Short wavelength automated perimetry and peripapillary retinal nerve fiber layer in early diabetes

@#<p style="text-align: justify;"><strong>OBJECTIVE:</strong> To investigate the significance of short wavelength automated perimetry (SWAP) in detecting retinal functional impairment in early diabetic patients without retinopathy and with mild non-proliferative diabetic retinopathy (NPDR). <br /><br /> <strong>METHODS:</strong> This is a prospective, cross-sectional study of 37 eyes of early diabetics which were divided into 2 groups: no DR with 18 subjects and mild NPDR with 19. All subjects underwent HBA1C, SWAP, peripapillary RNFL thickness measurement and fundus photo. Visual field indices: MD and PSD as well as average RNFL thickness were compared among the 2 groups. Correlation of MD with RNFL thickness and HBA1C were also analyzed. <br /><br /> <strong>RESULTS:</strong> There was no statistically significant difference in the MD (-4.46 ± 3.03 vs -2.94 ± 2.21; p=0.09), PSD (3.08 ± 1.28 vs 2.69 ± 0.47; p=0.23) and average peripapillary RNFL thickness (98.47 ± 6.89 vs 98.72 ± 11.01; p=0.93) among early diabetics with mild NPDR and no signs of DR. There is no correlation between MD and RNFL thickness in the no DR group (R2=0.017) and the mild DR group (R2=0.000). There was a weak correlation between MD and HBA1C in the no DR group (R2=0.137), while no correlation was seen in the mild NPDR group (R2=0.000). <br /><br /> <strong>CONCLUSION:</strong> SWAP does not appear to be a sensitive measure of worsening retinopathy in older individuals with early diabetes. The usefulness of SWAP and peripapillary RNFL thickness in the early stages of retinopathy are inconclusive.</p>

Safety of intracameral moxifloxacin/dexamethasone fixed-dose formulation on the corneal endothelium in a rabbit model

@#<p style="text-align: justify;"><strong>OBJECTIVE:</strong> To determine the safety of intracamerally injected preservative-free 0.5% moxifloxacin/0.1% dexamethasone fixed-dose combination on the corneal endothelium in a rabbit model and compare it to intracamerally injected preservative-free 0.5% moxifloxacin.</p> <p style="text-align: justify;"><strong>METHODS:</strong> This experimental study included twenty eyes from ten albino rabbits. The eyes were assessed for baseline corneal clarity and anterior chamber (AC) inflammation using slit-lamp biomicroscopy. A specular microscope measured the corneal endothelial cell density (ECC) and corneal thickness (CT). Intracameral injections of 0.1 mL 0.5% moxifloxacin ophthalmic solution were administered to the 10 right eyes (IPFM group) and 0.1 mL of 0.5% moxifloxacin/0.1% dexamethasone fixed-dose preparation were administered to the 10 left eyes (IPFMDex group). In both groups, ECC, CT, corneal clarity, and AC inflammation at Day 1 (one day post-injection) and Day 7 (seven days post-injection) were compared with Day 0 (baseline). The IPFMDex group was also compared with the IPFM group at Days 0, 1, and 7. The endothelial cells of harvested corneas from both groups at Day 1 and 7 were stained with trypan blue and alizarin red, and compared for endothelial cell damage (ECD). Data were analyzed using paired and independent sample t-tests.</p> <p style="text-align: justify;"><strong>RESULTS:</strong> In both the IPFM and IPFMDex groups, ECC and CT at Day 1 (IPFM: ECC p=0.07, CT p=0.76; IPFMDex: ECC p=0.41, CT p=0.94) and Day 7 (IPFM: ECC p=0.95, CT p=0.28; IPFMDex: ECC p=0.29, CT p=0.34) were not different from Day 0 (baseline). No significant difference in ECC, CT, and ECD were found between the IPFM and IPFMDex groups at Day 1 (ECC p=0.82, CT p=0.36, ECD p=0.96) and Day 7 (ECC p=0.95, CT p=0.22, ECD p=0.61). Throughout the study, the cornea in both groups were clear and showed no signs of AC inflammation.</p> <p style="text-align: justify;"><strong>CONCLUSION:</strong> Intracameral injection of preservative-free moxifloxacin/dexamethasone fixed-dose formulation was safe on the rabbit corneal endothelium and was no different from preservative-free moxifloxacin.</p>

Correlation between average retinal nerve fiber layer thickness and rim area of the spectral-domain OCT with the Humphrey visual field index in eyes with glaucoma

@#<p style="text-align: justify;"><strong>OBJECTIVE:</strong> To determine the correlation between the average retinal nerve fiber layer (RNFL) thickness and optic nerve head rim area (RA) measured with a spectral-domain optical coherence tomography (OCT) with the visual field index (VFI) using the Humphrey Visual Field Analyzer in glaucoma patients.<br /><strong>METHODS:</strong> Eighty-five consecutive patients diagnosed with glaucoma underwent spectral-domain OCT of the optic disc and Humphrey perimetry. A glaucoma specialist confirmed the presence of glaucomatous optic neuropathy based on findings in the optic nerve head photographs, OCT measurements of the RNFL and optic disc, and standard automated perimetry. The correlation of the average RNFL thickness and rim area with the VFI was determined using the Spearman's correlation coefficient analysis.<br /><strong>RESULTS:</strong> A total of 121 glaucomatous eyes of 85 patients were included in the study. There were 47 males and 38 females, ages ranging from 12 to 94 years. The average RNFL thickness, RA, and VFI were 67.9 ± 12.3 ?m, 0.65 ± 0.3 mm2, and 56 ± 32%, respectively. The average RNFL thickness (r = 0.35) showed a stronger positive correlation with VFI than RA (r = 0.15), but the difference was not statistically significant.<br /><strong>CONCLUSION:</strong> The average RNFL thickness and rim area of the spectral-domain OCT demonstrated a positive correlation with the VFI of the Humphrey Visual Field Analyzer. The OCT parameters, exemplified by average RNFL and RA, were not good indicators for VFI.</p>

Understanding structure and function in glaucoma

OBJECTIVE: Glaucomatous optic neuropathy (GON), defined as definitive damage to the optic-nerve head (ONH) and retinal-nerve-fiber layer (RNFL), involves structural changes in the ONH and RNFL and functional losses in the central visual field. Due to the unique anatomic distribution of the nerve fibers as they enter the ONH, there are specific changes in the ONH correlated with specific findings in the visual-field characteristic of GON. The evaluation of these changes is discussed. METHODS: There are qualitative and quantitative methods in the structural examination of the ONH and RNFL, and quantitative techniques in the functional assessment of the central visual field. They are correlated to one another their strengths and limitations are discussed. RESULTS: Clinical evaluation of the ONH and RNFL consists of five basic rules: (1) identify the limits of the optic disc and determine its size, (2) identify the s of the neuroretinal rim, (3) examine the RNFL, (4) examine the region for parapapillary atrophy, and (5) look for retinal and optic-disc hemorrhages. These steps are simple to use and comprise a portion of the comprehensive eye evaluation. Without proper documentation of the changes in glaucoma progression may be missed. Computer-based digital-imaging technology exemplified by the HRT II, GDx, OCT, provides fast, reproducible, objective measurements of the ONH and RNFL, allowing for more precise diagnosis and monitoring of glaucoma. These changes have good correlation to functional assessments exemplified by the standard automated perimetry (SAP) and the selective perimetry (FDT, SWAP). Typical glaucomatous visu field defects include nasal step, paracentral scotoma, and arcuate defects which follow the RNFL pattern. Progression of these defects is monitored over time and needs to be differentiated from long-term fluctuation. CONCLUSION: The clinician should perform both structural and functional assessments to diagnose and monitor glaucoma. Both examinations provide complimentary information and each has its own place in the clinical care of glaucoma patients. The newer imaging devices and selective perimetry augment the diagnostic armamentarium of the clinician and should, therefore, be used appropriately.

Biphasic tricalcium phosphate spheres with muscle resection in primary enucleation

Purpose: To combine the advantage of porosity and biocompatibility of Biphasic Tricalcium Phosphate implant with Muscle Resection Methodology: Non-randomized, uncontrolled clinical case series Results: No migration or extrusion was observed. With improved muscle resection, socket and prosthesis mobility were noted. (Author)