1.Research Summary
Department of Otolaryngology - Head and Neck Surgery carries out highly-qualified research in the broad field of otolaryngology, head and neck surgeries. We have many collaborating projects with other departments in Niigata University including brain research institute, departments of molecular physiology, neuroanatomy, molecular and cellular pathology, and psychiatry.
2.Research Groups
3-1.Vestibular and Auditory Research
Persistent Postural Perceptual Dizziness (PPPD)
Prof. Horii is acting as a subcommittee member of International Classification
of Vestibular Disorders (ICVD) of Barany Society, the world-wide biggest
society for vestibular science. This subcommittee recently proposed a definition
of chronic functional dizziness named Persistent Postural Perceptual Dizziness
(PPPD). PPPD patients have persistent dizziness or unsteadiness lasting
for more than six months and the symptoms are exacerbated by upright position,
active or passive movement and exposure to moving or complex visual stimuli.
Our group is conducting research on PPPD from the basic level using rat
animal models to the clinical research aiming to develop new diagnosing
modality and treatment of PPPD.
Clarification of pathology of otitis media with antineutrophil cytoplasmic
antibody (ANCA)-associated vasculitis (OMAAV)
The antineutrophil cytoplasmic antibody (ANCA) against neutrophil lysosomal
enzymes such as myeloperoxidase (MPO) and proteinase 3 (PR3) releases lytic
enzymes that cause vascular inflammation; this leads to systemic vasculitis
known as ANCA-associated vasculitis (AAV). These ANCA-associated diseases
may involve organs throughout the body, such as the eye, nose, ear, lung,
and kidney. Recently, the occurrence of otologic symptoms such as otitis
media and hearing loss frequently have been reported in patients with AAV.
These cases are difficult to diagnose at the early stage and OMAAV may
cause some permanent dysfunction such as severe hearing loss. Japan otological
society organized the OMAAV working group for clarification of OMAAV pathology.
Dr. Morita is a member of this working group and contributes to the accumulation
of the OMAAV patients to establish the appropriate treatment and follow-up
methods.
Middle ear cholesteatoma
Middle ear cholesteatoma is a challenging condition due to its progressive
and destructive characteristics. Until recently, there was no staging system
of cholesteatoma that are parallel to treatment outcome. In 2010, the Japan
Otological Society (JOS) proposed JOS staging system for middle ear cholesteatoma
(2010), and it became widely used in Japan. As a member of the Japan Otological
Society Terminology Committee, Dr. Morita has cooperated with constructing
the database of cholesteatoma in nation-wide and writing the draft of staging
system and its revision at 2015. At 2017, European Academy of Otology and
Neurotology (EAONO) also proposed the staging system of cholesteatoma,
which was basically the same staging system by JOS. Based on these databases,
the validity and utility of this staging system is being verified by multicenter
clinical trials. In addition, we are conducting research how to select
the appropriate surgical method for each individual.
3-2.Nasal and Laryngo-Pharyngeal Research
Pathophysiological mechanisms of globus sensation of throat: involvement
of gastro-esophageal reflex and anxiety disorder
The globus sensation is defined that the patient has a persistent sensation
of having a lump in the throat with no detectable physical cause. Recently,
the number of globus patients is increasing, which is around 5-10% of patients
in ENT outpatient clinic. The most plausible theory of globus sensation
is that it is caused by the gastro-esophageal reflex of gastric acids.
However, some cases are refractory to proton pump inhibitor (PPI) treatment.
As other characteristics of the globus sensation patients, they are sometimes
anxious and depressive for whom anti-anxious medicine is partly effective
in relieving the symptoms. Therefore, globus sensation may be multifactorial
disease.
In this project, we translated the current most useful questionnaire to
evaluate the subjective symptoms of the globus sensation, namely Glasgow-Edinburgh
Throat Scale (GETS), into the Japanese for the first time and are now validating
the Japanese version. The second purpose of this project is to construct
a diagnosing algorithm of the globus sensation based on the gastro-esophageal
reflux (GER) testing (upper gastro-intestinal endoscopy, pH monitoring,
esophageal manometry) and psychiatric assessment using the Hospital Anxiety
and Depression Scale (HADS) questionnaire. The ultimate purpose of this
project is to build up the tailor-made treatment system for globus sensation
in combination with the diagnosing test battery.
Olfactory function test as a tool for early detection of Alzheimer’s disease
In Japan, the elderly population aged 65 years or over exceeds 1/4 of the
total population for the first time in 2013, and the prevalence of dementia
is estimated to exceed 10%. Alzheimer's disease (AD) is the most frequent
cause of dementia accounting for 40 to 60% of all dementia. Because of
its irreversible and progressive characteristics, early detection and prompt
start of treatment is important. For this purpose, an early diagnosing
battery for AD is expected.
Brain atrophy of AD begins from the medial temporal lobe (MTL) including
the primary olfactory area, and therefore, olfactory dysfunction is one
of the initial symptoms of AD. In addition, as initial MTL atrophy is unilateral,
there is a possibility that the olfactory dysfunction is also unilateral
at the early stage of AD. In this study, we elucidate the relationship
between the olfactory disorder and the right-left difference of MTL atrophy
in early AD and examine whether olfactometry can be a new biomarker in
early detection of AD.
3-3.Head and Neck Oncological Research
Our group have conducted several multicenter studies in Niigata Prefecture,
which analyzed the safety and tolerance of concomitant chemoradiotherapy
with high dose cisplatin, and utility of swallowing exercise for head and
neck cancer of disability.
We have also performed basic research in cooperation with molecular pathology
department, division of gastroenterology, and pathological department.
Our molecular research is focused on cancer microenvironment (tumor stroma,
hypoxia or cytokines, etc.). We have identified some protein hydroxylases,
which are known to be involved in hypoxic response, as the targets for
novel anti-cancer therapy. We are doing pathological analysis about the
superficial laryngopharyngeal carcinoma with division of gastroenterology
and the pathological department. The superficial laryngopharyngeal carcinoma
is determined that its extension is limited in mucosal or submucosal layer.
Its prognosis is an excellent, but approximately 5% of cases cause cervical
lymph node metastasis. We are analyzing pathological features and endoscopic
findings, which are related to metastasis, to contribute to more precisional
therapy.
