====== Megalopapilla ======

  * aka Megalodisc
  * Congenital anomalous enlarged optic disc area > 2.5 mm²
  * Not associated with other morphologic anormalities
  * High prevalence in natives of Marshall Islands
  * May be unilateral or bilateral
  * Large optic cup with central pallor given the axons more thinly spread over the disc surface
  * No treatment needed 

===== Heidelberg OCT measurements =====
  * see reference 1 below
==== Nerve Areas ==== 
^ Parameter            ^ Mean  ^ SD    ^ Range      ^
| Disc area (mm²)      | 3.28  | 0.53  | 2.50-5.03  |
| Cup area (mm²)       | 1.65  | 0.5   | 0.38-2.85  |
| Rim area (mm²)       | 1.63  | 0.37  | 0.84-2.73  |
| Cup/disc ratio area  | 0.70  | 0.86  | 0.35-0.85  |


==== Nerve fiber layer thickness ====
^ OCT measure              ^ Mean    ^ SD     ^ Range         ^
| Average thickness (μm)   | 102.51  | 12.68  | 58.41-120.25  |
| Superior thickness (μm)  | 130.84  | 20.18  | 57.00-169.00  |
| Nasal thickness (μm)     | 79.67   | 15.80  | 49.00-117.00  |
| Inferior thickness (μm)  | 128.27  | 18.89  | 65.00-157.00  |
| Temporal thickness (μm)  | 70.79   | 8.46   | 55.00-92.00   |


====== References ======
  - {{::optic_disc_and_retinal_nerve_fiber_layer_thickness_descriptive_analysis_in_megalopapilla.pdf |Costa AMC et al. Optic Disc and Retinal Nerve Fiber Layer Thickness Descriptive Analysis in Megalopapilla. J Glaucoma 2014;26(6):368-371}}
  - Brodsky CM. Congenital optic disk anomalies. Surv Ophthalmol 1994;39:89-112