Keratoconus is an ectasia in which progressive thinning and cone-shaped distortion of the cornea result in worsening vision through increasing myopia and astigmatism. Age at diagnosis is usually between 15 and 30 years however it has been suggested that keratoconus is often more advanced if first diagnosed in childhood and progresses more quickly. The estimated prevalence of keratoconus is 1.38 per 1000 population (2). Risk factors include family history of keratoconus,  eye rubbing and atopic conditions. Patients may experience a reduction in visual acuity and distortion of the visual field. Keratoconus is diagnosed through keratometry, the measurement of the curvature, thickness and steepness of the cornea with computerised corneal topography.

A 61-year-old man presented with a 1-day history of right eye pain, right periorbital swelling, and painful diplopia upon right gaze. He was triaged as having Orbital Cellulitis in the emergency room and was given intravenous metronidazole and ceftriaxone. The patient has a medical history of Type 2 diabetes, right subclavian thrombosis, and Lyme disease, for which he was treated with Doxycycline and Rifampicin. He also has colour blindness and a raised immunoglobulin level, as well as a history of soft tissue thickening and acute inflammatory changes in the right periorbital region. Upon examination, the patient's visual acuity was 6/9 in both eyes, and the right eye showed swelling and tenderness at the superior and inferior margins, chemosis, and restriction of left abduction and upgaze. Blood tests showed elevated CRP levels and a positive rheumatoid factor.

This article aims to improve junior doctor’s ability to assess and manage patients presenting with diplopia.  Diplopia is an important sign to be able to recognise, often being the first manifestation of a serious systemic, muscular or neurological disorder.

Sjogren’s syndrome (SS) is a chronic systemic autoimmune disorder which predominantly affects the salivary and lacrimal glands (exocrine glands) resulting in presentation of dry eyes (keratoconjunctivitis sicca) and dry mouth (xerostomia), collectively known as sicca symptoms. Although ren SS primarily affects glands, in some cases there is extra-glandular involvement indicating an autoimmune response can occur in other organs and tissues. SS is categorised into primary, when symptoms occur in isolation, or secondary, when symptoms occur in conjunction with another autoimmune disorder such as rheumatoid arthritis or systemic lupus erythematosus.

Moebius syndrome is a rare congenital neurological disorder whereby there is an underdevelopment or absence of cranial nerve VI (abducens) and cranial nerve VII (facial), leading to weakness or paralysis of facial and extraocular muscles. Abnormalities can also occur in other cranial nerves including the 3rd, 5th, 8th, 9th, 11th and 12th. This article will focus upon the ocular manifestations of Moebius syndrome.