Reappraisal of the ratio of disc to macula/disc diameter in optic nerve hypoplasia.

The ratio of disc to macula/disc diameter is characteristically increased in eyes with optic nerve hypoplasia. We present the largest reported series of patients with a definitive diagnosis of optic nerve hypoplasia for whom this ratio has been determined. All measurements were made by an independent masked observer. Our results are in accordance with previous reports. A ratio of 2.94 provides a one-tailed upper population limit of 95%. An attempt has been made to correlate optic disc size and visual acuity. In 75% of bilateral cases the eye with the relatively smaller optic disc was found to have a better Snellen visual acuity than the fellow eye. This suggests that additional pathogenic mechanism(s) may have determined the eventual visual outcome in such eyes. Such mechanisms include macular hypoplasia, high refractive error, refractive amblyopia, central scotoma, and optic atrophy.     

A case of amblyopia with contralateral optic nerve hypoplasia

We describe an unusual case of unilateral optic nerve hypoplasia (ONH) in a patient with contralateral anisometropic/strabismic amblyopia. A seven‐year‐old boy presented with visual acuities of 6/12 R and 6/18 L and eccentric fixation in the left eye. Cycloplegic retinoscopy was R +1.50/‐0.50 × 180 and L +5.25 DS. Funduscopy revealed optic nerve hypoplasia of the right eye. The patient fixated with his better‐seeing right eye, despite the optic nerve hypoplasia. His reduced vision may be attributed to optic nerve hypoplasia in the right eye and amblyopia in the left. Although optic nerve hypoplasia can occur with ipsilateral amblyopia, we believe this is the first reported case of unilateral optic nerve hypoplasia in the fellow eye of an amblyopic patient.     

Keeping an Eye on Optic Neuritis Studies in Mainland China

Abstract

Optic nerve hypoplasia is diagnosed by the ophthalmoscopic appearance of the fundus of the eye and by standard magnetic resonance imaging of the brain. The ability to study eyes with optic nerve hypoplasia by magnetic resonance diffusion tensor imaging has improved the evaluation of the optic pathways. The authors report a case of unilateral optic nerve hypoplasia with hypoplasia of the contralateral optic pathway. The entire visual pathway of this patient was examined by magnetic resonance and magnetic resonance diffusion tensor imaging. The images show a decrease of the volume of the optic radiation contralateral to the optic nerve abnormality and also pre- and post-chiasmal abnormalities.     

Aniridia and optic nerve hypoplasia

BACKGROUND: This study evaluates, in patients with aniridia, the prevalence of optic nerve hypoplasia and its association with foveal hypoplasia. METHODS: The medical records of 56 patients with aniridia (31 female, 25 male, mean age 33 years, range 2-74 years) were retrospectively evaluated for optic nerve and foveal hypoplasia. The difference in prevalence of foveal hypoplasia in patients with and without optic nerve hypoplasia was compared using Fisher's exact test. RESULTS: Six of 56 patients, 10.7% (95% CI: 4.8-21.5%), had optic nerve hypoplasia; hypoplasia was found in both eyes of five binocular patients and in one monocular patient. The prevalence of foveal hypoplasia was higher in aniridia patients with optic nerve hypoplasia than in those without (50.0 vs 6.0%); this difference did not achieve statistical significance (P=0.10). CONCLUSIONS: Clinically apparent optic nerve hypoplasia is found in roughly 10% of patients with aniridia and may occur independently or in association with foveal hypoplasia.     

Retinal and optic nerve findings in Goldenhar-Gorlin syndrome

Involvement of the posterior segment of the eye in Goldenhar-Gorlin syndrome is more common than is generally appreciated. We examined seven patients with this syndrome. Abnormalities included diminished visual acuity, tilted optic disc, optic nerve hypoplasia, tortuous retinal vessels, macular hypoplasia and heterotopia, microphthalmia and anophthalmia. In one case, pathologic study showed agenesis of the optic nerve. It is proposed that retinal, optic nerve and craniofacial abnormalities in this condition may reflect an asynchrony in the migration of the neural crest cells in the early stages of embryonal development.     

Superior segmental optic nerve hypoplasia: The topless disc syndrome

BackgroundOptic nerve hypoplasia is a well-known congenital maldevelopment presenting with an abnormally small optic nerve head occupying the central aspect of a normally sized chorioscleral canal. Characteristically, the optic nerve head is surrounded by scleral anlage with a “double ring sign.” Less commonly appreciated, however, is the fact that optic nerve hypoplasia may be sectorial rather than total and involving only the superior aspect of the optic disc with corresponding inferior visual field loss.Case ReportA 51-year-old woman presented with a previous diagnosis of idiopathic optic atrophy superiorly in the left eye. Detailed observation revealed that the disc was not atrophic superiorly but actually hypoplastic, and the patient received a conclusive diagnosis of superior segmental optic nerve hypoplasia.ConclusionsIt must be appreciated that optic nerve hypoplasia can also affect solely the superior aspect of the disc with subsequent functional deficits. It is important to differentiate this syndrome from true optic atrophy to ensure proper management.     

Septo-optic dysplasia: a literature review.

BACKGROUND: Septo-optic dysplasia (SOD) is a rare disorder characterized by optic nerve hypoplasia with any combination of absent septum pellucidum and/or pituitary dysfunction. SOD may manifest as strabismus, nystagmus, decreased visual acuity, or visual impairment; as an endocrine dysfunction in isolation; or in addition to mental retardation, cerebral palsy, developmental delay, or delayed growth. METHOD: This article reviews the presenting signs and symptoms of SOD, optic nerve hypoplasia, consequences of an absent septum pellucidum, endocrine findings associated with SOD, SOD diagnosis determination, syndromes associated with SOD, and optometry's role in caring for these patients. It also examines two cases that demonstrate the variety and severity of visual and physical impairments associated with SOD. RESULTS: SOD has a multi-factorial etiology, including insult during pregnancy (e.g., viral infections, gestational diabetes); vascular disruption; or a genetic mutation. Children with SOD may manifest a variety of visual and/or physical symptoms that range from mild to severe. CONCLUSIONS: The associated vision, developmental, neurologic, and endocrine disturbances require early diagnosis and management. Optometrists need to be aware of optic nerve hypoplasia (ONH) and consider this diagnosis in patients with visual acuity loss. A comprehensive eye examination and visual-field assessment should be completed in addition to appropriate referrals for endocrine, developmental, and/or cognitive anomalies.     

Hypoplastic optic nerves studied with B-scan ultrasonography and axial tomography of the optic canals.

Radiologic studies of the optic foramina in cases of optic nerve hypoplasia have been inconsistent, some authors reporting normal foramina, others finding small foramina. The technique of axial tomography of the optic canals has been found more useful in this regard than plain foramen views, and has demonstrated small canals in cases of optic nerve hypoplasia. A case of bilateral hypoplasia is presented in which the discs were one half normal size, the optic nerves measured 2 mm in diameter on B-scan ultrasonography, and the optic canals were about 4 mm in diameter radiographically on the axial tomograms. These measurements are compared with normals of 4 to 4.5 mm for scans of the optic nerve, and a reported average optic canal width of 5.5 mm. A second case of less severe hypoplasia also presented a small ultrasonic nerve pattern of 3.5 mm. With the techniques of ultrasonography and axial tomography, the course of hypoplasic nerves can be followed from the level of the retina to the optic chiasm posteriorly. It is suggested that the optic canal dimensions correspond closely to the size of the optic nerve in cases of hypoplasia. When the nerve is only slightly hypoplastic the radiographic change in foramen or canal dimensions may not be detectable. Reasonably accurate measurements of the nerve may be more easily obtained with ultrasound.     

Monocular nystagmus with sectoral optic nerve hypoplasia in a patient with septo‐optic dysplasia

This case depicts an unusual presentation of septo‐optic dysplasia. A four‐year‐old female presented with monocular nystagmus and temporal optic disc pallor in her left eye. Despite a normal sized optic nerve head, magnetic resonance imaging (MRI) showed a hypoplastic intraorbital and intracranial left optic nerve in the absence of a septum pellucidum. She was subsequently diagnosed with septo‐optic dysplasia with sectoral optic nerve head hypoplasia.     

Pervasive ocular anomalies in posterior microphthalmos.

BACKGROUND: Posterior microphthalmos is a relatively rare condition that has been reported to coexist with several other ophthalmic conditions. However, to the best of the authors' knowledge, there are no previous reports that have found posterior microphthalmos and refractive, binocular, retinal, and neurologic considerations, along with a possible hereditary component. The following report documents the coexistence of posterior microphthalmos with severe hyperopia, esotropia, macular folds, and optic nerve hypoplasia in a pair of siblings. CASE REPORT: A 9-year-old Hispanic girl presented for a comprehensive eye examination. Best-corrected visual acuity (VA) was reduced in both eyes with poorer VA in the right eye. Binocular testing found a small angle constant right esotropia (ET). On dilated fundus examination, a peculiar, elevated, dolphin-shaped folding of the macula was identified, the right eye greater than the left eye, that extended toward an anomalous optic nerve head in both eyes (OU), presumed to be a disc hypoplasia. The patient's brother, who also exhibited severe hyperopia and ET, presented with a similar acuity reduction, a nearly identical folded macular appearance, the right eye more so than the left eye, and a probable optic nerve hypoplasia. Pachymetry, ultrasonography, and ocular coherence tomography imaging of both siblings found thickened corneas in the presence of posterior microphthalmos OU and macular folds affecting only the retina, leaving the choroid and sclera unaffected. CONCLUSIONS: Posterior microphthalmos may exist in the presence of ocular anomalies along with refractive, binocular, retinal, neurologic, and genetic considerations. In this case, optical coherence tomography provided information on the internal morphology of the macular folds, which helped direct the differential diagnosis. The similar presentation among siblings supports a hereditary component that warrants further investigation.     

Value of the Heidelberg Retinal Tomograph in optic nerve hypoplasia

PURPOSE: A case of optic nerve hypoplasia (ONH) is reported to demonstrate the value of the Heidelberg Retinal Tomograph II (HRT) in assisting with the diagnosis. CASE REPORT: An 8-year-old black male was referred to our clinic for evaluation of right esotropia and presumed amblyopia. Best-corrected visual acuities were 20/60 OD (right eye) and 20/25 OS (left eye). Cover test showed constant right esotropia, measuring 10 at distance and 16 at near. A smaller optic nerve head was detected OD with absence of the double ring sign. The findings of HRT were consistent with a diagnosis of unilateral ONH, with a disc area of 1.545 mm OD vs. 2.527 mm OS. DISCUSSION: The clinical features, management, and associations of ONH are discussed. CONCLUSION: HRT is a useful tool to assist in diagnosis of ONH by physically measuring the optic nerve.     

Optical coherence tomography of superior segmental optic hypoplasia

AIM: To describe optical coherence tomography (OCT) images of superior segmental optic hypoplasia (SSOH). METHODS: Five patients (two men and three women, ages 10-45 years) presented with ophthalmoscopic features and visual field defects of SSOH. All affected eyes had good visual acuity and inferior altitudinal or inferonasal visual field loss. The mothers of three patients had type 1 diabetes mellitus. OCT (Humphrey Instrument, CA, USA) was used to evaluate tomographically the optic disc and peripapillary retina of both eyes of each patient. Control data on retinal nerve fibre layer (RNFL) thickness were obtained from 13 normal eyes, one eye each from 13 normal subjects. RESULTS: Seven of 10 eyes in patients had SSOH. Scans in the vertical meridian through the affected optic discs showed a superior defect of the optic disc associated with decreased RNFL thickness and, in some cases, an abnormal extension of a complex of retinal pigment epithelium and choroid over the edge of the lamina cribrosa. Circular scans around the seven optic discs revealed various decreases of peripapillary RNFL thickness in the superior quadrants. Vertical scans through the fovea also showed superior thinning of RNFL. Quantitative assessment of the peripapillary RNFL thickness revealed significantly decreased values in the superior quadrants compared to normal eyes. CONCLUSIONS: OCT provides a new tool for quantitative evaluation of optic nerve hypoplasia as exemplified in this study of SSOH. It can reveal minimal degrees of segmental hypoplasia previously undetected.     

Optical coherence tomographic findings in optic nerve hypoplasia

We investigated a case of unilateral optic nerve hypoplasia using spectral domain optical coherence tomography (SDOCT). Optical coherence tomography was done on both eyes using 5-line Raster scan for the fovea to analyze the retinal nerve fiber layer thickness, inner retinal layer thickness, outer retinal layer thickness, and optic disc cube scan for the disc. Retinal nerve fiber layer thickness, inner retinal layer thickness, and outer retinal layer thickness were manually measured at 21-points of each five lines, and results were compared between both eyes. Retinal nerve fiber layer thickness and inner retinal layer thickness of optic nerve hypoplasia were significantly thinner than the opposite eye, but there was no significant difference in the thickness of the outer retinal layer between both eyes.     

Axial myopia in eyes with optic nerve hypoplasia

Given that abnormal visual experience during post natal development interferes with emmetropization, we proposed that eyes with hypoplastic optic nerves were predisposed to the development of refractive errors. Six of 14 patients with unilateral optic nerve hypoplasia and 5 of 22 patients with bilateral involvement had at least 4 D of myopia. Nine of the 11 patients with asymmetric bilateral involvement had relative myopia in the eye with the more abnormal optic nerve; none of the patients with symmetric bilateral involvement had a significant interocular refractive difference. Analysis of axial length measurements obtained in 10 of the 11 patients with high myopia showed a significant increase in total axial length. The presumed normal eye of patients with unilateral involvement was significantly smaller than the mean value for age-adjusted normals. We suspect that visual input to the central nervous system is one of the feedback signals involved in the regulation of ocular growth.Presented in part at the annual meeting of the Association for Research in Vision and Ophthalmology, Sarasota, Florida, May 4, 1990Correspondence to: A.H. Weiss     

Optic nerve hypoplasia in cholestatic infants: a multiple case study

PURPOSE: To present four infants with optic nerve hypoplasia and cholestasis. METHODS: All patients underwent detailed ophthalmological and hepatological assessment. Their endocrinological and neuroradiological examinations were re-evaluated. RESULTS: All four infants presented with cholestasis and were subsequently found to have optic nerve hypoplasia. One child was blind according to the WHO definition and two had low vision. The fourth child had unilateral optic nerve hypoplasia and was too young to be assessed with optotypes. All four children had central nervous system and/or endocrine dysfunction. However, only one child had septo-optic dysplasia. The longterm outcome of liver disease seemed favourable in all children. CONCLUSION: Early assessment by a paediatric ophthalmologist as well as a multidisciplinary approach is of great importance in cholestatic infants.     

Clinical Feature Analysis of Congenital Optic Nerve Abnormalities

Purpose

We investigated the clinical characteristics and associated ocular and systemic anomalies in young children with congenital optic nerve abnormalities, and evaluated the therapeutic results of treatment for strabismus and amblyopia.

Methods

A retrospective study was conducted using the medical records of patients who were diagnosed with congenital optic nerve abnormalities in our hospital between 1995 and 2004.

Results

This study involved 72 eyes of 51 young children (M?:?F = 25?:?26); 21 of these patients (41.2%) had bilateral abnormalities. The types and percentages of each abnormality were as follows: optic nerve hypoplasia, 47%; optic disc coloboma, 31.4%; morning glory syndrome, 11.8%; and myelinated nerve fiber, 9.8%. The first clinical manifestations noticed by parents were strabismus and decreased visual acuity. Occlusion therapy was carried out in 16 patients, and the visual acuities of two patients were improved by more than two lines of the Early Treatment Diabetic Retinopathy Study visual acuity chart. Accompanying strabismus was found in 70.6% of the patients; 14 patients underwent strabismic surgery, and 10 of these patients (41.2%) maintained a stable angle.

Conclusions

The most common congenital optic nerve abnormality was optic nerve hypoplasia, and the associated systemic abnormalities found were optic nerve hypoplasia and disc coloboma. Patients with congenital optic nerve abnormalities usually have a generally poor visual prognosis, but we emphasize the importance of treatment for associated strabismus and amblyopia.?Jpn J Ophthalmol 2006;50:250–255 © Japanese Ophthalmological Society 2006     

Aicardi syndrome: More than meets the eye

An eight-month-old girl with infantile spasms and apparent blindness had electroencephalographic findings compatible with Aicardi syndrome. In addition to optic nerve hypoplasia, there were multiple congenital retinal malformations in the right eye, including chorioretinal lacunae, anomalous retinal vessels, posterior scleral ectasia, and a peripheral fibrous ridge. Magnetic resonance imaging demonstrated agenesis of the corpus callosum, absence of the septum pellucidum, optic nerve and chiasmal hypoplasia, pachygyria, cortical heterotopias, colpocephaly, and hypoplasia of the cerebellar vermis. This patient illustrates the broad spectrum of cerebroretinal malformations now known to characterize Aicardi syndrome.     

Optic nerve hypoplasia with posterior pituitary ectopia: male predominance and nonassociation with breech delivery

PURPOSE: To determine whether posterior pituitary ectopia in children with optic nerve hypoplasia has a male predominance or an increased incidence of breech delivery. METHOD: Retrospective analysis of 12 children with optic nerve hypoplasia and posterior pituitary ectopia. RESULTS: Eleven of 12 patients with posterior pituitary ectopia were boys. No child had a history of breech delivery. Two children had a history of breech positioning but were delivered by cesarean section. CONCLUSION: Posterior pituitary ectopia with optic nerve hypoplasia shows a strong male predominance but no association with breech delivery.     

Optic nerve hypoplasia: papillary diameter and clinical correlation

Hypoplasia of the optic nerve is often subtle, and reduction in papillary diameter can be difficult to detect during ophthalmoscopic examination. Using a slit-lamp and a posterior fundus contact lens, we evaluated papillary diameter by bringing margins of the light beam to coincide with the limits of the optic nerve head. The method was standardized with 140 presumably normal eyes. Then we studied 17 consecutive eyes showing optic nerve hypoplasia. Hypoplasic discs were separated into two categories: (1) nine cases defined as having "moderate" hypoplasia, in which average disc diameters ranged between -2 and -2.5 standard deviations under the mean normal value; and (2) eight eyes with "severe" hypoplasia, showing average disc diameters less than the normal mean value by 2.5 standard deviations or more. Double peripapillary ring sign and low disc/artery ratio are clues often used in the diagnosis of optic nerve hypoplasia. The incidence of these signs was also evaluated in the hypoplasic discs studies. The double ring sign was present in two of the nine eyes with moderate hypoplasia, and in seven of the eight eyes with severe hypoplasia. Of eight eyes with moderate hypoplasia, only one showed a disc/artery ratio inferior to the mean normal value -2 standard deviations, whereas this ratio was significantly reduced in all cases of severe hypoplasia. These ophthalmoscopic clues therefore appear to be much less valuable than direct measurement of the optic disc for detecting a subtle reduction in disc diameter. This is of particular interest when one considers that all the nine eyes with moderate hypoplasia had alteration in visual function upon presentation.(ABSTRACT TRUNCATED AT 250 WORDS)