Fresnel prism in Paralytic strabismus

Kim, Seong Ju; Park, Yeoung Geol

Abstract

We performed clinical evaluations on 26 patients who were prescribed glasses with full correction and Fresnel prism for correction of abnormal head posture and/or diplopia due to incomitiant paralytic strabismus. There were 12 cases(46.2%) of superior oblique muscle palsy and 8 cases(30.8%) of lateral rectus palsy in order. Trauma was the most common cause, but non-traumatic cases were mostly caused by vascular disease of diabetes mellitus and/or hypertension. Abnormal head posture with diplopia and/or dissociated diplopia may be one of the causes of less satisfaction level than interval of prescription of Fresnel prism. Decreased visual acutiy happened when prescribed above ten prism prescription on one eye, and patients accepted with more ease when prescription wasdivided on both eyes, in spite of low prism power. We concluded that it is necessary to explain dimness due to decreased visual acuity when above ten prism power prescription is given on one eye even though prism was more effective method for diplopia gteatment.