CCOG for OMT 206 archive revision 206

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Effective Term:
Summer 2014 through Summer 2015

Course Number:
OMT 206
Course Title:
Diagnostic Procedures I
Credit Hours:
Lecture Hours:
Lecture/Lab Hours:
Lab Hours:

Course Description

Introduces fundamentals of diagnostic testing and techniques including: applanation tonometry, slit lamp biomicroscopy, Goldmann and automated perimetry, ocular motility and advanced keratometry. Emphases building clinical skills.

Intended Outcomes for the course

Upon successful completion students should be able to:

1. Skillfully complete patient workup in a clinical setting.
2. Accurately perform and document the biomicroscopy and visual field examination, retinoscopy and refractometry in the clinical setting.
3. Efficiently and accurately perform applanation tonometry under supervision in a clinical setting.

Outcome Assessment Strategies

At the beginning of the course, the instructor will detail the methods used to evaluate student progress and the criteria for assigning a course grade. The methods may include one or more of the following tools: examinations, quizzes, homework assignments, research papers, laboratory modules, student participation and demonstration of competency.

Course Content (Themes, Concepts, Issues and Skills)


  • Demonstrate the lacoation of the optical center of the lens.
  • Demonstrate measurement and proper recording of single vision and multifocal spectacles.
  • Demonstrate two methods of measurement of spectacles with prism.
  • Discuss the significance of vertex distance.
  • Demonstrate usage and measure base and power curves of spectacle lens using the Geneva lens clock.
  • Convert Geneva lens clock measurements into a plus cylinder spectacle prescription.


  •  Review and demonstrate Amsler grid, confrontational, tangent screen and automated visual field testing.
  •  List and describe manual techniques for testing the visual field including tangent screen, and Goldmann perimetry.
  • Demonstrate calibration of the Goldmann perimeter, including both stimulus and background.
  •  List automated methods for testing the visual field.
  • Describe when corrective lenses are required and for which portion of the Goldmann perimetry procedure.
  • Distinguish the difference between static and kinetic field testing.
  • Differentiate testing strategies for glaucoma and neurological examinations.     
  • Define minimum criteria for testing for Armaly-Drance glaucoma screening examination, including blind spot screening methods.
  •  Describe the procedure for confirming respect for the horizontal or vertical meridian.
  •  Describe screening of possible malingering patient with tangent screen and expected results.


  •   Describe two major styles of slit lamps.
  •   Define “coaxial” as it relates to the slit lamp.
  •  Differentiate “magnification” vs. “illumination” in isolating pathology with the slit lamp.
  • Describe the procedure for properly setting each eyepiece of the slit lamp microscope.
  •  List 6 “direct” and 6 “indirect” forms of illumination with the slit lamp.
  • Describe the use and technique for each of the following forms of illumination: diffuse, parallel piped, optical sectioning, tangential, conical beam, specular reflection, proximal illumination, sclerotic scatter, direct retro-illumination from the iris, indirect retro-illumination from the iris, retro-illumination from the fundus and iris tranillumination.
  • List the different filters available on the slit lamp and their usage.
  • Describe the vital dyes and their usage when used with the slit lamp including: Fluorescein, rose Bengal and lissamine green.
  • Describe when the Seidel test is used and how it is performed.
  • Describe accessory lenses available to use with the slit lamp microscope; why and how they should be used.
  • Differentiate between direct and indirect gonioscopic lenses.
  • Utilize biomicroscopy to perform and anterior segment and ocular adnexa examination.


  • Describe the differences in tonometers.
  • Outline the advantages and disadvantages of each kind of tonometer.
  • Explain how to use each tonometer.
  • Decide which instrument to use to accomplish the measurement with greatest accuracy, efficiency, and least amount of discomfort to the patient.
  • Discuss proper methods of cleaning and list 3 acceptable methods for disinfecting tonometers.
  • Discuss technique for each method of tonometry: non-contact, TonoPen, Schiotz, pneumotonometer, hand-held tonometers, MacKay-Marg and Goldmann applanation.
  • Describe the proper end point image in Goldmann applanation tonometry.
  • Describe interpretation of the measuring dial of a Goldmann applanation tonometer in recording intra-ocular pressure.
  • Describe and give the proper abbreviation of the units measured in tonometry.
  • Describe the intra-ocular changes during the systole and diastole of the heartbeat.
  • Describe the proper rotation of the tonometer prism head for patients with corneal cylinder of more than 3 diopters.
  • Demonstrate the process of checking calibration of a Goldmann applanation tonometer in all three measurement ranges.
  • Demonstrate checking calibration of TonoPen and proper measurement technique including replacement of OcuFilm tip covers.
  • Demonstrate disinfecting each instrument.
  • Perform and document applanation, non-contact, and indentation tonometry.
  • Describe how central corneal thickness relates to measurement of intra-ocular pressure readings.
  • Describe how intra-ocular pressure readings are converted for thick or thin corneas.
  • List 3 types of patients contraindicated for tonometry.  


  • State and explain the principles of and indications for retinoscopy.
  • Describe the mechanism and functioning of the streak retinoscope.
  • Describe the various types of behavior of the retinoscopic streak.
  • Explain the recording of retinoscopic results and transpose those results into sphero-cylinderical form.
  • Perform retinoscopy on the schematic eye.
  • Perform retinoscopy on the human eye.
  • Demonstrate appropriate maintenance of various retinoscopes.
  • List at least 3 types of patients for whom retinoscopy is critical because refractometry cannot be performed.
  • Describe the proper setup, with both phoropter and trial frames, for performing retinoscopy.
  • Describe the reasons for both “fogging” the fellow eye and having the fellow eye unoccluded during retinoscopy.
  • Describe proper sleeve position for both the Copeland type and Welch Allyn types of retinoscopes.
  • Describe the purpose of using a “working lens” or subtracting “working distance” from the patients retinoscopic findings.
  • List the steps performed when retinoscoping in plus cylinder.
  • Explain the use of the “double sphere” method in retinoscopy.
  • List the types of motion observed in patients with emmetropia, myopia, hyperopia and astigmatism.
  • List the types of lenses used to neutralize motion in myopes, hyperopes and astigmats.
  • Describe a method of confirming that neutrality has been achieved in retinoscopy.
  • Give estimated spherical refractive errors for patients with visual acuities of: 20/80, 20/200, 20/400, and worse than 20/400.
  • Explain how keratometry findings can help in finding proper correction of axis in retinoscopy.
  • Describe a retinoscopic reflex in patients with high refractive error.


  • Differentiate between refraction and refractometry.
  • Define emmetropia, ametropia, hyperopia, myopia and astigmatism.
  • Describe symptoms of myopes, hyperopes and astigmats.
  • Identify all knobs, dials and parts of the phoropter.
  • List the five main steps in refractometry.
  • List at least 5 “rules” to use during refractometry.
  • Describe the proper use of the Jackson Cross Cylinder in testing both cylinder axis and power (in plus cylinder).
  • Describe the “4-Step Test” for looking for cylinder power when spheres alone do not correct vision adequately.
  • Describe the astigmatic clock and its usage.
  • Describe the duochrome test and it’s usage in preventing over-minusing.
  • Describe the principle of binocular balancing and how it is performed.
  • Define “aphakia” and “pseudophakia”.
  • Describe techniques to use with aphakic patients.
  • Describe trial frames and loose lenses – distinguish how refractometry with these is different than that with a phoropter.
  • Define vertex distance and explain when/how it is measured in performing refractometry.
  • Define “Halberg Clips” and explain when/how they are used when “over-refracting”.
  • Define presbyopia and list common symptoms.
  • List estimated “adds for each age” for each group of presbyopes.
  • List the process for checking the patients “near range” with “adds” in place.
  • List three methods of measuring amplitude of accommodation.
  • Describe subjective and objective methods of measuring refractive error.
  • Explain the refinement technique using a cross cylinder lens.


  • Demonstrate motility screening tests including cover/uncover, alternate cover tests.
  • Demonstrate phoria and tropia.
  • Demonstrate Krimsky and Hirschberg estimation.
  • Demonstrate the use of the Maddox rod, Worth 4-Dot, red glass, duction and version testing.
  • Demonstrate near point of convergence/accommodation.
  • Demonstrate vergence amplitudes.
  • Demonstrate use of the Risley rotary prism.


  • Demonstrate extending the range of keratometry