Ans. b (Schirmer test) (Ref. Khurana ophthalmology 3rd ed., p. 300)Tests of tear secretion can thus be separated into those that test basal tear production (from the glands of Krause and Wolfring) and those that test reflex tear production (from the primary lacrimal gland). The Schirmer test is simple, practical and semiquantitative method of measuring both reflex and basal secretions. It is a commonly used initial screening procedure for Sjogren's Syndrome (Keratoconjunctivitis Sicca). It assesses the function of the major lacrimal glands, which are responsible for reflex tearing in response to stressful situations such as the presence of a foreign body. Reflex tearing is stimulated by inserting a strip.MEASURING THE ANGLE OF DEVIATION# Diagnosis of heterophoria/latent strabismus depends on the abolishing fusion so that, with its control, the eyes assume their position of rest.# Several Tests are Available for Assessing This:- Cover test- Madox rod test:# The rod is held in front of the eyes, image of highest point close to eye become dissimilar and fusion becomes dissociated.# Tests performance at 6 meter and 35 cm distance.- Maddox wing test (amount of phoria for near - at a distance of 33 cm) can be measured.- Prism vergence test- Synaoptophore# Exact measurement of the angle of deviation is crucial to prescribing the proper prism correction to compensate for the angle of deviation and to the corrective surgery that usually follows. A measurement error may lead to undercorrection or overcorrection of the angle of deviation during the operation.# Example: Esotropia of -h 15 degrees is corrected by shifting the medial rectus 4.0 mm posteriorly and shortening the lateral rectus 5.0 mm.# The angle of deviation is measured with a cover test in combination with the use of prism lens of various refractive powers. The patient fixates on a certain point with the leading eye at a distance of 5 m or 30 cm, depending on which angle of deviation is to be measured. The examiner places prism lens of different refractive power before the patient's deviant eye until the eye no longer makes any adjustment. This is the case when the angle of deviation corresponds to the strength of the respective prism and is fully compensated for by that prism. The tip of the prism must always point in the direction of deviation during the examination.# The Hirschberg test, also Hirschberg corneal reflex test, is a screening test that can be used to assess whether a person has strabismus. It makes use of the first captoptric image which is located on the anterior corneal surface for measuring ocular deviation. This image is also used for keratometry.FeatureConcomitant (Aparalytic)Paralytic (Nonconcomitant)ONSETSuddenInsidiousCAUSEDevelopmentalAquiredAGEInfants and childrenAdultsDIPLOPIA+NoHEAD POSTURENormalAbnormalFALSE PROJECTIONNo+ANGLE OF SQUINTConstant in all directions of gazeVariable angle of squintOCULAR MOVEMENTSNormalRestrictedANGLE OF DEVIATIONSecondary angle of deviation = primary angleSecondary angle > primaryAMBLYOPIA+NoRxGood surgical resultsNot satisfactory/contraindicatedEducational Points:Dry Eye: Sicca Syndrome# Complex qualitative and quantitative disorders of the production and surface adhesion of the tear film.# Etiology/ pathogenesis- Multifactorial, caused by ophthalmological and general diseases and by exogenous factors.# Clinical features- Dryness, sensation of pressure, pain, burning, scratching, foreign-body sensation, photophobia, lid swelling, corneal edema, corneal epithelial filaments, conjunctival folds parallel to the lid margins (LIPCOF), tear meniscus irregular and/or i< 0.2 mm.# Diagnosis- The diagnosis is made clinically and by means of tests, including the Schirmer test < 10 mm/5 min, Jones basal secretion test < 10 mm/5 min, break-up time < 10 s.# Treatment.- Tear substitute, moisture chamber, glasses with side protection, punctum plug.- Treatment of the underlying disease.- Reduction in exogenous factors (smoke, dust, night work, etc.).