Case report: Unilateral optic nerve aplasia and developmental hemi-chiasmal dysplasia with VEP misrouting.

PURPOSE: To describe the trans-occipital asymmetries of pattern and flash visual evoked potentials (VEPs), in an infant with MRI findings of unilateral optic nerve aplasia and hemi-chiasm dysplasia. METHODS: A child with suspected left cystic microphthalmia, left microcornea, left unilateral optic nerve aplasia, and hemi-chiasm underwent a multi-channel VEP assessment with pattern reversal, pattern onset, and flash stimulation at the age of 16 weeks. RESULTS: There was no VEP evidence of any post-retinal visual pathway activation from left eye with optic nerve aplasia. The VEP trans-occipital distribution from the functional right eye was skewed markedly across the midline, in keeping with significant misrouting of optic nerve fibres at the chiasm. This was supported by the anatomical trajectory of the optic chiasm and tracts seen on MRI. CONCLUSION: This infant has chiasmal misrouting in association with unilateral optic nerve aplasia and unilateral microphthalmos. Chiasmal misrouting has not been found in patients with microphthalmos or anophthalmos, but has been reported after early eye loss in animal models. Our findings contribute to our understanding of the discrepancy between the visual pathway physiology of human unilateral microphthalmia and animal models.

Cranio-orbital Resection Does Not Appear to Improve Survival of Patients With Lacrimal Gland Carcinoma.

PURPOSE: To ascertain long-term outcome of treatment for primary epithelial malignancies of the lacrimal gland and compare outcomes after cranio-orbital resection or after macroscopic tumor resection with radiotherapy. METHODS: Comparative case series of 79 patients (49 male; 62%) treated for primary epithelial malignancies of the lacrimal gland at Moorfields Eye Hospital between 1972 and 2014. Patients were identified from clinical and pathological databases and, where available, the clinical, pathological, and imaging records reviewed. The primary outcome measures were overall survival after diagnosis, disease-free survival, and final visual acuity for patients having cranio-orbital resection (exenteration plus local bone removal), compared with macroscopic tumor resection plus radiotherapy. RESULTS: The mean age at presentation was 48 years (median: 50 years; range: 13-84 years), with 53 (67%) having adenoid cystic carcinoma, 15 (19%), primary adenocarcinoma, and 11 (14%) carcinoma ex-pleomorphic adenoma (malignant mixed tumor). The overall survival probability of the cohort (79 patients) was 0.59 at 5 years and 0.52 at 10 years, with 36/79 (46%) patients suffering tumor-related deaths; 14 patients died from other causes, and 4 patients were lost to follow up after the minimum follow-up period. The probability of disease-free survival at 5 years for patients with adenoid cystic carcinoma, adenocarcinoma, and malignant mixed tumor was 0.52, 0.4, and 0.64, respectively, with the comparable figures at 10 years being 0.44, 0.40, and 0.64. Most importantly, the 9 patients undergoing cranio-orbital resection and the 44 having solely macroscopic tumor resection plus radiotherapy had similar overall survival (p = 0.59) and disease-free survival (p = 0.89). Subgroup analysis of the 2 treatment modalities for patients with adenoid cystic carcinoma (8 cranio-orbital resection and 32 debulking and radiotherapy) demonstrated similar results for disease-free survival (p = 0.87). Likewise, there were no significant differences between rates of recurrences between the 2 different treatments. For the 50 patients who had eye-preserving surgery and long-term visual acuity data, the final acuity was better or equal to 0.6 logMAR (6/24 Snellen) in 25 (50%). DISCUSSION: There is no difference in either survival or tumor recurrence for lacrimal gland carcinoma treated with cranio-orbital resection, or eye-preserving tumor excision and radiotherapy. The authors, therefore, continue to advocate local resection and radiotherapy for almost all patients with primary epithelial malignancies of the lacrimal gland-this treatment having lower morbidity, causing less disfigurement, and, importantly, preserving useful vision in most patients.

Corneal complications after orbital radiotherapy for primary epithelial malignancies of the lacrimal gland.

PURPOSE: To review the long-term corneal complications after high-dose external beam orbital radiotherapy given to patients for lacrimal gland carcinomas. The impact of prophylactic measures to improve long-term ocular surface health is also assessed. DESIGN: Retrospective case series. PARTICIPANTS: Patients under the care of Moorfields Eye Hospital and receiving external beam radiotherapy for primary epithelial lacrimal gland carcinoma between 1975 and 2014. METHODS: Retrospective review of ophthalmic case notes at Moorfields Eye Hospital, and oncology and general physician records. MAIN OUTCOME MEASURES: The occurrence of corneal perforation, and time to perforation. RESULTS: Sixty-seven patients were included in this study, of whom nine (13%) developed corneal perforation at a median time of 10.4 months after radiotherapy (mean 35; range 3.2 months to 14.5 years); the majority (7/9; 78%) perforated within 36 months of radiotherapy. The mean follow-up interval of the whole cohort was 8.2 years (median 4.6; range, 2 months to 30.7 years). CONCLUSIONS: Although most patients with globe-sparing treatment of lacrimal gland carcinoma did not suffer corneal perforation, they usually require long-term therapy to maintain the ocular surface. The high-dose external beam radiotherapy needed for lacrimal gland carcinoma can produce significant ocular surface morbidity, and the 13% incidence of corneal perforation was greatest in the first 3 years after irradiation.

Radiological Comparison of the Lacrimal Sac Fossa Anatomy Between Black Africans and Caucasians.

PURPOSE: To compare, in black Africans and Caucasians, the radiological anatomy of the intranasal structures and lacrimal sac fossa as relevant to dacryocystorhinostomy. METHODS: 0.75 mm section cranio-orbital computed tomography scans from 72 patients (42 black Africans and 30 Caucasian) were included in this retrospective observational case series. Only one orbit from each scan was utilized. The main outcome measures were: the thickness and proportions of the lacrimal bone and frontal process of the maxilla evaluated at 3 axial planes (upper, middle, lower) in the lacrimal sac fossa; 2 measurements of maxillary thickness were obtained at each plane-namely, the "midpoint thickness" and the "maximum thickness." The anterior extent of the nasal mucosa was also evaluated. RESULTS: The frontal process of the maxilla was thickest inferiorly (p < 0.001) and the maximum maxillary thickness was significantly thicker in black Africans as compared with Caucasians (p < 0.001) at all planes. At midfossa level, the proportion of maxillary bone forming the lacrimal fossa wall was significantly greater in black Africans (p < 0.01). In contrast, the length of nasal mucosa available for creation of an anastomosis, as estimated from the greatest mucosal height, was significantly greater in Caucasians (p < 0.01). CONCLUSIONS: Black Africans have a lacrimal sac fossa bounded by thicker maxillary bone, this bone constituting a higher proportion of the fossa wall at its midpoint, and also have significantly less nasal mucosa available for soft-tissue anastomosis during lacrimal drainage surgery. The anterior lacrimal crest, comprising the frontal process of the maxilla, was thickest at the lowest plane in both black Africans and Caucasians.