Chem. Senses 27: 117-121,
2002
© Oxford University Press 2002
Olfactory Acuity after Total Laryngectomy
Department of Otorhinolaryngology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan 1 Takarazuka Municipal Hospital, Hyogo, Japan
Correspondence to be sent to: Megumi Fujii, Department of Otorhinolaryngology, Hyogo College of Medicine, Mukogawa-cho, Nishinomiya, Hyogo 663-8501, Japan. e-mail: megumi{at}hyo-med.ac.jp
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Abstract |
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The olfactory acuity of 29 patients receiving laryngectomy was prospectively studied. The olfactory acuity was evaluated by Jet Stream Olfactometer (JSO) and Alinamin® test preoperatively and at 3, 6 and 12 months postoperatively. The findings of nasal/olfactory mucosae were also observed by rigid endoscope. Based on the results of JSO, the averages of detection/recognition thresholds tended to increase 3 months postoperatively, then the averaged thresholds tended to decrease thereafter. There were significant differences between preoperative values and those 3 months after surgery, but there were no significant differences between preoperative values and these 6/12 months after surgery. Nasal respiratory mucosae observed 12 months after laryngectomy showed atrophic nasal mucosa in 11/14 patients. However, olfactory mucosae appeared normal in all of the patients observed. These results suggested that the function of the olfactory epithelium remained intact after laryngectomy.
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Introduction |
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TopAbstractIntroductionExperimentalResultsDiscussionReferences |
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Laryngectomees often present severe hyposmia or anosmia (Ritter, 1964
;
Henkin et al., 1968;
Henkin and Larson, 1972). After
total laryngectomy, olfactory acuity decreases due to the loss of nasal
airflow and the necessity to breathe through the tracheo-stoma
(Mozell et al., 1983;
Moore-Gillon, 1985).
Laryngectomy also causes the nasal mucosae to become atrophic
(Ritter, 1964;
Henkin and Larson, 1972). Hoye
et al. stated that the factors inducing atrophy of the olfactory
neuroepithelium and/or bulb may play a role in the olfactory problems of
patients after laryngectomy (Hoye et
al., 1970). However, it has not been demonstrated whether the
olfactory epithelia of laryngectomees become atrophic, because it is difficult
to measure olfactory function in the absence of nasal airflow.
Recently, a new olfactory test, the Jet Stream Olfactometer (JSO), was
developed as a modification of the T&T olfactory test that is now
performed routinely in Japan (Japan
Rhinology Society, 1998). JSO has the advantage that odorants are
sprayed on the olfactory epithelium and patients do not need to breathe.
Therefore, we used JSO to measure olfactory function in post-laryngectomy
patients who can no longer breathe through the nasal cavity.
The Alinamin® test is a standard olfaction test in which Alinamin®
is intravenously injected, and the latency and duration of recognition of a
garlic-like odor (Alinamin®) is measured. It is believed that injected
Alinamin® reaches the lung and diffuses to the pulmonary alveoli, then
stimulates the olfactory epithelium via the nasopharynx
(Zusho, 1983). However, the
mechanism by which a garlic-like odor (Alinamin®) is recognized is not yet
clear.
This study evaluated the olfaction of laryngectomees prospectively using JSO and Alinamin® test and clarifies the mechanism of stimulation for the olfactory epithelium with Alinamin®.
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Experimental |
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TopAbstractIntroductionExperimentalResultsDiscussionReferences |
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Olfactory acuities of 29 patients who had undergone laryngectomy between July 1997 and December 2000 were prospectively studied. The patients were 26 males and 3 females with a mean patient age of 68.7 years. The cases included 13 cases of hypopharyngeal cancer, 15 cases of laryngeal cancer and one case of thyroid cancer. None of the patients had any diseases of the nose and sinuses (e.g. nasal allergy, sinusitis), and did not present olfactory dysfunctions. The olfactory functions were evaluated four times (preoperatively, and at 3, 6 and 12 months postoperatively) by JSO (Japan Rhinology Society, 1998
)
(JSO, Nagashima Medical Instruments Co., Japan) and Alinamin® test.
JSO (Japan Rhinology Society,
1998) is a new olfactory test based on the T&T olfactometer
(Zusho, 1983). T&T
olfactometer (Takasago Industry, Tokyo, Japan) is a practical olfaction test
kit that includes five odorants (A—E), while JSO includes three (A, B,
C) of the same five odorants. Odorant A is a dilution of ß-phenyl ethyl
alcohol (smells like a rose), odorant B is a dilution of cyclotene (smells
like burning) and odorant C is a dilution of isovaleric acid (smells like
sweat). Concentrations of each odorant range over eight degrees of intensity
(-2-5) except for odorant `B' (-2-4). These odorants can be sprayed into the
nasal cavity and stimulate the olfactory epithelium using the instrument
(Figure 1). The detection
threshold is defined as the lowest concentration detectable by the subject,
whereas the recognition threshold is defined as the lowest concentration at
which the odor can be identified. Subsequently, the detection and recognition
threshold in three odorants were averaged and the olfactory acuity was
evaluated using the averaged values. The patients' olfaction levels were
classified into three groups; threshold decrease by more than one degree is
defined as `improved', threshold increase by more than one degree is defined
as `worsened' and threshold change within ±1 degree is defined as
`stable'.
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The Alinamin® test (Zusho,
1983) is the intravenous olfaction test. Alinamin® (Takeda
Pharmacy, Osaka, Japan) is a thiol-type derivative of vitamin B1, and it
smells like garlic. The test method is as follows: a dose of 10 mg (2 ml)
Alinamin® is injected into the median vein of the left arm at a constant
rate over 20 s, and the latency interval and the duration are measured. The
latency interval is the time until recognition of the smell. Duration is the
time from recognition until disappearance of the smell. In normal cases, the
latency interval is 7-8 s, and the duration is 1-2 min. In laryngectomees, we
instructed them to use nasal plugs during the test to prevent breathing the
garlic smell from the tracheo-stoma.
The conditions of nasal/olfactory mucosa were also examined with a rigid endoscope (Olympus Selfoscope, Tokyo, Japan) when the olfactory functions were tested. In addition, another group of 27 patients (22 males and 5 females with a mean age of 67.0 years) that were 1 year post laryngectomy were surveyed by a questionnaire about the olfactory acuity, and their subjective symptoms were indicated in response to 15 items (Figure 2).
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Results |
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TopAbstractIntroductionExperimentalResultsDiscussionReferences |
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In JSO experiments, in many cases, the mean detection/recognition thresholds tended to increase 3 months postoperatively, then decrease 6 and 12 months postoperatively (Figure 3). There were significant differences in the average detection/recognition thresholds between before surgery and 3 months after surgery (P < 0.05), while there were no significant differences between before surgery and 6 months after or between before surgery and 12 months after surgery (Wilcoxon signed-ranks test). The results of the average recognition thresholds were also changed in the same course.
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Although the patients could not breathe through the nasal cavity, 70-80% of the patients were positive for the Alinamin® test after the laryngectomy. Many positive cases showed latency intervals that were shortened, while the duration was extended after laryngectomy (Table 1). There were significant differences in the latency interval between values obtained before and 3, 6 and 12 months after surgery. There were significant differences in duration only between values obtained before and 6 months after surgery (paired t-test) (Figure 4).
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Although the respiratory mucosae were atrophic to greater or lesser degrees in 12 of 25 patients (48.0%) at 3 months after surgery, in 16 of 22 patients (72.7%) at 6 months after surgery, and in 13 of 14 patients (92.9%) at 12 months after surgery, their olfactory mucosae had normal appearance (yellowish-brown in color, no edema and non-atrophic).
In the questionnaire survey, the average score for all cases was 6.7, and 25/27 cases (92.6%) were conscious of hyposmia. However, there were only two patients who could not smell at all (7.4%), while the other 25 patients (92.6%) reported some ability to smell.
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Discussion |
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TopAbstractIntroductionExperimentalResultsDiscussionReferences |
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Laryngectomees have many problems in their daily life (Furukawa, 1998
). There have
been several studies of olfactory function after laryngectomy
(Ritter, 1964;
Henkin et al., 1968;
Henkin and Larson, 1972), but
it remains unclear whether olfactory function decreases. Therefore, we
prospectively examined the function of olfactory acuity before and after
laryngectomy.
Negishi et al. reported that olfactory acuities of laryngectomees
functioned normally on their original olfactory test when odorants of T&T
olfactometer were sprayed into the nose
(Negishi et al.,
1986). However, the report described a retrospective study that
contained many patients who had undergone laryngectomy considerably earlier;
the mean time after laryngectomy was 4.1 years. DeBeule and Damste noted that
95% of patients presented a noticeable loss of olfaction following
laryngectomy, but half of their series showed at least some degree of
improvement within a year after surgery
(DeBeule and Damste, 1972).
Recently, Welge-Lussen et al. examined 25 laryngectomees using the
Sniffin' Sticks test and chemosensory evoked potentials
(Welge-Lussen et al.,
2000). All cases in their series were anosmic/hyposmic on the
Sniffin' Sticks test, but at least two-thirds of the laryngectomized patients
showed some olfactory function up to 22 years after surgery when chemosensory
evoked potentials were examined.
In the present study, there were significant differences in olfactory acuities before and 3 months after surgery, but there were no significant differences on comparison of values before and 6 months after surgery. Therefore, the olfactory functions of laryngectomees initially worsened, then improved to almost the pre-laryngectomy level. In the questionnaire survey, most of the patients responded that their olfactory acuities had worsened, but 92.6% of them experienced some smells in their daily lives. Many cases presented normal olfactory mucosae although respiratory mucosae were atrophic. These results suggested that the functions of olfactory epithelium remained intact after laryngectomy.
The olfactory functions of laryngectomees became worse 3 months after the
surgery, then the olfactory functions later recovered. The cause of this
change was considered as follows: 13 of 29 patients had hypopharyngeal cancer.
All cases of hypopharyngeal cancer underwent radiation therapy and
chemotherapy postoperatively. The time of 3 months after surgery is consistent
with completion of the therapies. Almost all cases of hypopharyngeal cancer
received one or two series of chemotherapies consisting of carboplatin and
fluorouracil. There are some reports of hyposmia caused by chemotherapy using
tegafur (Majima et al.,
1986), but this hyposmia occurred after long-term oral
administration. It is difficult to consider that chemotherapy induced hyposmia
3 months postoperatively in our series. Concerning radiation therapy, the
noses and paranasal sinuses were excluded from the radiated area in all cases.
Therefore, radiation therapy did not cause dysfunction of olfactory nerves.
Therefore, we considered the other possibility that postoperative radiation
and chemotherapy caused great physical/mental stress and that olfactory
function could therefore be worst 3 months postoperatively.
The present study clearly showed that olfaction persisted in most
laryngectomees. Hilgers et al. reported that olfactory acuity could
be rehabilitated after laryngectomy in 
50% of patients by applying a
nasal airflow-inducing maneuver of yawing with closed lips
(Hilgers et al.,
2000). We considered that laryngectomees could become aware of
smell in similar ways.
Most laryngectomees were positive on the Alinamin® tests. It is
generally understood that Alinamin® injected into the vein diffuses into
the pulmonary alveoli and the odorant of Alinamin® stimulates the
olfactory mucosa through the nasopharynx
(Zusho, 1983). According to
this theory, all laryngectomees should be negative in an Alinamin® test
because the nasal cavity and lower respiratory tract are separated. In the
present study, most laryngectomees were positive on Alinamin® test and
only 20-30% of cases were negative, suggesting that injected Alinamin®
stimulated the olfactory mucosae not only from the pulmonary alveoli via the
nasopharynx but also diffused from blood vessels of the nasal mucosa into the
nasal cavity and/or secreted from Bowman's gland, then directly stimulated the
olfactory cilia.
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References |
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TopAbstractIntroductionExperimentalResultsDiscussionReferences |
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DeBeule, G. and Damste, P.H. (1972) Rehabilitation following laryngectomy: the results of a questionnaire study. Br. J. Disord. Commun., 7,141 -147.[Web of Science][Medline]
Furukawa, M. (1998) The opinions from the alaryngeal clients. The Larynx, Japan,10 , 74-76 [in Japanese].
Henkin, R.I. and Larson, A.L. (1972) On mechanisms of hyposmia following laryngectomy in man.Laryngoscope , 82,836 -843.[Web of Science][Medline]
Henkin, R.I., Hoye, R.C., Ketcham, A.S. and Gould, W.J. (1968) Hyposmia following laryngectomy.Lancet , 2,479 -481.[Web of Science][Medline]
Hilgers, F.J.M., van Dam, F.S.A.M., Keysers, S., Koster, M.N., van As, C.J. and Muller, M.J. (2000) Rehabilitation of olfaction after laryngectomy by means of a nasal airflow-inducing maneuver. Arch. Otolaryngol. Head Neck Surg., 126,726 -732.
Hoye, R.C., Ketcham, A.S. and Henkin, R.I. (1970) Hyposmia following paranasal sinus exenteration or laryngectomy. Am. J. Surg., 120,485 -491.[Web of Science][Medline]
Japan Rhinology Society (The Members of Committee of Investigation of Olfactory Function Tests of Japan Rhinology Society) (1998) Clinical usefulness of a jet stream olfactometry.Jpn J. Rhinol. , 37,86 -91 [in Japanese].
Majima, H., Aoki, H., Sugenoya, H., Shirai, O. and Toyoda, B. (1986) Anosmia or hyposmia after long-term oral administration of tegafur—improved anosmia. Gan To Kagaku Ryoho, 13,2128 -2133 [in Japanese].[Medline]
Moore-Gillon, V. (1985) The nose after laryngectomy. J. Roy. Soc. Med.,78 , 435-439.[Abstract]
Mozell, M.M., Hornung, D.E., Leopold, D.A. and Youngentob, S.L. (1983) Initial mechanisms basic to olfactory perception. Am. J. Otolaryngol.,4 , 238-245.[Web of Science][Medline]
Negishi, M., Kobayashi, H., Okabe, H., Watanabe, N. and Nagai, D. (1986) Olfaction in laryngectomized patients—whether loss of function owing to disuse occurs or not.J. Otolaryngol. Jpn , 89,1679 -1685 [in Japanese].
Ritter, F.N. (1964) Fate of olfaction after laryngectomy. Arch. Otolaryngol.,79 , 169-171.
Welge-Lussen, A., Kobal, G., and Wolfensberger, M. (2000) Assessing olfactory function in laryngectomees using the sniffin' sticks test battery and chemosensory evoked potentials.Laryngoscope , 110,303 -307.[Web of Science][Medline]
Zusho, H. (1983) Olfactometry in Japan. Rhinology, 21,281 -285.[Medline]
Accepted October 17, 2001
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