June 1984
Volume 25, Issue 6
Articles  |   June 1984
The effect of Timolol Maleate on tonic accommodation, tonic vergence, and pupil diameter.
Investigative Ophthalmology & Visual Science June 1984, Vol.25, 763-770. doi:
  • Views
  • PDF
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      B Gilmartin, R E Hogan, S M Thompson; The effect of Timolol Maleate on tonic accommodation, tonic vergence, and pupil diameter.. Invest. Ophthalmol. Vis. Sci. 1984;25(6):763-770.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements
This content is PDF only. Please click on the PDF icon to access.

The beta-adrenoceptor antagonist Timolol Maleate (0.5%) was employed topically to determine whether the resting (or "tonic") position of accommodation is a consequence of steady-state equilibrium between parasympathetic and sympathetic innervation of the ciliary muscle. Ten subjects were used, eight men and two women, with an age range of 19-37 (mean = 23.2). All subjects wore an optimum refractive correction giving visual acuities of 20/20 or better. Darkroom measurements of tonic accommodation (TA), tonic vergence (TV), and pupil diameter were determined with a Badal laser optometer , a nonius alignment device and infra-red photography, respectively. Far and near points of accommodation and oculo-motor balance tests were determined by standard optometric techniques and intraocular pressure (IOP) was measured by applanation tonometry. Both TA (mean = 1.66 D) and TV (mean = 2.10 deg) assumed intermediate resting positions in the absence of visual stimulation. A double-blind protocol between Timolol and Saline demonstrated a mean myopic shift in TA of +0.85 D over 40 min with Timolol. All other experimental parameters, apart from IOP, were unaffected by Timolol. It is concluded that sympathetic innervation to the ciliary muscle plays a significant role in determining the TA position and that this innervation is mediated by inhibitory beta adrenoceptors.


This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.