单眼上转不足的临床研究和治疗进展

The progress of clinical research and treatment of monocular elevation deficiency

单眼上转不足(MED)是由麻痹、限制或混合因素引起眼球上转功能缺陷,患眼向正上、鼻上和颞上方运动均受限,常伴下斜视和上睑下垂,既往又称为双上转肌麻痹(DEP)。除了负责上转的肌肉麻痹,下直肌限制和核上性病变也可参与其发病。Knapp术曾是最常用的MED术式。但当存在下直肌限制时,需首先减弱下直肌,再分期行Knapp术以避免眼前节缺血的发生,因而促生了其他的改良手术方式,如单条外直肌或内直肌转位术、部分肌腱转位术以及肌腹转位术等。根据麻痹或限制的病因进行MED的分型鉴别,对于制定合适的手术方案是非常必要的。本文对MED的临床特征、分型以及可供选择的手术方案进行综述,以期为临床研究和治疗提供参考。

Monocular elevation deficiency(MED)is a functional defect in upward eye movement caused by paralysis,restriction,or a combination of factors.The affected eye experiences limited movement in the upward,nasal,and temporal directions,often accompanied by downward deviation and ptosis.Previously known as double elevator palsy(DEP),MED can result from muscle paralysis responsible for upward movement,restriction of the inferior rectus muscle,or lesions in the supranuclear pathway.The Knapp procedure was once the most commonly used surgical approach for MED.However,in cases involving restriction of the inferior rectus muscle,a staged approach combining inferior rectus muscle weakening and subsequent Knapp procedure is necessary to avoid anterior segment ischemia.This has led to the development of alternative surgical techniques,such as single-rectus muscle transposition,partial tendon transposition,and muscle belly transposition.Differentiating MED subtypes based on the underlying paralysis or restriction etiology is crucial for determining the appropriate surgical plan.This review article summarizes the clinical features,classification,and available surgical options for MED,aiming to provide valuable insights for clinical research and treatment.