Lateral Ear Resection

LATERAL EAR RESECTION:
ZEPP AND LACROIX PROCEDURES

The occasional ear infection may be a nuisance but at least it can be expected to resolve in 2 - 4 weeks leaving the patient to resume a normal life. Chronic ear infection, however, can be recurring or on-going. Chronic ear infection can lead to dizzying middle ear infections, unending headaches and pain, as well as permeating foul odor. There comes a point when simply managing the infection with cleaning solutions and oral medications is not enough and surgery must be considered. There are two techniques commonly used to benefit the patient with chronic otitis: the Lateral Ear Resection and the Total Ear Canal Ablation. The Lateral Ear Resection is the more conservative approach meant for ears not yet at their “end-stage” where it is thought that more efficient cleaning and better canal ventilation will help.

HOW THE SURGERY WORKS

ear canal

(copyright VIN)

As you probably know by now, the ear canal of the dog and cat consists of both a vertical portion and a horizontal portion, making a “J” shaped ear canal. This configuration is very different from the human “horizontal only” canal which goes straight into the head. Because of the vertical portion that dogs and cats have, it is thought that infectious debris and wax has a harder time draining and that this is an important factor in why dogs and cats have so many ear infections relative to their human family members.

Wouldn’t it be nice if we could get rid of the vertical ear canal and only contend with a horizontal ear canal? Well, it turns out that we can.

Trixie Brooks normal dog ear

Dylan WSGSR Lateral Ear Resection

In the normal dog, the ear flap and vertical
ear canal form a funnel-shape with the
vertical canal being the neck of the funnel.

(original graphic by marvistavet.com)

This dog has had a La Croix procedure. The dotted lines show where the vertical ear canal used to be; only the horizontal canal remains.
(original graphic by marvistavet.com)

The Lateral Ear Resection cuts the vertical canal in half lengthwise down to where the canal turns horizontal. In the Zepp procedure, one version of the Lateral Ear Resection, skin is removed from the area on the outside of (or lateral to) the ear so that the dissected half of the ear canal can be folded down to form a “drain board.” In the LaCroix procedure, the outer (lateral) part of the vertical canal is simply removed and the new ear opening is formed from the tissue in the area The result either way creates an ear opening that is more like the human ear opening: straight in. The ear can be more easily cleaned and since ventilation is now better, the canal is less suited to incubate bacteria. This procedure is relatively simple and referral to a specialist is generally unnecessary.

normal ear

first set of incisions

flap down

normal ear

The dotted line indicates first
set of incisions, through the
skin and cutting the round
ear canal in half lengthwise

The dissected ear canal is pulled down and the flap is sewn to the skin.
Circle indicates the new opening of the ear canal

(all three illustrations original graphics by marvistavet.com)

AFTERCARE

Post-operative care after Lateral Ear Resection includes the use of an Elizabethan collar to protect the delicate incisions from scratching. This is worn for 10-14 days at which time any external sutures can be removed.

The ear will still require treatment of its infection so topical and oral medication will continue to be used.

THE CAVEATS

Before calling up your veterinarian’s office to schedule this procedure right away there are a few facts to be aware of.

  • The underlying cause of the ear infection is not addressed by this procedure. If the pet has allergies, hormonal issues, or problems beyond ear conformation as the predisposing factors to chronic ear infections, this surgery addresses none of them and infections are still likely to recur. This surgery simply makes cleaning the ear easier.
     
  • If the patient has developed proliferative ear growths down the canal (a common occurrence making ear cleaning particularly difficult) and these growths are present in the horizontal canal as well as the vertical canal, then this surgery will not be successful. To check for narrowing all the way down the canal, a radiograph taken under sedation should indicate how narrow the horizontal canal is. Ideally, more advanced imaging of the ears should be performed (such as MRI or CT) to rule out the presence of middle ear infection as well as inner ear tumors. Either of these situations would indicate need for a more aggressive surgery; however, this kind of imaging is not available to pets in many communities while most veterinary hospitals have capability to perform radiographs.
     
  • One well known study reviewed 60 dogs receiving lateral ear resections. The procedure was considered a failure in 86.5% of Cocker Spaniels in which it was used. In other breeds, 63% were found to have acceptable results. If your dog is a Cocker Spaniel, this is a breed for which the Total Ear Canal Ablation is likely more appropriate.
     
  • If there is any reason to think a middle ear infection is present (see section on Vestibular Disease) a Lateral Ear Resection will not provide adequate control of the situation.
     
  • Some surgery specialists strongly prefer that the Lateral Ear Resection be performed before they perform a Total Ear Canal Ablation (or TECA) in case the more conservative procedure is successful. If you are leaning towards the TECA surgery, check with the surgeon to be sure they are willing to do it without a prior Lateral Ear Resection in your pet’s situation.
     
  • One of the chief complications of the Lateral Ear Resection is stricture at the entrance of the re-shaped ear canal. In other words, the new ear canal entrance may scar into a hole too narrow for proper ear treatment. This complication requires a revision of the ear canal entrance and is generally simple.
     
  • The other classical complication of Lateral Ear Resection is called “dehissence” which means that the stitches do not hold. This happens when there is too much tension on the tissue or too much infection. If this occurs, the tissue is left to heal in naturally which takes longer than healing with stitches. The Elizabethan collar will be needed in this event until healing is complete.
     

Page last updated: 2/23/2014