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Takaki Miwa

Publications and source records attributed to Takaki Miwa.

15 recordsLinked to original sources
PubMed2006

Posttraumatic olfactory loss.

Head injury is the leading cause of posttraumatic anosmia. Complete or partial loss of olfactory function may occur when the nasal passages are blocked, olfactory nerves are injured or there are contusions or hemorrhages in olfactory centers of the brain. Evaluation of patients with posttraumatic olfactory loss should include a physical examination by the otolaryngologist. Nasal endoscopy and radiological studies should be performed as well as olfactory function tests to determine the degree and type of olfactory impairment. Although treatment options may be limited, physicians should provide information and counseling regarding the risks and hazards associated with loss of olfactory function. For some individuals such as cooks, firefighters, and research scientists, an assessment of vocational activities should be performed prior to reentry into the workplace. Individuals with impaired olfactory function may be unable to detect important warning signs such as gas leaks, volatile chemical fumes and fires and therefore place themselves and coworkers at an increased risk for serious injury or death.

Craniocerebral Trauma↗
PubMed2005

Comparison of diagnostic findings using different olfactory test methods.

OBJECTIVE: To quantify discrepancies in the diagnosis of olfactory function that might exist when comparing results obtained from centers using different methods of olfactory testing. STUDY DESIGN: Prospective study of 50 healthy adult volunteers and 25 adult patients with olfactory complaints. METHODS: Two test methods, the Connecticut Chemosensory Clinical Research Center (CCCRC) test widely used in the United States, and the Jet Stream Olfactometer (JSO) test used in Japan, were used to measure and categorize the diagnostic level of olfactory function (normosmia, mild hyposmia, moderate hyposmia, severe hyposmia, anosmia). Olfactory function was measured separately for each nostril. RESULTS: There was a significant correlation (rs = 0.788, P < .01, n = 150 nostrils) between diagnostic categories assigned by the CCCRC and JSO test methods. Diagnostic categories were identical for 66.7% of the nostrils tested, and in only 7.3% of the cases did the results differ by more than one category. For the anosmic and normosmic categories, test results were in agreement 91.7% of the time, whereas for the hyposmic categories (mild, moderate, and severe) results were in agreement only 22.2% of the time. CONCLUSIONS: Our results demonstrate that when comparing clinical or research data obtained from centers using different olfactory test methods, subjects with diagnoses of anosmia or normosmia may be more reliably compared than those with different levels of hyposmia.

Adolescent↗
PubMed2004

Potential oscillation elicited by i.v. olfaction and its applicability as an objective clinical olfaction test.

OBJECTIVE: Alinamin has long been applied in Japan for testing i.v. olfaction and to diagnose olfactory disorders. The test is subjective, each subject being asked about the presence or absence of olfaction. The credibility of the answers is highly questionable in some cases; as a result, the reliability of the test is poor. Recent studies demonstrated an induced electric potential in the scalp during i.v. olfactory testing. Some patients complain of the pain of the injection during i.v. olfactory testing; therefore, the effect of this pain must be considered with respect to measurement of the i.v. olfaction-elicited potential (IVOP). MATERIAL AND METHODS: This investigation involved 179 subjects with various olfaction levels. Each subject received an Alinamin injection; the elicited potential amplitude was compared before and after the injection and the increasing ratio (IR) was computed. Gender, age, level of olfactory disorder, the presence or absence of olfaction and the presence or absence of the pain of injection were considered as factors affecting IR. RESULTS: IR showed significant increases in groups characterized by the presence of olfaction as well as in groups reporting pain of injection. The test subjects were further divided into four groups based on their olfaction and pain of injection patterns as follows: Group A, no smell and no pain; Group B, smell and no pain; Group C, no smell and pain; and Group D, smell and pain. Subjects exhibiting no recognizable olfaction or pain of injection (Group A) revealed no increase in IVOP following injection. Subjects with either recognizable olfaction or pain of injection (Groups B and C) exhibited a slight increase in IVOP following injection. Subjects with both noticeable olfaction and pain of injection (Group D) demonstrated a significant increase in IVOP following the injection with a very high value of IR (>2). Furthermore, there were significant differences between the four groups in terms of IR level, with the exception of Groups B and C. CONCLUSIONS: Olfaction is largely involved with the generation of IVOP. However, pain resulting from injection of Alinamin is considered to be a significant factor. IVOP showed significant effectiveness for diagnosing olfactory disorders in cases who did not experience pain of injection.

Adolescent↗
PubMed2004

Olfactory impairment and Parkinson's disease-like symptoms observed in the common marmoset following administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.

OBJECTIVE: Although olfactory disturbance appears to occur in the early stages of Parkinson's disease (PD) in humans, little is known about its mechanism. The aim of this study was to make a PD model using injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the common marmoset and to discover the mechanism of olfactory disturbance in this animal. MATERIAL AND METHODS: Olfactory disturbance induced by MPTP in the common marmoset was observed by behavioral, biochemical and immunohistochemical means. RESULTS: Administration of MPTP caused common marmosets to enter an akinetic state within a few days and to show signs of impaired olfactory function. Biochemical study showed a decrease in dopamine levels, especially in tissue samples from the caudate nucleus and putamen. Immunohistochemical analysis revealed a lack of tyrosine hydroxylase immunoreactivity, not only in the substantia nigra, caudate nucleus and putamen but also in the olfactory tubercle. CONCLUSION: These results demonstrate that MPTP causes both PD-like symptoms and olfactory disturbance in the common marmoset. The olfactory disturbance observed in these animals may be due to the lack of dopamine in the olfactory tubercle.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed2004

[Head and neck reconstruction using laparoscopically harvested omentum].

Since the need for laparotomy in harvesting the omentum is the most significant drawback, the omentum has not been the tissue of choice for reconstructive surgery. To compensate for this drawback, we started laparoscopic harvesting of the omentum and clarified the advantages and disadvantages of this procedure. Ten patients underwent laparoscopic harvesting of the omentum by abdominal surgeons, followed by reconstruction of head and neck defects. Surgery was conducted in 5 cases of defect reconstructions for parotid gland tumor surgery and 5 of oropharyngeal defect after cancer surgery. The average harvesting time was 107 minutes (55-140 minutes) and used the omentum and different amounts and length of the vascular pedicle. Although the omentum was successfully transplanted in 9 of 10 cases, 2 cases showed partial peripheral necrosis and 1 total necrosis. With the advantage of laparoscopic harvesting of the omentum, we could obtain appropriate omental size for the defect size. Especially after total parotidecomy, the omentum was useful to fill in the defect, reducing the patients' worries about postoperative deformity. In one case, the omentum was used to treat Frey syndrome, successfully relieving the symptoms. In oropharyngeal reconstruction, the omentum is used to fill dead space and prevented postoperative infection. Although mild abdominal pain was observed a few days after surgery, no major abdominal complications such as intestinal perforation or ileus occurred in the 8 to 39 months following laparoscopic harvest of the omentum. Since the omentum is pliable and easily fills a complicated defect, the omentum is considered satisfactory for reconstructing defects of the lateral face after parotid tumor surgery and small defects after oropharyngeal tumor surgery.

Aged↗
PubMed2004

[Clinical usefulness of odor stick identification test for patients with olfactory disturbance].

The odor stick identification test for Japanese (OSITJ) is the latest in measuring olfactory identification. It consists of 13 odorants familiar to the Japanese population. We studied the relationship between the Japanese standard olfactory test (T & T olfactometer) and the OSITJ in 182 patients with olfactory disturbance. The identification ratio in 2 of OSITJ tests using 13 odorants was correlated significantly negatively with the detection and recognition threshold measured by the T & T olfactometer. A high correlation between identification ratio and olfactory thresholds was maintained even when the number of odorants in the OSITJ was reduced to 2. For each odorant used, the identification ratio correlated significantly with olfactory thresholds. Results from the OSITJ provide a measure of the degree of olfactory deficit because the ratio of correct answers obtained by the OSITJ decreased gradually with of the severity of olfactory disturbance. Compared to the T & T olfactometer, the OSITJ has several advantages for use in the clinic. These include minimal odor pollution of the test room, simplicity of use, and shorter clinical time needed to administer the test. The OSITJ may be ideal for use in screening due to the minimum number of odorants needed. In conclusion, the OSITJ is useful for detecting and evaluating olfactory disturbance in Japanese people.

Diagnostic Techniques and Procedures↗
PubMed2004

Successful treatment of hemifacial spasm with selective facial nerve block using doxorubicin (adriamycin) under local anesthesia.

OBJECTIVE: To describe our experience with selective chemical rhizotomy of facial nerves using adriamycin (ADM) in a patient with hemifacial spasm (HFS). This unique technique is less invasive than intracranial neurosurgery and enables one to perform a permanent nerve block under local anesthesia. PATIENT: The patient, a 73-year-old female, had difficulty opening her left eye. Following unsuccessful treatment with anti-epileptic medicine, she received selective intraneural injections of ADM under local anesthesia. One week after the surgery the spasms had disappeared completely. No major complications were caused by this procedure and there had been no recurrence of spasms 3 years after the surgery. RESULTS: It is thought that recurrence of HFS should be observed after simple neurotomy due to regrowth of nerve fibers. However, this did not occur after chemical rhizotomy with ADM. This method clearly differs from previously used varieties of simple neurotomy because the latter technique does not cause severe destructive changes in the facial motor nucleus. CONCLUSION: Selective facial nerve chemical rhizotomy with ADM under local anesthesia may be effective in treating a subgroup of patients with HFS, especially elderly patients and those in the high-risk group for general anesthesia and intracranial neurosurgery.

Aged↗
PubMed2003

Detection thresholds for phenyl ethyl alcohol using serial dilutions in different solvents.

Detection thresholds are typically obtained by presenting a subject with serial dilutions of an odorant. Many factors, including the solvent used to dilute the odorant, can influence the measurement of detection thresholds. Differences have been reported in detection thresholds for phenyl ethyl alcohol (PEA) when different solvents are used. In this study we used gas chromatography (GC) to investigate further the effect of solvent on odor detection thresholds. We used a single ascending method and serial dilutions of PEA in four different solvents--liquid paraffin (LP), mineral oil (MO), propylene glycol (PG) and dipropylene glycol (DPG)--to determine the PEA thresholds for 31 adult subjects. For each solvent, we prepared eight serial log base 10 step dilutions (1-8), with corresponding liquid PEA concentrations of 6.3 x 10(1)-6.3 x 10(-6) (% v/v). We found that the threshold concentrations for PEA in LP (step 6.5) and PEA in MO (step 5.5) were significantly lower (P < 0.05) than for PEA in PG (step 4.0) and DPG (step 4.0) We then used GC to measure both the liquid and gas PEA concentrations for the dilution steps prepared with LP and PG. Although there were large threshold differences in the liquid concentrations of PEA in LP and PG, the headspace gas concentrations of PEA were the same. These results demonstrate the importance of determining the gas concentration of odorant stimuli when performing odor threshold measurements, in particular when comparing odor detection thresholds obtained using different solvents.

Adult↗
PubMed2002

Role of nerve growth factor in the olfactory system.

Olfactory neurons are unique in the mammalian nervous system because of their capacity to regenerate in adult animals. It has been shown that olfactory receptor cells located in the olfactory epithelium are replaced on a continuous basis and in response to injury throughout the life span of most species. NGF, which is one of the neurotrophic factors, is present in many areas of the central and peripheral nervous system. It has been shown that NGF in the olfactory bulb plays a role in the survival of cholinergic neurons in the horizontal limb of the diagonal band (HDB). Recent studies of NGF in the olfactory bulb suggest that it is involved in the development, maintenance, and regeneration of olfactory receptor cells. In this study, we review reports examining the relationship between NGF in the olfactory bulb and neuronal regeneration and development in the mammalian olfactory systems. Low- and high-affinity NGF receptor immunoreactivity is markedly expressed during regeneration and at different stages of development in the mouse olfactory system. This level of immunoreactivity is no longer present after completion of regeneration and at maturation. Other findings indicate that NGF injected into the olfactory bulb is transported retrogradely to the olfactory epithelium. It has also been shown that continuous anti-NGF antibody injection into the olfactory bulb causes degeneration and olfactory dysfunction. Administration of NGF directory into nasal cavity results in an increase in the expression of olfactory marker protein within the olfactory epithelium in axotomized rats. These findings suggested that the presence of NGF in the olfactory bulb plays an essential role in regeneration, maintenance, and development in the olfactory system of mammals.

Animals↗
PubMed2002

Glucocorticoid enhances Na(+)/K(+) ATPase mRNA expression in rat olfactory mucosa during regeneration: a possible mechanism for recovery from olfactory disturbance.

Systemic or topical application of glucocorticoid is the treatment of choice for olfactory disturbance. Recently, Na(+)/K(+) ATPase and glucocorticoid receptor immunoreactivity in the olfactory mucosa was reported. To elucidate a glucocorticoid action on Na(+)/K(+) ATPase production, an animal model was produced by an intra-nasal application of 5% ZnSO(4) solution to Wistar rats. Dexamethasone was injected i.p. (0.01 mg/100 g) for 14 days after the insult. Histologically, the regeneration process was completed on day 14 in both dexamethasone- and saline-injected control rats. We used a quantitative polymerase chain reaction (PCR) method to evaluate mRNA production of Na(+)/K(+) ATPase and glucocorticoid receptor. In dexamethasone-injected rats, up-regulation of glucocorticoid receptor mRNA (95% more than control rats, P = 0.00068, unpaired t-test) and of Na(+)/K(+) ATPase mRNA expression (76% more than control rats, P = 0.0042) was observed on day 14. The increased Na(+)/K(+) ATPase expression in the regenerated olfactory mucosa is thought to be beneficial for an active uptake of K(+), which is released during excitation, around olfactory neurons and for the transepithelial absorption of Na(+) from olfactory mucus. Dexamethasone may thus contribute to the recovery of function after the morphological regeneration in part, at least, through its receptor by regulation of the ionic concentration in the olfactory mucosal microenvironment.

Animals↗
PubMed2002

Potential changes with gamma-band oscillation at the frontal scalp elicited by intravenous olfactory stimulation in humans.

Intravenous olfaction is a unique stimulation method often used in Japan to diagnose olfactory disturbances. Odorant is injected into a vein and transported by blood flow and respiration to the upper air tract. The intravenous olfaction might allow the potential at the frontal scalp to be recorded without contamination from electromyograms, such as those caused by sniffing. We injected Alinamin (thiamine propyldisulphide) into healthy subjects according to a standard protocol for clinical intravenous olfaction testing and we simultaneously recorded potential changes at the frontal scalp. When Alinamin was injected into the right median cubital vein over a 20 s period, the potential changes with gamma-band oscillations were detected 17.6 +/- 6.7 s (mean +/- SD) after the start of the injection. The main frequency component of this gamma-band oscillation is 30-160 Hz. The gamma-band oscillation elicited by intravenous olfactory stimulation (VOP) was similar to the induced wave of the olfactory bulb. Mapping the VOPs on the frontal scalp of a subject with less developed frontal sinuses and the relation between the thickness of the frontal sinuses and VOP amplitude suggest an intracranial source, possibly the olfactory bulb. The gamma-band potential at the frontal scalp is a useful measure of central disturbance.

Adult↗
PubMed2002

Nasopharyngeal penicillin-resistant Streptococcus pneumoniae strains among young children in Japan.

OBJECTIVE: A rapid increase of penicillin resistance in Streptococcus pneumoniae has recently been reported in most areas of the world. Penicillin-resistant S. pneumoniae and other resistant bacteria are the principal causes of recurrent acute otitis media (AOM). Penicillin-resistant S. pneumoniae was examined so that we could investigate the bacteriologic and clinical interpretations of nasopharyngeal flora from healthy children. METHODS: We obtained nasopharyngeal swab specimens from healthy children attending a day care center and from children attending a public health examination in Kanazawa, Japan. We also obtained clinical specimens from children with AOM who visited the Kanazawa University Hospital and 4 other hospitals in Ishikawa Prefecture in Japan. RESULTS: The chief bacteria from the children were S. pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Penicillin-resistant S. pneumoniae was identified in 75% of children attending a day care center. On the other hand, S. pneumoniae was identified in 37% of children who were not attending day care. Of the children with AOM, penicillin-resistant S. pneumoniae was identified in 77%. CONCLUSION: Our results suggest that there is a strong relationship between day care attendance and nasopharyngeal carriage of S. pneumoniae. The carriage rate of penicillin-resistant S. pneumoniae in healthy children in day care centers was very high and similar to the carriage rate of young patients with AOM in Japan.

Acute Disease↗
PubMed2002

Electrically stimulated olfactory evoked potential in olfactory disturbance.

Olfactory evoked potential is considered a useful method of electrophysiological olfactometry for the diagnosis of olfactory disturbance. However, electrophysiological olfactometry is not as widely used as electrophysiological audiometry, such as the auditory brain stem response, because odor stimulation is difficult to perform. In contrast, electrical pulse stimulation is easy to perform, and its evoked potential is also easily recorded by the averaging method. We recorded olfactory evoked potentials from the scalp produced by electrical stimulation on the olfactory mucosa and investigated the relationship between this electrical olfactory evoked potential (EOEP) and the results of Toyoda and Takagi's perfumist's strip method (T&T) olfactometry, which is a standard Japanese means of psychophysical olfactometry. In EOEP-detectable cases, the detection and cognitive thresholds of T&T olfactometry were 1.32+/-1.99 (mean +/- SD; n = 10) and 3.02+/-1.64 (n = 10), respectively. But in the undetectable cases, the thresholds were 4.67+/-2.03 (n = 8; 5.8 means off the scale) and 5.80+/-0.00 (n = 8), respectively. The differences between the T&T thresholds of EOEP-detectable and -undetectable cases were significant. We concluded that EOEP is suitable for electrophysiological olfactometry.

Electric Stimulation↗
PubMed2002

Osteocartilaginous differentiation of mucosal melanoma in the sinonasal cavity.

We present a very rare case of mucosal melanoma with osteocartilaginous differentiation (MMOD). This is the first report of MMOD originating in the sinonasal cavity. Preoperative diagnosis of this tumor from specimens resected for biopsy alone is very difficult, because it has 2 histopathologic components: a primary melanoma site and the part of the melanoma with osteocartilaginous differentiation. The immunohistochemical technique is useful in histopathologic diagnosis of this tumor. Malignant melanoma usually shows reactivity with MelanA (melanoma tumor antigen) and S-100 proteins. We diagnosed this case as MMOD because both regions in this tumor were stained with MelanA and S-100 proteins. Magnetic resonance imaging provides the best clinical ability to detect malignant melanoma in the sinonasal region. In this case, the melanotic melanoma site in the posterior ethmoid sinus appeared hyperintense to gray matter on T1-weighted image magnetic resonance imaging. Thus, it would have been possible to diagnose this case as MMOD before operation, even though we could not obtain a biopsy specimen from the posterior ethmoid sinus lesion.

Aged↗