Jay C. Bradley

Boston type 1 keratoprosthesis: the university of california davis experience.

Purpose: To compare the University of California Davis experience using the Boston keratoprosthesis with the Boston Keratoprosthesis Study Groups initial report. Design: Retrospective chart review. Participants: We analyzed 30 eyes of 28 patients who previously underwent Boston type 1 keratoprosthesis surgery at our institution between 2004 and 2008. Methods: Preoperative, intraoperative, and postoperative parameters were collected and analyzed. Main Outcome Measures: Visual acuity and keratoprosthesis stability. Results: Preoperative diagnoses were failed graft (26 eyes, 87%), chemical injury (3 eyes, 10%), and Stevens-Johnson syndrome (1 eye, 3%). Twenty eyes (66%) had preoperative glaucoma. Preoperative best-corrected visual acuity ranged from 20/150 to light perception and was <20/200 in 83% of eyes. At an average follow-up of 19 months (range, 1-48; SD, 13.8; and median, 13), postoperative vision improved to ≥20/200 in 77% of eyes. Among eyes at least 1 year after the operation (16 eyes), vision was ≥20/200 in 75% of eyes and ≥20/40 in 25% of eyes. At an average follow-up of 19 months, retention of the initial keratoprosthesis was 83.3%. Conclusions: The Boston type 1 keratoprosthesis is a viable option after multiple keratoplasty failures or in conditions with a poor prognosis for primary keratoplasty. Patients with autoimmune disease are at higher risk for complications. The University of California Davis experience seems equivalent to the initial report of the Boston Keratoprosthesis Study Group. With longer follow-up, additional surgical procedures may be required but good anatomic and functional outcomes can be maintained.

The science of pterygia

Pterygium is an ocular surface disease of humans attributed to chronic ultraviolet-B exposure. Clinically, the condition involves invasive centripetal growth with associated inflammation and neovascularisation. Previous clinical studies focused primarily on the clinical characteristics and surgical management of pterygia and, because of this, the pathogenesis of pterygia remains incompletely understood. However, considerable progress in this area has been achieved, providing additional insight into this complex disease. This recent evidence implicates antiapoptotic mechanisms, immunological mechanisms, cytokines, growth factors, extracellular matrix modulators, genetic factors, viral infections and other possible causative factors. Limited investigation regarding differences in pathogenesis of primary and recurrent pterygia has been performed. We summarise many of these recent discoveries concerning the pathogenesis of pterygia and describe reported differences between primary and recurrent pterygia.

Candida glabrata Endophthalmitis Treated Successfully with Caspofungin

A 39-year-old man with Candida glabrata endophthalmitis was successfully treated with a 28-day course of intravenous caspofungin. Presence of underlying renal insufficiency and infection with a drug-resistant strain precluded use of amphotericin B or fluconazole. Intravitreal administration of antifungals and vitrectomy were not required. The role of caspofungin in Candida endophthalmitis is discussed.

Time- and temperature-dependent stability of growth factor peptides in human autologous serum eye drops.

Purposes: To develop a step-by-step production method for human autologous serum (AS) eye drops that was broadly compliant with US Food and Drug Administration requirements for reinjection of processed biological substances. To determine optimum storage conditions for AS eye drops by measuring the concentration of growth factor peptides (GFP) as a function of storage temperature and storage duration. Methods: AS derived from the blood of 3 healthy male volunteers was produced using a closed, vacuum-driven, cascade-filtration system under sterile, low-pyrogen conditions. In-process controls included methods for monitoring protein electrophoretic mobility and degradation rate and the content of free hemoglobin and endotoxin. Stability of transforming growth factor β1, substance P, nerve growth factor, calcitonin gene-related peptide, insulin-like growth factor 1, and epidermal growth factor was evaluated at -15°C, +4°C, +25°C, +37°C, and +42°C at different time intervals (hours to weeks). The main outcome measures were the concentrations of GFP, endotoxin, and lipid peroxidation by-products (a proxy measure for protein degradation) in dilute AS. Results: The stability of GFP varies: transforming growth factor β1, nerve growth factor, epidermal growth factor, and insulin-like growth factor 1 were more temperature and time resistant, but substance P and calcitonin gene-related peptide significantly degraded at +4°C in 24 hours. Endotoxin and lipid peroxidation by-products were not significantly increased by processing. Conclusions: This pilot study developed a closed, cascade-filtration system that was an effective method for the production of high-quality, low-pyrogen AS. The processing method broadly complied with Food and Drug Administration requirements for reinjection of biological substances. Variable GFP stability was observed at +4°C and above. For clinical use, AS should be packaged in daily-use containers, which should be stored frozen; the container in active use should be refrigerated between doses.

Comparison of Colvard pupillometer and infrared digital photography for measurement of the dark-adapted pupil diameter

PURPOSE: To investigate the accuracy of pupil diameter measurement using the Colvard pupillometer and to determine the learning curve for inexperienced examiners. SETTING: Texas Tech University Health Sciences Center, Lubbock, Texas, USA. METHODS: In this population study, subjects with normal pupillary behavior were tested by 1 of 2 investigators (examiner A, examiner B). After 5 minutes of dark adaptation at 1 lux, digital infrared pupil photography of the right eye was performed, followed by measurement of the horizontal pupil diameter and vertical pupil diameter with the Colvard pupillometer. The photographs were digitally analyzed to determine the horizontal and vertical pupil diameters. During phase I of the study, examiners were masked to the results of infrared pupil photography; during phase II, they reviewed the infrared pupil photography results after each testing session. Bland‐Altman plots were created to detect measurement bias; results were graphed by subject test sequence to assess learning. A test difference of less than ±0.5 mm was considered clinically acceptable. RESULTS: Fifty‐nine subjects were tested in phase I, of whom 39 had adequate infrared pupil photography for analysis; 40 were tested in phase II, of whom 34 were included. The mean age of the analyzed subjects was 27 years (range 18 to 44 years). For all subjects, the infrared pupil photography median horizontal pupil diameter was 7.09 mm ± 0.75 (SD) (range 5.44 to 8.79 mm); the median vertical pupil diameter was 7.22 ± 0.79 mm (range 5.45 to 9.10 mm). Examiner A initially had a negative bias (Colvard pupillometer value less than infrared pupil photography value) for both horizontal and vertical pupil diameter measurements, which resolved during phase I after 23 subjects were tested; 18 of the final 19 subjects tested (11 phase I, 8 phase II) showed a test difference of less than 0.5 mm for all readings. The pupil diameter did not affect the bias. Examiner B had a strong positive bias that persisted throughout the study. Testing 26 subjects in 5 sessions during phase II did not improve the accuracy. During the final testing session, 3 of 8 subjects had a test difference of 0.5 mm or more in at least 1 dimension. The pupil diameter did not affect the bias. CONCLUSION: The Colvard pupillometer is susceptible to user errors causing unidirectional bias and seems to have a steep and variable learning curve.

Continuous intraocular pressure recordings during lamellar microkeratotomy of enucleated human eyes

PURPOSE: To analyze the course of intraocular pressure (IOP) during lamellar microkeratotomy (LMK) in enucleated human eyes using 3 microkeratome systems. SETTING: Department of Ophthalmology, Texas Tech University Health Sciences Center, Lubbock, Texas, U.S.A. METHODS: Sixteen enucleated human globes were cannulated through the optic nerve, and IOP was recorded continuously while the eyes had standard LMK flap creation. Three microkeratomes were used: Carriazo‐Barraquer (Moria Inc.), Innovatome (Innovative Optics Inc.), and Hansatome (Bausch & Lomb). RESULTS: During the vacuum affixation phase, the IOP reached a mean plateau of 97.9 mm Hg with the Hansatome, 135.8 mm Hg with the Innovatome, and 150.0 mm Hg with the Carriazo‐Barraquer. During applanation and cutting, the IOP rose to mean plateau of 154.7 mm Hg, 151.8 mm Hg, and 175.8 mm Hg, respectively. Statistical analysis using Kruskal‐Wallis testing suggested a difference in mean IOP elevation between the 3 microkeratomes during the vacuum affixation phase (P = .0394) but no difference during the applanation and cutting phase (P = .506). CONCLUSION: The IOP during LMK was higher than previously reported, and this may increase the risk for complications in certain patient groups.

Visual field changes after laser in situ keratomileusis.

Purpose: To determine whether laser in situ keratomileusis (LASIK) affects the central 30‐degree visual field. Setting: University‐based ophthalmology practice. Methods: This nonrandomized clinical trial comprised 14 normal patients (27 eyes) scheduled to have LASIK for myopia or myopic astigmatism. Automated static perimetry was performed before and 6 months after surgery using the Octopus 1‐2‐3 perimeter and the Dynamic‐32 test strategy. Patient data included sex, age, preoperative and postoperative refractive errors, preoperative and postoperative best corrected visual acuity, preoperative corneal thickness, programmed optical zone, programmed total ablation diameter, and duration of microkeratome suction. All surgery was performed using the same Alcon LADARVision 4000 excimer laser. The main outcome measures were the mean sensitivity (MS) change in the central 15‐degree visual field and the MS change in the 15‐ to 30‐degree visual field. A multivariate analysis of the MS change as a function of preoperative clinical parameters was performed. Results: There was no significant change in the MS in the central 15‐degree visual field; between 15 and 30 degrees, there was a statistically significant decrease of −0.82 dB ± 1.40 (SD) (P = .01, 2‐tailed t test). The decline in MS was positively correlated with refractive error and corneal thickness; it was negatively correlated with the programmed optical zone diameter. Conclusions: Automatic static perimetry can detect decreased sensitivity in the midperipheral visual field after myopic LASIK. It may be a useful quantitative subjective test for measuring the effects of future improvements in surgical technique on vision quality.

Dark-Adapted Pupil Diameter as a Function of Age Measured with the NeurOptics Pupillometer

PURPOSE To measure the dark-adapted pupil diameter of normal research participants in their second through ninth decades of life using the NeurOptics pupillometer (Neuroptics Inc). METHODS Individuals aged 18 to 80 years with no history of eye disease or injury, intraocular surgery, or use of systemic antihistamines or opiates were recruited. After 2 minutes of adaptation at 1 lux illumination, the right dark-adapted pupil diameter was measured using the NeurOptics pupillometer, with accommodation controlled by distance fixation. The NeurOptics pupillometer reported a mean dark-adapted pupil diameter and a standard deviation of the mean, which were analyzed as a function of age-decade. RESULTS Two-hundred sixty-three individuals participated. For participants aged 18 to 19 years (n=6), the mean dark-adapted pupil diameter was 6.85 mm (range: 5.6 to 7.5 mm); 20 to 29 years (n=66), 7.33 mm (range: 5.7 to 8.8 mm); 30 to 39 years (n=50), 6.64 mm (range: 5.3 to 8.7 mm); 40 to 49 years (n=51), 6.15 mm (range: 4.5 to 8.2 mm); 50 to 59 years (n=50), 5.77 mm (range: 4.4 to 7.2 mm); 60 to 69 years (n=30), 5.58 mm (range: 3.5 to 7.5 mm); 70 to 79 years (n=6), 5.17 mm (range: 4.6 to 6.0 mm); and 80 years (n=4), 4.85 mm (range: 4.1 to 5.3 mm). These values were consistent with studies using infrared photography. The standard deviation was >0.1 mm in 10 (3.8%) participants, all of whom were younger than 55 years. CONCLUSIONS The dark-adapted pupil diameter is an important clinical variable when planning refractive surgery. Surgeons can compare a patients dark-adapted pupil diameter with the results of this population study to identify outlier measurements, which may be erroneous, and repeat testing prior to surgery.

Clinical performance of a handheld digital infrared monocular pupillometer for measurement of the dark-adapted pupil diameter

PURPOSE: To compare the accuracy of a handheld infrared digital pupillometer and digital infrared photography for measurement of the dark‐adapted pupil diameter. SETTING: Department of Ophthalmology and Visual Sciences, Texas Tech University Health Sciences Center, Lubbock, Texas, USA. METHODS: The right horizontal pupil diameter in healthy volunteers was measured using a NeurOptics PLR‐200 pupillometer and then videographed using the infrared function of a CyberShot video camera after 2 minutes and 5 minutes dark adaptation at 1 lux ambient illumination. The best still image was extracted from the video file, and the horizontal pupil diameter was determined by comparison against an internal photographic length standard using digital image software. Accommodation and alertness were controlled during testing. RESULTS: The mean horizontal pupil diameter by infrared photography after 2 minutes of dark adaptation by subject age was 7.71 mm for ages 20 to 29 years, 6.80 mm for ages 30 to 39 years, 6.53 mm for ages 40 to 49 years, 5.94 mm for ages 50 to 59 years, and 6.01 mm for ages 60 to 69 years. The mean difference (infrared photography minus pupillometer) was +0.09 mm (range +0.30 to −0.14 mm) at 2 minutes of adaptation and +0.07 mm (range +0.25 to −0.13 mm) at 5 minutes. CONCLUSIONS: The pupillometer accurately measured the horizontal pupil diameter at 1 lux, with no measurement more than 0.3 mm different from infrared photography measurements. The pupillometer had a slight negative bias that is unlikely to introduce an error greater than 0.5 mm in clinical measurements. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Bartonella quintana associated neuroretinitis.

We report an observational case of Bartonella quintana-associated neuroretinitis. The patient had a positive IgM IFA titer for Bartonella quintana early in the disease. After treatment, the neuroretinitis and IgM resolved. Given the patients history, symptoms, response to treatment, and IgM course, we believe his neuroretinitis was secondary to Bartonella quintana.