nanophthalmos

Poor vision is present beginning in childhood and may progress to hand motion or even loss of light perception when retinal detachments occur.  Nystagmus has been seen in one patient.  Corneal diameters were 11 mm, the angles were open, and axial lengths were shortened to about 17 mm.  Alternating areas of hypo- and hyperfluorescence are seen with fluorescein angiography corresponding to areas with pigment clumping seen throughout the fundi.  The fundus pigmentation is atypical for retinitis pigmentosa, however, in spite of the title given by the authors.  No scotopic or photopic responses are seen on the ERG.  Drusen were present in the optic nerves. 

This is a recently described type of nanophthalmos with characteristic clinical features plus retinal degeneration and optic disc drusen.  Hyperopia is common and, like another recessive form of nanophthalmos (267760), patients have a progressive retinal dystrophy beginning with granular and mottled RPE changes and progressing to a bone spicule pattern resembling retinitis pigmentosa.  No synechiae have been reported in this syndrome however.  Macular retinoschisis and cystic changes with reduced foveal reflexes are commonly present.  The anterior chamber and angles are narrow but no reported cases have had angle closure glaucoma such as frequently occurs in other forms of nanophthalmos (267760, 609549, 600165, 611897).  Drusen of the optic nerve head can be demonstrated by ultrasound.  Scleral and choroidal thickening are usually present.  There is progressive deterioration of photoreceptors beginning with rod dysfunction and eventually involving cones as documented on ERG recordings.  Nyctalopia and visual difficulties begin in childhood and the visual field is concentrically constricted.  Visual acuity is in the range of 20/100 to 20/200.

This is a rare syndrome consisting of a pigmentary degeneration of the retina in association with nanophthalmos.  The globe is small with a thickened choroid and sclera and the macula becomes atrophic later in life. Some patients have cystic macular changes early without fluorescein leakage.  The anterior chamber is shallow, the angle is narrow, and the cornea may be small leading to angle closure glaucoma in most patients.  Extensive anterior and posterior synechiae can be seen.  The retina has a postequatorial bone spicule pattern of pigmentation with narrowing of arterial vessels.  Hyperopia is usually present and nightblindness may be noted in the first decade of life.  The ERG early shows loss of rod function and progression of the retinal disease subsequently leads to extinction of all rod and cone responses by midlife.  The EOG may be subnormal and visual fields are severely constricted.  Pallor and crowding of the optic nerve are common.  The vitreous may contain prominent fibrils and fine white granules.  Visual acuity is often 20/200 or worse.