Dinesh Selva

Orbital Compartment Syndrome: The Ophthalmic Surgical Emergency

Orbital compartment syndrome is an uncommon, ophthalmic surgical emergency characterized by an acute rise in orbital pressure. When intraorbital tension rises, damage to ocular and other intraorbital structures, including irreversible blindness, may occur if not promptly treated. The diagnosis of orbital compartment syndrome is completely clinical and early recognition and emergent orbital decompression (even prior to imaging) is essential in preventing permanent vision loss. Lateral canthotomy and inferior cantholysis remain the mainstays of management. More extensive incision of the orbital septum and orbital bony decompression may be necessary in unresponsive cases. This review discusses the various etiologies and mechanisms resulting in orbital compartment syndrome, clinical features, imaging findings, treatment, and prognosis.

Mitomycin : Clinical applications in ophthalmic practice

Mitomycin (mitomycin C; MMC) is an antibiotic isolated from Streptomyces caespitosus. The drug is a bioreductive alkylating agent that undergoes metabolic reductive activation, and has various oxygen tension-dependent cytotoxic effects on cells, including the cross-linking of DNA. It is widely used systemically for the treatment of malignancies, and has gained popularity as topical adjunctive therapy in ocular and adnexal surgery over the past 2 decades. In ophthalmic medicine, it is principally used to inhibit the wound healing response and reduce scarring of surgically fashioned ostia. Hence, it has been used as adjunctive therapy in various ocular surgeries, such as glaucoma filtering surgeries, dacryocystorhinostomy, corneal refractive surgery and surgeries for ocular cicatrisation. In addition, it has been used as an adjunct in the surgical management of pterygia, ocular surface squamous neoplasia, primary acquired melanosis with atypia and conjunctival melanoma. In many of these surgeries and ophthalmic pathologies, MMC showed a significant beneficial effect.

Comparison of the ICare rebound tonometer with the Goldmann applanation tonometer by experienced and inexperienced tonometrists.

PurposeTo assess the agreement between ICare® rebound tonometer and Goldmann applanation tonometer in the hands of experienced and inexperienced tonometrists.Patients and methodsTwo tonometrists, experienced with both Goldmann applanation tonometry (GAT) and ICare® Tonometry (ICT) measured intraocular pressure (IOP), in a masked fashion, in 100 patients. In another series of 58 patients, ICT was performed by an inexperienced tonometrist and GAT by an experienced tonometrist.ResultsIn approximately 80% of patients, the difference in IOP between GAT and ICT was ⩽2 mmHg in group 1 and ⩽3 mmHg in group 2. The 95% limits of agreement were −4.0–4.4 mmHg in group 1 and −6.0–5.0 mmHg in group 2.ConclusionICT compares reasonably with GAT, in both experienced and inexperienced hands. Its ease of use, portability, and sterility make it an attractive tonometer. Its degree of accuracy in inexperienced hands would make it a useful instrument for health care workers with limited ophthalmic experience.

IgG4-related orbital disease: a meta-analysis and review

IgG4‐related orbital disease (IgG4‐ROD) is a recently described condition that may account for a significant proportion of idiopathic lymphoplasmacytic or sclerotic orbital lesions. This study is the first meta‐analysis of published cases and reveals several differences between IgG4‐related disease affecting the orbit and that affecting the pancreas. IgG4‐ROD affects a slightly younger group of patients, affects men and women approximately equally, is commonly associated with salivary gland lesions, is associated with a relatively higher serum IgG4 and may confer an increased risk of non‐Hodgkin Lymphoma. Its pathogenesis may involve an immune response to antigen exposure in the upper aerodigestive tract.

Prevalence of glaucoma in rural Myanmar : the Meiktila Eye Study

Aim: To determine the prevalence of glaucoma in the Meiktila district of central, rural Myanmar. Methods: A cross-sectional, population-based survey of inhabitants ⩾40 years of age from villages in Meiktila district, Myanmar, was performed; 2481 eligible participants were identified and 2076 participated in the study. The ophthalmic examination included Snellen visual acuity, slit-lamp examination, tonometry, gonioscopy, dilated stereoscopic fundus examination and full-threshold perimetry. Glaucoma was classified into clinical subtypes and categorised into three levels according to diagnostic evidence. Results: Glaucoma was diagnosed in 1997 (80.5%) participants. The prevalence of glaucoma of any category in at least one eye was 4.9% (95% CI 4.1 to 5.7; n = 101). The overall prevalence of primary angle-closure glaucoma (PACG) was 2.5% (95% CI 1.5 to 3.5) and of primary open-angle glaucoma (POAG) was 2.0% (95% CI 0.9 to 3.1). PACG accounted for 84% of all blindness due to glaucoma, with the majority due to acute angle-closure glaucoma (AACG). Conclusion: The prevalence of glaucoma in the population aged ⩾40 years in rural, central Myanmar was 4.9%. The ratio of PACG to POAG was approximately 1.25:1. PACG has a high visual morbidity and AACG is visually devastating in this community. Screening programmes should be directed at PACG, and further study of the underlying mechanisms of PACG is needed in this population.

Orbital Metastasis: Clinical Features, Management and Outcome

Purpose: To review the clinical features, treatment, outcome and survival of metastatic tumors of the orbit. Materials and Methods: Retrospective, non-comparative, chart review of 80 patients with orbital metastasis treated in four tertiary orbital centres in Australia. Results: The study included 80 patients of which, 44 were male with a mean age of 60 years. Orbital involvement commonly presented late in a multisystemic disease; however, the orbit was the first presentation in 15% of the cases. Diplopia (48%), pain (42%), and visual loss (30%) were the commonest symptoms at presentation; whereas proptosis (63%), strabismus (62%), and visual loss (41%) were the most frequent clinical signs. Computed tomography commonly showed a solid enhancing mass (42 cases) located within the orbital fat (43%), or enlarging an extraocular muscle (28%). Breast carcinoma (29%), melanoma (20%), and prostatic cancer (13%) were the most frequent histological types. Treatment was often multi-disciplinary and modalities included radiotherapy, chemotherapy, hormone therapy, surgery, and immunotherapy. Survival was limited to 1.5 years after diagnosis independent of the histological type, with 29% of patients alive after 17 months follow-up. Conclusions: A high index of suspicion and appropriate intervention with histological diagnosis can help in the management and quality of life in patients with metastatic orbital disease. Overall survival is limited and we encountered statistical limitations proving differences in the survival based on the sub-type of primary tumour involved. Metastatic orbital melanoma presented a higher incidence when compared with previous studies, probably due to the increase frequency of skin found in the Australian population.

American Joint Committee on Cancer Classification Predicts Outcome of Patients with Lacrimal Gland Adenoid Cystic Carcinoma

PURPOSE To investigate whether American Joint Committee on Cancer (AJCC) classification at initial diagnosis of lacrimal gland adenoid cystic carcinoma predicts outcome of treatment on local recurrence. DESIGN Retrospective chart review. PARTICIPANTS Consecutive patients with adenoid cystic carcinoma of the lacrimal gland treated at 8 institutions between January 1986 and December 2007. METHODS Clinical records, including pathology reports and imaging studies, were reviewed. MAIN OUTCOME MEASURES AJCC classification, histologic subtype, local recurrence rate, and survival. RESULTS AJCC classification at initial diagnosis was assessable for 53 patients and was as follows: T1N0M0, 7 patients; T2N0M0, 8 patients; T3aN0M0, 14 patients; T3aNxM0, 1 patient; T3aN0M1, 1 patient; T3bN0M0, 13 patients; T3bN0M1, 1 patient; T4aN0M0, 2 patients; T4bN0M0, 4 patients; T4bN0M1, 1 patient; and T4bNXM0, 1 patient. Thirty-eight (72%) of the 53 patients had >T3 tumors at presentation. Of the 38 patients with >T3 tumors, 20 were treated with orbital exenteration and postoperative adjuvant radiotherapy (RT), 6 were treated with orbital exenteration without RT, and 12 were treated with globe-preserving surgery (10 with RT and 2 without RT). Of the 15 patients with <T3 tumors, 6 were treated with globe-preserving surgery and RT, 2 were treated with globe-preserving surgery without RT, 6 were treated with orbital exenteration with bone removal and RT, and 1 was treated with orbital exenteration with bone removal without RT. Only 1 patient with a <T3 tumor, had local recurrence. Among patients with >T3 tumors, the risk of local recurrence (in the orbit or skull base) was higher in patients treated with conservative surgery as opposed to orbital exenteration and RT. Only 4 (20%) of the 20 patients treated with orbital exenteration and RT had local recurrence, compared with 3 (50%) of the 6 patients treated with orbital exenteration without RT and 8 (67%) of the 12 patients treated with globe-preserving surgery. Overall, 17 (45%) of the 38 patients with >T3 tumors and only 1 (7%) of the 15 patients with <T3 tumors died of disease during the study period. CONCLUSIONS In patients with lacrimal gland adenoid cystic carcinoma, AJCC >T3 disease at initial diagnosis correlates with worse outcomes than does AJCC <T3 disease. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Lower eyelid anatomy: an update.

Eyelid surgery necessitates a thorough knowledge of eyelid anatomy. Recent contributions to the literature have significantly advanced our understanding of eyelid anatomy. In this review, we present an update of the anatomy and the implications for upper eyelid surgery. Aspects to be covered include the levator aponeurosis, Müllers muscle, lamina propria mucosae of conjunctiva, orbital septum, myoneural junction of the levator palpebrae superioris muscle, adipose tissue, and the ligament system.

Endogenous endophthalmitis: A 13-year review at a tertiary hospital in South Australia

This retrospective report presents a series of patients with endogenous endophthalmitis treated over a 13-y period in a tertiary care centre in South Australia. 16 eyes of 13 patients (8 M, 5F) with a mean age 62 y were included. Systemic predisposing risk factors were mainly diabetes mellitus (30.7%), chronic obstructive airway disease (23.1%) and end-stage renal disease (15.4%). Isolated organisms included fungal species in 11 eyes (7 eyes with Candida albicans and 4 with Aspergillus fumigatus), Gram-positive isolates in 4 eyes, and Pseudomonas aeruginosa in 1 eye. Presenting visual acuity was 20/200 or lower in 8 patients (61.5%). Final visual improvement of more than 2 lines was noted in 5 patients, it was stable or worse in 6 patients and in 2 patients the eye was either enucleated or eviscerated. Systemic aspergillosis resulted in death of both patients. In conclusion, the clinical course and microbiological profile of pathogens in patients with endogenous endophthalmitis in our series are similar to other recent western reports. Candida species are the leading isolates, with an overall poor visual prognosis, especially in Aspergillus infections. Close monitoring of immune-compromized patients with systemic infections may enable early diagnosis and treatment and improve prognosis.

Ocular biometry and determinants of refractive error in rural Myanmar: The Meiktila Eye Study.

Objective: To describe the ocular biometry and determinants of refractive error in an adult population in Myanmar. Methods: A cross-sectional, population-based survey of the inhabitants 40 years of age and over from villages in the Meiktila District was performed; 2481 eligible participants were identified, and 2076 participated in the study. Biometric components including axial length (AL), anterior chamber depth (ACD), vitreous chamber depth (VCD), lens thickness (LT) and corneal curvature (CC) were measured. Lens opalescence was measured using the Lens Opacity Grading System III. Non-cycloplegic refraction was measured with an autorefractor. Results: Complete biometric, refractive and lenticular data were available on 1498 participants. Men had longer ALs, ACDs, VCDs and steeper CCs than women. There was an increase in LT, nuclear opalescence (NO) and myopic shift with increasing age, with no significant change in AL with age. In the 40–59 year age group, VCD was a significant predictor of refractive error, but LT (p<0.001) and NO (p<0.001) were stronger predictors. In the 60+ age group, NO (p<0.001) was also the dominant predictor of refractive error. Conclusion: This Burmese population, particularly women, has a relatively short AL and ACD. NO is the strongest predictor of refractive error across all age groups in this population.