This specific diagnostic term is Argyll Robertson Pupil. Hence the origin of the politically incorrect term, “prostitute’s pupil”. Historically speaking this was very commonly seen with neurosyphilis. So what does light-near dissociation mean clinically and what should be done diagnostically? There are a few entities to consider. In light-near dissociation there is slow or incomplete pupillary light reflex, but the pupil will still constrict during accommodation. In a dimly lit room have the patient look at your finger from 3-4 feet away and then move your finger towards their nose as the patient follows your finger observing the convergence of the eyes and the constriction of the pupils. Following the light response, the physician should check that the pupils constrict on accommodation. RAPD and its causes is described in more detail in another section. A swinging light test, shining light from one pupil to the next can then be done to check for a relative afferent pupillary defect (RAPD).

First watching for the direct response (constriction of the ipsilateral pupil) and next looking for the consensual response (constriction of the contralateral pupil). Shine light individually into each eye twice. The first step is to check the light reflex. Holding a pen light at a slight angle below the face allows for easy visualization of the pupils without the light hitting the retina and causing constriction of the pupils. In a dark room observe the size of the pupils. The pupil constricts (due to a similar pathway as above including the Edinger-Westphal nuclei), the lens shortens allowing the eyes to focus (due to relaxation of the zonular fibers due to action of muscles within the ciliary bodies), and the eyes converge on the object (meaning turn in via contraction of the medial rectus muscles).ĭuring the physical exam it is important to do a thorough pupillary exam as abnormal responses can be diagnostic clues to potentially serious pathology. This is what leads to direct (stimulated) and consensual (contralateral) pupil constriction.Īccommodation is slightly more complicated and actually consists of three actions. It then travels to the oculomotor nerves (CN3) and to the ciliary sphincters where it constricts both pupils. The sensory input travels through the optic nerve (CN2) to the pretectal nucleus where it then travels to both Edinger-Westphal nuclei. There are two main reasons for constriction, the first is due to stimulation by light (pupillary light response) and the second is due to accommodation or when a patient focuses on a near object.įor the pupillary light response, increased light on the retina leads to miosis or constriction of the pupil and less light leads to mydriasis or dilation of the pupil. To discuss light-near dissociation it is important to first have a discussion on the pupil itself and why it constricts. Unfortunately, many physicians do not properly asses all aspects of the acronym, so it is very possible to miss subtle changes in the pupils. PERRLA or Pupils Equal, Round, Reactive to Light and Accommodation might be the most common acronym to be seen in medical records on the physical exam.

Home / Basic Ophthalmology Review / Pupillary ExamĪuthor: Robert Henseler, 4 th Year Medical Student, Rutgers University – New Jersey Medical School

Argyll robertson pupil bilateral