Final answer:
The first pre-op assessment for a child with congenital ptosis involves the evaluation of eyelid position and function. Subsequent assessments include visual acuity, ocular motility, and tear production to plan appropriate treatment.
Step-by-step explanation:
The first pre-operative assessment done for a child with congenital ptosis is the evaluation of eyelid position and function. This initial step is crucial to understand the degree of the ptosis and its effect on vision, which can inform the necessity and urgency of intervention. It is also important to ensure that the ptosis is not affecting the child's visual development, which could lead to amblyopia ("lazy eye"). Following the evaluation of eyelid position, other assessments such as measurement of visual acuity, examination of ocular motility to check for disorders like internuclear ophthalmoplegia, and assessment of tear production to ensure normal lubrication of the eye can be performed. These assessments help in establishing a comprehensive understanding of the child's ocular health and in planning the appropriate surgical or medical treatment.