RegisterSign in
ViewPDF
- Access throughyour institution
Survey of Ophthalmology
Volume 57, Issue 4,
July–August 2012
, Pages 317-336
Abstract
All optic nerve pathologies, including the glaucomas and disorders such as non-arteritic ischemic optic neuropathy, affect the appearance of the optic nerve head. Morphological examination of the optic nerve head in a qualitative and quantitative manner is therefore clinically mandatory. With the advent of modern imaging modalities such as confocal scanning laser tomography and optical coherence tomography, new diagnostic avenues have opened up to further refine the examination. The new imaging devices are now becoming a major adjunct to the diagnosis and long-term management of optic nerve head pathology; before it is possible to identify an abnormal optic disk, however, it is essential to understand the morphology and measurement of the normal disk. We summarize recent data on the normal morphology and measurement of optic nerve head parameters as assessed by the major imaging modalities now available.
Introduction
Because both the retinal nerve fiber layer and the optic nerve head (ONH) are biological structures, they are not uniform in appearance, but show a remarkable variation within the normal population.70 The appearance of the ONH and retinal nerve fiber layer was appreciated soon after the development of the ophthalmoscope. With the advancement of imaging technology over the last 10 years, imaging modalities such as optical coherence tomography (OCT) and confocal scanning laser ophthalmoscopy (CSLO; Heidelberg Retinal Tomography, HRT) provide additional tools for the routine clinical assessment of the ONH.25, 81, 175 Because these newer technologies allow the determination of quantitative parameters, they can be used not only to visualize the ONH, but also to measure parameters such as the area of the optic disk and cup and their ratio, and thus to assist in the diagnosis and monitoring of diseases affecting the optic nerve. Before one can differentiate between pathology and physiology, however, it is essential to have a firm and thorough understanding of the normal morphology and measurement of ONH parameters. This definition of normal, defined for each imaging modality across many ethnic groups, is an essential aid for all clinicians as well as from the perspective of research.
Past reports have described the morphology and measurement of ONH parameters across numerous populations with varied sample sizes, but as yet this information has not been synthesized into a comprehensive description of the normal variations encountered in clinical ophthalmology. We therefore summarize the international literature accumulated since a previous review in 199964 in order to address the following primary questions: What are the normal measurements of the ONH with respect to ethnic background and the measurement technique applied? and How does the ONH change with increasing age?
Section snippets
Measurement Technique
Planimetry of stereophotographs is considered the gold standard for measuring ONH parameters.11, 40, 59, 126 These stereoscopic image pairs are taken with a parallel shift on either the film or digital single shot camera,117 or alternatively, are a single shot taken with a stereoscopic retinal camera.126 Film images are mounted onto slides and viewed through a stereo-viewer with the aid of a retro-illuminated light box. Digital images, however, are displayed on a computer monitor, where a
Ethnic Variations in Normal Optic Nerve Head Parameters
Normal ONH parameters vary considerably between ethnicities. A rule of thumb may be that the closer to the equator that the patient’s ancestors come from, the larger the optic disk. African Americans may have on average the largest optic disks, followed by Indians, Chinese, and then Europeans. Interestingly, the central corneal thickness follows a reverse direction with the highest corneal thickness measurements found in white patients, followed by Chinese, and the thinnest corneas in Indians
Peripapillary Atrophy
Peripapillary atrophy (PPA) is a clinical finding associated with chorioretinal thinning, photoreceptor loss, and disruption of the retinal pigmented epithelium.103 PPA surrounds the ONH and has been differentiated into a peripheral “alpha” zone and a central “beta” zone.76, 135 Alpha PPA is characterized by an irregular hypo- or hyper-pigmentation adjacent to the retinal margin. Beta PPA is characterized as the unconcealed view of the sclera and sometimes the choroidal vessels, associated with
Associations between Refractive Error and Optic Nerve Head Measurements
Refractive errors were found to have only a minimal effect on measurements of optic nerve parameters among the different modalities.12, 42, 82, 176 Other studies have reported stronger associations between optic nerve parameters and high refractive errors.42, 63, 161 Jonas69 found that the ONH is abnormally large in highly myopic (> –8.0 diopters) eyes, and abnormally small in highly hyperopic eyes (> +4 diopters). Varma173 found a correlation with decreasing disk area with increasing myopia
Influence of Aging on the Optic Nerve Head
Aging leads to a loss of retinal cells at a rate of about 0.3% per year of life, as shown for retinal photoreceptors and retinal pigment epithelium cells123, 124 as well as for the number of retinal ganglion cell axons or optic nerve axons.27, 75 Out of an original population of about 1.4 million axons at birth, white patients lose about 5,000 per year of life. These histomorphometrically shown age-related changes prompt one to assume age-related changes in the appearance of the ONH. It would
Summary
Measurements of ONH parameters obtained from HRT, OCT, and planimetry of stereophotographs are not directly comparable, with a suggestion that HRT generally provides the smallest measures, followed by planimetry and with OCT providing the largest measurements. Planimetry is still considered the gold standard when measuring ONH parameters; however, the magnification correction formulae were developed for planimetry of 35-mm film photographs and are not suitable to use for digital images. The
Method of Literature Search
A search of the PubMed database was conducted in June 2011 with the following search words: planimetry, HRT, Heidelberg Retinal Tomography, OCT, Optical Coherence Tomography, optic disc, optic disk, optic nerve head, optic nerve, normal and morphology. The search was limited to publications written in English, featuring human participants and covered the years 2000–2011. A similar search was performed of the Medline database and the Cochrane Library database to ensure no relevant publications
Disclosure
The authors reported no proprietary or commercial interest in any product mentioned or concept discussed in this article.
References (191)
- C.K. Leung et al.Retinal nerve fiber layer imaging with spectral-domain optical coherence tomography a study on diagnostic agreement with Heidelberg Retinal Tomograph
Ophthalmology
(2010)
- O.J. Knight et al.Comparison of retinal nerve fiber layer measurements using time domain and spectral domain optical coherent tomography
Ophthalmology
(2009)
- B.E. Klein et al.Quantitation of optic disc cupping
Ophthalmology
(1985)
- J.B. Jonas et al.Ophthalmoscopic evaluation of the optic nerve head(Video) Retinal Nerve Fiber Layer Thickness and Optic Nerve Head Parameters in Pediatric Ophthalmology
Surv Ophthalmol
(1999)
- J.B. JonasOptic disk size correlated with refractive error
Am J Ophthalmol
(2005)
- G.J. Jaffe et al.Optical coherence tomography to detect and manage retinal disease and glaucoma
Am J Ophthalmol
(2004)
- N. Itai et al.Comparison of optic disc topography measured by retinal thickness analyzer with measurement by Heidelberg Retina Tomograph II
Jpn J Ophthalmol
(2003)
- M.K. Ikram et al.Comparing ophthalmoscopy, slide viewing, and semiautomated systems in optic disc morphometry
Ophthalmology
(2002)
- S.C. Huynh et al.Macular and nerve fiber layer thickness in amblyopia: the Sydney Childhood Eye Study
Ophthalmology
(2009)
- E.M. Hoffmann et al.Optic disk size and glaucoma
Surv Ophthalmol
(2007)
See AlsoContact Information for Metro Hospital & Heart Institute|Best multispecialist hospital in Delhi NcrPrevalence and Antibiotic Susceptibility Patterns of Methicillin Resistant Staphylococcus Aureus in Patients Attending the Laquintinie Hospital Douala, Cameroon5 Best Bachelors Degrees In Health SciencesPros and Cons of Information Technology
Am J Ophthalmol
(1999)
Ophthalmology
(2006)
Am J Ophthalmol
(2006)
Am J Ophthalmol
(2003)
Ophthalmology
(2005)
Ophthalmology
(2008)
Ophthalmology
(2009)
Ophthalmology
(1985)
Ophthalmology
(2010)
Laser scanning tomography of optic discs of the normal Japanese population in a population-based setting
Ophthalmology
(2009)
The normal optic nerve head on Heidelberg Retina Tomograph II
Indian J Ophthalmol
(2003)
Comparison of HRT-3 glaucoma probability score and subjective stereophotograph assessment for prediction of progression in glaucoma
Invest Ophthalmol Vis Sci
(2008)
Usefulness of optical coherence tomography parameters of the optic disc and the retinal nerve fiber layer to differentiate glaucomatous, ocular hypertensive, and normal eyes
J Glaucoma
(2007)
Agreement in assessing cup-to-disc ratio measurement among stereoscopic optic nerve head photographs, HRT II, and Stratus OCT
J Glaucoma
(2006)
Neural rim characteristics of healthy South Indians: the Chennai Glaucoma Study
Invest Ophthalmol Vis Sci
(2008)
Correction of optic disc measurements on fundus photographs
Graefes Arch Clin Exp Ophthalmol
(1992)
Improvements on Littmann’s method of determining the size of retinal features by fundus photography
Graefes Arch Clin Exp Ophthalmol
(1994)
Evaluating the optic disc and retinal nerve fiber layer in glaucoma. I: Clinical examination and photographic methods
Semin Ophthalmol
(2000)
Imaging of the optic disc and retinal nerve fiber layer: the effects of age, optic disc area, refractive error, and gender
J Opt Soc Am A Opt Image Sci Vis
(2002)
Influence of optic disc size on neuroretinal rim shape in healthy eyes
J Glaucoma
(2000)
Laser scanning tomography and stereophotogrammetry in three-dimensional optic disc analysis
Graefes Arch Clin Exp Ophthalmol
(1993)
Development of the standard reference plane for the Heidelberg retina tomograph
Graefes Arch Clin Exp Ophthalmol
(2000)
Relationship between central corneal thickness and parameters of optic nerve head topography in healthy subjects
Eur J Ophthalmol
(2008)
Discrimination between normal and glaucomatous eyes using Stratus optical coherence tomography in Taiwan Chinese subjects
Graefes Arch Clin Exp Ophthalmol
(2005)
Spectral domain optical coherence tomography and glaucoma. Int Ophthalmol
Clin
(2008)
Racial differences in optic nerve head parameters
Arch Ophthalmol
(1989)
Comparison of glaucomatous parameters in normal, ocular hypertensive and glaucomatous eyes using optical coherence tomography 3000
Korean J Ophthalmol
(2005)
The effect of optic disc diameter on vertical cup to disc ratio percentiles in a population based cohort: the Blue Mountains Eye Study
Br J Ophthalmol
(2004)
Optic disc topography of normal Indian eyes: an assessment using optical coherence tomography
Indian J Ophthalmol
(2008)
Optic disc tomography and perimetry in controls, glaucoma suspects, and early and established glaucomas
Optom Vis Sci
(2007)
Effect of glaucomatous damage on repeatability of confocal scanning laser ophthalmoscope, scanning laser polarimetry, and optical coherence tomography
Invest Ophthalmol Vis Sci
(2007)
Correlations between retinal nerve fiber layer and visual field in eyes with nonarteritic anterior ischemic optic neuropathy
Am J Ophthalmol
(2007)
Aging of the optic nerve
Arch Ophthalmol
(1980)
Assessment of cup-to-disc ratio with slit-lamp funduscopy, Heidelberg Retina Tomography II, and stereoscopic photos
Eur J Ophthalmol
(2009)
Assessment of optic nerve head topographic parameters with a confocal scanning laser ophthalmoscope
Clin Experiment Ophthalmol
(2004)
Optical coherence tomography in the eyes of normal children
Arch Ophthalmol
(2009)
Comparability of cup and disk diameters measured from nonstereoscopic digital and stereoscopic film images
Am J Ophthalmol
(2006)
Discriminating between normal and glaucoma-damaged eyes with the Heidelberg Retina Tomograph 3
Ophthalmology
(2008)
Diagnostic ability of Heidelberg Retina Tomograph 3 classifications: glaucoma probability score versus Moorfields regression analysis
Ophthalmology
(2007)
Measurement of optic disc size: equivalence of methods to correct for ocular magnification
Br J Ophthalmol
(1998)
Cited by (16)
- Optic Nerve Head Development in Healthy Infants and Children Using Handheld Spectral-Domain Optical Coherence Tomography
2016, Ophthalmology
In this study, we did not compare either measures derived from funduscopy or from digital fundus photography with handheld SD OCT results. Samarawickrama et al40 compared digital planimetry results with table-mounted OCT results in 333 children 6.4 to 6.5 years of age and found that “OCT produced consistently smaller linear and area measures than digital planimetry,” also noting that “digital planimetry may be more sensitive than OCT in detecting small, physiologically normal optic cups and hence small cup/disc ratios.” However, Dai et al41 observed that 2-dimensional measurements of the optic disc with fundus imaging can lead to underestimates of horizontal and vertical disc measurements.
To determine feasibility of optic nerve head (ONH) imaging and to characterize ONH development in full-term infants without sedation using handheld spectral-domain optical coherence tomography (SD OCT).
(Video) Cup-to-disc ratio: getting it right | OT Skills GuideProspective cross-sectional study.
Three hundred fifty-two children aged between 1 day and 13 years.
All participants were imaged using handheld SD OCT without sedation during a single scan session. The percentage of successful scans was calculated. Interexaminer reproducibility and differences between right and left eyes were assessed using intraclass correlation coefficients (ICCs). Images were analyzed using ImageJ software. The developmental trajectories over time for ONH parameters were calculated using fractional polynomial modelling.
Disc and cup diameter (expressed as distance in micrometers and visual angle in degrees), cup depth, Bruch's membrane opening–minimum rim width (BMO-MRW), retinal thickness, and retinal nerve fiber layer (RNFL; 1700 μm and 6° from the disc center).
On average, 70% of participants were imaged successfully. Interexaminer reliability was excellent (ICC, >0.89) for diametric and retinal thickness parameters. Right and left eyes were similar for diametric measurements (ICC, >0.79), but more variable for nasal BMO-MRW, RNFL, and retinal thickness. The mean disc and cup diameter increase by 30% and 40%, respectively, between birth and 13 years of age when expressed as a distance measure, but remained constant (at 5°–5.5° and 2°, respectively) when expressed as a visual angle with reference to the eye nodal point. The peripapillary temporal RNFL demonstrated a marked initial decrease of nearly 35% between birth and approximately 18 months of age. This was followed by a slow increase up to 12years of age when measured at 1700 μm from the disc center, although there was little change when measured at 6° from the disc center.
We demonstrated feasibility of handheld SD OCT imaging of the ONH in full-term infants and children without anaesthesia or sedation. This is the first invivo handheld SD OCT study to describe the development of ONH parameters during the critical early years of visual maturation. Our results provide a normative database for use in routine practice and further studies of ONH pathologic features.
- Ultra-widefield Imaging of the Peripheral Retinal Vasculature in Normal Subjects
2016, Ophthalmology
However, these methods do not account for peripheral distortion of the UWF images. In addition, the sizes of the landmarks vary from one person to another; thus, such conversion strategies are not accurate.17 The stereographic projection used in this study provides a conformal 2-dimensional image-preserving shape mapped by ray tracing all relevant pixels from a 3-dimensional model.12
To establish the extent of the peripheral retinal vasculature in normal eyes using ultra-widefield (UWF) fluorescein angiography.
Prospective, observational study.
Fifty-nine eyes of 31 normal subjects, stratified by age, with no evidence of ocular disease in either eye by history and ophthalmoscopic examination.
Ultra-widefield fluorescein angiographic images were captured centrally and with peripheral steering using the Optos 200Tx (Optos, Dunfermline, United Kingdom). Images obtained at different gaze angles were montaged and corrected for peripheral distortion using a stereographic projection method to provide a single image for grading of the peripheral edge of the visible vasculature. The border of the vascularized retina was expressed as a radial surface distance from the center of the optic disc. The vascularized area was calculated based on this mean peripheral border position for each quadrant.
Mean distance (mm) from the center of optic disc to the peripheral vascular border.
In normal eyes, the mean radial surface distance from the center of the optic disc to the peripheral edge of the visible vasculature was 20.3±1.4 mm and the mean area of normal perfused retina was 977.0 mm2. There was no significant difference between right and left eyes or between male and female participants. However, the distance to the periphery differed depending on the quadrant, with temporal (22.5±0.9 mm) beinglarger than inferior (20.4±1.7 mm) being larger than superior (19.2±1.5 mm) being larger than nasal (17.4±0.9 mm; P < 0.001) for all interquadrant comparisons. Interestingly, the distances to the perfused vascular border were significantly shorter in older individuals (≥60 years) than in younger subjects.
Ultra-widefield fluorescein angiography is an important tool for studying the extent of peripheral retinal vasculature. With the increasing use of UWF imaging to evaluate and manage patients with retinal vascular disease, the normative data from this study may provide a useful reference when assessing the pathologic significance of findings in the setting of disease.
- Structural characteristics of the optic nerve head influencing human retinal venous pulsations
2016, Experimental Eye Research
Our recently published photoplethysmographic technique allows us to accurately determine the location and amplitude of venous pulsation at varying locations surrounding the human optic nerve (Morgan et al., 2014, 2015a). In this study, we correlate venous pulsation with SD-OCT anatomical parameters to quantitatively and qualitatively study structural characteristics surrounding sites of venous pulsation (Samarawickrama et al., 2012). This study was approved by the Human Research Ethics Committee of The University of Western Australia.
The relationship between structural characteristics of the optic nerve head and venous pulsations in the human eye remain unknown. Using photoplethysmographic techniques we investigated whether properties of the human retinal veins and their surrounding structures influence venous pulsation. 448 locations of venous pulsation were analysed from 26 normal human eyes. Green channel densitometry derived from video recordings of venous pulsations were used to generate a map of venous pulsation amplitudes along retinal veins. Optical coherence tomography was used to perform quantitative measurements of tissue characteristics at sites of high and low amplitude points as well as in a second analysis, at maximal amplitude pulsation sites from superior and inferior halves of the eyes. Structural characteristics measured included venous diameter, distance from pulsation point to cup margin, vessel length from pulsation point to vein exit, tissue thickness overlying vein, optic disc diameter and presence of a proximal arteriovenous crossing. Increasing venous pulsation amplitudes were associated with larger applied ophthalmodynamometry force, increasing venous diameter, and decreasing absolute cup margin distance (all p<0.001). Increasing distance of maximal amplitude pulsation point to cup margin was associated with the presence of a proximal arteriovenous crossing, increasing venous diameter, and decreasing tissue depth (all p≤0.001). Venous diameter and tissue depth alter venous compliance, which is likely to be a major factor determining sites of venous pulsation.
A novel strategy for quantification of panoramic en face optical coherence tomography angiography scan field
2019, Graefe's Archive for Clinical and Experimental Ophthalmology
Evaluation of Optic Nerve Head Parameters and Retinal Nerve Fiber Layer Thickness in Axial Myopia Using SD OCT
2017, Ophthalmology and Therapy
Retinal nerve fiber layer measures and cognitive function in the EPIC-Norfolk cohort study
2016, Investigative Ophthalmology and Visual Science
Recommended articles (6)
Research article
Management of subluxated lens in young patientsArchivos de la Sociedad Española de Oftalmología (English Edition), Volume 88, Issue 3, 2013, pp. 97-101
To evaluate visual outcomes in patients treated for lens subluxation. Secondary objectives are to report best corrected visual acuity (BCVA) in LogMAR and compare the outcomes of patients managed conservatively with those treated surgically.
Retrospective comparison of BCVA in patients under the age of 50 years old with lens subluxation, managed conservatively or surgically.
A total of 49 eyes of 28 patients were included. Demographic characteristics were similar in both groups. Twenty eyes were treated surgically (40.8%) compared to 29 with medical treatment (59.2%). Marfan syndrome (79.6%) was diagnosed in 39 eyes. LogMAR BCVA post intervention was 0.35±0.31 for medical treatment and 0.39±0.32 for the surgical group, with no significant differences (p=0.63). Improvements in LogMAR lines were 2.7±4.2 and 4.11±4.2 (p=0.35), respectively. Two eyes in the surgery group developed ocular hypertension (0.04%), none with retinal detachment.
The final BCVA showed no significant differences in this group of patients. BCVA depends on the visual potential of the rehabilitated eye rather than a specific type of intervention.
Evaluar resultados visuales en pacientes tratados por subluxación del cristalino. Los objetivos secundarios son reportar la agudeza mejor corregida (AVMC) en LogMAR y comparar los resultados de los pacientes manejados de manera conservadora con aquellos manejados quirúrgicamente.
(Video) Interpretation of OCT Optic NerveEstudio retrospectivo comparativo de AVMC en pacientes menores de 50 años con subluxación de cristalino, manejados de manera conservadora con lentes o tratados quirúrgicamente.
49 ojos de 28 pacientes fueron incluidos. Las características demográficas fueron similares en ambos grupos. 20 ojos fueron tratados quirúrgicamente (40,8%) versus 29 con tratamiento médico (59,2%). 39 ojos con diagnóstico de síndrome de Marfán (79,6%). La AVMC LogMAR post intervención de 0,35±0,31 para el tratamiento médico y 0,39±0,32 para el grupo de manejo quirúrgico, sin encontrarse diferencias significativas (p=0,63). Las mejorías en líneas LogMAR fueron respectivamente 2.7±4.2 y 4.11±4.2 (p=0,35). Dos ojos del grupo cirugía evolucionaron con hipertensión ocular (0,04%), ninguno con DR.
La AVMC final no presentó diferencias significativas en este grupo de pacientes, dependiendo del potencial visual del ojo rehabilitado más que de un tipo específico de intervención.
Research article
Optic Disc Margin Anatomic Features in Myopic Eyes with Glaucoma with Spectral-Domain OCTOphthalmology, Volume 125, Issue 12, 2018, pp. 1886-1897
To investigate optic disc margin anatomic features in myopic eyes with open-angle glaucoma (OAG) using spectral-domain (SD) OCT.
Cross-sectional study.
Two hundred four eyes of 102 participants with OAG and 106 eyes of 53 participants without glaucoma with axial length of 24 mm or more.
Radial SD OCT B-scans centered on the optic discs were acquired in each eye, and the SD OCT data were colocalized with the optic disc stereophotographs. Optic disc margin anatomic features were evaluated as (1) SD OCT structure coinciding with the disc margin identified in the stereophotograph, (2) border tissue configuration, and (3) presence of Bruch’s membrane overhang, and their frequency was computed in each clock-hour position. Further, paired eyes of myopic participants with OAG were divided into eyes with better or worse visual field defect (VFD), according to the mean deviation of the Humphrey visual field test, and associated factors were compared.
Spectral-domain OCT structures coinciding with the visible optic disc margin in stereophotographs.
In myopic eyes with OAG, mean axial length was 25.96±1.07 mm and mean deviation was –8.87±7.78 dB. In approximately 90% of the participants, anterior scleral opening (ASO) coincided with the temporal disc margin and Bruch’s membrane opening (BMO) with the nasal disc margin. Border tissue configuration was externally oblique in the temporal region and internally oblique in the nasal region of the optic disc. Bruch’s membrane overhang was observed in a relatively small percentage of eyes. The same pattern of disc margin anatomic features was observed in the myopic eyes without glaucoma. The myopic optic disc was shaped by the temporal shifting of the BMO from the ASO, and the extent of shifting was expressed as the width of γ zone parapapillary atrophy (PPA). The greater γ zone PPA width was associated significantly with the worse VFD between paired eyes.
The myopic eyes with OAG exhibited characteristic optic disc margin anatomic features that was considered to be derived from myopic deformation of the eye. The greater γ zone PPA width may increase susceptibility to the glaucomatous stress.
Research article
Reduced Free Communication of the Subarachnoid Space Within the Optic Canal in the HumanAmerican Journal of Ophthalmology, Volume 183, 2017, pp. 164-165
Research article
The use of 30° test in nontrauma patients suspected of elevated intracranial pressureThe American Journal of Emergency Medicine, Volume 33, Issue 4, 2015, p. 595
Research article
Optimising subjective anterior eye grading precisionContact Lens and Anterior Eye, Volume 43, Issue 5, 2020, pp. 489-492
To establish the optimum grading increment which ensured parity between practitioners while maximising clinical precision.
Second year optometry students (n = 127, 19.5 ± 1.4 years, 55 % female) and qualified eye care practitioners (n = 61, 40.2 ± 14.8 years, 52 % female) had 30 s to grade each of bulbar, limbal and palpebral hyperaemia of the upper lid of 4 patients imaged live with a digital slit lamp under 16× magnification, diffuse illumination, with the image projected on a screen. The patients were presented in a randomised sequence 3 times in succession, during which the graders used the Efron printed grading scale once to the nearest 0.1 increment, once to nearest 0.5 increment and once to the nearest integer grade in a randomised order. Graders were masked to their previous responses.
For most grading conditions less than 20 % of clinicians showed a ≤0.1 difference in grade from the mean. In contrast, more than 50 % of the student graders and 40 % of experienced graders showed a difference in grade from the mean within 0.5 for all conditions under measurement. Student precision in grading was better with both 0.1 and 0.5 grading increments than grading to the nearest unit, except for limbal hyperaemia where they performed more accurately with 0.5 unit increment grading. Limbal grading precision was not affected by grading step increment for experienced practitioners, but 0.1 and 0.5 grading increments were both better than the 1.0 grading increment for bulbar hyperaemia and the 0.1 grading increment was better than the 0.5 grading increment and both were better than the 1.0 grading increment for palpebral hyperaemia.
Although narrower interval scales maximise the ability to detect smaller clinical changes, the grading increment should not exceed one standard deviation of the discrepancy between measurements. Therefore, 0.5 grading increments are recommended for subjective anterior eye physiology grading (limbal, bulbar and palpebral redness).
Research article
Stickler syndrome. Epidemiology of retinal detachmentArchivos de la Sociedad Española de Oftalmología (English Edition), Volume 90, Issue 6, 2015, pp. 264-268
A review was performed on all patients with Stickler syndrome that had been treated in our Center since it was diagnosed, in order to evaluate the risk of suffering a retinal detachment (RD).
A total of 14 patients, diagnosed by clinical criteria, were included. The following variables were evaluated: age, gender, ocular background, follow-up, initial and final visual acuity (VA), optical prescription, prophylactic treatment, surgery and techniques performed. The risk age to suffer a RD, as well as cataracts, was determined by using the Kaplan–Meier survival curve analysis.
From a total of 5 men and 9 women, the median initial VA was 0.35, which was the same as the final VA. The median optical prescription was −9.5 D myopia. The median of follow-up was 7 years. Ocular background was 4 RD cases and 2 Lasik surgeries. The operations performed were 8 RD, 12 cataract, 2 glaucoma, 2 macular hole, and one endotropia. The median age of RD was 20 years and cataract 34 years. As regards surgical tecnique, 4 scleral buckle cases, and 4 scleral buckle+pars plana vitrectomy cases were formed. The prophylactic treatments performed were: one scleral buckle case, 4 endolaser photocoagulation, and one cryotherapy. Two of which presented with RD.
In the series presented, retinal detachment in Stickler syndrome mainly occurs in the second decade of life, with cataracts mainly developing in the fourth decade.
Revisión de todos los pacientes con síndrome de Stickler que se han tratado en nuestro centro desde su descripción, para valorar el riesgo de padecer desprendimiento de la retina (DR).
Un total de 14 pacientes, diagnosticados por criterios clínicos, en los que hemos valorado las siguientes variables: sexo, edad, antecedentes oculares, seguimiento, agudeza visual (AV) inicial y final, refracción, tratamiento profiláctico, cirugías y la técnica empleada. Mediante el análisis de curva de supervivencia de Kaplan-Meier hemos determinado la edad riesgo de padecer DR así como cataratas.
En total fueron 5 hombres y 9 mujeres. La AV mediana inicial fue de 0,35, igual que la AV final. Refracción mediana de −9,5 dioptrías de miopía. La mediana de seguimiento de 7 años. Los antecedentes oculares fueron 4 DR y 2 Lasik. Las cirugías que realizamos han sido 8 DR, 12 cataratas, 2 glaucomas, 2 agujeros maculares y una endotropía. La mediana de años en el que sucedió el DR fue de 20 y las cataratas a los 34. La técnica quirúrgica utilizada en 4 casos ha sido el cerclaje y en los otros 4 restantes cerclaje con vitrectomía vía pars plana. Un total de 6 ojos han sido tratados profilácticamente: uno con cerclaje, 4 con fotocoagulación láser y otro con criocoagulación; de estos, 2 han presentado DR.
En nuestra serie, el DR en esta dolencia se desarrolla mayoritariamente en la segunda década de la vida. Las cataratas, fundamentalmente en la cuarta década.
Crown copyright © 2012 Published by Elsevier Inc. All rights reserved.
FAQs
What size is the normal optic nerve head? ›
The normal optic nerve head diameter varies in size from 1.2 to 2.5mm. There is some inconsistency in the literature as to what cutoffs to use for a small or large disc, but in general a disc can be considered small if ≤ 1.2 mm and large if ≥ 1.8 mm.
How do you evaluate the optic nerve of the head? ›Overview. Examination of the optic nerve head (ONH) is essential for the diagnosis of glaucoma and assessment of its progression. Slit-lamp biomicroscopy with a handheld lens is the best method of ONH examination since it provides good stereopsis and magnification.
What is optic nerve head elevation? ›Optic nerve head elevation is an important physical examination finding in the evaluation of patients with visual disturbances or vision loss. It may be associated with optic disc edema or not (pseudoedema).
What is normal optic nerve? ›A normal optic nerve head (ONH) usually is round or oval, mildly elevated and pink in color, with a centralized depression known as the cup. The horizontal diameter of a typical optic nerve is approximately 1.5mm.
What is the normal range of RNFL thickness? ›Average RNFL thickness indicates a patient's overall RNFL health. The mean value for RNFL thickness in the general population is 92.9 +/- 9.4 microns. Typically, a normal, nonglaucomatous eye has an RNFL thickness of 80 microns or greater.
What is the normal cup-to-disc ratio? ›The normal cup to disc ratio (the diameter of the cup divided by the diameter of the whole nerve head or disc) is about 1/3 or 0.3. There is some normal variation here, with some people having almost no cup (thus having 1/10 or 0.1), and others having 4/5ths or 0.8 as a cup to disc ratio.
How is optic nerve measured? ›Ultrasound examination was performed in both eyes to measure the optic nerve sheath diameters 3 mm behind the globe. These measurements were compared with control data obtained from 102 children who attended the radiology department for unrelated renal ultrasound examination.
How is optic nerve damage measured? ›During an MRI to check for optic neuritis, you might receive an injection of a contrast solution to make the optic nerve and other parts of your brain more visible on the images. An MRI is important to determine whether there are damaged areas (lesions) in your brain.
What is suspicious optic nerve? ›A suspicious optic nerve is worrisome for possible swelling, which is known as edema. Swollen optic nerves may be caused by high pressure within the brain (known as papilledema). Papilledema is a medical emergency and may require urgent neuroimaging, lumbar puncture, and hospitalization to determine the cause.
What is optic nerve head? ›The optic nerve head (ONH) is the structure in the posterior ocular fundus that allows the exit of the retinal ganglion cell axons and the entry and exit of the retinal blood vessels.
What is the visual field for papilledema? ›
The most common visual field defects encountered in patients with early or acute papilledema are enlargement of the physiological blind spot, arcuate visual field defects (typically inferonasal), and concentric constriction.
What are signs of optic nerve damage? ›Common symptoms of optic nerve damage include vision distortion, loss of vision, eye redness, and pain when moving the eye. These symptoms may also be present with a variety of other eye conditions, so a proper diagnosis by a qualified medical professional is needed.
What is the normal measurement of the eyes? ›The size of a human adult eye is approximately 24.2 mm (transverse) × 23.7 mm (sagittal) × 22.0–24.8 mm (axial) with no significant difference between sexes and age groups. In the transverse diameter, the eyeball size may vary from 21 mm to 27 mm.
What is the diameter of the optic nerve? ›CONCLUSION. In healthy persons, the ONSD varies from 5.17±1.34 mm to 3.55±0.82 mm in different locations within the intraorbital space.
How wide is the optic nerve? ›The optic nerve head (also known as the optic disc) is approximately 1.5 mm wide and is also associated with a physiological cup that corresponds to a central depression in the optic nerve head.
What is optic nerve head? ›The optic nerve head (ONH) is the structure in the posterior ocular fundus that allows the exit of the retinal ganglion cell axons and the entry and exit of the retinal blood vessels.
What does a small cup-to-disc ratio mean? ›Abstract. Background: A small cup-to-disc (C:D) ratio is an established risk factor for nonarteritic anterior ischemic optic neuropathy. We sought to determine if a small C:D. ratio was present in patients with idiopathic intracranial hypertension (IIH) as a potential risk factor for visual loss in that disorder.