Clinical hints for Your approach for examining the pupils

Light response pathway of Clinical hints for Your approach for examining the pupils

Optic nerve >EWN ( bilaterally)> 3rd nerve ( inferior division> ciliary ganglion >short ciliary nerves > pupillary sphincter> constriction 

Near response pathway of Clinical hints for Your approach for examining the pupils

Visual association area ( area 19)> frontal eye field area > EWN> 3rd nerve to > ciliary ganglion ( short ciliary nerves ) and MR muscle ( nerve to MR ) > constriction, accommodation and convergence 

Light-near dissociation of Clinical hints for Your approach for examining the pupils

• dorsal midbrain pathology 
• reduces the response to light 
• preserving the response to near. 
• thought to be due to the fact that the near pathway is placed ventral to the more dorsal pretectal nucleus serving the light pathway.

Clinical hints for Your approach for examining the pupils power point presentations: 

Pupil ( Examining the pupils )

https://www.slideshare.net/Juliebebot/pupil

The pupillary pathway and its clinical aspects ( Examining the pupils )

https://www.slideshare.net/laxmieyeinstitute/the-pupillary-pathway-and-its-clinical-aspects

1. The Pupillary Pathway and its Clinical Aspects
2. Outline  Anatomy  Physiology  Clinical Examination  Afferent Pathway defects  Efferent Pathway defects
3. The Afferent Pathway Optic tract Nasal Fibers decussate in optic chiasm Travels centrally along the optic nerve Ganglion cells Rods and cones AND Melanopsin Retinal Ganglion cells
4. The Afferent Pathway(contd.) The Accessory motar nuclei of EW nucleus New relay fibers partially cross over Pretectal Nucleus Midbrain from Lateral side of Superior colliculus
5. The Efferent Pathway Located inferiorly as it enters the orbit Passes laterally to petroclinod ligament and dorsum sellae Lie on the superficial dorsomedial aspect as it leave the brain stem The axons of the EW nucleus extend into the III n.
6. Inferior division of III n. Ciliary Ganglion Via short Ciliary nerves Sphincter Pupillae
7. Sympathetic Pathway
8. Pathway of Convergence Reflex Fibers form Medial Rectus m. via III n. Mesencephalic n. of V n. Convergence Center in Tectal or Pre Tectal Region EW Nucleus Efferent fibers travel along III n. Relay in Accessory Ganglion Sphincter Pupillae
9. Pathway of Accommodation Reflex Retina Via Optic nerve, Chaisma Optic Tract Lateral Geniculate Body Striate Cortex From the Para Striate Cortex Via Occipitomesencephalic Tract and Pontine center EW Nucleus Via III n. to Sphincter Pupillae
10. Function of the Pupil Functions:  Control in retinal Illumination  Reduction in optical aberration  Depth of Focus Clinical Importance  Objective indicator of Light Input  Anisocoria  Pharmacological Indicator  Indicated level of wakefulness
11. The Light Reflex  The light reflex consist of simultaneous and equal constriction of pupils in response to stimulation of one eye by light  Pupil constriction is elicited with extremely low intensities and is proportional within limits to both intensities and duration of stimulus.
12. Direct and Consensual Reflex
13. Near Reflex  Two components: 1. Convergence Reflex: Convergence of visual axis and associated constriction of pupil 2. Accommodation Reflex: Increased accomodation and associated constriction of pupil  Near Reflex Traid consists of: – Increased Accommodation – Convergence of Visual Axis – Constriction of pupils  Both neurons in the EW nucleus stimulated from SUPRANUCLEAR level.

Abnormal Pupil Reactions ( Examining the pupils )

https://www.slideshare.net/hatlanalhatlan/ophtha-43074620