Bryant states that feminine boys were not a new phenomenon at this time; however, the public emergence of adult transsexual women (male to female) in the 1950s was new and created a number of problems for psychologists, motivating some to undertake efforts at preventing their further emergence. Meyerowitz chronicles the deep disagreements which erupted between psychologists and physicians after Christine Jorgensens public gender transition, namely over whether transsexuals should be permitted to align their bodies with their inner identities or whether their inner identities must be brought in line with their bodies. At the time, transsexual women were beginning to publish first-person narratives which highlighted their awareness of their femininity at a young age and Bryant states that some clinicians and researchers thus turned their attention to feminine boys, constructing sissies as a new "medicalized patient and research population. "In 1960, Green and Money published a paper titled "Incongruous Gender Role: Nongenital Manifestations in Prepubertal Boys," detailing their observations of 5 children assigned male at birth(AMAB) who "showed incongruities in gender role", ranging from preferring to play with girls to praying God would change them into a girl. Citing that adult gay men and transgender women recollect gender incongruity in childhood, they later concluded 
early intervention is best in cases of gender incongruity and that "part of the successful rearing of a child is orienting him, from birth, to his biologically and culturally acceptable gender role.
Congenital cases may have developmental abnormality due to abnormal muscle structure, usually muscle atrophy / hypertrophy or rarely, absence of the muscle and incorrect placement. Specific & common causes include:

Superior oblique Palsy / Congenital fourth nerve palsy
Inferior oblique overaction
Browns syndrome
Duanes retraction syndrome
Double elevator palsy
Fibrosis of rectus muscle in Graves Disease (most commonly inferior rectus is involved)
Surgical trauma to the vertical muscles (e.g. during scleral buckling surgery or cataract surgery causing iatrogenic trauma to the vertical muscles).Sudden onset hypertropia in a middle aged or elderly adult may be due to compression of the trochlear nerve and mass effect from a tumor, requiring urgent brain imaging using MRI to localise any space occupying lesion. It could also be due to infarction of blood vessels supplying the nerve, due to diabetes and atherosclerosis. In other instances it may be due to an abnormality of neuromuscular transmission, i.e., Myasthenia Gravis. Treatment
In general, strabismus can be approached and treated with a variety of procedures. Depending on the individual case, treatment options include:

Correction of refractive errors by glasses
Prism therapy (if tolerated, to manage diplopia)
Vision Therapy
Patching (mainly to manage amblyopia in children and diplopia in adults)
Botulinum toxin injection
Surgical correctionSurgical correction of the hypertropia is desired to achieve binocularity, manage diplopia and/or correct the cosmetic defect. Steps to achieve the same depend on mechanism of the hypertropia and identification of the offending muscles causing the misalignment.