Proceedings of a Workshop on - The Havemeyer Foundation

Havemeyer Foundation Monograph Series No. 11
surgery, 6% were able to perform reduced work,
and one horse was retired. Fify-nine percent <strong>of</strong>
owners reported that the horse’s performance had
increased as compared to pre-operative
performance, 16% reported no change, and the
remaining owners were unsure <strong>of</strong> any such change
(Fig 3). Overall, 86% <strong>of</strong> owners considered the
surgery to be worthwhile, 3% did not consider it to
be worthwhile, and 11% were unsure <strong>of</strong> its value
(Fig 4).
DISCUSSION AND CONCLUSIONS
When compared to LP procedures, VC had a
lower rate <strong>of</strong> post operative complications.
Unsurprisingly, healing <strong>of</strong> the laryngotomy wound
was very similar to healing in horses that
underwent LP with VC (Dixon et al. 2003a), with
the vast majority <strong>of</strong> horses having no discharge
from the surgical site at 2 weeks post operatively.
However, in horses which underwent LP plus VC,
an additional 19% had wound complications
(seromas, suture abcesses etc) associated with the
LP wound. Although 22% <strong>of</strong> horses coughed post
VC, this is considerably fewer than the 43% <strong>of</strong>
horses which coughed after LP, and this is
unsurprising because after VC the arytenoid
cartilages are not fixed in an abducted position and
should be able to adduct and protect the airway
during deglutition. Additionally, in the majority <strong>of</strong>
horses which did cough post VC, coughing was
not associated with eating and may therefore be
attributable in some cases to pre-existing lower
airway disease (present in 29% <strong>of</strong> horses) rather
than dysphagia due to surgical interference.
A larger percentage <strong>of</strong> horses were reported to
make abnormal respiratory noises post VC (34%)
as compared to LP combined with VC (27%)
(Dixon et al. 2003a) even though the group which
underwent VC alone had a lower pre-operative
median grade <strong>of</strong> RLN than those undergoing VC
combined with LP. This is surprising given that the
majority <strong>of</strong> noise is thought to arise from vibration
<strong>of</strong> the vocal cord in horses afflicted with RLN
(Hammer et al. 1998; Kidd and Slone 2002).
Similarly, slightly fewer horses were considered
subjectively to have increased exercise
performance post operatively as compared to
horses which underwent LP, but the overall rate <strong>of</strong>
owner satisfaction was very similar for the 2
procedures.
This study shows that ventriculo-cordectomy
is a useful alternative to laryngoplasty for selected
cases <strong>of</strong> RLN and is associated with a low post
operative complication rate and a high rate <strong>of</strong>
owner satisfaction.
REFERENCES
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Dixon, P.M., McGorum, B.C., Railton, D.I., Hawe, C.,
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Lane, J.G. (2003) Differences between resting and
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