Intraocular Pressure in Premature Low Birth Weight Infants.

PURPOSE: To evaluate the intraocular pressure (IOP) and central corneal thickness (CCT) in premature low birth weight (LBW) infants and their correlation with gestational age (GA). METHODS: IOP and CCT were measured in premature LBW infants (defined as a birth weight ≤ 1,500 g or birth GA ≤ 30 weeks) admitted to the neonatal intensive care unit at the University of Florida Division of Neonatology, UF Health Jacksonville. RESULTS: Ninety eyes of 45 premature LBW infants with mean birth GA of 28.2 ± 2.3 weeks and mean birth weight of 1,131.5 ± 380.1 g were evaluated. The mean IOP and CCT were 29.0 ± 9.0 mm Hg and 660.0 ± 65.0 µm, respectively. There was no correlation between the IOP and CCT (r = 0.09; P = .38). There was a negative correlation between IOP and GA (r = -0.41) and between CCT and GA (r = -0.26). CONCLUSIONS: IOP is higher and CCT is thicker in premature infants compared to adults; however, there was no correlation between IOP and CCT. [J Pediatr Ophthalmol Strabismus. 2016;53(5):300-304.].

Clinical applications of spectral domain optical coherence tomography in retinal diseases.

Optical coherence tomography (OCT) was introduced about two decades ago and has revolutionized ophthalmic practice in recent years. It is a noninvasive noncontact imaging modality that provides a high-resolution cross-sectional image of the cornea, retina, choroid and optic nerve head, analogous to that of the histological section. Advances in OCT technology in signal detection technique from time-domain (TD) to spectral-domain (SD) detection have given us the potential to study various retinal layers more precisely and in less time. SD-OCT better delineates structural changes and fine lesions in the individual retinal layers. Thus, we have gained substantial information about the pathologic and structural changes in ocular conditions with primary or secondary retinal involvement. This review we discuss the clinical application of currently available SD-OCT in various retinal pathologies. Furthermore, highlights the benefits of SD-OCT over TD. With the introduction of enhanced depth imaging and swept - source OCT visualization of the choroid and choriocapillaris has become possible. Therefore, OCT has become an indispensable ancillary test in the diagnosis and management of diseases involving the retina and/or the choroid. As OCT technology continues to develop further it will provide new insights into the retinal and choroidal structure and the pathogenesis of posterior segment of the eye.

Nampt/PBEF/visfatin serum levels: a new biomarker for retinal blood vessel occlusions.

The main objective of the study was to quantify serum levels of nicotinamide phosphoribosyltransferase (Nampt/pre-B-Cell colony-enhancing factor 1/visfatin) in subjects with a history of retinal vascular occlusions (RVOs), disease conditions characterized by pronounced ischemia, and metabolic energy deficits. A case-control study of 18 subjects with a history of RVO as well as six healthy volunteers is presented. Serum Nampt levels were quantified using a commercially available enzyme-linked immunosorbent assay kit. Serum Nampt levels were 79% lower in patients with a history of RVO compared with that in healthy volunteers (P<0.05). There was no statistically significant difference among the types of RVOs, specifically branch retinal vein occlusions (n=7), central retinal vein occlusions (n=5), hemiretinal vein occlusions (n=3), and central retinal artery occlusions (n=3; P=0.69). Further studies are needed to establish the temporal kinetics of Nampt expression and to determine whether Nampt may represent a novel biomarker to identify at-risk populations, or whether it is a druggable target with the potential to ameliorate the long-term complications associated with the condition, ie, macular edema, macular ischemia, neovascularization, and permanent loss of vision.

Evaluation of the iPad as a low vision aid for improving reading ability.

PURPOSE: To evaluate the effect of the iPad as a low vision aid in improving the reading ability of low vision patients (LVPs). METHODS: In this study, 228 consecutive patients that came for their routine eye care examination at the University of Florida, Jacksonville eye clinic, were enrolled. Patients met inclusion criteria if they had best-corrected visual acuity (BCVA) of 20/100 or worse in the best corrected eye and were willing to participate in the study. The patient's reading ability was assessed both with the patient's own spectacles and an iPad. Patients were encouraged to enlarge the reading material as well as change the contrast until they could read comfortably. The number of patients able to read the text comfortably was recorded. RESULTS: Out of the total 228 participants who qualified, 103 (45%) were male and 125 (55%) were female. Only 22% could read standard newsprint-sized text (N8) without the help of an iPad. With the help of an iPad, 94% participants with impaired vision were able to read standard newsprint-sized text (N8) or smaller text (P<0.01). CONCLUSION: The iPad, a new portable electronic media device, can be adapted by LVPs to improve their reading ability.

A protocol for the retina surgeon's safe initial intravitreal injections.

PURPOSE: To determine the safety of a surgeon's initial consecutive intravitreal injections using a specific protocol and to review the complications that may be attributed to the injection procedure. DESIGN: A retrospective chart review. PARTICIPANTS: Fifty-nine patients (30 females, 29 males) received intravitreal injections of pegaptanib, bevacizumab, or ranibizumab as part of their treatment for neovascular age-related macular degeneration. The average patient age was 80 years. Twenty-two patients were diagnosed with or suspected of having glaucoma. Each patient received an average of 5.8 injections. METHODS: The charts of 59 patients who received a total of 345 intravitreal injections (104 pegaptanib, 74 bevacizumab, 167 ranibizumab) were reviewed. All injections were performed in an office-based setting. Povidone-iodine, topical antibiotics, and eye speculum were used as part of the pre injection procedure. Vision and intraocular pressure were evaluated immediately following each injection. MAIN OUTCOME MEASURES: Incidence of post injection complications, including but not limited to endophthalmitis, retinal detachment, traumatic cataract, and vitreous hemorrhage. RESULTS: There were no cases of endophthalmitis, toxic reactions, traumatic cataracts, retinal detachment, or vitreous hemorrhage. There was one case each of lid swelling, transient floaters, retinal pigment epithelial tear, corneal edema, and corneal abrasion. There were five cases of transient no light perception following pegaptanib injections. CONCLUSION: The incidence of serious complications was very low for the intravitreal injections given. A surgeon's initial intravitreal injections may be performed with a very high degree of safety using this protocol.

Effect of prophylactic intraocular pressure-lowering medication on intraocular pressure spikes after intravitreal injections.

OBJECTIVE: To determine if prophylactic use of intraocular pressure (IOP)-lowering medication is effective in reducing the IOP spikes after intravitreal injections of pegaptanib, bevacizumab, and ranibizumab. METHODS: Seventy-one patients with exudative age-related macular degeneration received intravitreal injections of 1 of 3 anti-vascular endothelial growth factor medications: 30 patients received pegaptanib (0.09 mL), 47 patients received bevacizumab (0.05 mL), and 42 patients received ranibizumab (0.05 mL). Intraocular pressure-lowering medication, 1 hour prior to the injection, was used 63%, 74%, and 66% of the time in eyes that received pegaptanib, ranibizumab, and bevacizumab, respectively. Intraocular pressure was measured prior to injection, within 1 minute after injection, and every 5 to 10 minutes until the pressure was reduced to a safe level. RESULTS: All 3 intravitreal injections caused significant initial IOP spikes (mean [SD] IOP of 38.5 [11.56] mm Hg in the pegaptanib group, 37.75 [8.36] mm Hg in the ranibizumab group, and 34.88 [10.45] mm Hg in the bevacizumab group). The IOP reduced to less than 30 mm Hg in all 3 groups within 20 minutes. Prophylactic medication did not prevent postinjection IOP spikes. Patients with and without glaucoma showed a similar rate of IOP normalization over time in all 3 groups. CONCLUSION: Intraocular pressure spikes after intravitreal injection of pegaptanib, ranibizumab, and bevacizumab are common and in most cases transient. Routine prophylactic use of IOP-lowering medications is essentially ineffective in preventing IOP spikes after intravitreal injection of pegaptanib, ranibizumab, and bevacizumab and therefore not necessary before the injection.

Hyperbaric oxygen therapy for the treatment of radiation-induced macular ischemia.

PURPOSE: To report a case of radiation-induced macular ischemia where vision and macular perfusion improved after hyperbaric oxygen (HBO) therapy. METHODS: A 62-year-old male patient developed radiation-induced macular ischemia after he was treated with radiation for brain glioma. The patient presented with best spectacle-corrected visual acuity (BSCVA) acuity of 20/400 in his right eye. Optical coherence tomography (OCT) showed central macular thickness of 468 mum. The patient received focal laser, intravitreal triamcinolone, and HBO therapy. RESULTS: The patient's vision improved from 20/400 to 20/100 after focal laser and intravitreal triamcinolone. His central macular thickness improved from 468 mum to 132 mum. After receiving HBO therapy, his VA improved to 20/50 and fluorescein angiography showed improvement in macular perfusion. CONCLUSION: HBO therapy improves macular perfusion in patients with radiation-induced macular ischemia.

Fluorophotometry as a diagnostic tool for the evaluation of dry eye disease.

BACKGROUND: Dry eye disease is a common debilitating ocular disease. Current diagnostic tests used in dry eye disease are often neither sensitive nor reproducible, making it difficult to accurately diagnose and determine end points for clinical trials, or evaluate the usefulness of different medications in the treatment of dry eye disease. The recently developed fluorophotometer can objectively detect changes in the corneal epithelium by quantitatively measuring its barrier function or permeability. The purpose of the study is to investigate the use of corneal fluorescein penetration measured by the fluorophotometer as a diagnostic tool in the evaluation of dry eye patients. METHODS: Dry eye patients (16 eyes), who presented with a chief complaint of ocular irritation corresponding with dry eye, low Schirmer's one test (<10 mm after 5 minutes) and corneal fluorescein staining score of more than two, were included in the study. Normal subjects (16 eyes), who came for refraction error evaluation, served as controls. Institutional Review Board (IRB) approved consent was obtained before enrolling the subjects in the study and all questions were answered while explaining the risks, benefits and alternatives. All Fluorophotometry of the central corneal epithelium was done utilizing the Fluorotron Master. Each eye had a baseline fluorescein scan performed, after which 50 l of 1% sodium fluorescein dye was instilled. Three minutes later, the fluorescein was washed with 50 ml of normal saline. Fluorescein scans were then started immediately after washing and were recorded at 10, 20, 40, and 60 minutes thereafter. The corneal peak values of fluorescein concentration were recorded within the central cornea in both dry eyes and in controls. RESULTS: Ten minutes after fluorescein installation, patients with dry eye disease averaged a five-fold increase in corneal tissue fluorescein concentration (mean = 375.26 +/- 202.67 ng/ml) compared with that of normal subjects (mean = 128.19 +/- 85.84 ng/ml). Sixty minutes after dye installation, patients with dry eye disease still revealed higher corneal tissue fluorescein concentration (mean = 112.87 +/- 52.83 ng/ml) compared with that of controls (mean = 40.64 +/- 7.96 ng/ml), averaging a three-fold increase. CONCLUSION: Patients with dry eye disease demonstrated an increased corneal permeability and a slower rate of elimination to topically administered fluorescein when measured by the fluorophotometer. This suggests that fluorophotometry may serve as a valuable quantitative and objective tool for the diagnosis of dry eye disease, and in following patients' response to new treatment modalities. Fluorophotometry may serve as an objective non-invasive tool for end-point analysis in clinical trials of new treatments for dry eye disease.

Conductive keratoplasty and the coupling phenomenon.

PURPOSE: To determine whether changes in corneal astigmatism with astigmatic conductive keratoplasty (CK) treatment obey Gaussian coupling (i.e., the steepening of the flat axis associated with the flattening of the steep axis) and to measure the coupling ratio and the coupling constant to determine the effect of astigmatic CK treatment on spherical equivalent. METHODS: Retrospective review of 33 eyes in 24 patients who had undergone CK for hyperopia and who were treated intraoperatively for induced astigmatism. Induced astigmatism was determined by comparison of keratometric readings before and after CK. RESULTS: The coupling ratio was calculated according to two equations: clinical coupling ratio (1.61 +/- 0.81 diopters) and coupling ratio of the surgically induced refractive change (1.57 +/- 1.16 diopters). Values of the coupling ratio between 0.72 and 1.88 indicate coupling. CONCLUSIONS: The cornea does not behave according to Gauss's law of elastic domes. The targeted flat axis and steep axis 90 degrees away are affected by CK in opposite but not equal amounts. Therefore, when correcting surgically induced astigmatism with CK, the overall spherical equivalent of the patient will change because the coupling ratio is not equal to 1.

Intraoperative correction of induced astigmatism after spherical correction of hyperopia with conductive keratoplasty.

PURPOSE: To evaluate the treatment of surgically induced astigmatism intraoperatively during conductive keratoplasty (CK) for correcting hyperopia. METHODS: Conductive keratoplasty uses radiofrequency energy applied to the peripheral corneal stroma to shrink the collagen and alter the central cornea to correct hyperopia. Nineteen consecutive patients (27 eyes) who underwent CK for hyperopia and were treated intraoperatively for induced astigmatism were examined. By using automated keratometric readings taken during the procedure, additional spots were applied at the minus cylinder or flat axis at the 7-mm zone until the intraoperative astigmatism was 2 diopters (D) or less. RESULTS: The intraoperative treatment reduced the astigmatism by an average of 2.30 +/- 1.32 D (P=0.00001). The mean induced astigmatism was 3.33 +/- 0.14 D for eyes that received eight spots, 4.12 +/- 1.13 D for eyes that received 16 spots, 4.43 +/- 0.82 D for eyes that received 24 spots, and 4.60 +/- 1.08 D for eyes that received 32 spots. Additional spots reduced astigmatism in most patients to less than 2 D. CONCLUSIONS: Intraoperative treatment of astigmatism through the addition of more spots at the minus cylinder or flat axis reduced the degree of induced astigmatism. Surgically induced astigmatism was observed more frequently in patients who received 32 treatment spots and 6-mm treatment zone application.

Videokeratography in conductive keratoplasty.

PURPOSE: We used EyeSys videokeratography to evaluate corneal shape changes induced by conductive keratoplasty, a procedure that utilizes radio frequency energy to alter corneal shape to correct hyperopia. METHODS: Follow-up data were available for 19 eyes (out of 24 eyes of 13 patients). Preoperative spherical hyperopia ranged from +0.75 to +3.25 D with astigmatism <0.75 D. Manifest refractive spherical equivalent refraction (MRSE), uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), topographical parameter predicted corneal acuity (PCA), corneal uniformity index (CU Index), regular astigmatism, total astigmatism, average simulated keratometry (Avg Sim K), effective refractive power, and asphericity were measured preoperatively and at 6 and 12 months postoperatively. RESULTS: Twelve months postoperatively, mean PCA, CU Index, and BSCVA were maintained at preoperative levels. Mean UCVA (LogMAR) improved from 0.53+/-0.21 to 0.10+/-0.19 (P<.05) with a mean MRSE change from +1.62+/-0.76 D to -0.06+/-0.84 D (P<.05) from preoperative to 12 months postoperative. Mean asphericity increased +0.044+/-0.24 D (P>.05), mean Avg Sim K increased 1.88+/-0.72 D (P<.05), mean effective refractive power increased 1.71+/-0.79 D (P<.05), mean cylinder (cycloplegic refraction) increased 0.19+/-0.36 D (P<.05), mean regular astigmatism increased 0.25+/-0.49 D (P>.05), and mean irregular astigmatism decreased 0.01+/-0.13 D (P>.05) from preoperative to 12 months after conductive keratoplasty. CONCLUSIONS: Avg Sim K and effective refractive power changes support the refractive results; 12-month postoperative maintenance of BSCVA, PCA, and CU Index suggest the procedure is safe. Conductive keratoplasty induced a slight regular astigmatism in some eyes, which decreased with time. The increase in mean corneal asphericity indicated possible induction of central and peripheral cornea changes.