Comparison of two different optical coherence tomography angiography devices in detecting healthy versus glaucomatous eyes - an observational cross-sectional study.

BACKGROUND: To understand the differences between two different optical coherence tomography angiography (OCTA) devices in detecting glaucomatous from healthy eyes by comparing their vascular parameters, diagnostic accuracy and test-retest reliability. METHODS: A cross-sectional observational study was performed on healthy and glaucoma subjects, on whom two sets of OCTA images of optic disc and macula were acquired using both AngioVue (Optovue, USA) and Swept Source (Topcon, Japan) OCTA devices during one visit. A novel in-house software was used to calculate the vessel densities. Diagnostic accuracy of the machines in differentiating healthy versus glaucomatous eyes was determined using area under the receiver operating characteristic curve (AUROC) and test-retest repeatability of the machines was also evaluated. RESULTS: A total of 80 healthy and 38 glaucomatous eyes were evaluated. Glaucomatous eyes had reduced mean vessel density compared to healthy controls in all segmented layers of the optic disc and macula using AngioVue (p ≤ 0.001). However, glaucomatous eyes had higher mean vessel density on optic disc scans using Swept Source, with lack of statistically significant difference between healthy and glaucomatous eyes. The AUROC showed better diagnostic accuracy of AngioVue (0.761-1.000) compared to Swept Source (0.113-0.644). The test-retest reliability indices were generally better using AngioVue than Swept Source. CONCLUSIONS: AngioVue showed better diagnostic capability and test-retest reliability compared to Swept Source. Further studies need to be undertaken to evaluate if there is any significant difference between the various machines in diagnosing and monitoring glaucoma.

An unusual presentation of a giant frontal sinus mucocele manifesting with a subcutaneous forehead mass.

INTRODUCTION: To describe the unusual manifestation of a giant frontal sinus mucocele. CLINICAL PICTURE: A 33-year-old female presented with blurring of vision in the left eye, periorbital swelling and a painless forehead mass. There was proptosis, partial ptosis, and an elongated, soft, subcutaneous mass over the left side of the forehead. CT scan showed a mass arising from the frontal sinus with both intraorbital and intracranial extension. TREATMENT: Surgical excision of the mass confirmed the diagnosis of a mucocele. OUTCOME: Postoperatively, the patient was asymptomatic. CONCLUSIONS: A subcutaneous soft-tissue mass may be the presenting complaint of a frontal mucocele. Careful examination of the surrounding skin may suggest the diagnosis of sinus-related disease and thus direct appropriate investigations.

"I've got a UFO stuck in my throat!"--an interesting case of foreign body impaction in the oesophagus.

This is a case report of an elderly lady with odynophagia because she accidentally swallowed a tablet which was still wrapped in its blister pack. A discussion of foreign body ingestion, particularly in the elderly, is included. To the authors' knowledge, this is the first paper that includes a lateral cervical radiograph of an ingested blister pack.

Ocular manifestations and complications of Stevens-Johnson syndrome and toxic epidermal necrolysis: an Asian series.

BACKGROUND: To describe the acute and late ocular manifestations and complications in toxic epidermal necrosis (TEN) and Stevens-Johnson syndrome (SJS), and identify predictors for development of late complications. METHODS: Cases of TEN and SJS during a 9-year period were included. Patients with ocular involvement were reviewed for acute ocular complications. Patients with a minimum 6 months follow-up were reviewed for late complications. Records were reviewed for their demographics, etiology, and severity of ocular involvement. RESULTS: There were 117 patients with a mean age of 52.2 +/- 18.6 years. Eighty-one of these (69%) had acute ocular involvement. This was mild in 40%, moderate in 25% and severe in 4%. Adverse drug reactions were the predominant cause. Patients with thrombocytopenia had more severe acute ocular involvement. Forty-four patients had a minimum 6 months of follow-up and half developed late complications. Severe dry eyes and trichiatic lashes were the commonest late complications. Patients treated with topical antibiotic were more likely to have late complications, particularly dry eyes. There was no difference in the severity of acute eye involvement or late complications when SJS and TEN patients were compared. The severity of the acute ocular disease and abnormal laboratory tests were not found to be the significant risk factors of late complications. CONCLUSIONS: Ocular involvement is common in SJS and TEN and can be severe and blinding. The severity of acute ocular complications does not predict late complications. The diagnosis of TEN does not imply a more severe ocular involvement or increased frequency of late ocular complications compared with SJS. Care should be taken even in mild cases. Appropriate intervention during acute ocular disease may prevent late complications.

High-dose intravenous immunoglobulin in the treatment of toxic epidermal necrolysis: a study of ocular benefits.

PURPOSE: To compare acute ocular complications of toxic epidermal necrolysis (TEN) following treatment with high-dose human intravenous immunoglobulin (IVIG) with a historical cohort not treated with IVIG. METHODS: Retrospective, historically controlled study. In all, 10 consecutive patients with TEN (treatment cohort) presenting between 1 July 2001 and 30 June 2002. Totally, 18 consecutive patients with TEN (historical cohort). SettingTan Tock Seng Hospital, Singapore. The treatment cohort received high-dose IVIG (2 g/kg body weight over 2 days). Patients' records were retrospectively reviewed for their demographic characteristics, causative drug, treatment, ocular involvement (if any, as assessed by an ophthamologist), and its severity. The historical cohort comprised patients coded with a diagnosis of TEN (ICD Code 695.1) between 1 July 1995 and 30 June 2001. RESULTS: Nine (90%) of 10 patients treated with IVIG had ocular involvement. Phenytoin was the implicated drug in three (37.5%) patients. Of the nine patients, 1 died of septic shock. Of the eight survivors, IVIG was initiated immediately upon onset of TEN as all the patients were hospitalized by the time of onset of an exanthema. Acute ocular complications were mild in two (25%) (lid oedema or mild conjunctival injection), moderate in four (50%) (pseudomembranes) and severe in two (25%) (nonhealing epithelial defect with visual loss and symblepharon). In total, 10 (55.6%) of 18 patients in the historical cohort with TEN had acute ocular involvement. Two patients died. Ocular involvement in survivors was mild in five (62.5%) cases and moderate in three (37.5%), with no severe cases. CONCLUSIONS: IVIG did not appear to reduce the severity of visually significant ocular complications. Larger studies are needed to confirm this finding.

Complete chaos in a simple epidemiological model.

A first-order difference equation which constitutes a simple model for a lethal parasite-host interaction is studied. Completing a study initiated by May and Anderson, the dynamics are shown to be completely chaotic.