Microphthalmia with Retinitis Pigmentosa

Clinical Characteristics
Ocular Features: 

A decrease in visual acuity with night blindness begins in the third decade of life.  The axial length is decreased resulting in high hyperopia.  There is diffuse scleral thickening, macular schisis of the outer retinal layers, and drusen may be present in the optic nerve.  The retinal pigment epithelium is abnormal with both pigment clumping and bone-spicule formation.  Areas of hypo- and hyperfluorescence are seen on fluorescein angiograms.  The cornea is normal-sized with shallow anterior chambers but narrow angles were not reported.  Intraocular pressures were normal.  On ERG recordings rod responses are missing while cone tracings are severely diminished. 

Systemic Features: 

No systemic disease is associated. 

Genetics

Based on consanguinity in the parents of the single family reported, this seems to be an autosomal recessive disorder.  Molecular studies confirm that the four affected sibs are homozygous for mutations in the MFRP gene (11q23) while the parents are both heterozygous.

Another disorder of small eyes but with classical findings of nanophthalmos and retinitis pigmentosa has also been described (267760) (nanophthalmos with retinopathy) and may be the same disorder especially since no molecular mutation has been identified.  

Treatment
Treatment Options: 

Low vision aids may be helpful, at least in early stages of the disease. 

References
Article Title: 

References

Ayala-Ramirez R, Graue-Wiechers F, Robredo V, Amato-Almanza M, Horta-Diez I, Zenteno JC. A new autosomal recessive syndrome consisting of posterior microphthalmos, retinitis pigmentosa, foveoschisis, and optic disc drusen is caused by a MFRP gene mutation. Mol Vis. 2006 Dec 4;12:1483-9.

PubMedID: 17167404