Ditropan-associated Esotropia Dr. Elaine Wong Dr. Lionel Kowal Ocular motility clinic, RVEEH CERA, Uni Melb, RVEEH

Ditropan-associated ET  5 yo girl PMHx  Hypothyroidism – on oroxine  Enuresis HOPC  Recent onset intermittent ET  Closing L eye when drawing or reading  Recently started on Ditropan (Oxybutynin) for enuresis

presentation  VAR 6/8VAL 6/8  Near VAR 6/9 VAL 6/8  Stereopsis: Titmus fly 100”  CT: D) RET 15ΔN) RET’ 35Δ  OM: normal  Polarised 4 dot test: R suppression  Cycloplegic refraction:  R: +3.25; L

Ditropan-associated ET  After cessation of Oxybutynin  VAR 6/8VAL 6/8  Near VAR 6/6VAL6/8  CT: D) orthophoria  N) orthophoria  ELAINE : CHECK THE DATA ON THIS SLIDE PLS  Polarised 4 dot test: Fusion  Stereopsis: Titmus fly 100”

Discussion - Oxybutynin Muscarinic receptor antagonist often used for overactive bladder Muscarinic receptor antagonist often used for overactive bladder COMMONLY PRESCRIBED COMMONLY PRESCRIBED Anticholinergic systemic SE Anticholinergic systemic SE Ocular effects Ocular effects Ciliary ganglion – accomodationCiliary ganglion – accomodation Pterygopalatine ganglion – lacrimationPterygopalatine ganglion – lacrimation

Ocular side-effects of tolterodine and oxybutynin, a single-blind prospective randomized trial Altan-Yaycioglu et al. Br J Clin Pharmacol 95:5,  52 patients, 104 eyes  Randomised into Tolterodine 2mg bd – 28 pts Tolterodine 2mg bd – 28 pts Oxybutynin 5 mg tds – 24 pts Oxybutynin 5 mg tds – 24 pts  All examined by ophthalmologists Schirmer’s Schirmer’s Accomodative amplitude Accomodative amplitude Pupillary diameter PD Pupillary diameter PD

Discussion TolterodineOxybutynin Accom amp (DS)2.06 to to 1.80 ( p = 0.07)(p = 0.003) Schirmer’s (mm)12.82 to to (p = 0.698)(p = 0.342) PD bright (mm)1.94 to to 2.08 (p = 0.174)( p = 0.953)

Discussion  In this case Oxybutynin Impairs accommodation Impairs accommodation Pre-existing moderate uncorrected + Pre-existing moderate uncorrected + To accommodate sufficiently to see, the pt converges, and the CA/C ratio then generates accommodation To accommodate sufficiently to see, the pt converges, and the CA/C ratio then generates accommodation hence ESOTROPIA!!! hence ESOTROPIA!!! ? Is Tolterodine (Detrusitol) safer ? Is Tolterodine (Detrusitol) safer

Ditropan  Frequently prescribed  Has never been described as cause of ET!  Likely to cause  accommodation and  convergence  Dit + hyperopia likely to cause ET  Almost certainly underrecognised