superior oblique muscle    n. A muscle with origin above the medial margin of the optic canal, with insertion by a tendon passing through the trochlea to the sclera between the superior rectus and lateral rectus muscles, with nerve supply from the trochlear nerve, and whose action directs the pupil of the eye downward and outward.     "superior oblique muscle." The American Heritage Stedman's Medical Dictionary. Houghton Mifflin Company, 2002. Answers.com GuruNet Corp. 07 Jul. 2005. http://www.answers.com/topic/superior-oblique-muscle superior oblique muscle   The superior oblique muscle is a muscle in the orbit that causes the eye to look downwards when it is already directed medially (looking towards the nose).  It is the only muscle supplied by the trochlear nerve. The superior oblique loops through a pulley like structure (the trochlea) to get the desired movement.     "superior oblique muscle." Wikipedia. Wikipedia, 2005. Answers.com GuruNet Corp. 07 Jul. 2005. http://www.answers.com/topic/superior-oblique-muscle  Here are SOM related links to abstracts, articles and other citations of material that are informative. Please share these references with your doctor.  It is important to note that these resources are here only because the sources have been generous in giving us permission to link to the information.  Many resources do not allow us to link directly to the document, but permit a link to their main/home page.  In those cases, instructions will accompany the link information.  For those of us with dial-up connections, this can certainly be more work, but it cannot be avoided. Visuals:  Videos, diagrams, illustrations This link to RootAtlas.com is a video of a patient with SOM.  If you have dial-up, the wait is considerable. http://www.rootatlas.com/wordpress/video/582/superior-oblique-myokymia-video/ EyeTec.Net This is their main page, from which you can find some great information. http://www.eyetec.net/index.htm This is the link to the page for information on the six extraocular muscles of the eye.  Fabulous information and illustrations.  An absolute must read for everyone. http://www.eyetec.net/group6/M27S1.htm#The%20Superior%20Oblique  University of Utah The Neuro-Ophthalmology Virtual Education Library/NOVEL Our thanks to MS. Lombardo, who generously permits this link.  We will not deeplink to the information, so please follow the instructions to find this informative and excellently prepared animation. The page on which the link can be found is the NANO Curriculum Outline: http://library.med.utah.edu/NOVEL/NOVEL_outline.html Please scroll down, approximately 2/5 of the way into the page, under ....H.Nystagmus and disorders of ocular stability ....... 7.Ocular oscillations ............a.Superior oblique myokymia (Click at this line.) On the next page that comes up, just click on the image of the eye to get to the narrated animation.  The next page has an assortment of video choices.  I chose the second one, Streaming Windows Media: mms://ecclesvideo..., and it displayed in my computer's media player.  Totally cool.When you have some time to spare, this site is full of information and animations that simply aren't available anywhere else.  They have done an amazing job here, and it really is worth your time. emedicine August 2005 Dr. Edsel Ing This is a great article to help you understand the examination process and be a better health consumer.  No images, but I didn't know where to put this. http://www.emedicine.com/neuro/TOPIC478.HTM