Superior segmental optic hypoplasia. A sign of maternal diabetes

Diagnostic value of three-dimensional neuroretinal rim thickness for differentiation of superior segmental optic nerve hypoplasia

Little is known about the diagnostic utility of three-dimensional neuroretinal rim thickness (3D-NRRT) for differentiating patients with superior segmental optic nerve hypoplasia (SSOH) from normal-tension glaucoma (NTG). Since SSOH is defined by characteristic optic nerve head features, investigation of diagnostic usefulness of 3D-NRRT is necessary. In this cross-sectional study, 49 SSOH eyes, 52 NTG eyes, and 41 normal eyes were enrolled. Retinal nerve fiber layer thickness (RNFLT) and 3D-NRRT values, as obtained in the right-eye orientation by optical coherence tomography (OCT), were recorded. On RNFLT clock-hour comparison, the 11-3 clock-hour sectors were significantly thinner for SSOH than for NTG (all P < 0.01). As for 3D-NRRT, whereas the 1 and 2 sectors were significantly thinner for SSOH (P < 0.001, P = 0.004), the 6-11 sectors were significantly thinner for NTG (all P < 0.01). The area under receiver operating characteristic (AUROC) curves of the superior and nasal quadrants of RNFLT (0.838, 0.729) were significantly greater than those of 3D-NRRT (0.518, 0.588; P < 0.001, P = 0.043). However, the AUROCs of the inferior and temporal quadrants were significantly greater for 3D-NRRT (0.728, 0.760) than for RNFLT (0.527, 0.550; P = 0.008, P = 0.019). The appropriate use of 3D-NRRT can be useful in differentiating SSOH from NTG.

Glaucoma Mimickers: A major review of causes, diagnostic evaluation, and recommendations

Background: Glaucoma is characterized by chronic progressive optic neuropathy with corresponding visual field changes, with or without raised intraocular pressure (IOP). When diagnosing glaucoma or monitoring its progression, the examiner has to rely on the appearance of the optic disc, characteristic retinal nerve fiber layer defects, and corresponding visual field defects. However, similar changes and symptoms may be observed in several other disorders of the optic nerve and retina that may mimic glaucoma, often leading to misdiagnosis. Methods and result: The consequences of misdiagnosis not only result in improper treatment that may impact vision but also would negatively affect the overall health, psychological well-being of the patient, and may have considerable economic implications.Conclusion: The current review describes various conditions that mimic glaucoma and the features that help differentiate these conditions from glaucoma.

Usefulness of Optical Coherence Tomography Angiography in the Differential Diagnosis Between Superior Segmental Optic Hypoplasia and Normal-tension Glaucoma

PURPOSE

The differential diagnosis of superior segmental optic hypoplasia (SSOH) and normal-tension glaucoma (NTG) is an issue in the ophthalmologic field. To date, several modalities have been developed to solve this issue; however, no standard methods have been established. Recently, optical coherence tomography angiography (OCTA) has been introduced to better evaluate the volumetric angiography images. Therefore, in this study, we investigated the usefulness of OCTA in differentiating between SSOH and NTG.

MATERIALS AND METHODS

In this retrospective study, we included 26 patients with SSOH who had definite visual field defects and 40 patients with NTG who had only inferior visual field defects. Age, sex, intraocular pressure, refractive error, retinal nerve fiber layer thickness, and visual field defects were compared between the groups. In addition, we analyzed and compared the peripapillary vessel density (VD) measured on OCTA between the groups. The area under the receiver operating characteristic curves were obtained for each parameter.

RESULTS

On Cirrus HD-OCT, the retinal nerve fiber layer in patients with SSOH was thinner in the superonasal segment and thicker in the superotemporal segment compared with patients with NTG. In the analysis of OCTA, the peripapillary VD of the superonasal segment was significantly lower in the SSOH group than in the NTG group, while it was significantly higher in the superotemporal segment in the SSOH group than in the NTG group. The optimal superonasal-to-superotemporal ratio cutoff was 0.8828, with a sensitivity of 95% and specificity of 92.3%, for the diagnosis of SSOH (area under the receiver operating characteristic curve=0.962).

CONCLUSIONS

Our findings suggest that the superonasal-to-superotemporal VD ratio measured on OCTA may be used to distinguish between SSOH and NTG. However, further large-scale studies are required to verify our findings.

Superior segmental optic hypoplasia as a differential diagnosis of glaucoma

Superior segmental optic hypoplasia (SSOH) is a congenital anomaly affecting the optic nerve head and retina. Although the conventional characterization of SSOH emphasizes the relatively superior entrance of the central retinal artery, the pallor of the superior optic disc, a superior peripapillary halo, and thinning of the superior nerve fiber layer, we encounter many cases with rim thinning in the superior nasal region that corresponds to a nerve fiber layer defect and an inferior wedge-shaped visual field defect connecting to the blind spot. However, among Asians, such cases usually lack pallor of the superior optic disc and more resemble glaucomatous optic neuropathy. We found the prevalence of SSOH to be 0.2%/eye and 0.3%/case among Japanese. We also noted that approximately half of all SSOH eyes show visual field changes. SSOH is an important differential diagnosis of glaucoma, especially normal-tension glaucoma, in Asian populations.

Clinical features of superior segmental optic hypoplasia: hospital-based study

PURPOSE

To determine the clinical features of patients diagnosed with superior segmental optic hypoplasia (SSOH) and to quantitatively compare retinal nerve fiber layer (RNFL) thickness in SSOH eyes, to that in normal subjects.

STUDY DESIGN

Retrospective comparative case series.

METHODS

We examined the medical charts of 106 eyes of 59 patients with SSOH and 35 eyes of 35 normal subjects as controls. Forty-four of 59 patients had been examined by spectral-domain optical coherence tomography (SD-OCT). Eyes with SSOH were classified into a definite and a suspect type determined by standard automated perimetry. The definite type had inferior visual field (VF) defects, while the suspect type did not have inferior VF defects. The findings of the SD-OCT images of 35 eyes with SSOH were compared to those of the 35 normal eyes.

RESULTS

Of the 106 eyes with SSOH, 56 (52.8%) were classified as the definite type and 50 (47.2%) as the suspect type. OCT showed that the average of the total RNFL thickness was significantly thinner in the SSOH group than in the normal group (P < 0.001; Mann-Whitney U test). Sectorial analysis demonstrated that the RNFL was thinner than controls in all quadrants (all P < 0.001; Mann-Whitney U test). The comparison of the hourly sectors showed that the RNFL was thinner at 10, 11, 12, 1, 2, 3, 5, and 6 o'clock sectors in the SSOH group than controls.

CONCLUSIONS

Approximately one-half of eyes with SSOH had a detectable VF defect. OCT showed that eyes with SSOH have a thinner RNFL than controls except in 4 o`clock and from 7 o'clock to 9 o'clock.

Incidental branch retinal artery occlusion on optical coherence tomography angiography presenting as segmental optic atrophy in a child: a case report

Background

Retinal artery occlusion is extremely rare in the pediatric population and most patients have risk factors. We report a case of a healthy child with segmental optic atrophy, complicated by incidental branch retinal artery occlusion (BRAO).

Case presentation

A 10-year-old boy who had a history of his mother’s gestational diabetes presented with an inferonasal visual field defect in the left eye. His best-corrected visual acuities were 20/20 in both eyes (OU). Fundoscopic examination revealed segmental pallor of the left optic disc, thinning of the superotemporal rim, a relative superior entrance of the central retinal artery and superior peripapillary scleral halo. Fluorescein angiography showed patchy filling delays in the corresponding disc area without retinal vascular abnormalities. Spectral domain optical coherence tomography (SD OCT) via automated segmentation analysis demonstrated sectoral absence of the ganglion cell layer and retinal nerve fiber layer with thinning of the inner plexiform layer, inner nuclear layer and outer plexiform layer in the corresponding retina. OCT angiography (OCTA) showed focal attenuation of superficial and intermediate/deep capillary plexuses in the corresponding areas. Systemic evaluation was unremarkable. The patient was diagnosed with segmental optic atrophy caused by incidental BRAO.

Conclusions

Retinal vascular occlusions are rare in childhood, and may present as segmental optic atrophy mimicking congenital anomalies. OCTA allows the detection of previous microvascular abnormalities in the chronic phase. To the best of our knowledge, this is the first report of a child with segmental optic atrophy presumably caused by BRAO, which was documented by SD OCT and OCTA in detail.

Congenital anomalies of the optic disc: insights from optical coherence tomography imaging

PURPOSE OF REVIEW

Congenital anomalies of the optic nerve are rare but significant causes of visual dysfunction in children and adults. Accurate diagnosis is dependent on a thorough funduscopic examination, but can be enhanced by imaging information garnered from optical coherence tomography (OCT). We review common congenital optic nerve anomalies, including optic disc pit, optic nerve coloboma, morning glory disc anomaly, and hypoplasia of the optic nerve, review their systemic associations, and discuss insights from OCT imaging.

RECENT FINDINGS

Optic disc pits are a result of a defect in the lamina cribrosa and abnormal vitreomacular adhesions have been shown to cause maculopathy. In patients with optic nerve colobomas, OCT can be instrumental in diagnosing choroidal neovascularization, a rare but visually devastating complication. The pathogenesis of morning glory disc anomaly has been more clearly elucidated by OCT as occurring from a secondary postnatal mesenchymal abnormality rather than only the initial neuroectodermal dysgenesis of the terminal optic stalk in isolation. OCT studies of optic nerve hypoplasia have demonstrated significant thinning of the inner and outer retinal layers of the perifoveal region and thicker layers in the fovea itself, resulting in a foveal hypoplasia-like pathology, that is, significantly correlated to poorer visual outcomes.

SUMMARY

OCT provides detailed in-vivo analysis of these anatomic anomalies and their resulting pathologies, shedding new insights on the pathogenesis, diagnosis, and potential visual outcomes of these conditions in children. Further study employing OCT to elucidate structure-function relationships of congenital optic nerve anomalies will help expand the role of OCT in clinical practice related to diagnosis, prognosis, and management of these entities.

Comparison of the Deep Optic Nerve Structures in Superior Segmental Optic Nerve Hypoplasia and Primary Open-Angle Glaucoma

PURPOSE

The purpose of this study was to characterize the microstructure of the deep optic nerve tissues in eyes with superior segmental optic nerve hypoplasia (SSOH) in comparison with that in primary open-angle glaucoma (POAG).

METHODS

Thirty-five eyes with SSOH, 37 eyes with POAG, and 54 healthy control eyes underwent enhanced depth imaging (EDI) volume scanning of the optic nerve using spectral-domain optical coherence tomography (SD-OCT). POAG patients were matched with SSOH patients in terms of the thickness of the neuroretinal rim and the retinal nerve fiber layer in the superior sector. The lamina cribrosa thickness (LCT) was determined in 3 equidistant planes, and anterior lamina cribrosa surface depth (LCD) was determined in 5 equidistant planes. The measurements were compared between groups, and the areas under the receiver operating characteristic curves (AUC) were obtained for each parameter.

RESULTS

Eyes with SSOH had larger LCT and smaller LCD than POAG eyes at all locations (all P<0.001). The largest LCT was observed at the superior midperiphery in the SSOH group, but at central locations in both the POAG and control groups. The best parameters for discriminating the SSOH from glaucoma and healthy eyes were the superior midperipheral LCT (AUC=0.973) and inferior and inferior midperipheral LCD (AUCs=0.906), respectively.

CONCLUSIONS

The LCT and LCD exhibited characteristic features in eyes with SSOH that were distinctive from those of POAG and healthy eyes. Investigation of the deep optic nerve structure using EDI SD-OCT may be beneficial for differentiating between SSOH and glaucoma, which may help to avoid both overtreatment and undertreatment.

Photopsia and a temporal visual field defect

A 30-year-old woman presented with intermittent photopsia, a temporal visual field defect below the horizontal in her left eye, and flu-like symptoms. Slit-lamp and fundus examinations were unremarkable. Humphrey 30-2 threshold perimetry and 120-point screening visual field demonstrated blind spot enlargement of the left eye and a normal field in the right eye. Fundus autofluorescence, optical coherence tomography of the macula, full-field electroretinogram, electrooculogram, and multifocal electroretinogram were normal. Swept-source optical coherence tomography scan of the left optic nerve showed an intact outer retina, a remarkably thinned nerve fiber layer nasally, and peripapillary vitreous traction. Goldmann kinetic perimetry revealed a sector-shaped dense defect breaking out from the blind spot to the temporal periphery just below the horizontal in the left eye. The patient had nasal hypoplasia of the optic nerve and peripapillary vitreous traction.

The Different Characteristics of Cirrus Optical Coherence Tomography between Superior Segmental Optic Hypoplasia and Normal Tension Glaucoma with Superior Retinal Nerve Fiber Defect

Purpose. To evaluate the different characteristics in superior segmental optic hypoplasia (SSOH) and normal tension glaucoma (NTG) with superior retinal nerve fiber layer (RNFL) defect (NTG-SRD) compared to normal control using cirrus optical coherence tomography (OCT). Methods. SSOH eyes and NTG-SRD eyes were reviewed. The peripapillary RNFL (pRNFL) and ganglion cell inner plexiform layer (GCIPL) of the two groups were compared to age-matched normal controls using cirrus OCT. Results. Included in this study were 31 SSOH eyes, 33 NTG patients, and 49 healthy normal controls. Compared to normal controls, pRNFL thickness in SSOH eyes was thinner except in the inferotemporal to the temporal segment. NTG-SRD eyes had thinner pRNFL except in the nasal to inferonasal segment. Meanwhile, GCIPL thickness in SSOH eyes was thinner in the global and sectoral segment, but not in the superonasal and inferonasal sectors compared to normal controls. NTG-SRD eyes showed thinner GCIPL in all sectors compared to normal controls. In case of comparison between SSOH and NTG-SRD, superonasal sector was thinner in NTG-SRD than in SSOH (P = 0.03). Conclusions. The different distributions of nerve fiber layer were shown in pRNFL and GCIPL between SSOH eyes and NTG-SRD eyes.

Prevalence and risk factors of superior segmental optic hypoplasia in a Korean population: the Korea National Health and Nutrition Examination Survey

BACKGROUND

This study investigated the prevalence and risk factors for superior segmental optic hypoplasia (SSOH) in a Korean population based on the data from the nationwide Korea National Health and Nutrition Examination Survey (KNHANES).

METHODS

We performed a retrospective review of the KNHANES dataset covering January 2012 to December 2012. The study population comprised 5,612 subjects (≥19 years of age) who had participated in a medical interview covering demographic and systemic information, been issued a questionnaire regarding associated SSOH risk factors including gender, age, systemic disease, and family history, and had undergone an ophthalmologic examination. Two masked readers evaluated fundus photography, paying special attention to the presence of SSOH. Associations of risk factors (identified in the medical interview portion) with SSOH prevalence were investigated using multivariate logistic regression analysis.

RESULTS

SSOH was detected in 16 eyes of 14 subjects, or 0.24% of the 5,612 subjects. All 16 eyes showed a corresponding visual-field defect. In multivariate logistic regression analyses, maternal history of diabetes (Odds ratio (OR), 7.666; 95% Confidence interval (CI), 2.601 ~ 22.593, p < 0.001) and paternal history of ischemic heart disease (IHD) (OR, 11.105; CI, 3.361 ~ 36.686, p < 0.001) were associated with increased risk of SSOH.

CONCLUSIONS

This study provides the first representative population-based data on SSOH prevalence in Korea. Additionally, multivariate analyses revealed that a history of maternal diabetes and paternal IHD was the most important factor influencing the prevalence of SSOH.

Congenital anomalies of the optic nerve

Congenital optic nerve head anomalies are a group of structural malformations of the optic nerve head and surrounding tissues, which may cause congenital visual impairment and blindness. Each entity in this group of optic nerve anomalies has individually become more prevalent as our ability to differentiate between them has improved due to better characterization of cases. Access to better medical technology (e.g., neuroimaging and genetic analysis advances in recent years) has helped to expand our knowledge of these abnormalities. However, visual impairment may not be the only problem in these patients, some of these entities will be related to ophthalmologic, neurologic and systemic features that will help the physician to identify and predict possible outcomes in these patients, which sometimes may be life-threatening. Herein we present helpful hints, associations and management (when plausible) for them.

Optic nerve hypoplasia

Optic nerve hypoplasia (ONH) is a congenital anomaly of the optic disc that might result in moderate to severe vision loss in children. With a vast number of cases now being reported, the rarity of ONH is obviously now refuted. The major aspects of ophthalmic evaluation of an infant with possible ONH are visual assessment, fundus examination, and visual electrophysiology. Characteristically, the disc is small, there is a peripapillary double-ring sign, vascular tortuosity, and thinning of the nerve fiber layer. A patient with ONH should be assessed for presence of neurologic, radiologic, and endocrine associations. There may be maternal associations like premature births, fetal alcohol syndrome, maternal diabetes. Systemic associations in the child include endocrine abnormalities, developmental delay, cerebral palsy, and seizures. Besides the hypoplastic optic nerve and chiasm, neuroimaging shows abnormalities in ventricles or white- or gray-matter development, septo-optic dysplasia, hydrocephalus, and corpus callosum abnormalities. There is a greater incidence of clinical neurologic abnormalities in patients with bilateral ONH (65%) than patients with unilateral ONH. We present a review on the available literature on the same to urge caution in our clinical practice when dealing with patients with ONH. Fundus photography, ocular coherence tomography, visual field testing, color vision evaluation, neuroimaging, endocrinology consultation with or without genetic testing are helpful in the diagnosis and management of ONH. (Method of search: MEDLINE, PUBMED).

Prenatal determinants of optic nerve hypoplasia: review of suggested correlates and future focus

Optic nerve hypoplasia (ONH), a congenital malformation characterized by an underdeveloped optic nerve, is a seemingly epidemic cause of childhood blindness and visual impairment with associated lifelong morbidity. Although the prenatal determinants of ONH are unknown, early case reports have led to a longstanding speculation that risky health behaviors (e.g., prenatal use of recreational drugs, alcohol) are a likely culprit. There has yet to be a systematic review of the epidemiology of ONH to assess the common prenatal features that may help focus research efforts in the identification of likely prenatal correlates. A review of the past 50 years of epidemiologic research was conducted to examine the prenatal features linked with ONH and provide direction for future research. There are select prominent prenatal features associated with ONH: young maternal age and primiparity. Commonly implicated prenatal exposures (recreational or pharmaceutical drugs, viral infection, etc.) were rare or uncommon in large cohort studies of ONH and therefore unlikely to be major contributors to ONH. Familial cases and gene mutations are rare. The preponderance of young mothers and primiparity among cases of ONH is striking, although the significance is unclear. Recent research suggests a potential role for prenatal nutrition, weight gain, and factors of deprivation. With the rapidly increasing prevalence of ONH, future research should focus on investigating the relevance of young maternal age and primiparity and exploring the recently suggested etiologic correlates in epidemic clusters of ONH.

The locations of circumpapillary glaucomatous defects seen on frequency-domain OCT scans

PURPOSE

To examine the locations of local glaucomatous damage around the optic disc as seen in the circumpapillary retinal nerve fiber layer (RNFL) on frequency domain optical coherence tomography (fdOCT).

METHODS

Optic disc fdOCT volume scans from 54 healthy control eyes and 114 patient eyes, classified as suspected or mild glaucoma, were analyzed. All patient eyes had 24-2 visual fields (VFs) with mean deviations better than -5.5 dB. By hand-correcting automated segmentation, the RNFL thickness profile was obtained for a circumpapillary circle. RNFL defects were defined as regions where the patient's RNFL thickness fell below the 99% confidence limit of control values. The location of a defect was defined as the point of greatest difference between the patient's thickness and the 99% limit. The locations of major blood vessels (BVs) were marked, and separated into superior-nasal (SN), superior-temporal (ST), inferior-temporal (IT), and inferior-nasal (IN) groups.

RESULTS

Of the 114 patient eyes, 45 exhibited a total of 75 RNFL defects. The locations of these defects clustered around the ST, SN, and IT, but not the IN BVs.

CONCLUSIONS

The absence of defects in the IN region indicates that the locations of local defects are not simply related to either BV location or RNFL thickness. The local defects in the ST and IT regions can be related to arcuate defects seen on 24-2 and 10-2 VFs. However, the defects in the SN region suggest the presence of VF defects that may be overlooked because they fall largely outside the 24-2 test grid.

The optic nerve and visual pathways

We review the clinical examination of the optic disc and assessment of the integrity of the visual pathways: assessment of vision in the infant and child, assessment of disc size and configuration, detection of abnormalities such as cupping or disc swelling and their significance, visual field examination in the child, and the various field defects which result from pathology affecting the visual pathway anywhere along its course. Congenital anomalies of the optic disc, their systemic associations and significance are discussed. We also review the presentation of the visually impaired child, the significance of nystagmus in this context, the differential diagnosis and investigation.

Optic nerve hypoplasia syndrome: a review of the epidemiology and clinical associations

OPINION STATEMENT

BACKGROUND

Optic nerve hypoplasia (ONH) has developed into a leading cause of congenital blindness. The frequently associated features of hypopituitarism and absent septum pellucidum were felt to have embryonic linkage as "septo-optic dysplasia" or "de Morsier's syndrome." More recent studies have suggested these associations are independent of one another. This review provides an assessment of the historical and recent evidence linking neuroradiologic, endocrinologic and developmental morbidity in patients with ONH. The prenatal risk factors, heritability, and genetic mutations associated with ONH are described.

RESULTS

Recognition of the critical association of ONH with hypopituitarism should be attributed to William Hoyt, not Georges de Morsier. De Morsier never described a case of ONH or recognized its association with hypopituitarism or missing septum pellucidum. Hypopituitarism is caused by hypothalamic dysfunction. This, and other more recently identified associations with ONH, such as developmental delay and autism, are independent of septum pellucidum development. Other common neuroradiographic associations such as corpus callosum hypoplasia, gyrus dysplasia, and cortical heterotopia may have prognostic significance. The predominant prenatal risk factors for ONH are primiparity and young maternal age. Presumed risk factors such as prenatal exposure to drugs and alcohol are not supported by scrutiny of the literature. Heritability and identified gene mutations in cases of ONH are rare.

CONCLUSION

Children with ONH require monitoring for many systemic, developmental, and even life-threatening problems independent of the severity of ONH and presence of brain malformations including abnormalities of the septum pellucidum. "Septo-optic dysplasia" and "de Morsier's syndrome" are historically inaccurate and clinically misleading terms.

Superior segmental optic nerve hypoplasia accompanied by progressive normal-tension glaucoma

This is the first case report of a superior segmental optic hypoplasia (SSOH) combined with normal-tension glaucoma accompanied by a progressive glaucomatous visual field defect. A 40-year-old man, incidentally diagnosed as having bilateral SSOH, had disc hemorrhage associated with expansion of the width of a retinal nerve fiber layer defect and deterioration of a visual field defect in the right eye during the follow-up period. His left eye showed a stable visual field. The diurnal variation in intraocular pressure (IOP) showed a higher mean IOP in his right eye compared with his left eye, although both IOPs remained under 21 mmHg.

A case of superior segmental optic hypoplasia accompanied by a glaucomatous optic neuropathy

This is the first case report of a bilateral superior segmental optic hypoplasia (SSOH) accompanied by a glaucomatous optic neuropathy (GON). A 47-year-old man incidentally diagnosed as having bilateral SSOH, simultaneously disclosed glaucomatous optic disc appearances, including enlargements of the cup of the optic nerve heads and a thinning of the infero-temporal neuroretinal rim with laminar dot sign accompanied by a retinal nerve fiber layer (RNFL) local defect of infero-temporal region in the right eye. The visual field examination revealed that the corresponding nasal step, arcuate scotoma and RNFLfield defects in the right eye.

[Incidental finding of bilateral altitudinal visual field defects]

A 28-year-old woman presented with surprisingly asymptomatic bilateral inferior altitudinal visual field defects. Fundoscopy disclosed superior hypoplastic optic discs which was diagnosed as bilateral superior segmental optic hypoplasia. The patient suffered from maternal diabetes and sacral agenesis syndrome, which is also frequently associated with maternal diabetes.

Optic nerve hypoplasia in North America: a re-appraisal of perinatal risk factors

PURPOSE

The purpose of this study is to describe and clarify the birth and prenatal characteristics of a large cohort of children with optic nerve hypoplasia.

METHODS

This is a descriptive report of 204 patients aged

RESULTS

Birth characteristics were unremarkable for birthweight and gestation, but significant for increased frequency of caesarean delivery and fetal and neonatal complications. Young maternal age and primaparity were dominating maternal features. Preterm labour, gestational vaginal bleeding, low maternal weight gain and weight loss during pregnancy were prevalent.

CONCLUSIONS

These findings confirm young maternal age and primaparity as associated risk factors, challenge many other suggested factors such as alcohol and drug abuse, and introduce potentially significant prenatal characteristics such as maternal weight loss and early gestational vaginal bleeding as aetiological correlates.

Collapse

Key Words

• aetiology
• de morsier syndrome
• optic nerve hypoplasia
• perinatal
• prenatal
• septo-optic dysplasia

Collapse

MESH Headings

• Birth Weight
• Child, Preschool
• Eye Abnormalities/epidemiology
• Female
• Gestational Age
• Humans
• Infant
• Infant, Newborn
• Infant, Premature
• Male
• Maternal Age
• North America/epidemiology
• Optic Nerve/abnormalities
• Parity
• Pregnancy
• Prospective Studies
• Registries/statistics & numerical data
• Risk Factors
• Sweden/epidemiology

Collapse

Grants

• M01 RR000043-44 NCRR NIH HHS
• UL1 RR031986 NCRR NIH HHS
• M01 RR00043 NCRR NIH HHS
• UL1 RR031986-01 NCRR NIH HHS
• M01 RR000043 NCRR NIH HHS

Collapse

Affiliation(s)

Pamela Garcia-Filion The Vision Center at Childrens Hospital Los Angeles, and Department of Ophthalmology, Keck School of Medicine, University of Southern California, Los Angeles, California 90027, USA.
Cassandra Fink
Mitchell E Geffner
Mark Borchert

Collapse

Clinical distinction between nasal optic disc hypoplasia (NOH) and glaucoma with NOH-like temporal visual field defects

Purpose:

To report on the clinically important differences between nasal optic hypoplasia (NOH) and glaucoma with NOH-like temporal visual field defect (VFD).

Method:

Five NOH (four bilateral and one unilateral) patients, three unilateral NOH patients with glaucoma, and two glaucoma patients with NOH-like temporal VFD were clinically characterized. Superior segmental optic nerve hypoplasia was also associated with glaucoma in one eye of a bilateral NOH case and the NOH eye of a unilateral NOH patient. Ocular manifestations including refractive errors, size, and appearances of the optic discs, retinal nerve fiber thickness (NFLT) ascertained by optical coherence tomography (OCT), and VFD were examined.

Results:

Ophthalmic examinations revealing NOH showed high myopia at more than −5.0D, a small disc with nasal double-ring appearance, significantly decreased NFLT by OCT, and retinal nerve fiber layer defect in the corresponding nasal sector. Stationary temporal VFD varied from a slight depression of the peripheral isopters to wide sector defects. In contrast, two glaucoma patients with NOH-like temporal VFD showed several different clinical features, including mild myopia less than −5D, a normal size with glaucomatous disc cupping; a slight decrease in nasal NFLT and progression of temporal and other glaucomatous VFD.

Conclusion:

Careful evaluation of optic disc appearance and measurement of NFLT using OCT may help to distinguish between NOH and glaucoma with NOH-like temporal VFD.

Conformal geometry of the retinal nerve fiber layer

The nerve fiber layer of the human retina is made up of the retinal segments of ganglion cell axons. Its geometry can be described mathematically as a fibration of a 2D domain: a partition of a certain region into smooth curves. Here, we present a simple family of curves that closely models the observed geometry of the nerve fiber layer. For each retina, the pattern depends on 2 parameters, A and B: A computer program determines A and B for a given retina and the theory matches the retina with a standard deviation of approximately 6-8 degrees . These particular curves turn out to be the curves that would be generated if the growing ganglion cell axon tip moved down a gradient toward a source of diffusible neuroattractant at the disk and away from a weaker macular diffusible repellant. Thus, this model provides morphological evidence that diffusible substances provide positional information to the embryonic ganglion cell axons in finding their way to the optic nerve head.

Superior segmental optic nerve hypoplasia: The topless disc syndrome

BACKGROUND

Optic 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 REPORT

A 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.

CONCLUSIONS

It 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.

Developmental abnormalities of the optic nerve and chiasm

Developmental anomalies of the optic nerve are an important and growing cause of lifelong visual handicap and they are often associated with systemic abnormalities. This review focuses on the ocular and systemic aspects of developmental anomalies arising from defects of fetal fissure closure and retinal ganglion cell development, and covers some other optic-disc anomalies that have systemic significance.

Geographical distribution of optic nerve hypoplasia and septo-optic dysplasia in Northwest England

OBJECTIVE

To study the distribution of septo-optic dysplasia (SOD) and optic nerve hypoplasia (ONH) in the Greater Manchester and Lancashire (GM&L) region of Northwest England, and to analyze occurrence by location and over time.

STUDY DESIGN

A population-based incidence study was undertaken for cases of SOD/ONH from GM&L. Standardized incidence ratio (SIR) for each district, relationships between SIRs and possible geographically varying risk factors, and spatial and space-time clustering were analyzed.

RESULTS

Eighty-seven cases had a confirmed diagnosis of ONH/SOD giving an incidence of 10.9/100,000 per year in GM&L. SIRs ranged widely but were significantly elevated (lower confidence limit >100) in three districts: 167%, 192%, and 198%, respectively. All three were high population density, inner-city locations. SIRs were significantly correlated with higher rates of unemployment (r = 0.49, P = .01), dependent children in non-earning households (r = 0.47, P = .02), underage conceptions (r = 0.46, P = .02), and underage pregnancies (r = 0.44, P = .03). There was no evidence of spatial or space-time clustering.

CONCLUSIONS

The incidence of ONH/SOD in GM&L was higher than that reported elsewhere. Cases were more common in areas that had higher unemployment and teenage pregnancy rates.

Superior segmental optic nerve hypoplasia and diabetes mellitus

PURPOSE

The aim of this study was to describe the ocular findings of an 8-year-old girl with bilateral superior segmental optic nerve hypoplasia (SSONH) whose mother had a history of Type 1 diabetes mellitus and to review the prior literature concerning this association.

METHODS

Neuroophthalmic examination, including funduscopy, visual fields, optical coherence tomography, and magnetic resonance imaging (MRI) of the brain and orbits, were used.

RESULTS

Bilateral inferior visual field defects prompted initial neuroophthalmic evaluation. Funduscopy revealed bilateral SSONH, worse on the right. MRI of the brain and orbits revealed hypoplastic optic nerves and a small optic chiasm.

CONCLUSIONS

Although the association between SSONH and maternal diabetes mellitus is a well-documented entity, prior reports have been solely in the neuroophthalmic literature. The optic discs in patients with SSONH have a characteristic appearance, which may obviate the need for additional evaluation of the visual field defects. The MRI findings of hypoplastic optic nerves and a small optic chiasm have previously not been reported. This patient underscores the importance of recognizing the association between SSONH and maternal diabetes mellitus.

Optic nerve axons: life and death before birth

In the 2004 Bowman Lecture, I give a panegyric for Sir William Bowman, an estimate of the importance and the epidemiology of anterior visual pathway developmental disorders, followed by a history of the anterior visual system. I review the normal development of the optic nerve and chiasm and the main developmental disorders: Optic Nerve Aplasia, Optic Nerve Hypoplasia and Achiasmia.

Ganglion cell axon pathfinding in the retina and optic nerve

The eye is a highly specialized structure that gathers and converts light information into neuronal signals. These signals are relayed along axons of retinal ganglion cells (RGCs) to visual centers in the brain for processing. In this review, we discuss the pathfinding tasks RGC axons face during development and the molecular mechanisms known to be involved. The data at hand support the presence of multiple axon guidance mechanisms concentrically organized around the optic nerve head, each of which appears to involve both growth-promoting and growth-inhibitory guidance molecules. Together, these strategies ensure proper optic nerve formation and establish the anatomical pathway for faithful transmission of information between the retina and the brain.

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.

Optic nerve hypoplasia: Risk factors and epidemiology

OBJECTIVES

To study the epidemiology of optic nerve hypoplasia.

DESIGN AND METHODS

Children with optic nerve hypoplasia and visual impairment were identified through the Swedish Register of Visually Impaired Children. Pre- and perinatal characteristics were obtained from the Medical Birth Registry and by scrutinizing pregnancy and delivery records. Clinical characteristics of children with optic nerve hypoplasia are described. The following risk factors were studied: maternal age, parity, maternal smoking, gestational duration, birth weight, delivery method, Apgar score, maternal disease during pregnancy, drugs used in early pregnancy.

RESULTS

Young maternal age, first parity, maternal smoking, preterm birth and factors associated with preterm birth were risk factors for optic nerve hypoplasia. There was an indicated association with the use of fertility drugs and antidepressant drugs.

CONCLUSIONS

Optic nerve hypoplasia is apparently associated not only with other anomolies, notably of the central nervous system, but also with signs of general disturbance in fetal development.