Application of retinal nerves fiber layer examination--GDx in patients with multiple sclerosis

PURPOSE: The purpose of our study is to evaluate retinal fiber layer thickness with scanning polarymetry laser (GDx), in patients suffering from SM with or without optic nerve symptoms. Multiple sclerosis proceeds to neurodegenerative changes and commonly appears with retrobulbar optic nerve damage. Examination of retinal nerves fiber layer examination with scanning laser polarymetry (GDx) enables to perform quantitative evaluation of retinal nerves fiber layer thickness within the area around the optic nerve disc. It finds application in diagnosis and monitoring of glaucoma, however its usefulness as a tool evaluating optic nerve in multiple sclerosis, has not been proved yet. MATERIALS AND METHODS: Subjects diagnosed with multiple sclerosis (SM) were divided into 2 groups. First group was comprised of subjects, who suffered from at least one episode of retrobulbar neuritis, in at least one eye. Second group was made up of 8 subjects with no history of retrobulbar neuritis. Retinal nerves fiber layer thickness was measured with scanning polarymetry laser (GDx). RESULTS: Symptoms of retinal nerves fiber layer damage, were discovered with GDx significantly more common in first group (70% vs 18.75% accordingly). CONCLUSIONS: Moreover, we stated that evaluation with scanning polarymetry laser might be precious method in discovering retinal nerves fiber layer damage in the course of multiple sclerosis. Presence of defects in retinal nerves fiber layer in patients suffering from multiple sclerosis with no history of retrobulbar neuritis may suggest subclinical damage of optic nerve.     

激光共聚焦扫描检眼镜在青光眼早期诊断中的应用

激光共聚焦扫描检眼镜 (confocal scanning laser ophthalm oscopy,CSLO)是近年来出现的一种新型眼底检查设备。它可对视盘及其周围结构的形态进行客观、定量、三维地测量 ,对眼底血管及血流进行检查和测定。目前已成为眼科诊断的重要辅助设备。本文即对 CSL O在青光眼中的一部分应用做一综述。1　海德堡视网膜断层扫描的应用青光眼损害是不可逆的 ,青光眼的早期诊断是改善其预后的一个重要途径。而青光眼尤其是开角型青光眼首先发生眼底形态学改变 ,当视功能损害超过 4 0 %时才出现视野缺损。因此通过对视盘形态学测量和动态观察可提高…     

Bilateral visual field defects with optic disc drusen and secondary open angle glaucoma with PEX--clinical correlation with the HRA

BACKGROUND: Arcuate visual field defects are a typical sign of glaucomatous damage. Elevated intraocular pressure in combination with pseudoexfoliation syndrome (PSX) manifests the diagnosis glaucoma. Beyond this state, in microdiscs with optic disc drusen, the exact classification of the visual field defects is crucial. CASE REPORT: A 57-year-old male with pseudoexfoliation glaucoma was referred because of progressive glaucomatous visual field defects. The visual acuity was right 20/40 and left 20/25. Maximum intraocular pressure was 36 mm Hg. A simple optic nerve atrophy was diagnosed superonasally. The optic disc size was OD 2.24 mm(2) and OS 1.89 mm(2) (HRT I). An Ultrasound B-mode scan demonstrated the diagnosis of optic disc drusen. Over a follow-up of 1 year, a growth tendency was observed, especially in the superonasal quadrant. The mulberry-shaped surface of the drusen was visualized with infrared reflection images (HRA II, 830 nm). Confocal scanning laser ophthalmoscopy (HRA II, excitation 488 nm, 500 nm notch filter) showed an increased intrapapapillary autofluorescence (> 50 % papillary area: OD 1.67 mm(2), OS 1.26 mm(2)). This technique could detect drusen in areas that looked normal in classical retinoscopy. CONCLUSION: The differential diagnosis of arcuate scotomas includes simple optic nerve atrophy and glaucomatous optic nerve atrophy. Optic disc drusen in glaucoma eyes can obscure the main cause of progressive visual field loss. Superficial optic disc drusen can be measured planimetrically over the years. An adequate reduction of intraocular pressure should be realized in these eyes.     

A case of optic nerve drusen associated with Grönblad-Strandberg syndrome

PURPOSE: We report a rare case of optic nerve drusen associated with Gr?nblad-Strandberg syndrome. CASE: The patient was a 29-year-old woman who had pseudoxanthoma elasticum on her neck. OBSERVATIONS: On eye examination, there were no abnormal findings in the anterior segment or ocular media. Ophthalmoscopic examination revealed milky white granular lesions on the optic nerve disc, and angioid streaks around the disc in both eyes. Orbital computerized tomography(CT), B-scan echography and photography with a fluorescein angiography filter identified the granular lesions as optic nerve drusen. With a scanning laser ophthalmoscope(SLO), poorly-visible drusen buried below the nerve head could be detected. The optic nerve drusen could be seen more clearly by infrared laser than by helium-neon laser. CONCLUSIONS: SLO using infrared laser is useful for evaluation of superficial and buried drusen.     

Optic nerve assessment: a clinical endpoint of optic neuropathy

Objective, quantitative, and reproducible methods of optic nerve assessment need to be utilized during research that measures the capability of pharmacological agents to prevent or decrease the rate of progressive ganglion cell atrophy occurring with glaucoma. Confocal scanning laser ophthalmoscopy has recently been developed, and offers objective, quantitative, and three-dimensional evaluation of the optic nerve head and peripapillary retina. This article reviews the use, application, and parameters of one such instrument, the Heidelberg Retina Tomograph (HRT). Although HRT offers several methods to evaluate changes in optic nerve topography, these applications are still continually evolving. Therefore, confocal scanning laser ophthalmoscopy may be particularly useful for assessing the neuroprotective effect of new medications for glaucoma.     

Preperimetric glaucoma diagnosis by confocal scanning laser tomography of the optic disc

AIM: To evaluate the ability of confocal scanning laser tomography of the optic nerve head to detect glaucomatous optic nerve damage in ocular hypertensive eyes without visual field defects. METHODS: The study included 50 normal subjects, 61 glaucoma patients with glaucomatous changes in the optic disc and visual field, and 102 "preperimetric" patients with increased intraocular pressure, normal visual fields, and glaucomatous appearance of the optic disc as evaluated on colour stereo optic disc photographs. For all individuals, confocal scanning laser tomographs of the optic nerve head were taken using the Heidelberg retina tomograph (HRT; software 2.01). RESULTS: Almost all investigated HRT variables varied significantly (p < 0.05) between the normal eyes and preperimetric glaucoma eyes with pronounced overlap between the two study groups. Corresponding to the overlap, sensitivity and specificity values were relatively low when HRT variables were taken to differentiate between normal and preperimetric glaucoma eyes. At a given specificity of 95% highest sensitivities were found for the variables "rim area in the superior disc sector" (24.8%), "nerve fibre layer thickness in the inferior disc sector" (26.5%), and "rim volume in the superior disc sector" (25.5%). A multivariate approach increased sensitivity to 42.2% at a given specificity of 95%. For the glaucoma group highest sensitivity values were reached by rim volume in the superior disc sector (73.8%) and rim area (72.1%); the multivariate approach reached 83.6%. CONCLUSIONS: Owing to pronounced overlapping between the groups, confocal scanning laser tomography of the optic nerve head has relatively low diagnostic power to differentiate between normal eyes and preperimetric glaucoma eyes. One of the reasons may be the biological interindividual variability of quantitative optic disc variables.     

Evaluating the optic disc and retinal nerve fiber layer in glaucoma. II: Optical image analysis

Glaucoma is a widespread, blindness-causing disease that is characterized in part by specific and sometimes subtle changes in optic disc and retinal nerve fiber layer topography. Several recently developed computer-based optical imaging techniques allow objective evaluation of the optic disc and retinal nerve fiber layer. These techniques use different optical properties and different properties of the retina to provide micron scale measurements of many aspects of optic disc and retinal nerve fiber layer structure. This article describes and evaluates 3 of these techniques: confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography.     

Evaluating the Optic Disc and Retinal Nerve Fiber Layer in Glaucoma II: Optical Image Analysis

Glaucoma is a widespread, blindness-causing disease that is characterized in part by specific and sometimes subtle changes in optic disc and retinal nerve fiber layer topography. Several recently developed computer-based optical imaging techniques allow objective evaluation of the optic disc and retinal nerve fiber layer. These techniques use different optical properties and different properties of the retina to provide micron scale measurements of many aspects of optic disc and retinal nerve fiber layer structure. This article describes and evaluates 3 of these techniques: confocal scanning laser ophthalmoscopy, scanning laser polarimetry, and optical coherence tomography     

Optic disc morphometry correlated with confocal laser scanning Doppler flowmetry measurements in normal-pressure glaucoma

PURPOSE: To examine the relationship between morphologic optic disc parameters and hemodynamic parameters as measured by confocal laser scanning Doppler flowmetry in patients with normal-pressure glaucoma. METHODS: The study included 91 eyes of 54 patients with normal-pressure glaucoma (mean age: 57.7 +/- 9.8 years), and 136 eyes of 77 age-adjusted normal controls. Color stereo optic disc photographs were morphometrically examined, and confocal laser scanning flowmetry (Heidelberg Retinal Flowmeter) in the neuroretinal rim inside of the optic disc, and in the retina close to the temporal and nasal border of the optic nerve head was performed. RESULTS: Mean confocal laser scanning flowmetric measurements in the neuroretinal rim, temporal parapapillary retina, and nasal parapapillary retina were significantly (P<0.03) lower in the normal-pressure glaucoma group than in the age-adjusted control group. Correspondingly, mean confocal laser scanning flowmetric measurements within the neuroretinal rim decreased significantly, with relatively low correlation coefficients, decreasing neuroretinal rim area (P = 0.016; correlation coefficient r2 = 0.026), and increasing mean visual field defect (P = 0.011; r2 = 0.029). Measurements were statistically independent of alpha zone (P = 0.38; r2 = 0.004) and beta zone (P = 0.57; r2 = 0.002) of parapapillary atrophy. CONCLUSIONS: Confocal laser scanning flowmetric measurements within the neuroretinal rim were lower in eyes with normal-pressure glaucoma than in age-matched normal eyes. Confocal laser scanning flowmetric measurements decrease with increasing glaucomatous optic nerve damage. There is, however, a marked variability preventing a clear relationship between stage of glaucoma and decrease in confocal laser scanning flowmetric measurements. The correlation between parapapillary atrophy and confocal laser scanning flowmetric measurements is not statistically significant in normal-pressure glaucoma.     

Agreement of measurement of parapapillary atrophy with confocal scanning laser ophthalmoscopy and planimetry of photographs

PURPOSE: To evaluate whether parapapillary atrophy can be measured interactively using confocal scanning laser ophthalmoscopy. METHODS: For 36 patients with open-angle glaucoma or suspected of having glaucoma, confocal scanning laser ophthalmoscopy of the optic nerve head was performed using the Heidelberg Retina Tomograph (HRT; Heidelberg Engineering, Heidelberg, Germany). Alpha and beta zones of parapapillary atrophy were plotted independently by two examiners on HRT images before and after reviewing optic disc photographs. These data were compared with planimetric measurements obtained from analyzing the disc photographs. RESULTS: Before viewing the disc photographs, assessment using the HRT images correlated better with the beta zone than alpha zone planimetric measurements. If the HRT images were evaluated while simultaneously viewing disc photographs, correlation coefficients increased for both examiners 1 and 2. Interobserver and intraobserver reliability were 0.431 and 0.802, respectively, for alpha zone, and 0.882 and 0.948, respectively, for beta zone. CONCLUSION: Parapapillary atrophy can be estimated with confocal scanning laser ophthalmoscopy. Correlation with planimetric measurements is best if conventional optic disc photographs are simultaneously viewed. Intraobserver and interobserver reliability are higher for beta zone than for alpha zone.     

Comparative study of deep lying drusen of the papilla with the scanning laser ophthalmoscope and fundus camera]

We examined four patients with the suspected diagnosis of optic disc drusen by scanning laser ophthalmoscopy (SLO) and fundus photography. In all four cases the autofluorescence that distinguishes optic disc drusen was observed with the SLO, but not with the fundus camera. Three of the four examined patients, children or adolescents, were spared further diagnostic procedures to clarify the underlying cause of the swollen optic disc.     

Discriminant analysis models for early detection of glaucomatous optic disc changes

AIM: To evaluate and compare four different mathematical formulas for the early detection of morphometric optic nerve head changes in chronic open angle glaucoma. METHODS: The optic nerve heads of 161 patients with perimetrically defined glaucomatous optic nerve damage and of 194 normal subjects were examined by confocal laser scanning tomography. Using four formulas of linear discriminant analysis and the optic cup shape measure as the single optic disc variable, the predictive power of each of these methods was examined to differentiate between the normal eyes and the glaucoma eyes. RESULTS: The highest predictive power had an optic disc sector based formula, in particular in eyes with medium and large optic discs. This optic disc sector based formula was the one with the best agreement with the other formulas examined. It achieved a better predictability than any single optic disc variable evaluated. CONCLUSIONS: Combining quantitative optic disc variables by discriminant analysis functions, the predictive power of semiautomatic quantitative optic nerve head evaluation can be improved by providing the ophthalmologist with a diagnostic score for the detection of glaucomatous optic nerve damage. Because of the pattern of glaucomatous neuroretinal rim loss, an optic disc sector based discriminant formula may have a higher diagnostic precision than other formulas in detecting early glaucomatous damage.     

Diagnostic laser in glaucoma: scanning laser polarimetry (GDx VCC) and confocal scanning laser tomography (HRT)

Automated structural measurements of retinal nerve fibers and optic nerve head are possible with new lasers providing objective and reproductible data for analysis. Scanning laser polarimetry (GDx VCC), based on retardation of polarized light, assesses peripapillary nerve fiber layer thickness. Confocal scanning laser tomography yields precise topographic maps of the optic disc and peripapillary retina. The advantages, applications for glaucoma detection, both in a screening setting as well as for monitoring progression, limitations and pitfalls need to be well known and results should be analyzed with clinical data.     

Is the ISNT rule violated in early primary open-angle glaucoma--a scanning laser tomography study

AIMS: To evaluate the relevance of the ISNT rule with reference to the optic nerve head, in differentiating normal and early glaucoma eyes and neuroretinal rim (NRR) area ratios as measures of glaucomatous optic neuropathy by confocal scanning laser ophthalmoscopy (Heidelberg retina tomography (HRT) II). METHODS: The study included 136 control eyes and 63 eyes of early primary open-angle glaucoma. Each patient underwent a complete ophthalmic examination, HRT II (software 2.01) and achromatic automated perimetry using the Humphrey field analyzer Full threshold program 30-2 or 24-2. Topographic HRT parameters (disc area and rim area) were compared between the groups. To assess the statistical significance of differences between the study groups, the Student's t-test was used. RESULTS: The ISNT rule was applicable in 71% of normal eyes and 68% of early glaucoma eyes. The superior to inferior area ratio was 0.96+/-0.01 in the normal group and 0.90+/-0.02 in the glaucoma group. There was a loss of approximately a quarter of the NRR in the inferotemporal and superotemporal quadrants. The inferonasal sector showed the least loss of NRR (4.34%). CONCLUSION: The inferior NRR is marginally wider than the superior NRR in about 2/3 of normal eyes, but could not be clinically appreciated in many of these. The characteristic configuration of a normal optic disc with the rim width being greatest in the inferior disc region followed by the superior disc region was maintained even in most patients with early glaucoma.     

Fundus Autofluorescence in Optic Disc Drusen: Comparison of Confocal Scanning Laser Ophthalmoscope and Standard Fundus Camera

We have evaluated fundus autofluorescence (FAF) imaging in optic disc drusen (ODD). After a detailed ophthalmological examination, 28 eyes of 16 patients were evaluated by FAF imaging using a confocal scanning laser ophthalmoscope and a standard fundus camera. ODD displayed bright nodular autofluorescence. Increased FAF was observed using both the scanning laser ophthalmoscope and the fundus camera. However, high quality images with precise localization of hyaline material at the optic nerve head were only possible using FAF imaging with the confocal scanning laser ophthalmoscope. FAF images obtained using the fundus camera revealed only brightness at the optic nerve head without any detail except when maximum flash intensity was used. We conclude that FAF imaging may be used as a non-invasive, safe and rapid ancillary test for the confirmation of the diagnosis of drusen of the optic disc.     

Assessment of optic disc anatomy and nerve fiber layer thickness in ocular hypertensive subjects with normal short-wavelength automated perimetry

PURPOSE: To compare optic disc topography and nerve fiber layer thickness in ocular hypertensive eyes and normal subjects. DESIGN: Prospective, case-controlled study. PARTICIPANTS AND CONTROLS: One eye in each of 20 normal and 27 ocular hypertensive patients was enrolled. METHODS: Consecutive normal and ocular hypertensive patients were enrolled. Each patient underwent complete ophthalmic examination, achromatic automated perimetry, short-wavelength automated perimetry, confocal scanning laser ophthalmoscopy, confocal scanning laser polarimetry, and optical coherence tomography. The intraocular pressure was 21 mmHg or less for normal subjects and at least 25 mmHg on two separate occasions in ocular hypertensive eyes. Structural parameters were compared between the two groups. Eyes with evidence of glaucomatous optic neuropathy, achromatic visual field loss, or evidence of focal visual field injury during short-wavelength automated perimetry were excluded. MAIN OUTCOME MEASURES: Optic nerve head topography and nerve fiber layer thickness. RESULTS: The three imaging technologies could not detect differences in optic disc or nerve fiber layer anatomy between the two groups. Ocular hypertensive eyes had a greater corrected pattern standard deviation than normal eyes during short-wavelength automated perimetry (P = 0.04). CONCLUSIONS: Ocular hypertensive eyes with normal achromatic automated perimetry and short-wavelength automated perimetry could not be distinguished from normal subjects with confocal scanning laser ophthalmoscopy, confocal scanning laser polarimetry, and optical coherence tomography.     

Interocular differences in optic disc topographic parameters in normal subjects

PURPOSE: To test the interocular differences in optic disc topography in normal subjects by means of confocal scanning laser ophthalmoscopy. METHODS: Topographic measurements of the optic disc were evaluated by means of confocal scanning laser ophthalmoscopy (Heidelberg Retina Tomograph) in 314 eyes of 157 healthy volunteers. The examination was started randomly either with the right eye or the left eye. Differences between right and left eyes in disc area, cup area, cup volume, cup/disc area ratio, rim area, rim volume, maximum cup depth, cup shape measure, retinal nerve fiber layer thickness, and retinal nerve fiber cross section area for 360 degrees and for the temporal and nasal regions of the optic nerve head were evaluated by means of Student t-test. The same parameters were assessed in a subgroup of 80 elderly (age> 50 years) healthy subjects. Holm's sequentially rejective method was used for significance correction of multiple comparisons. RESULTS: Significant interocular differences in the average retinal nerve fiber layer thickness (p = 0.0010) and retinal nerve fiber layer cross section area (p = 0.0036) were found, with the right eye showing, on the average, lower values.The left eye showed a larger retinal nerve fiber layer thickness in 94 subjects (59.87%) and a larger retinal nerve fiber cross section area in 101 subjects (64. 33%). In the temporal optic disc area there were no statistically significant differences in topometric data (p> 0.05). In the nasal area, significant interocular differences in the retinal nerve fiber layer thickness (p = 0.0002) and retinal nerve fiber layer cross section area (p = 0.0003) were found. Similar results were found when the group of subjects older than 50 years was considered. CONCLUSIONS: This study demonstrates systematic interocular differences in optic disc topometric data. Such a finding, be it due to methodological or biological reasons, should be taken in consideration in clinical trials.     

Correlation between photopic negative response and retinal nerve fiber layer thickness and optic disc topography in glaucomatous eyes

PURPOSE: To investigate whether there is a significant correlation between the photopic negative response (PhNR) of the electroretinogram (ERG) and retinal nerve fiber layer thickness and optic disc topography in glaucomatous eyes. METHODS: Ninety-nine eyes of 53 patients with open-angle glaucoma (OAG) and 30 eyes of 28 normal volunteers were studied. Photopic ERGs were elicited by red stimuli (644 nm, 1600 cd/m(2)) on a blue background (470 nm, 40 cd/m(2)). The mean deviation (MD) of the visual field was obtained by static visual field analyses. The topography of the optic nerve head was determined by confocal scanning laser ophthalmoscopy. The retinal nerve fiber layer thickness (RNFLT) around the optic nerve head was measured with a scanning laser polarimeter. RESULTS: The amplitude of the PhNR and the PhNR/b-wave ratio decreased with an increase in visual field defects. The logarithmic values of the PhNR amplitude and PhNR/b-wave amplitude ratio were significantly correlated with the MD better than the linear values. The PhNR amplitude and PhNR/b-wave amplitude ratio were significantly correlated with the RNFLT and the rim area of the optic disc and with the cup/disc area ratio. These correlations were higher when expressed linearly than when stated logarithmically. The sensitivity and specificity were 77% and 90% for the PhNR amplitude and 70% and 87% for the PhNR/b-wave amplitude ratio when the optimal cutoff values were used. Although the a-wave amplitude correlated with the MD, the a-wave amplitudes of most of the patients fell within the normal range. The correlation between the b-wave amplitude and MD was not significant. CONCLUSIONS: The PhNR amplitudes correlate with the decrease in function and morphology of retinal neurons in eyes with OAG. The linear relationship between the PhNR and the structural parameters indicates that inner retinal function declines proportionately with neural loss in eyes with glaucoma.     

Evolution of an Astrocytic Hamartoma of the Optic Nerve Head in a Patient with Retinitis Pigmentosa - Photographic Documentation over 2 Years of Follow-Up

Aim

To report photographically the evolution of an astrocytic hamartoma of the left optic nerve head over a 2-year follow-up in a patient with retinitis pigmentosa.

Methods

A 14-year-old boy was seen in the medical retina clinic with a 3-year history of night blindness. Best corrected visual acuity was 6/18 in both eyes. Colour vision was normal in both eyes and confrontation fields showed peripheral constriction. Fundus examination revealed bone spicule pigmentary changes at the retinal mid periphery typical of retinitis pigmentosa and superficial globules at the margins of both optic nerve heads. Electrodiagnostic tests confirmed moderately severe rod cone dystrophy with macular involvement bilaterally.

Results

Two years later, the ocular examination was unchanged except for the appearance of the optic nerve head lesion in the left eye. There was an increase in the size of the lesion which was diagnosed as an astrocytic hamartoma. Further investigations were recommended to exclude neurofibromatosis and tuberous sclerosis.

Conclusion

Astrocytic hamartomas of the optic nerve head and optic nerve head drusen have both been described in patients with retinitis pigmentosa. They can be a diagnostic dilemma although drusen are more common (10%). To differentiate these two entities it is very important to document any growth during the follow-up period which is suggestive of astrocytic hamartoma rather than optic disc drusen.Key Words: Astrocytic hamartoma, Optic disc drusen, Retinitis pigmentosa     

Diagnosis and follow-up in glaucoma patients using the Heidelberg retina tomograph

The development of laser scanning tomography in the late 1980s enabled the possibility of an exact three-dimensional biomorphorphometry of the optic nerve head. This technique is designed for 3D measurement of the topography of the optic disc with high accuracy and reproducibility. With the development of the Heidelberg retina tomograph with highly advanced and user-friendly software, a quick examination is possible.Currently the instrument is already used on a routine basis in the ophthalmological practice. It has been shown that glaucomatous changes of the optic disc can be detected using laser scanning tomography before perimetric deterioration occurs. Therefore this technique is crucial in the follow-up of glaucoma patients.