Optochiasmal avulsion secondary to minor occipital trauma.

BACKGROUND: Optic nerve avulsion is an extremely rare occurrence and usually arises in the setting of severe fronto-orbital fractures or penetrating orbital injuries. However, a few cases have been associated with minor injury. OBJECTIVE: To overview the pathophysiology of delayed optochiasmal avulsion following minor ocipital trauma and discuss management options. METHODS: Report of a unique case of a 79-year-old woman who presented with delayed partial expulsion of the right globe and complete optic nerve avulsion following closed head injury to the occiput. CONCLUSION: Antero-posterior distortion of the skull following such a deceleration injury can cause laceration and thrombosis of the pre-chiasmal and pial arteries supplying the optic chiasm. The ensuing ischaemic changes subsequently caused delayed softening of the chiasm and its avulsion. The concomitant retrobulbar haemorrhage and mass effect within the orbit consequently led to the partial expulsion of the globe.

Visual function and quality of life following vitrectomy and epiretinal membrane peel surgery.

AIM: To investigate the effect of epiretinal membrane (ERM) peel on patients' health related quality of life (HR-QOL) and to explore the association between self reported HR-QOL and conventional measures of visual function. METHODS: The National Eye Institute 25 Item Visual Function Questionnaire (VFQ-25) and the 36 Item Short-Form Health Survey (SF-36) were self administered by 20 patients before and 4 months following surgery. Preoperative and postoperative data collected included logMAR near and distant visual acuity (VA), contrast sensitivity, and metamorphopsia. Questionnaire scores were compared preoperatively and postoperatively and their correlation with traditional methods of visual function evaluation analysed. RESULTS: Postoperatively there was no significant improvement in mean logMAR VA. However, eight (40%) subjects improved by two or more ETDRS lines and nine eyes (45%) reached a final VA of 6/18 or better. Metamorphopsia decreased significantly (p = 0.019) and there was significant improvement in VFQ-25 mean scores for the general vision (p = 0.03), distance activities (p = 0.05), and composite score (p = 0.03). Baseline binocular VA was significantly correlated with baseline VFQ-25 composite score (r = 0.631, p = 0.004). CONCLUSIONS: ERM surgery appears to improve patients' subjective perception of visual function as indicated by higher composite scores in VFQ-25 and improved metamorphopsia in the absence of significant improvement in mean logMAR VA.

Long-term results of the management of silicone oil-induced raised intraocular pressure by diode laser cycloablation.

AIMS/BACKGROUND: To analyse the effectiveness and safety of cyclodiode treatment in eyes with silicone oil-related raised intraocular pressure (IOP) and to correlate the results with clinical features of treated eyes. METHODS: Retrospective review of case notes of all eyes that underwent cyclodiode treatment following injection of silicone oil at Moorfields Eye Hospital between April 1993 and January 2003 and were followed up for at least 1 year. RESULTS: In all, 38 patients were followed up for between 13 and 113 months. Totally, 17 had silicone oil in situ at the time of first treatment. The mean pretreatment IOP was 31.4 mmHg (SD 10.9), reducing to 18.6 mmHg (SD 8.6) at 1 year and to 13.9 mmHg (SD 8.4) at the final follow-up visit (P<0.001). Before treatment, 28 (73.7%) patients were on two or more topical medications. This was reduced to 18 (47.4%) patients (P=0.013) at 1 year and 13 (34.2%) patients (P=0.0007) at final follow-up. Use of oral acetazolamide for glaucoma was reduced from 16 (42.1%) patients precyclodiode to five (13.2%) patients at 1 year (P=0.0034) and three (7.9%) patients at the final visit (P=0.001). Four patients (10.5%) at 1 year and five patients (13.2%) at the final visit had hypotony (defined as IOP of less than 5 mmHg). One patient had enucleation 75 months following first cyclodiode treatment. CONCLUSION: Diode laser photocoagulation can successfully control silicone oil-induced raised intraocular pressure where medical treatment fails. Reduction of IOP appears to be maintained long term.

Laser photocoagulation alters the pattern of staining for neurotrophin-4, GFAP, and CD68 in human retina.

AIMS: To investigate the staining pattern of neurotrophin-3 (NT3), neurotrophin-4 (NT4), and brain derived neurotrophic factor (BDNF) as well as glial fibrillary acid protein (GFAP) and CD68 in lasered human retina. METHODS: Retinal laser photocoagulation was performed on four patients (two males, two females) with choroidal malignant melanoma 1-6 days before enucleation. Three other enucleated eyes with malignant melanoma and three normal cadaveric donor eyes were used as controls. Immunohistochemistry was performed to investigate the pattern of staining of NT3, NT4, BDNF, GFAP, and CD68 in 7 mm sections of fixed specimens. RESULTS: Expression of NT4 was detected in the inner and outer nuclear layers of all the retinal sections examined but no NT3 and BDNF staining was seen. NT4 staining was found to be less intense in lasered and melanoma controls compared to normal cadaveric donor retinas. There was an upregulation of GFAP expression in both lasered and control eyes with melanoma in comparison with normal controls. CD68 staining was only observed in retinal pigment epithelium and choroid of lasered eyes. CONCLUSION: NT4 is expressed in inner and outer nuclear layers of normal human retina and its expression is downregulated following laser photocoagulation. This occurs in parallel with an increased expression of GFAP suggesting that reactive changes in Muller cells may be responsible for reduced NT4 staining. Expression of CD68 at the site of laser injury is consistent with a wound healing process as a response to local damage.