Comitant Hypertropia Etiology a. Originally incomitant vertical strabismus (usually congenital which has become comitant with time). b. Abnormalities of insertion or attachments of vertical muscles. Asymmetry of orbit or displacement of the globe. (Hypoglobus) Characteristics a. Frequently vertical deviation is associated with horizontal strabismus, but vertical component is the primary factor. b. Deviation is the same with either eye fixing and in all directions of gaze. c. Amblyopia or suppression frequently present. d. ARC may be present due to a constant angle. e. Compensatory head posture frequently present (retained after spread of comitance). Treatment a. Orthoptics ineffective. b. If fusion present either on the Synoptophore or with Fresnel prisms (check monthly and gradually reduce prisms). Treat amblyopia if present in children and place Fresnel prism in front of dominant eye, non-dominant eye in adults. c. If reduction of prism is unsuccessful ground in prisms or surgery. d. If no fusion surgery if cosmetically unacceptable. – Incomitant Hypertropia 1. Superior Oblique Palsy Example (Left Superior Oblique – Palsy) Etiology: Paretic in origin. Superior oblique trial is the most commonly seen paretic vertical muscle. b. Causes: Vascular disease, inflammation, viral, trauma, most frequently congenital. c. Characteristics i. Head-tilt most characteristic; head tilted to side opposite the paretic muscle. ii. If head forcibly tilted to side of paralyzed eye, the eye
Comitant Hypertropia Etiology a. Originally incomitant vertical strabismus (usually congenital which has become comitant with time). b. Abnormalities of insertion or attachments of vertical muscles. Asymmetry of orbit or displacement of the globe. (Hypoglobus) Characteristics a. Frequently vertical deviation is associated with horizontal strabismus, but vertical component is the primary factor. b. Deviation is the same with either eye fixing and in all directions of gaze. c. Amblyopia or suppression frequently present. d. ARC may be present due to a constant angle. e. Compensatory head posture frequently present (retained after spread of comitance). Treatment a. Orthoptics ineffective. b. If fusion present either on the Synoptophore or with Fresnel prisms (check monthly and gradually reduce prisms). Treat amblyopia if present in children and place Fresnel prism in front of dominant eye, non-dominant eye in adults. c. If reduction of prism is unsuccessful ground in prisms or surgery. d. If no fusion – surgery if cosmetically unacceptable. Incomitant Hypertropia 1. Superior Oblique Palsy – Example (Left Superior Oblique Palsy) Etiology: Paretic in origin. Superior oblique is the most commonly seen paretic vertical muscle. b. Causes: Vascular disease, inflammation, viral, trauma, most frequently congenital. c. Characteristics i. Head-tilt most characteristic; head tilted to side opposite the paretic muscle. ii. If head forcibly tilted to side of paralyzed eye, the eye trial
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