Francisco M. Honrubia

Can frequency-doubling technology and short-wavelength automated perimetries detect visual field defects before standard automated perimetry in patients with preperimetric glaucoma?

PurposeTo assess the ability of frequency-doubling technology (FDT) perimetry and short-wavelength automated perimetry (SWAP) to detect glaucomatous damage in preperimetric glaucoma subjects. ParticipantsTwo hundred seventy-eight eyes of 278 subjects categorized as normal eyes [n=98; intraocular pressure <20 mm Hg, normal optic disc appearance, and standard automated perimetry (SAP)]; preperimetric glaucoma eyes (n=109; normal SAP and retinal nerve fiber layer defects or localized optic disc notching and thinning); and glaucoma patients (n=71; intraocular pressure >21 mm Hg, optic disc compatible with glaucoma, and abnormal SAP). MethodsThe preperimetric glaucoma group underwent at least 2 reliable full-threshold 24-2 Humphrey SAPs, full-threshold C-20 FDT, full-threshold 24-2 SWAP, optic disc topography using the Heidelberg Retina Tomograph II, laser polarimetry using the GDx VCC, and Optical Coherence Tomography (Zeiss Stratus OCT 3000). Receiver operating characteristic curves were plotted for the main Heidelberg Retina Tomograph, Optical Coherence Tomography, and GDx VCC parameters for the normal and glaucoma patients. The area under the receiver operating characteristic curve was used to determine the parameters indicating glaucomatous damage in the optic disc or retinal nerve fiber layer, which were used to establish additional subgroups of patients with preperimetric glaucoma. FDT and SWAP sensitivities were calculated for the patient subsets with structural damage and normal SAP. ResultsAt least 20% of the patients with preperimetric glaucoma demonstrated functional losses in FDT and SWAP. The more severe the structural damage, the greater the sensitivity for detecting glaucomatous visual field losses. ConclusionsFDT and SWAP detect functional losses in cases of suspected glaucoma before glaucomatous losses detected by SAP.

Sub‐clinical atrophy of the retinal nerve fibre layer in multiple sclerosis

Acta Ophthalmol. 2010: 88: 748–752

Predictive value of short-wavelength automated perimetry: A 3-year follow-up study

PURPOSE To determine whether structural changes in the retinal nerve fiber layer (RNFL) and functional abnormalities in short-wavelength automated perimetry (SWAP) can predict the onset of functional losses in standard automated perimetry patients suspected of having glaucoma. DESIGN Prospective observational case series. PARTICIPANTS A total of 160 eyes of ocular hypertensive subjects (intraocular pressure greater than 21 mmHg and normal standard automated perimetry) were included in the study. INTERVENTIONS The subjects underwent RNFL photographic evaluation and SWAP. Standard automated perimetries were repeated after 3 years to evaluate glaucomatous losses. MAIN OUTCOME MEASURES Onset of glaucomatous defects in conventional automated perimetry after 3 years of follow-up, with or without prior glaucomatous defects in RNFL and SWAP. RESULTS At the beginning of the study, 77 eyes showed RNFL losses (48%), and 58 eyes showed abnormalities in SWAP (36%). After the 3-year follow-up period, 14 of 77 eyes with RNFL losses had standard automated perimetry abnormalities (predicting sensitivity 93%), whereas 11 of 58 eyes with abnormal SWAP had standard automated perimetry losses (73% sensitivity). CONCLUSIONS RNFL and SWAP losses are signs of early glaucomatous damage and can predict functional losses in standard automated perimetry.

Diagnostic ability of the Heidelberg retina tomograph, optical coherence tomograph, and scanning laser polarimeter in open-angle glaucoma.

PurposeTo compare the ability to discriminate between healthy and glaucomatous eyes of different criteria based on parameters from 3 optical imaging devices: Heidelberg retina tomograph (HRT-II), optical coherence tomograph (Stratus OCT 3000) and scanning laser polarimeter (GDx VCC). DesignCross-sectional study. ParticipantsA total of 139 eyes from 139 subjects were enrolled in this study and classified into 66 healthy subjects and 73 glaucomatous patients according to intraocular pressure and standard automated perimetry. MethodsAll the subjects underwent complete ophthalmic examination, including HRT-II, OCT, and GDx VCC evaluations. Main Outcome MeasuresSeveral parameters were obtained by these techniques and 8 diagnostic criteria were assessed. Receiver operating characteristics curves were plotted and compared among them, and sensitivity for specificity higher than 95% was calculated for every criterion. Agreement among the 3 technologies was assessed by means of Venn diagrams. ResultsThe best criteria discriminating between healthy and glaucomatous eyes were Moorfields regression analysis out of the 95% confidence interval (HRT-II), OCT retinal nerve fiber layer average thickness <77 μm, and nerve fiber indicator >37 (GDx VCC) with sensitivities of 85%, 66%, and 48%, with specificity higher than 95%. Sixty-six patients out of 73 were correctly identified by at least 1 of the devices and 30 were detected by the 3 of them. ConclusionsStructural criteria assessed by the optical imaging devices evaluated in this study are useful to discriminate glaucomatous damage.

Magnification characteristics of the Optical Coherence Tomograph STRATUS OCT 3000

Purpose:  To evaluate the magnification characteristics of an Optical Coherence Tomograph (STRATUS OCT 3000) used to measure optic disc size.

Optimum criteria for short-wavelength automated perimetry

OBJECTIVE To determine the optimum perimetric criteria for short-wavelength automated perimetry on the basis of probabilistic maps that best discriminate between normal and glaucoma. DESIGN Comparative cross-sectional study. PARTICIPANTS Ninety-five glaucomatous eyes and 128 normal eyes were included in the study. INTERVENTIONS The subjects underwent retinal nerve fiber layer photographic evaluation and short-wavelength automated perimetry. MAIN OUTCOME MEASURES A probabilistic map of differential points for short-wavelength automated perimetry was elaborated, and the number of altered points was calculated for each visual field and level of significance (95%, 98%, 99%, and 99.5%). RESULTS The presence of a cluster of four or more points outside 95% normal probability limit showed a good combination of sensitivity and specificity. At deeper levels, P: < 1% and P: < 0.5%, the best combination is achieved with three points outside the normal probability limits. CONCLUSIONS The optimum criterion to define glaucomatous abnormalities in short-wavelength automated perimetry is the presence of a cluster of four points lower than P: < 5% or a cluster of three points lower than P: < 1%.

Correlation of functional and structural measurements in eyes suspected of having glaucoma.

PURPOSE This study was conducted to determine the correlation between structural changes in the retinal nerve fiber layer (RNFL) and functional loss detected on short-wavelength automated perimetry (SWAP) in a population of patients with suspected glaucoma. METHODS With a selection criteria of intraocular pressure (IOP) more than 21 mmHg and normal results of conventional automated perimetry, 49 eyes of 49 patients with ocular hypertension were enrolled in the study. The SWAP was performed with a modified Humphrey field analyzer, and visual field indexes (mean deviation [MD], corrected pattern standard deviation [CPSD]) were calculated. Semiquantitative RNFL scores were given separately to diffuse and localized defects of the RNFL. RESULTS The MD increased significantly with higher diffuse and total RNFL scores, with good correlation coefficients. A weak correlation was found between CPSD and diffuse, total, and localized RNFL scores. CONCLUSION Diffuse RNFL loss are associated with abnormalities in visual field indexes (MD), whereas focal structural damage showed no correlation with visual field loss.

Comparison of the Efficacy and Safety of Contact versus Peribulbar Anaesthesia in Combined Eye Surgery

Purpose: To compare the combined levels of comfort, the presence of complications and the results of phacotrabeculectomy surgery obtained with 2 different forms of anaesthesia: topical contact anaesthesia and peribulbar injected anaesthesia. Procedures: In total, 120 consecutive patients undergoing phacotrabeculectomy were randomly assigned to each anaesthesia group. The patients were asked to rate their pain level on a 5-point scale at 3 time points during the procedure. Early and late surgical complications and clinical parameters of success were evaluated. Results: Administration of contact anaesthesia was clearly associated with less pain than injection of peribulbar anaesthesia. The amount of pain or discomfort experienced during or following surgery did not differ between the patient groups. No long-term differences in the tensional results were observed between the groups of the study. Conclusion: The application of contact anaesthesia in the phacotrabeculectomy procedure provides a level of comfort and safety that is comparable to that achieved with peribulbar anaesthesia. Likewise, patients that received contact anaesthesia were as comfortable as patients that received the peribulbar injection of anaesthesia, not only during the immediate postoperative period, but also in terms of their tensional results and their visual acuity in the mid and long term.

Preperimetric glaucoma assessment with scanning laser polarimetry (GDx VCC): analysis of retinal nerve fiber layer by sectors.

PurposeTo evaluate the capability of the GDx VCC nerve fiber analyzer to detect preperimetric glaucoma across 12 retinal nerve fiber layer (RNFL) peripapillary sectors. MethodsData were obtained in a cross-sectional, hospital clinic-based study; 699 eyes from 699 glaucoma suspects were enrolled in this protocol. All subjects underwent ophthalmologic examination, static automated perimetry [Humphrey 24-2 Swedish interactive threshold algorithm (SITA) Standard], optic nerve stereoscopic photographs, red-free digital RNFL photographs and GDx VCC examination. Group S included 283 normal eyes and 39 preperimetric glaucoma eyes with RNFL superior or diffuse defects in the fiber layer photographs. Group I included 324 normal subjects and 24 with preperimetric glaucoma eyes with RNFL inferior or diffuse defects in fiber layer photographs. ResultsMean values of the area under the curve (AUC) for receiver operating characteristic analysis for inferior average (Inf Avg), temporal-superior-nasal-inferior temporal average (TSNIT Avg), superior average (Sup Avg), and the nerve fiber indicator were significantly less in the eyes with RNFL defects than the control group compared with the AUC for thickness at hour 12 and at hour 6 calculated from the RNFL sector density. The AUC for receiver operating characteristic analysis of the new parameters improved by 12% with respect to the best GDx VCC standard values. ConclusionsOur results confirm that the 12 sector divisions of the GDx VCC have better diagnostic reliability in preperimetric glaucoma, and are able to improve the discrimination capability between normal and early damaged RNFLs.

Subconjunctival Injection of Low Doses of Mitomycin C: Effects on Fibroblast Proliferation

We evaluated the effect of low doses of mitomycin C (MMC) in subconjunctival injection on fibroblast viability. Eighteen rabbits received subconjunctival injections: group 1 was injected with balanced salt solution (BSS), group 2 received MMC 0.025 mg, and group 3 MMC 0.005 mg. Tissue samples were taken 1 h after the injection (conjunctiva, sclera and cornea at 0 and 90 °) and cultured. The average scleral and conjunctival outgrowth in the MMC-treated groups was significantly inferior to the outgrowth of the samples treated with BSS. Subconjunctival injections of MMC (0.025 and 0.005 mg) have an inhibitory effect on conjunctiva at 0 ° and on scleral fibroblast populations.