Influencing factors of stereopsis function after strabismus operation / 国际眼科杂志(Guoji Yanke Zazhi)

@#Proper assessment of the establishment of stereopsis after strabismus surgery continues to be challenging for the strabismus surgeon. In view of the stereopsis, the timing of surgery for strabismus has been controversial because of concerns that it may result in an overcorrection or lateness. Recent literature on the strabismus surgeon has shown that the establishment of postoperative stereoscopic vision is closely related to the age of onset, types of strabismus, course of disease and ocular deviation. This review will summarize the recent points as below.

Tonic inward and downward deviation of the eye

BACKGROUND: Tonic inward and downward deviation of the eyes ('peering at the tip of the nose') is regarded as a unique feature of thalamic hemorrhage, but the mechanisms of this ocular finding remain obscure. OBJECTIVE: To report on four patients who showed tonic inward and downward deviations of the eyes from either brainstem or thalamic lesions, and to discuss the possible mechanisms involved. DESIGN: Case report SETTING: Secondary and tertiary referral hospitals RESULTS: One patient developed alternating esotropia with downward ocular deviation from thalamic hemorrhage compressing the midbrain. Two patients showed multiple infarctions in the territory of the posterior circulation with or without the involvement of the thalamus. Another patient had lateral pontine hemorrhage extending up to the midbrain tegmentum. Ocular bobbing preceded or accompanied tonic ocular deviation in three patients. CONCLUSION: Tonic inward and downward deviation of the eye may develop in thalamic or brainstem lesions. Irritation or destruction of the neural structures involved in the vergence and vertical gaze may cause this ocular sign in mesodiencephalic lesions. Skew deviation and esotropia from abduction deficit may be involved in some patients. Ocular bobbing and tonic downward deviation may share a common pathophysiology.

Angle Kappa Measurement with Slit Lamp Biomicroscope

PURPOSE: There has been a difficulty in measuring angle kappa because special instrument was required. To measure the angle kappa conveniently, we designed a new method using slit lamp biomicroscope. METHODS: We measured the angle kappa in 124 eyes of 62 patients with newly designed method and compared the measurement by new method with those by T-shape ruler or the major amblyoscope. RESULTS: We found the average angle kappa was +3.12 degrees by slit lamp, +2.85 degrees by major amblyoscope and +3.04 degrees by T shape ruler method. There was no significant difference between slit lamp and either major amblyoscope method (p=0.48) or T shape ruler (p=0.18). CONCLUSIONS: The new method of measuring angle kappa using slit lamp biomicroscope seemed to be a convenient and relatively accurate method for measuring of angle kappa and appeared to be beneficial in measurement of ocular deviation.