Swinging-flashlight test

Jump to navigation Jump to search
Swinging-flashlight test

Template:Search infobox Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]


The swinging-flashlight test is used to help a practitioner decide whether reduced vision is due to ocular disease.

Process

For an adequate test, vision must not be entirely lost. In dim room light, note the size of the pupils. After asking the patient to gaze into the distance, swing the beam of a penlight back and forth from one pupil to the other, each time concentrating on the pupillary size and reaction in the eye that is lit.

Interpretation

  • Normally, each illuminated eye looks or promptly becomes constricted. The opposite eye also constricts consensually.
  • When ocular disease, such as cataract, impairs vision, the pupils respond normally.
  • When the optic nerve is damaged, the sensory (afferent) stimulus sent to the midbrain is reduced. The pupil, responding less vigorously, dilates from its prior constricted state. This response is an afferent pupillary defect (Marcus Gunn Pupil). the opposite eye responds consensually.

References

  • Bickley L.S. 2003. Bates' guide to physical examination and history taking. 8th ed. Lippincott Williams and Wilkins, New York. pp. 169.

See also

External links

Template:Skin and subcutaneous tissue symptoms and signs Template:Nervous and musculoskeletal system symptoms and signs Template:Urinary system symptoms and signs Template:Cognition, perception, emotional state and behaviour symptoms and signs Template:Speech and voice symptoms and signs Template:General symptoms and signs


Template:WikiDoc Sources