Læknablaðið : fylgirit - 01.06.2005, Page 28

ABSTRACTS / XXIX CONGRESS OF THE NORDIC ASSOCIATION OF OTOLARYNGOLOGY
bone is used for the ossicular chain. Duration of surgery is usually
around 4-5 hours. All procedures are documented in a computer-
based follow-up program 1,3,6 and 9 years after surgery. The sur-
gical technique will be demonstrated using video. Surgical results
from over 450 patients will also be presented (Kinnefors et al.).
Abstract no.: 060
Changes in epidemiology and natural course of otoscle-
rosis
Bretlau P, Dept. of Oto-laryngology, Head&Neck Surgery, Rigshospitalet,
Copenhagen
The incidense of histologic otosclerosis and the course of clinical
otosclerosis seems to change. Based upon human temporal bone
examination the histologic incidense is lower than previously pub-
lished data. Vaccination against measles, fluorisation of the drink-
ing water and delivery later-on in life could be an explanation.
Data from the health authorities of the total number and the
type of operation for otosclerosis in Denmark in the period 1977-
86, 1987-96 and 1997-2003 were calcutated together with data
from our last 241 cases operated for otosclerosis.
The results shows a nearly totally shift from stapedectomies
to stapedotomies (small fenester) from the beginning of the
1980ths as the favorite technique and a reduction of the number
og operations over time from 10.1 per 100.000 inhabitants in
1977 to 5.6 per 100.000 in 2003. In the same period a fewer cases
showed clinical bilateral involved temporal bones. The clinical
manifestation is postponed probably because women prefer
delivery later-on in life.
Conclusion: there seem to be a change in the epidemiology in
otosclerosis with a decline in clinical otosclerosis scheduled for
operation and also in clinical manifestation of the disease.
Abstract no.: 061
Success and complication rates in otoscleros surgery
Karin Ágren M.D.,Ph.D, Dept of Otosurgery, Uppsala University
Hospital, 751 85 Uppsala, Sweden
Stapedotomy (small fenestra technique) has become a routine
technique in otosclerosis surgery in many surgical centres today
mostly due to a reduced risk for sensorineural hearing loss.
Stapedectomy, still used, may offer somewhat better audiological
results in the low frequency area. The aims of the present study
was to compare hearing results, complication rate and subjective
results using a self-evaluation questionnaire one year following
stapedotomy surgery. 140 patients were included with a mean age
of 43 years. Stapedotomy was performed using a 0.6 mm diamond
or a 0.5mm cutting sceeter drill and a Fish 0.4 mm teflon piston-
wire prosthesis was used. Pre- and postoperative air-bone gap,
air-conduction gain and post-operative bone-conduction change
were assessed. Results from questionnaire and audiologic assess-
ments were compared. In 90 % hearing results were reported as
succesfull. In 6 % there was no difference and in 4% hearing was
evaluated as less satisfying. This latter group will be presented and
discussed in more detail.
Abstract no.: 062
Experience with the nitinol smart piston in stapes surgery
Bretlau P, Sprensen MS
Rigshospitalet, Copenhagen
Several different stapesprostheses have been developed and used
since John Shea made the first stapedectomy in 1956. For a succes-
ful hearing result in stapes operations the crimping procedure of
the piston to incus is a crucial one. In trying to minimalize inner ear
trauma during stapedotomies a new piston has been developed.
Closure of the piston around the long proces of the incus is
based upon a non-touch t echnique by heating the piston with
Argon or C02 lasers or by bipolar cautery. The material is nitinol,
a nickel-titaneum alloy and fluoroplastic.
In 44 consequetive cases of stapedotomies this new device has
been used and the results are compared with the classic crimping
technique using a forceps. No difference in closing the air-bone
gab was registred comparing the two techniques and there were
no cases of inner ear hearing loss.
Conclusion: this new prosthesis makes the crimping procedure
during stapedotomies easier and less traumatic to the inner ear.
The advantages and disadvantages using this new prosthesis will
be discussed.
Abstract no.: 063
Preoperative imaging before cochlear implant. Discrepancy
between CT and MRI findings
Mantoni M, Dirksen K-L, Hedegaard-Jensen J. Department of Radiology
and ENT, Gentofte University Hospital, Copenhagen
During the years 1999 to 2004 a total of 183 cochlear implanta-
tions have been performed at the Gentofte University Hospital.
Preoperative imaging before cochlear implantation in our
institution is high resolution CT scanning of the temporal bone, in
the last two years supplemented in selected cases by MRI.
We identified 29 anomalies of the inner ear at CT.
Most common anomalies were Mondini abnormalities and
Mondini variants. MRI with three dimensional FT-CISS image
and MIP surface reconstruction was performed in some of
these patients, and surprisingly sometimes revealed a normal
membranous labyrinth. To our knowledge this phenomenon has
not been reported previously.
Five patients with deafness after meningitis also had the CT
study supplemented by MRI. The CT scan was normal while the
3D-MIP MRI showed subtle fibrous obliteration of the cochlea.
Illustrative cases will be presented and the results will be
discussed,
Abstract no.: 064
Characterization of the fiber structures of the tympanic
membrane
von Unge M, Vasterás Central Hospital, Bagger-Sjöback D, Karolinska
University Hospital, Knutsson J, Vasterás Central Hospital
Background: Retraction of the tympanic membrane is one impor-
28 Læknablaðið/Fylgirit 51 2005/91