Analysis of orbital malignancies presenting in a tertiary care hospital in Pakistan.

OBJECTIVE: To determine the frequencies of various orbital malignancies amongst orbital lesions in patients presenting in a tertiary care hospital in Pakistan. METHODS: A retrospective analysis of 666 orbital cases with an established histopathological diagnosis of malignant tumors treated in Mayo Hospital Lahore from 1996 to 2015 (20 years). RESULTS: About 66% of the malignant tumors were primary, 25% secondary, 8% haematopoietic and 1% metastatic. Almost 50% of the cases were children. Retinoblastoma is the commonest tumor (43% overall and 87% among children). Squamous cell carcinoma is the second commonest (15.6% overall and 31% among adults). These are then followed by Adenoid cystic carcinoma of Lacrimal Gland (9%), Lymphoma/Leukaemia (8%) and Rhabdomyosarcoma (6.3%). CONCLUSION: Frequencies of various orbital malignancies show geographical variation in both paediatric and adult population.

Screw implantation in the globe: the risk of delayed hardware migration from craniofacial repair.

Plating system modification has enabled the use of rigid fixation in younger patients having maxillofacial surgery. One of the common reported complications of the use of plates and screws in children is screw migration due to skeletal maturation. Ophthalmic complications due to maxillofacial surgery reported to date include oculomotor and abducens palsies, lacrimal damage and vision loss due to infection, retrobulbar hemorrhage, and compartment syndrome. We describe a complication unique to screw migration resulting in orbital fixation and near-globe rupture in a patient with Treacher Collins syndrome. We hope to alert our colleagues to the potential risk of screw and hardware migration and breakage, particularly in the setting of craniofacial surgery performed on a child before maturation of craniofacial osseous structures.

Retinopathy of prematurity in Pakistan.

Screening guidelines for retinopathy of prematurity recommended by the American Academy of Pediatrics and the American Association for Pediatric Ophthalmology and Strabismus suggest screening infants of birth weight of ≤1500 g and/or 32 weeks' gestational age or less. In developing and middle-income countries, ROP has been reported in older and/or heavier infants. We prospectively studied 172 infants of gestational age 36 weeks and younger and/or birth weight of ≤3000 g over a period of 16 months. ROP was identified in 4 infants >32 weeks of age, 1 infant having a birth weight of 2000 g. ROP was diagnosed in premature babies heavier than those seen internationally.

Eyelid Lacerations Due to Dog Bite in Children.

PURPOSE: To evaluate the nature and extent of lacrimal apparatus injury in children after eyelid laceration from a dog bite. METHODS: A retrospective chart review of all eyelid lacerations treated between 1990 and 2012 at Boston Children's Hospital, Boston, Massachusetts, was conducted. Seventy-three patients who sustained an eyelid laceration due to dog bite were identified and were matched 5:1 with a randomly selected cohort of 365 patients from the group of 1,177 patients who had sustained eyelid lacerations from other causes during the same time period. RESULTS: Of the 73 patients who sustained an eyelid laceration due to a dog bite, 26 (35.62%) had damage to the lacrimal apparatus. This was statistically significant when compared to patients who sustained eyelid lacerations from other causes, in which 13 (3.56%) patients had damage to the lacrimal apparatus (P < .000001). The inferior canaliculus was the most commonly involved site of lacrimal apparatus trauma as a result of a dog bite. Success was defined as lack of epiphora at the time of the last follow-up. Early surgical management of eyelid lacerations with lacrimal apparatus involvement had a success rate of 82%. CONCLUSIONS: Eyelid lacerations due to dog bites have a greater prevalence of involvement of the lacrimal apparatus and especially the inferior canaliculus than lacerations due to other causes in children. Clinicians should have a high index of suspicion for lacrimal apparatus involvement and be prepared for surgical repair, if indicated.

Genetics of strabismus and lid diseases.

The prevalence of congenital ocular malformations has been described to vary from 0.04 to 6.8 per 10,000 live births. The nuclear mutations identified in chronic progressive external ophthalmoplegia harbor multiple mtDNA deletions that include POLG mutations, PEO1 mutations, OPA1 mutations and RRM2B mutations. In Kearns-Sayre syndrome, the spontaneous mitochondrial deletions vary from 1.3 to 8.0 kb subunits of the oxidative phosphorylation enzymes and several t-RNA genes are affected. Oculopharyngeal muscle dystrophy is both autosomal dominant and recessive form. Congenital fibrosis of extraocular muscles (CFEOM) 1 has mutations in KIF21A on chromosome 12 with TUBB3 mutation also being seen. CFEOM 2 is an autosomal recessive, genetically distinct entity with homozygous mutations in PHOX2A. CFEOM 3 is autosomal dominant heterozygous missense mutations in TUBB3. Most cases of Mobius syndrome are sporadic with familial cases being autosomal dominant, autosomal recessive or X-linked recessive inheritance. Genetic testing has shown abnormalities involving chromosome 1 and 13. Presynaptic congenital myasthenic syndrome is caused by ChAT (choline acetyltransferase) mutation. Two loci have been found for myotonic dystrophy (DM). DM1, which is associated with trinucleotide expansion on chromosome 19q13.3 and DM2 which is associated with CCTG tetranucleotide expansion at 3q21. Blepharophimosis is caused by mutations in the FOXL2 gene 49 located at chromosome 3q23. Lymphedema-distichiasis is an autosomal dominant disorder caused by mutations in the FOXC2 gene.

Adjustable nasal transposition of split lateral rectus muscle for third nerve palsy.

IMPORTANCE: Third nerve palsy causes disfiguring, incomitant strabismus with limited options for correction. OBJECTIVE: To evaluate the oculomotor outcomes, anatomical changes, and complications associated with adjustable nasal transposition of the split lateral rectus (LR) muscle, a novel technique for managing strabismus associated with third nerve palsy. DESIGN, SETTING, AND PARTICIPANTS: Retrospective medical record review appraising outcomes of 6 consecutive patients with third nerve palsy who underwent adjustable nasal transposition of the split LR muscle between 2010 and 2012 with follow-up of 5 to 25 months at a tertiary referral center. INTERVENTION: Adjustable nasal transposition of the split LR muscle. MAIN OUTCOMES AND MEASURES: The primary outcome was postoperative horizontal and vertical alignment. Secondary outcomes were (1) appraising the utility of adjustable positioning, (2) demonstrating the resultant anatomical changes using magnetic resonance imaging, and (3) identifying associated complications. RESULTS: Four of 6 patients successfully underwent the procedure. Of these, 3 patients achieved orthotropia. Median preoperative horizontal deviation was 68 prism diopters of exotropia and median postoperative horizontal deviation was 0 prism diopters (P = .04). Two patients had preoperative vertical misalignment that resolved with surgery. All 4 patients underwent intraoperative adjustment of LR positioning. Imaging demonstrated nasal redirection of each half of the LR muscle around the posterior globe, avoiding contact with the optic nerve; the apex of the split sat posterior to the globe. One patient had transient choroidal effusion and undercorrection. Imaging revealed, in this case, the apex of the split in contact with the globe at an anterolateral location, suggesting an inadequate posterior extent of the split. In 2 patients, the surgical procedure was not completed because of an inability to nasally transpose a previously operated-on LR muscle. CONCLUSIONS AND RELEVANCE: Adjustable nasal transposition of the split LR muscle can achieve excellent oculomotor alignment in some cases of third nerve palsy. The adjustable modification allows optimization of horizontal and vertical alignment. Imaging confirms that the split LR muscle tethers the globe, rotating it toward primary position. Case selection is critical because severe LR contracture, extensive scarring from prior strabismus surgery, or inadequate splitting of the LR muscle may reduce the likelihood of success and increase the risk of sight-threatening complications. Considering this uncertainty, more experience is necessary before widespread adoption of this technique should be considered.