membrane dystrophy. METHODS: In a retrospective study, the surgical procedures, postoperative course, and visual acuities of 16 eyes of nine patients with epithelial basement membrane dystrophy who underwent laser in situ keratomileusis complicated with epithelial sloughing at three centers were reviewed. The mean follow-up period was 23 weeks (range, 4 to 52 weeks). RESULTS: In 13 (81%) of 16 eyes with epithelial basement membrane dystrophy, epithelial sloughing occurred during laser in situ keratomileusis. In eight of the 13 eyes, epithelial growth beneath the flap was observed. The flap was lifted and the interface epithelium scraped in six eyes. Flap melt or keratolysis occurred in four eyes. At the last follow-up visit, 13 of 16 eyes had an uncorrected visual acuity of 20/30 or better, and all eyes had a best-corrected visual acuity of 20/30 or better. CONCLUSIONS: Patients with epithelial basement membrane dystrophy have poorly adherent corneal epithelium and are predisposed to epithelial sloughing during the microkeratome pass of laser in situ keratomileusis. This may lead to flap distortion, interface epithelial growth, flap keratolysis, and corneal scarring. It is not recommended that laser in situ keratomileusis be performed in patients with classic, symptomatic epithelial basement membrane dystrophy. In patients who present with mild and asymptomatic epithelial basement membrane dystrophy, laser in situ keratomileusis should be performed with caution, or photorefractive keratectomy may be the preferred refractive procedure.

Comparison of visual results in initial and re-treatment laser in situ keratomileusis procedures for myopia and astigmatism.

PURPOSE: To report the results of initial and re-treatment laser in situ keratomileusis procedures for myopia and astigmatism. METHODS: A total of 1161 consecutive inital and retreatment laser in situ keratomileusis procedures in 697 patients performed between September 19, 1996, and June 20, 1998, were retrospectively analyzed. Baseline and postoperative best spectacle-corrected visual acuity, uncorrected visual acuity, spherical and cylindrical refractions, computerized video keratography, and biomicroscopy were measured or performed on each eye. RESULTS: Of 1,071 eyes, 900 (84%) underwent a single-laser in situ keratomileusis procedure, and 171 of 1,071 eyes (16%) underwent one or two re-treatment procedures. The preoperative mean +/- SD spherical equivalent was -5.09 +/- 3.15 diopters (range, -0.75 to -14.38 diopters) and the cylinder was 0.97 +/- 1.09 diopters (range, 0.00 to 3.25 diopters) in the group that underwent a single laser in situ keratomileusis treatment. The preoperative mean +/- SD spherical equivalent was -6.26 +/- 3.04 diopters (range, -1.75 to -12.88 diopters) and the cylinder was 1.53 +/- 1.11 diopters (range, 0.00 to 3.50 diopters) in the group that underwent re-treatment. Before re-treatment, 110 eyes (64.3%) in the group that underwent re-treatment achieved 20/40 or better uncorrected visual acuity and 23 eyes (13.5%) achieved 20/25 or better. Three months after re-treatment, 155 eyes (90.6%) achieved 20/40 or better, and 80 eyes (46.8%) achieved 20/25 or better. In the single-procedure group, uncorrected visual acuity at 3 months revealed 20/40 vision or better in 856 eyes (95.1%) and 20/25 vision or better in 572 eyes (63.6%). In this study group, 23.6% of eyes with a preoperative spherical equivalent greater than -6.0 diopters underwent re-treatment compared with 11.8% of eyes with a preoperative spherical equivalent of -6.0 diopters or less. CONCLUSIONS: Laser in situ keratomileusis appears to be an effective procedure for mild, moderate, and severe myopia. In eyes with residual refractive error, re-treatment laser in situ keratomileusis procedures can result in good visual outcomes.

An adjustable double running suture technique for keratoplasty.

In a retrospective analysis, we examined 30 consecutive cases of penetrating keratoplasty in which a double running 10-0/11-0 nylon suture technique was used and the 10-0 suture was adjusted early in the postoperative period to reduce astigmatism. When the response to suture adjustment was inadequate, the presence of the 11-0 suture allowed for early (ten to 18 weeks) removal of the 10-0 suture. Rapid visual recovery (12.3 +/- 0.95 weeks; mean +/- standard error) and low levels of final astigmatism (2.66 +/- 0.24 diopters) were achieved. Visual acuity was 20/20 to 20/40 in 25 of the 28 patients (89%) who were visually rehabilitated. In these 28 patients, visual acuity remained stable for the remainder of the study. All patients had a minimum of six months' follow-up from the time of surgery; mean follow-up was 10.6 +/- 1.70 months.

Infected vs sterile corneal infiltrates in contact lens wearers.

We examined 50 patients to determine whether differences exist between the initial clinical signs and symptoms associated with infected vs sterile corneal infiltrates. A detailed history regarding contact lens use and ocular symptoms was taken, after which a careful slit-lamp examination was performed. The ocular findings were correlated with the results of corneal cultures. Increased pain (P less than .001), discharge (P less than .0001), epithelial staining (P less than .0001), and anterior chamber reaction (P less than .0001) were associated with infected ulcers. Sterile infiltrates were usually smaller; multiple or arcuate; and without significant pain, epithelial staining, or anterior chamber reaction.

Fungal keratitis from nylon line lawn trimmers.

Ocular trauma from nylon line lawn trimmers is becoming more prevalent. Previous case reports have described penetrating trauma caused by these tools. We managed three cases of fungal keratitis caused by injuries from nylon line trimmers. Fungal keratitis should be strongly considered as the cause of any corneal ulcer related to trauma from a nylon line lawn trimmer.

Microbial keratitis in children.

In a five-year review, we identified 29 cases of microbial infection in 28 patients who were 16 years old or younger. Herpes simplex infections were excluded. Predisposing factors included trauma (ten cases, 34%), severe systemic illness (eight cases, 27%), contact lens use (seven cases, 24%), exposure keratopathy (seven cases, 24%), and previous ocular surgery (six cases, 21%). A total of 24 microorganisms were identified in cultures of corneal scrapings from 22 of the 29 cases; two cases involved polymicrobial infections. Of the 24 identified pathogens, gram-positive cocci were the most common (12). Other microorganisms included gram-negative bacteria (five) and fungi (four). Isolated cases of Acanthamoeba species, Borrelia burgdorferi, and Bacillus species were also present. Therapy with intensive topical antibiotics was successful in this series. The rate of surgical intervention (6/29, 21%) was similar to that of previous reports.

Clear corneal cataract surgery in ocular cicatricial pemphigoid.

We present the results of clear corneal cataract surgery in a patient with stable ocular cicatricial pemphigoid. By eliminating trauma to the conjunctiva, cataract surgery was successfully performed without exacerbating the disease.

Decentration of 3-piece versus plate-haptic silicone intraocular lenses.

PURPOSE: To compare the incidence of decentration with 2 types of silicone intraocular lenses (IOLs). SETTING: John A. Moran Eye Center, University of Utah Medical Center, Salt Lake City, Utah, USA. METHODS: Selection criteria for this retrospective study included patients who had uncomplicated cataract surgery with a clear cornea or scleral tunnel incision with a curvilinear capsulorhexis and capsular bag implantation of a silicone IOL. After a mean follow-up of 14 months (range 12 to 18 months), 54 eyes implanted with a 3-piece lens (AMO SI-30) and 58 eyes implanted with a plate-haptic lens (Staar AA403) were examined for posterior chamber IOL decentration. The decentration criterion was 0.5 mm or more from the center of the pupil. Detailed chart review of preoperative and postoperative measurements was performed for each patient. RESULTS: Eighteen of the 3-piece IOLs (33%) and 11 of the plate-haptic IOLs (20%) were decentered 0.5 mm or more (P = .129). Using photographic analysis, the mean IOL decentration with the 3-piece IOL (1.12 mm +/- 0.198 [SD]) was significantly greater than with the plate-haptic IOL (0.632 +/- 0.278 mm)(P < .001). No statistically significant correlation was found between the centered or decentered IOL groups' preoperative refraction, axial length, capsulorhexis size, type of incision, or rate of neodymium:YAG laser capsulotomy. CONCLUSIONS: No statistically significant difference was seen between the decentration rates of 3-piece and plate-hepatic IOLs; however, the amount of decentration with the 3-piece IOL was significantly greater than with the plate-hepatic IOL. Other factors did not contribute to IOL decentration.

Initial results of photorefractive keratectomy and laser in situ keratomileusis performed by a single surgeon.

PURPOSE: To determine the safety and efficacy of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) early in a surgeon's experience. SETTING: Ophthalmology Department, John A. Moran Eye Center, Salt Lake City, Utah, USA. METHODS: Between October 1995 and April 1997, a retrospective analysis was performed of 200 eyes in 128 patients who had PRK or LASIK with a follow-up of at least 3 months. The mean age was 38.1 years +/- 10.4 (SD) in the PRK group and 42.3 +/- 10.1 years in the LASIK group. There were 36 women and 30 men in the former and 32 women and 30 men in the latter. Photorefractive keratectomy, PRK/astigmatic keratotomy (AK), LASIK, or LASIK/AK was performed with the Summit Omnimed excimer laser. Preoperative evaluation included uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), cycloplegic refraction, tonometry, and computerized videokeratography. At 1, 3, and 6 months, UCVA, BSCVA, mean spherical equivalent (SE), astigmatism, corneal haze, subjective vision (day, night, glare, and halo), and complications were measured. RESULTS: Mean SE was 0.16 +/- 0.82 diopter (D) in the PRK group and -0.09 +/- 0.63 D in the LASIK group at 1 month (P < .05), -0.18 +/- 0.66 D and -0.16 +/- 0.58 D, respectively, at 3 months, and -0.33 +/- 0.73 D and -0.09 +/- 0.62 D, respectively, at 6 months. Achieved correction was similar in the 2 groups. Mean BSCVA was 22.8 +/- 6.0 in the PRK group and 22.2 +/- 5.3 in the LASIK group at 1 month, 21.1 +/- 6.0 and 21.1 +/- 3.1, respectively, at 3 months, and 19.8 +/- 3.5 and 22.9 +/- 5.2, respectively, at 6 months (P < .005). Mean surface regularity index was 0.68 +/- 0.40 in the PRK group and 0.86 +/- 0.41 in the LASIK group at 1 month, 0.54 +/- 0.26 and 0.72 +/- 0.37, respectively, at 3 months (P < .05), and 0.49 +/- 0.27 and 0.84 +/- 0.42, respectively, at 6 months. Mean surface asymmetry index was 0.71 +/- 0.43 in the PRK group and 0.55 +/- 0.21 in the LASIK group at 1 month (P < .05), 0.53 +/- 0.24 and 0.51 +/- 0.23, respectively, at 3 months, and 0.46 +/- 0.19 and 0.64 +/- 0.54, respectively, at 6 months. The subjective parameters between the groups were significantly different only at 6 months; patients in the PRK group reported better day and night vision. CONCLUSION: With careful preparation and proper training, PRK and LASIK appear to be safe and efficacious even during the surgeon's early learning phases.

Penetrating keratoplasty for keratoconus: a long-term review of results and complications.

PURPOSE: To study the long-term complications of penetrating keratoplasty (PKP) to evaluate current recommendations to patients with keratoconus. SETTING: John Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. METHODS: Retrospective study of all PKP procedures for keratoconus performed by 4 surgeons during a 312 year period. Follow-up was 1 day and 1, 3, 6, 12, and 24 months post-PKP. Data from 93 eyes were reviewed for allograft reaction, astigmatism, visual acuity, reasons for decreased visual acuity, and other complications. RESULTS: Allograft reaction was seen in 31% of cases but no graft failure due to allograft reaction. Mean astigmatism was 2.76 diopters (D) +/- 1.99 (SD) at 24 months, with only 15% > 5.00 D. Last best corrected visual acuity was 20/25 or better in 77% of cases (87% had 20/25 or better at some time during follow-up). Complications that did not cause decreased visual acuity were noted. Punctate keratitis was noted in 20% of patients 180 days or more after surgery. CONCLUSIONS: Penetrating keratoplasty is a good treatment option for patients with keratoconus but should be reserved for those who do not tolerate contact lenses or do not get needed visual acuity with contact lenses because of complications. This procedure has become a second-line treatment for keratoconus patients and has generally good results.

Prospective evaluation of topical versus retrobulbar anesthesia: a converting surgeon's experience.

PURPOSE: To evaluate and compare the efficacy of topical versus retrobulbar anesthesia for cataract surgery performed by a surgeon newly converting to the topical technique. SETTING: Department of Ophthalmology, Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. METHODS: Ninety patients were prospectively assigned by permuted block restricted randomization to receive topical (Group 1; n = 45) or retrobulbar (Group 2; n = 45) anesthesia. Group 1 received topical bupivacaine 0.75% and intravenous midazolam and fentanyl for anesthesia. Group 2 received intravenous methohexital followed by retrobulbar block with an equal mixture of lidocaine 2% and bupivacaine 0.75% plus hyaluronidase 150 units. A visual pain analog scale was used to assess the degree of pain during anesthesia administration and surgery and postoperatively. The degree to which eye movement, touch, and light caused patient discomfort was assessed. Intraoperative conditions and complications were recorded. RESULTS: Intraoperative operating conditions were significantly better in Group 2 (P < .05). There was a small but statistically significant difference in the degree of discomfort during anesthesia administration and surgery (P < .05). There was no difference in postoperative discomfort. Chemosis, subconjunctival hemorrhage, and eyelid hemorrhage occurred only in Group 2, in which there was one retrobulbar hemorrhage. Although eyelid squeezing and ocular motility were present more frequently in Group 1, neither was a problem to the surgeon. CONCLUSION: Cataract surgery was safely performed by a surgeon converting to topical anesthesia. After a distinct learning curve, the procedure was performed with minimal patient discomfort. Surgical training and patient preparation are the key to safe use of topical anesthesia.

Efficacy of tobramycin drops applied to collagen shields for experimental staphylococcal keratitis.

Treatment of staphylococcal keratitis includes tobramycin drops at repeated intervals, a prolonged therapy that is disruptive to the patient. To identify a regimen involving less frequent drug application, we compared the efficacy of fortified tobramycin (1.36%) administered by collagen shields or in topical drop form to rabbit corneas intrastromally infected with staphylococci. Eyes were treated with shields hydrated in and supplemented with fortified tobramycin drops (1.36%) applied every 1, 2, 5, or 10 h, from 10 to 20 h postinfection. For topical drop treatment alone, tobramycin was applied following the identical regimen. Untreated corneas contained 10(6) colony forming units. Shields supplemented with tobramycin drops applied every 1, 2, or 5 h sterilized 100% of the corneas. Shields supplemented with tobramycin drops applied at 10 h sterilized 58% of the corneas. Topical delivery of tobramycin every h sterilized all corneas; drops alone applied at longer intervals, such as 2, 5, or 10 h, sterilized 83%, 17%, and 0% of the corneas, respectively. Collagen shield delivery of tobramycin with supplemental topical drops can eradicate staphylococci in this model with less frequent dosing intervals than are required with topical therapy alone.

Phototherapeutic keratectomy for corneal scars.

BACKGROUND AND OBJECTIVE: Phototherapeutic keratectomy (PTK) is an effective method of treating a variety of corneal disorders. We report our experience in using PRK to treat corneal scars. PATIENTS AND METHODS: We retrospectively analyzed the data from a cohort of 22 eyes with corneal scars. The etiology of the scar was recorded for each patient. The change in best corrected visual acuity, spherical equivalent, and astigmatism were evaluated at one and three months after surgery. RESULTS: At three months, seven of 18 eyes (39%) had improved 2 or more lines of best corrected visual acuity and 3 eyes (16%) had lost 2 or more lines. Eleven of 18 eyes (61%) had a hyperopic shift of more than 1.00 diopter (D) and eight of 18 eyes (44%) had a hyperopic shift of more than 2.00 D. There was a mean reduction in astigmatism of 0.67 +/- 4.00 D. Four of eight eyes with traumatic scars had significant improvement as compared to none of five eyes with infectious scars. CONCLUSION: PTK is a relatively safe and effective means of treating corneal scars and thereby may offer an alternative to corneal transplantation.