Strabismus - Types and Treatment MCQs

A history of contact lens usage and a corneal ulcer not responding to standard treatment ( antibiotics and cylcoplegics ) suggest acanthamoeba ulcer. Reference: Parson’s diseases of the Eye-Chap 12 – Diseases of Cornea.

A keratoprosthesis is a device designed to replace the cornea. Unfortunately, an ideal keratoprosthesis has not yet been devised. Implantation of a keratoprosthesis is considered only as a last resort where penetrating keratoplasty is not possible or has repeatedly failed. Implantation of a keratoprosthesis is reserved for bilaterally blind patients suffering from severe ocular surface disorders such as following chemical burns, Stevens–Johnson syndrome, severe dry eyes and recurrent graft rejections. Preoperative prerequisites include a minimum vision of light perception and absence of gross posterior segment disorders as evaluated by ultrasonography. Advanced keratoconus: first line of treatment : keratoplasty Fungal endophthalmitis: requires vitrectomy, not keratoprosthesis Reference: Parson’s diseases of the Eye-Chap 12 – Diseases of Cornea

Treatment of Candida endophthalmitis includes: Antifungal treatment : Agent is decided based on culture sensitivity. Intravenous amphotericin-B in combination with oral flucytosine is given, but resistance is a concern. Voriconazole orally or intravenously has a broad spectrum of antifungal action with low reported resistance and high ocular penetration; adjunctive intravitreal treatment may be given(100 µg in 0.1 ml), with serial injections probably needed. Pars plana vitrectomy should be considered at an early stage, especially for severe or unresponsive disease. Along with providing a substantial culture specimen, it reduces fungal and antigen load, facilitates therapeutic agent penetration and clears the ocular media. Reference: Kanski, 7th Edition, Pg no. 454.

Severe non proliferative diabetic Retinopathy Indications of treatment in DR PDR NPDR with CME Reference: parson's 22/e section IV chapter 20. pg 312-315

Guanethidine (10%) eye drops is useful in decreasing lid retraction in Thyrotoxic ophthalmopathy. It is an adrenergic neuron blocker which acts by inhibiting the release of noradrenaline in response to nerve stimulation.

Malignancy should be considered in patients with blood-tinged tears. Biopsy is necessary to establish the diagnosis. Probing or balloon dacryoplasty would fail to establish the diagnosis, and dacryocystorhinostomy could spread the tumor. Reference: Kanski 8th edition/65

Dacryocystitis with localized abscess is best treated with systemic antibiotics and prompt drainage of the abscess. Dacryocystorhinostomy surgery will accomplish drainage, but often cannot be performed in a timely fashion, and can be technically challenging due to local cellulitis and the possibility of rupture and fistulization. Probing is likely to damage the inflamed canaliculi or the valve of Rosenmuller, and topical antibiotics are inadequate. Dacryocutaneous fistula is an undesired outcome. Reference: Kanski 8th edition/75

Strabismus or any ocular deviation may result in diplopia, but the individual undertakes certain adaptations to overcome this diplopia. The compensatory mechanisms may vary according to the type of Diplopia and the age of individual. Reference: Yanoff and Duker, 4th edition, Pg no. 1225.