Optic disc drusen in children

The prevalance of congenital optic disc anomalies in Turkey: a hospital-based study

PURPOSE

The aim of this study was to investigate the prevalence of congenital optic disc anomalies in Turkey.

METHODS

The 11,123 eyes of 5570 patients were screened for optic disc anomalies. All patients were underwent a complete ophthalmic examination including best corrected visual acuity, refraction, spherical equivalent, slit lamp biomicroscopy, intraocular pressure measurements, dilated stereoscopic fundus examination. Data analyses were performed by using SPSS for Windows, version 22.0 (SPSS Inc., Chicago, IL, United States).

RESULTS

11,123 eyes of 5570 participants were screened. Of the 5570 participants who underwent optic disc examination, 246 eyes of 174 patients (3.12%, 95% CIs 2.66-3.58%) had optic disc anormalies. 92 (52.9%) were female, 82 (47.1%) were male and the mean of age was 44.25 ± 15.67 years. 72 (41.4%) patients were bilateral, 102 (58.6%) patients were unilateral involvement. The tilted disc was the most common anomaly and was found at least one eye in 46 patients (75 eyes) and 0.83% of all screened patients. Peripapillary myelinated nerve fibers was the second common anomaly and was found at least one eye in 31 subjects (35 eyes) and 0.56% of all screened subjects. Peripapillary atrophy was the third common anomaly, and was found in at least one eye in 24 patients (37 eyes) and 0.43% of all screened subjects.

CONCLUSION

To our knowledge, this is the first study that the prevalences of all congenital optic disc anomalies from Turkey. The prevalence of congenital optic disc anomalies is higher than in other countries.

Optic disc drusen: a systematic review : Up-to-date and future perspective

BACKGROUND

Optic disc drusen (ODD) are acellular deposits in the prelaminar optic nerve head. The most accredited theory is that they are secondary to abnormalities in axonal metabolism and degeneration, but the pathogenesis is not clear to date.

CLINICAL MANIFESTATION

Although ODD are often considered a benign condition, the great majority of patients with ODD show visual field defects and are at higher risk for developing anterior ischemic optic neuropathy. ODD are classified as superficial or buried, with the latter being often misdiagnosed as papilledema with optic nerve head swelling, leading to an unnecessary investigation for causes of increased intracranial pressure.

AIM

The recent technological improvements in OCT imaging which allowed an earlier and more certain diagnosis even of the smallest ODD, renovated the interest around this pathology. However, an updated systematic review is still missing. Therefore, the aim of this work is to provide a concise yet comprehensive overview of the current state of art, focusing on pathophysiology, clinical presentation, diagnostic methods, treatment modalities and potential future perspectives of this condition.

Optic Nerve Head Drusen: An Update

Optic nerve head drusen are benign acellular calcium concretions that usually form early in life, just anterior to the lamina cribrosa. Improving imaging using optical coherence tomography suggests they are common and may be present in many clinically normal discs. These drusen may change in appearance in early life, but are generally stable in adulthood, and may be associated with visual field defects, anterior ischaemic optic neuropathy, or rarer complications. Based on long-term clinical data and optical coherence tomography, we propose a refined hypothesis as to the cause of optic disc drusen. Here we summarise recent findings and suggest future studies to better understand the forces involved.

Acquired myelinated nerve fibers in association with optic disk drusen

Myelinated retinal nerve fibers are a well-recognized anomaly of the ocular fundus associated with many ocular and systemic conditions. Myelination is almost always congenital and stable, but progression has been documented in rare cases. Optic disk drusen are the result of a degenerative process at the optic nerve head and are often found incidentally on ophthalmologic examination. To our knowledge, optic disk drusen have only been reported once in association with acquired and progressive myelinated retinal nerve fibers. We present 2 such cases and consider the implications for the pathogenesis of myelinated nerve fibers.

The rate of visual field loss in optic nerve head drusen

PURPOSE

To define the rate of visual field loss in patients with optic nerve head drusen (ONHD).

DESIGN

Retrospective chart review.

METHODS

Goldmann visual field (GVF) testing from initial visit and last follow-up examination were quantified using the modified Esterman grid technique. The rate of visual field loss was calculated by comparing the initial GVF to the last follow-up GVF. A comparative analysis of GVF and age at initial evaluation was performed on all patients with an initial GVF only.

SETTING

Tertiary academic care center.

PARTICIPANTS

Inclusion criteria for the rate analysis: (1) diagnosis of ONHD and (2) at least 36 months of follow-up with serial GVF testing.

EXCLUSION CRITERIA

(1) patients with glaucoma or glaucoma-suspect; (2) history or examination evidence for other ocular disease; and (3) drusen-related macular causes of visual loss.

RESULTS

Thirty-two of 292 charts were included in the rate analysis. The rate of visual field loss was 1.58%. There was no statistically significant difference between men and women (P = .74). One hundred eighty patients were included in the initial visual field analysis. There was a significant negative correlation between age and GVF, with older patients having lower GVF scores with a Spearman correlation of -0.42 (P < 0.0001); 73% of these 180 patients had mild, minimal, or no visual field loss.

CONCLUSIONS

The rate of visual field loss for ONHD over a 36-month interval of time was 1.6% per year. Patients with minimal or no visual field loss were younger, and patients with moderate or severe visual loss were older.

Optic disk drusen

Optic disk drusen occur in 3.4 to 24 per 1,000 population and are bilateral in approximately 75%. Disturbance in the axonal metabolism in the presence of a small scleral canal--regardless of eyelength--is considered responsible for the development. The drusen increase in size, becoming more visible with age due to continuing calcium apposition, and they are associated with visual field defects in a considerable number of patients. Patients do not usually notice these defects, despite their progressive nature over the years, and this indicates an insidious course. A correct diagnosis of optic disk drusen is mandatory, although effective treatment is not yet available. It is most important to differentiate optic disk drusen from papilledema in order to avoid unnecessary neurological examinations, but also to avoid overlooking genuine neurologic disorders. Because optic disk drusen can cause severe visual field defects, patients require individual consultation regarding work issues and whether or not to drive. Optic disk drusen can be accompanied by vascular complications as well. In some cases these vascular changes--for example, choroidal neovascularization--are treatable. Patients with optic disk drusen should undergo regular visual field, IOP, and nerve fiber layer examinations. In patients with deteriorating visual field and borderline IOP, we recommend antiglaucomatous therapy.

Optic disc drusen and primary megalencephaly in children

Three patients with primary megalencephaly were identified among 40 children seen in our clinic with pseudopapilledema due to optic disc drusen. These patients were genetically unrelated and did not have cutaneous hemangiomas, distinguishing their condition from the Riley-Smith syndrome. Although the nature of the relationship between optic disc drusen and primary megalencephaly is not clear, we feel that the two conditions have more than a chance association. A clinically important consideration is that the concomitant occurrence of pseudopapilledema due to optic disc drusen and a large head due to primary megalencephaly may lead to an erroneous diagnosis of increased intracranial pressure in children.