Clinical and morphological features of Waardenburg syndrome type II

Evaluation of 4-month-old girl who presented with congenital cataracts revealed heterochromia iridis, fundus hypopigmentation, residual white forelock and sensory neural hearing loss--findings consistent with Waardenburg syndrome type II. Bilateral peripheral iridectomies performed at lensectomy provided tissue for evaluation. Light microscopy revealed fewer melanocytes in the blue iris than in the brown. Electron microscopic examination showed a significant (p = 0.0001) reduction in melanosome size in the blue iris, and the nerve endings contained fewer vesicles. A defect in neural crest cell migration and melanin synthesis may be responsible for the heterochromia iridis seen in Waardenburg syndrome type II.

Secondary squamous cell carcinoma of the orbit

OBJECTIVE

To evaluate the origin and biological behavior of secondary orbital squamous cell (SCC) and mucoepidermoid carcinoma.

METHODS

A retrospective review of 30 consecutive patients with SCC and mucoepidermoid carcinoma of the orbit seen over a period of 8 years at a large ophthalmic hospital in Saudi Arabia.

RESULTS

A total of 51 secondary orbital tumors were seen in the 8-year period from 1983 through 1991; 30 (60%) of the 51 cases were SCC. There were 16 male and 14 female patients, with an age range of 38 to 80 years and a mean age of 65 years. In 28 (93%) of the 30 patients, the tumor originated in the conjunctiva. Orbital involvement by conjunctival SCC was the most common cause of secondary orbital tumors encountered in patients older than 19 years. Four patients had concomitant paranasal sinus involvement, 4 patients exhibited intraocular invasion, and 2 others were found to have intracranial extension of the SCC. Six (20%) of the 28 patients developed regional lymph node metastases during the course of their illness. All patients were treated by orbital exenteration, with or without radiation therapy. Seven (23%) of the 28 patients died of their disease.

CONCLUSIONS

Orbital SCC is an aggressive and life-threatening condition. Most cases result from secondary extension of conjunctival SCC, a common disease in Saudi Arabia. Several factors contribute to the aggressiveness of conjunctival SCC in this geographic location, including continual exposure to UV rays, chronic irritation, and genetic factors. Delay in presentation for treatment, inadequate initial resection of conjunctival lesions, and the aggressive mucoepidermoid carcinoma variant of SCC are also factors contributing to orbital invasion.

Ectopic (extradural) meningioma of the orbit: a report of two cases in children

Meningiomas arising from the optic nerve or secondarily invading the orbit from the intracranial cavity are uncommonly encountered in children. Ectopic (extradural) meningiomas are exceedingly rare orbital tumors that do not originate from either the optic nerve or the intracranial meninges. We evaluated and treated two boys aged 7 and 10 years with probable primary ectopic (extradural) orbital meningiomas. Both patients presented with a gradual onset of progressive, painless proptosis. In addition, computed tomographic scans demonstrated involvement of the superomedial orbit without bony erosion or hyperostosis, but with expansion of the adjacent sinus. Neither tumor demonstrated attachment to the optic nerve or intracranial extension at the time of surgery. Both patients were successfully treated with complete surgical excision. Evaluation did not reveal the presence of neurofibromatosis in either child.

Wolfring dacryops

BACKGROUND

A unique series of 13 cases of ductal cysts of the accessory lacrimal glands of Wolfring is presented. Once appreciated, they are an easily recognized clinical entity.

METHODS

The 13 cases were verified histologically as arising from ductal epithelium. Biochemical analyses for serum and cyst fluid concentrations of IgA, IgG, and IgM were performed on three of the cases. Histologic staining of the cyst wall using monoclonal antibodies to immunoglobulins was performed on one case.

FINDINGS

All patients had evidence of extensive trachomatous scarring. High levels of IgA were found in the cyst fluid, consistent with an active secretory mechanism. Monoclonal antibody staining suggested a significant role for paraductal IgA-secreting plasma cells.

CONCLUSION

The formation of a ductal cyst appears to require two successive, inter-related events. The first is an ongoing active secretory process, and the second is an occlusion of the duct. The sequential occurrence of these two events is forwarded as the explanation of dacryops formation. Excision using a conjunctival approach is recommended. A small strip of tarsal border should be removed with the cyst to prevent cyst rupture. The excretory ducts of the Wolfring glands exit through this area.

Use of the Arden grating test for screening

One hundred and forty patients were referred for a clinical evaluation of their eyes, having produced high scores on screening by the Arden grating test (AGT). In these patients 66% of the eyes were found to be normal, 31% abnormal, and 3% indeterminate on clinical examination. Suitable criteria for referral for clinical examination were determined and the recommended scores are: (a) A total AGT score of greater than or equal to 80; (b) One or more plates scoring greater than or equal to 17; (c) A difference between the two eyes of greater than or equal to 13. With these criteria at least 95% of the abnormal eyes will be detected. As a screening test the AGT is equal to the Snellen distance visual acuity test at separating the normal group from the abnormal group, and on the recommended criteria the AGT gives a better ratio of false positives to false negatives.