Type 1 (Classic) Granular Dystrophy
Bilateral, symmetrical, anterior stromal dystrophy
Autosomal dominant, TGFBeta1, 5q31
Type 2 is Avellino/ Combined granular-lattice dystrophy
Symptoms:
· Onset 1st decade
· Glare, photophobia
· Visual acuity is not affected in early stages
· Pain due to recurrent corneal erosions
Signs:
· Discrete white central anterior stromal opacities resembling bread crumbs/sugar granules/glass splinters in a radial/disc shaped/ Christmas tree pattern
· Stroma between opacities is clear
· Gradual increase in number and size of deposits with deeper and outward spread
· Opacities do not extend to the limbus
· Corneal sensation impaired
· Recurrent corneal erosions
Histology:
Amorphous hyaline deposits stain bright red with Masson Trichome
Treatment:
Excimer Laser Keratectomy
PK/DALK
Mnemonic for main corneal dystrophies abnormal deposits and staining
"Marylin Monroe Always Gets Her Men in L. A. County"
Macular dystrophy - Mucopolysaccharide - Alcian blue
Granular dystrophy - Hyaline materials - Masson trichrome
Lattice dystrophy - Amyloid - Congo red
Image from Rajan Eye Care Hospital