Education

Case Report: Case 15

Case Presenters

Dr. Ramesh Kekunnaya has received his basic medical training from Karnatak Medical College, Hubli and specialized in ophthalmology from Government Medical College, Mysore, India in 1999. He completed a comprehensive ophthalmology fellowship (with special focus on Strabismus and Neuroophthalmology) at the L. V. Prasad Eye Institute (LVPEI), Hyderabad followed by a Pediatric Ophthalmology & Strabismus Fellowship (AAPOS accredited) at Jules Stein Eye Institute, University of California, Los Angeles, USA. He also had a short stint at the Moorfield’s Eye Hospital and the Great Ormond Street Hospital for children, London as a part of ICO fellowship. Dr. Kekunnaya is currently the Head of Pediatric Ophthalmology, Strabismus and Neuroophthalmology at Child Sight Institute and Jasti V. Ramanamma Children’s Eye Care Center, LVPEI, Hyderabad
and Clinical Assistant Professor Case Western Reserve University Cleveland, Ohio. He is also in charge of the Paediatric Ophthalmology and strabimus fellowship program. He is a member of the American Academy of Pediatric Ophthalmology and Strabismus (AAPOS), World Society for Pediatric Ophthalmology & Strabismus (WSPOS) and American Academy of Ophthalmology (AAO). He is an Executive Bureau member of WSPOS and a member of the Professional Education Committee of AAPOS. Dr. Kekunnaya has presented at various international and national meetings. He was a recipient of
the prestigious ‘Achievement award’ from AAO in 2012; in addition to receiving the ‘International Scholar Award’ from AAO in 2014 and the ‘HONOR AWARD’ from AAPOS in 2016. He has authored publications in various peer-reviewed journals and is a reviewer for Ophthalmology, British Journal of Ophthalmology, AJO, Eye, IJO, EJO, Strabismus and JAAPOS. He is also a ‘section editor’ for BJO.
He is actively involved in teaching and research activities in the pediatric ophthalmology services. His clinical interests include strabismus, pediatric cataract, vision development, lazy eye and neuro-ophthalmological disorders.
Dr. Ramesh Kekunnaya sent us Case 15

Status: CASE CLOSED

Members’ Responses:

1) What is your diagnosis?
38.60% diagnosed the condition as Medial Rectus Avulsion, 12.28% thought it was Medial Rectus Entrapment, 5.26% diagnosed as Flap Tear while 43.86% diagnosed it as Traumatic Slippage of Medial Rectus

2) How would you manage the case?
10.53% of respondents would Observe for now and manage later accordingly, 21.05% would perform Vertical Rectus Transposition, 1.75% would go for Recession and Resection while 66.67% would opt to Manage the case in some other way.

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Experts Opinion

1. WHAT IS YOUR DIAGNOSIS? A. Medial Rectus avulsion B. Medial Rectus Entrapment C. Flap tear D. Traumatic Slippage of Medial rectus

2. HOW WOULD YOU MANAGE THE CASE? A. Observe for now and manage later accordingly B. Vertical rectus transposition C. Recession and Resection D. Manage the case in some other way

Dr. Irene Ludwig

Dr. Irene Ludwig grew up in New York City, where her parents settled after immigrating from Germany.
Her father fled to Switzerland in 1933, and then to the US in 1938, to escape Nazi reprisals for his active
involvement with the Social Democratic party. Her mother’s family fled from Berlin to Prague in 1938,
but were trapped there and endured the war until 1946, when they emigrated to the US.
Dr. Ludwig had the benefit of a wonderful public-school education at PS 163 in Queens, Hunter College
High School in Manhattan, and Queens College in Queens. She was lucky to be admitted to Cornell
Medical College via a special early-decision admissions program in 1975. She pursued an internship in
general surgery at the University of Virginia, 1979-1980, following which she underwent an
ophthalmology residency at the Cleveland Clinic Foundation 1980-1983, a research fellowship at the
National Eye Institute 1983-1985, and a pediatric ophthalmology fellowship at the Children’s Hospital
National Medical Center with Marshall M Parks 1985-1986. She worked for 5 years at the Mary Imogene
Bassett Hospital in Cooperstown NY 1986-1991 (academic), and then for 8 years at the LSU Eye Center in
New Orleans. Dr. Ludwig then left academia to move to Franklin, TN, where she began private practice
with several groups. She still works for two groups and serves patients in Nashville, TN, Huntsville,
Birmingham, and Dothan, AL, and Panama City and Destin, FL.
Dr. Ludwig’s early research focus collaborated with Dr. Parks to analyze his patient data on
accommodative esotropia. At LSU she conducted research in wound healing which lead to her coining
the phrase “stretched scar”, and to her AOS thesis “Scar Remodeling After Strabismus Surgery”. She
also began to observe and repair partial avulsions of rectus muscles of the eyes and began her work on
“flap tear”, another phrase she coined. Her new focus is to develop new strabismus surgical techniques
to correct muscle displacements and pulley disruptions. She maintains research involvement on her
own, and recently completed a textbook with the help of 23 remarkable contributors. It is soon to be
published by Thieme, and will be titled “Strabismus Surgery, Traditions and Innovations”. There are
many videos included with the book.

1) What is your diagnoses?
Medial rectus avulsion. This looks like a complete avulsion of the medial rectus muscle. Flap tears are partial avulsions, and usually have much smaller motility defects. The flap tear patient may sometimes notice diplopia immediately following trauma, but the most common presentation of diplopia is usually 1-2 weeks following trauma, when the flap begins to scar into an abnormal position, creating a tether-type restriction of motility. Complete avulsions are rarer, but can occur. I have seen bilateral trauma in a motorcycle accident, with complete avulsion of the inferior rectus of one eye, and partial avulsion of the IR in the fellow eye, and partial MR avulsions of both eyes. Any combination is possible.

2) How would you manage the case?
Manage the case in some other way. I would explore the muscle without delay and repair the defect.

3) What is your experience with orbital imaging in these kind of patients?
I have had mixed results with imaging in these patients. I do obtain imaging whenever possible, but in young children or uninsured adults, it is best to just explore the muscle surgically. In the case presented here the imaging shows the detached medial rectus muscle, but in other cases it may not be so clear. Imaging would not deter me from direct surgical inspection to find the defect. Some very small flap tears may not show up with imaging, but may have a profound effect on alignment. My main goal with imaging is to identify orbital fractures and associated pulley displacements.

4) What are your surgical tips for managing cases like this?
The main surgical tip is to not dissect away the intermuscular septum and other connections which can lead you to the muscle. These are the landmarks which direct the repair. Indiscriminate dissection in this case could have converted this case to a completely lost MR, instead of the lovely result which was achieved. I use a small fornix incision and dissect nothing until I have identified the detached flap or muscle. I try to incise nothing else. After the muscle is repaired, I repair all the layers, including muscle capsule and the posterior defect in Tenon’s capsule, to reposition any protruding orbital fat. I use non-absorbable 6-0 braided polyester suture (Mersilene or Surgidac) for the muscle repair itself, and 7-0 polypropylene (Prolene) for the capsular repair.

Dr. Fernanda Teixeira Krieger

1) What is your diagnoses?
Traumatic slippage of medial rectus. Photographs reveal a widening of the left palpebral fissure in attempted adduction suggesting disinserted or slipped left medial rectus. This finding is not consistent with medial rectus entrapment or flap tear. In addition, there is no enophtalmos in front and from below views. CT scan shows neither orbital fracture nor muscular entrapment, and left medial rectus muscle is inserted in the eyeball. Furthermore, there is a posterior muscle belly widening of the left medial rectus suggesting slippage. An interesting finding in these images is the presence, on coronal view, of left orbital emphysema with no signs of fracture. It could be due to a superficial orbital laceration or to a trapdoor fracture without muscular entrapment that spontaneously resolved.

2) How would you manage the case?
Observe for now and manage later accordingly. Prior to motility evaluation, it is critical to verify that there is no damage to the globe through a careful and complete eye examination, as it was carried out in the current case. Regarding motility evaluation is important to determine whether there is an anomalous head position in binocular and monocular conditions. An AHP when fixing with the affected eye suggests a serious muscular injury or paralysis. This AHP can be made worse by pain-limiting eye movement. Pain, muscle injury, edema and hemorrhage could also make difficult to evaluate ocular alignment by alternate prism cover test. Therefore, measurements are often performed using Krimsky light reflex testing, at primary position at distance and near, in secondary gaze positions, fixing each eye. Having conditions, alternate cover test with prism is performed. Versions and ductions completed the initial motility evaluation in a case like this. In orbital trauma, the presence of mechanical limitations and palsy or paralysis should be addressed by further examination, such as saccadic velocity, forced duction testing and force generation testing. In the current case, and when there is suspected muscle trauma, I will not carry on these studies. Traction in the involved muscle may disrupts the remaining attachments that prevent the muscle to be lost or retract more posteriorly. If necessary, FDT may be performed gently to detect restriction. In addition, pain-limiting eye movements, along with edema and hemorrhage, could interfere with the interpretation of these studies. Concerning imaging in orbital trauma, I will combine the issues also raised in the next question. In orbital trauma, first I consider CT scan. It helps in identifying orbital fracture, its location and extent, and muscle entrapment. Although its disadvantageous in soft tissue, it provides information regarding muscle insertion at the globe and muscle transection. In the current case, the widening of the left medial muscle belly suggested the presence of slippage. A further MRI in this case would show better the conditions of the muscle attachment to the globe, such as the location and the presence of an empty capsule connecting to the globe. In cases of flap tears, high resolution MRI and an experienced radiologist would be able to identify an abrupt difference in muscle thickness even near the insertion. After a complete evaluation, with proper diagnosis, mechanism involved, extent and location of the injury, as well as having alternate plans, a surgical exploration and repair should be performed promptly.

3) What is your experience with orbital imaging in these kind of patients?
My comments on this are in previous question.

4) What are your surgical tips for managing cases like this?
Traumatic slippage presents better prognosis than surgical one since intermuscular membranes are not completely sectioned, and the muscle will not be more than 10 -12 mm from its original insertion.
Procedure under general anesthesia. Have an experienced assistant. Request to the anesthesiologist not to atropinize the patient until the muscle is located. Oculocardiac reflex is useful in identifying the muscle. Determine position under general anesthesia. Compare to the position after muscle retrieve and at the end of the procedure. Gently forced duction testing if necessary at this time. Limbal approach to optimize view and decrease damage to surrounding tissues. If there is any difficult in identifying the muscle, consider operating microscope. Make radial incision extending backward above and behind the original insertion, away from the presumed slipped muscle. Create an opening trough Tennon capsule to expose bare sclera. Insert a hook through Tenon’s capsule and grab any residual tissue at the original insertion. In case of an empty capsule or pseudo tendon, this structure is loose, and when it is pulled forward, it will be dislocated easily. A hook or forceps or scissors under this structure will be clearly visible. Use palpebral retractors to a proper exposure. Continue the dissection posteriorly until the muscle is identified. Avoid entering orbital fat. The muscle has a characteristic aspect (meat appearance). Place a suture in the muscle, with generous full thickness bite, before proceeding to the complete dissection of the muscle from the surrounding tissue. Unlike recurrent surgical slippage, in traumatic cases I use absorbable suture (6-0 polyglactin). After cleaning the muscle, completing suture through all the width. Do not use muscle clamp since it can cause additional muscle damage or slippery. Carefully cut the muscle just anterior to the suture. Excise the empty capsule. Suture the muscle back to the original insertion. Do not place the suture anterior to original insertion. Do not use hang-back technique. A temporary bow tie is used to adjust peroperatively and to check abduction. Usually there is no need of additional surgery on other muscle. However, if there was a delay in repairing the damaged muscle, contracture of the antagonist could be present and should be addressed.

Dr. Cristian M. Salgado

Dr. Cristián M. Salgado is a surgeon who graduated from the University of Chile & later specialized in
Ophthalmology at the Pontificia U. Católica de Chile. He was a Fellow in Pediatric Ophthalmology and
Strabismus at the Los Andes Oftalmological Foundation in Chile and, after taking the USMLE exam, did
another fellowship in Pediatric Ophthalmology and Adult Strabismus at the Children´s Hospital Boston of
Harvard University led by Dr. David Hunter, then a third in Neuro-ophthalmology at Johns Hopkins
University under the supervision of Drs. Neil Miller and Prem Subramaniam. In addition, he studied
biostatistical methods in scientific research at the Pontificia Universidad Católica de Chile, obtained the
degree of Diploma in Teaching in Medicine and completed a Master’s Degree in Health Administration
at the same University. He has authored numerous international and national publications as well as
author of book chapters in the area of pediatrics and neonatologyin Chile.
He is currently Head of the Ophthalmology Department of the Pontificia U. Católica de Chile. He is an
international member of AAPOS (American Academy of Pediatric Ophthalmology and Strabismus) and
NANOS (North American Neuro-Ophthalmology Society).

1) What is your diagnosis?
This looks like a traumatic slippage of the medial rectus, even though the term “slipped” usually is referred after strabismus surgery, I think this case has clinical aspects that oriented to that diagnosis.
There is an obvious history of trauma, although the exact mechanism is not mentioned. (We can infer indirectly that the intensity of the trauma was not of high energy since gonioscopy is normal)
The acute horizontal diplopia along with total adduction deficit give some clues related to “no active muscular function“ the large XT en ppm and >90 XT on right gaze is very common in “lost or slipped muscles “. A tear flap and /or avulsion of medial rectus can have sometimes this amount of traumatic squint deviations but usually, in my experience you can find some adduction force or restriction in contralateral gaze (this patient fuse in extreme left gaze) and also give more “traumatic appearance of the globe“ if it is of acute origin. I mean , red , bloody eyes with more damaged over tissues of the ocular/ bone surface. It´s very interesting to me the “white” aspect of the eye, with a clean conjunctival tear and hypertrophic tenons with make my first approach diagnosis ever stronger.
The CT scan actually helps in this case to see that in fact the MR is there and the muscles is not lost to a great extent, suggesting that the muscles has only slipped & isn’t lost into the orbit.

2) How would you manage the case?
In this particular case with only 3 days of diplopia, total deficit of adduction and absence of orbital fracture or other orbital inflammatory damage I will choose option D.
I think observe is not an option, the patient cannot function normally with that huge XT and double vision and also there is no great tissue inflammation around, also, before thinking in vertical transposition I would explore as soon as possible the traumatized zone looking for the muscle, being very careful to put in sutures any tissue that look like muscle, cleaning and dissecting tissues around to identify the MR that I guess will be localized further back. Once the entire MR is sutured I will advance it to its original insertion. Perform a spring back test to be sure that the muscle will be reinserted in the right place. Close the conjunctival flap and see how it goes.

3) What is your experience with orbital imaging in this kind of patients?
In my opinion, a CT scan is the test of choice in this kind of patients, I won’t ask for MRI as a first line imaging because I want to know how the bones are to rule out orbital fractures with or without muscle entrapment. Usually a good CT scan allows to visualize extraocular muscles, orbital hematomas or sometimes lost muscles. I think before going to explore any muscle a CT scan is mandatory.

4) What are your surgical tips for managing cases like this?
As I explained before, to be very careful with the exploration and tissues around the traumatized zone, even if there is no obvious perforation of the globe by direct observation or indirectly by orbital imaging, you always have to rule out intraoperatively this potential complication. Having said that, if sclera is ok, hooked gently the tissues and look around for the muscle, hold any tissue that resembles muscle fibres, sometimes the oculo cardiac reflex helps to identify when you pull the “tissue that look like muscle“ if really it is. The dissection has to be done slowly. Once the proximal end of the muscle is identified and sutured be very careful not to pull hard, be sure the muscle doesn’t have any other tears posteriorly. Finally secured the muscle to sclera at the original insertion with sutures. If I have any suspicion of slippage in the following days after the surgery or the muscle is quite damaged I sometimes add more small sutures laterally 1-2 mm posterior to the insertion to fix even more the muscle to sclera.