Neglected Congenital Glaucoma With Lens Coloboma.

PURPOSE: To report a case of lens coloboma in a case of neglected primary congenital glaucoma. MATERIALS AND METHODS: A 5-year-old boy was brought by the parents with complaints of diminution of vision in both eyes noticed for 8 months. There was a history of enlargement of eyes since 1 year of age. RESULTS: Clinical examination revealed bilateral large eyes with limbal stretching and Haab striae and lens coloboma in the right eye. Dilated examination revealed scalloped border of the crystalline lens superotemporally with broken zonules and lens coloboma in inferotemporal quadrant with absent zonules. There was advanced optic nerve head cupping in both eyes. This lens coloboma is likely an acquired condition due to extensive stretching of the lens and zonules secondary to globe enlargement in neglected buphthalmos. CONCLUSION: A neglected case of congenital glaucoma can lead to lens subluxation along with lens coloboma.

Treatment of recurrent retinal detachment secondary to optic nerve coloboma with injection of autologous platelet concentrate.

A 14-year-old girl presented with a recurrent retinal detachment secondary to optic nerve coloboma in her left eye with a small retinal hole in the bed of the coloboma, confirmed by optical coherence tomography. The patient was treated by injection of 0.05 mL of autologous platelet concentrate into the coloboma along with vitrectomy and gas exchange. After 8 months, the retina was attached and optical coherence tomography revealed closure of the retinal hole. Considering our experience, autologous platelet injection may be considered a treatment option for recurrent retinal detachment secondary to optic nerve coloboma.

The temporal requirement for vitamin A in the developing eye: mechanism of action in optic fissure closure and new roles for the vitamin in regulating cell proliferation and adhesion in the embryonic retina.

Mammalian eye development requires vitamin A (retinol, ROL). The role of vitamin A at specific times during eye development was studied in rat fetuses made vitamin A deficient (VAD) after embryonic day (E) 10.5 (late VAD). The optic fissure does not close in late VAD embryos, and severe folding and collapse of the retina is observed at E18.5. Pitx2, a gene required for normal optic fissure closure, is dramatically downregulated in the periocular mesenchyme in late VAD embryos, and dissolution of the basal lamina does not occur at the optic fissure margin. The addition of ROL to late VAD embryos by E12.5 restores Pitx2 expression, supports dissolution of the basal lamina, and prevents coloboma, whereas supplementation at E13.5 does not. Surprisingly, ROL given as late as E13.5 completely prevents folding of the retina despite the presence of an open fetal fissure, showing that coloboma and retinal folding represent distinct VAD-dependent defects. Retinal folding due to VAD is preceded by an overall reduction in the percentage of cyclin D1 positive cells in the developing retina, (initially resulting in retinal thinning), as well as a dramatic reduction in the cell adhesion-related molecules, N-cadherin and beta-catenin. Reduction of retinal cell number combined with a loss of the normal cell-cell adhesion proteins may contribute to the collapse and folding of the retina that occurs in late VAD fetuses.

Magnesium deficiency as a cause of hypocalcemia in the CHARGE association.

OBJECTIVE: To discover the mechanism of hypocalcemia in a patient with the CHARGE (coloboma, heart disease, atresia choanae, retarded growth and development, genital hypoplasia, and ear anomalies) association. RESEARCH DESIGN: Chemical and metabolic studies of serum, urine, stool, and muscle specimens. SETTING: A university hospital affiliated with a municipal hospital. PARTICIPANT: One patient with the CHARGE association and refractory hypocalcemia. MEASUREMENTS AND RESULTS: Serum calcium level was 0.91 mmol/L (reference range, 2.20 to 2.58 mmol/L) and serum magnesium level was 0.34 mmol/L (reference range, 0.80 to 1.20 mmol/L) prior to any therapy. After parenteral calcium and magnesium therapy, hypocalcemia persisted (1.46 mmol/L), while the serum magnesium level was 0.84 mmol/L. A needle biopsy of skeletal muscle tissue for the magnesium content confirmed a total magnesium deficiency despite normomagnesemia (muscle magnesium content, 517 micrograms/g [reference range, 800 to 1100 micrograms/g]). Magnesium deficiency was secondary to secretion of magnesium into the gastrointestinal tract (with a daily magnesium intake of 190 mg, a 24-hour nondiarrheal fecal excretion of magnesium was 2019 mg/kg [reference range, < 1000 mg/kg of stool weight]). INTERVENTIONS: Hypocalcemia was corrected only after 7 weeks of continual parenteral magnesium supplements to replenish the tissue magnesium deficiency. CONCLUSIONS: Patients with the CHARGE association often have hypocalcemia. Magnesium deficiency (with or without hypomagnesemia) is a cause of the hypocalcemia in at least one patient and may prove of significance in others.

Evidence for a hypothalamic defect in septo-optic dysplasia.

A 21-year-old man demonstrated septo-optic dysplasia. Optic and retinal colobomas were present and panhypopituitarism was documented. Releasing hormone studies showed partial luteinizing hormone (LH) response and no follicle-stimulating hormone response to administration of gonadorelin (LH-releasing hormone); thyroid-stimulating hormone (TSH) and prolactin levels were increased normally after administration of protirelin (thyrotropin-releasing hormone). The LH, TSH, and prolactin responses are believed to be evidence of intact pituitary function and suggest that a hypothalamic defect accounts for the hypopituitarism.