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CCOG for OMT 207 Fall 2022

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Course Number:
OMT 207
Course Title:
Diagnostic Procedures II
Credit Hours:
4
Lecture Hours:
30
Lecture/Lab Hours:
0
Lab Hours:
30

Course Description

Presents the principles of advanced visual field examination with emphasis on Goldmann Perimetry. Covers the principles and techniques of exophthalmometry, color and function tests, contact lens fitting, ocular motility and echography. Focuses on skill development, and increasing speed and accuracy.

Intended Outcomes for the course

Upon completion of the course students should be able to:

  1. Accurately perform manual perimetry in the clinical setting.
  2. Perform basic evaluation of contact lens fit, patient education regarding insertion, removal, care and handling of contact lenses in the clinical setting.
  3. Accurately measure axial length of the eye and calculate intraocular lenses' power in preparation for surgery.
  4. Perform a variety of ancillary diagnostic tests in the clinical setting including color vision and tear function tests.

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 and student participation.

Course Content (Themes, Concepts, Issues and Skills)

ADVANCED VISUAL FIELDS

  • Name and describe the anatomical structures of the visual pathway.
  • Define coordinates of the visual field, including radial meridians and circles of eccentricity.
  • Discuss the island of vision analogy.
  • Define foot-candle.
  • Define visual field terminology including:  isopters, threshold, suprathreshold, apostilb, decibel.
  • Define depression, general defect, and focal defect of the visual field.
  • Define quadrant, sector, hemi, altitudinal, bitemporal, nasal step, homonymous, congruous, incongruous, ipsilateral, and contralateral as they apply to depressions of the visual field.
  • Define scotoma and list the 5 criteria for exploring scotoma of the visual field.
  • Define central, pericentral, paracentral, cecal, centro-cecal as they apply to scotomas of the visual field.
  • List the sequence of the visual pathway from the retina to the visual cortex in correct order. 
  • Relate visual field loss to specific ocular dysfunction/pathology.
  • Calibrate the Goldmann perimeter.
  • Perform a Goldmann visual field examination with emphasis on correct procedure for selecting stimulus and correcting lens power, plotting isopters, finding defects and investigating visual field loss.
  • Describe common visual field artifacts and their causes.
  • List common visual field defects from: retinal disease, optic nerve disease/glaucoma and neurological disease.

MOTILITY

  • Define fusion, diplopia and suppression.
  • Describe use of the Maddox rod, Worth 4-dot, red glass and Bagolini lenses in testing for fusion.
  • Perform cover/uncover test, alternate cover test, Krimsky and Hirschberg tests.

ECHOGRAPHY

  • List classifications of ultrasound
  • Explain terminology related to ultrasound including signal, amplitude, transducer, attenuation, reflection, gates, spikes, A-constant, and immersion.
  • Describe clinical applications of diagnostic ultrasound
  • Demonstrate proper maintenance of ultrasound equipment
  • Define corneal thickness and list the steps necessary to perform corneal pachymetry
  • Define standardized echography
  • Calculate an accurate IOL lens power
  • Demonstrate proper labeling of echograms
  • State the effect of corneal power, lens power and overall length of the eye on IOL calculations
  • Distinguish contact A-scan from Immersion A-scan
  • List methods of performing diagnostic B-scans
  • List methods available to document ultrasound images
  • List steps necessary for performing Laser Interferometry axial length measurement. (IOL Master)
  • Demonstrate axial length measurements with an IOL Master
  • Define and describe wave front diagnostics
  • Compare and contrast keratometry readings to corneal topography readings
  • Corneal sensitivity testing
  • Contact lens slit lamp exam (pre and post fitting)

CONTACT LENSES

  • Take measurements of contact lenses (diameter, base curve, power and center thickness)
  • Describe patient instruction for cleaning, inserting and removing contact lenses.
  • Fit a contact lens on a given patient.
  • Evaluate the fit of a contact lens and describe what changes to the fit may be necessary.
  • Modify a rigid lens diameter and power.
  • Demonstrate corneal topography.
  • Define Placido disc and its concept: reflection of rings that are closer together or further apart.
  • Correctly identify the patterns of corneal topography consistent with:
    • with the rule astigmatism
    • against the rule astigmatism
    • irregular astigmatism
    • kerataconus
    • LASIK
    • Radial Keratotomy
    • Penetrating keratoplasty

INSTRUMENT MAINTENANCE

  • Change bulbs on the lensometer, slit lamp, Goldmann Perimeter, keratometer, retinoscope, and acuity projector.
  • Calibrate the Goldmann tonometer, lensometer, keratometer, IOL Master, and acuity projector.


EXOPHTHALMOMETRY, COLOR VISION, TEAR FUNCTION

  • Perform measurement of proptosis using a Hertel exophthalmometer.
  • Demonstrate color vision testing using Ishihara test plates.
  • Demonstrate color vision testing using the D-15 test.
  • Name alternate methods of color testing.
  • Take a history relevant to identifying a possible "dry eye" patient.
  • List the steps to perform Schirmer Tear Test I and II.
  • Rose Bengal.
  • Define and demonstrate a tear film "breakup time" test (BUT).
  • Corneal sensitivity testing.