An: 2019, Nr.3, Articol Nr. 8
ANATOMICAL DESCRIPTION OF THE ZINN RING AS AN IMPORTANT WAY OF SUSPENDING THE EYE
Gabriela Diana Ivascu (Oprea) - University of Medicine and Pharmacy „Carol Davila“ Bucharest, Doctoral School
C.M. Pantu, F.M. Filipoiu, St. Oprea - University of Medicine and Pharmacy „Carol Davila“ Bucharest, Discipline of Anatomy
E. Ungureanu - University of Medicine and Pharmacy „Carol Davila“ Bucharest, Discipline of Opthalmology
Al.V. Breazu - University of Medicine and Pharmacy „Carol Davila“ Bucharest, Doctoral School; Discipline of Anatomy
ANATOMICAL DESCRIPTION OF THE ZINN RING AS AN IMPORTANT WAY OF SUSPENDING THE EYE (Abstract): Zinn’s ring is a dense fibroconjunctive structure that covers like sheath the optic nerve before it enters the optic hole. It is recognized as being the place of insertion for the extrinsic muscles of the eyeball. So the a good knowledge and understanding of its anatomy can be very useful for the ophthalmologists, especially for those specialized in strabology. We performed dissections on 6 formolized corps from the UMF Carol Davila anatomy discipline laboratory. After the removal of the skull and brain, the roof of the orbit was resected. The superficial elements were carefully identified and separated. Zinn’s ring was contoured on its distal edge, and later the tendinous cuff content was opened. After removing the roof of the orbit through an intracranial approach we obtain an overview of the orbital content. This visceral package is centered by the optic nerve, surrounded mainly by the extrinsic muscles of the eyeball. At the apex of the orbit we identify: the Zinn’s ring, which unlikely to the name has more cylindrical shape than a ring one. It covers like a sleeve the last 1.5cm of the optic nerve before it leaves the orbit. We inserted an image  from the past where we can see that at that time it was considered that the upper eyelid elevator muscle and the upper oblique originate outside the tendinous ring. Our images show with no denial that nothing is inserted outside the tendinous ring. Everything is under the periorbite - the structure that continues the ring to anterior. Basically, the external blade of the dura mater penetrates into the optic canal with a disposition of funnel around the optic nerve, its fibrous sheaths and ophthalmic artery. The funnel canal becomes the common tendon tunnel, which widens as we have shown, to the previous one. And the insertions of the two muscles are in the common tendinous ring. Advancing with the dissection we made a meticulous description of the Zinn’s ring and the elements in relation with it. One of our conclusion was that the continuity with the dura mater indicates that in reality the communication of the orbit with the endobase is made through the Zinn ring.
Key words: ZINN’S RING, EXTRINSIC MUSCLE OF THE EYEBALL, STRABISM, EYE MOTILITYFull text