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Biomedical subjects

Kuen-Yao Ho

Publications and source records attributed to Kuen-Yao Ho.

At least 19 recordsLinked to original sources
PubMed2006

Analysis of mastoid findings at surgery to treat middle ear cholesteatoma.

OBJECTIVES: To analyze mastoid findings, such as facial nerve dehiscence (FND), labyrinthine fistula, and dural exposure; to review its incidence at cholesteatoma surgery; to analyze its association with semicircular canal fistula; and to elucidate its relationship with dural exposure. DESIGN: One hundred fifty-two patients (65 males and 87 females; 155 ears) were enrolled in a retrospective study of tympanoplasty with or without mastoidectomy. SETTING: Medical university center hospital. RESULTS: The incidence of FND after exenteration of disease was 29.7% (46/155 ears) for total surgical procedures, 29.7% (43/145 ears) for initial procedures, and 30% (3/10 ears) for revision procedures. The prevalence of FND in the tympanic segment only was 87%, with 8.7% in the vertical segment only and 4.3% in both segments. Three patients (2.0%) developed facial palsy postoperatively, with 8 lateral semicircular canal fistulas (5.2% of total ears operated on), half of these with concomitant FND. The incidence of dural exposure of the mastoid tegmen in the entire surgical group was 16.8% (26 ears), 38.5% with concomitant FND. CONCLUSIONS: The overall incidence of FND in our sample was high at 29.7%, with rates of lateral semicircular canal fistula and dural exposure of 5.2% and 16.8%, respectively. The relationship between FND incidence and presence of lateral semicircular canal fistula was positive in our study. The surgeon should bear in mind that the location of FND with cholesteatoma coincides with the most common area of iatrogenic facial nerve injury during otologic surgery.

Adolescent↗
PubMed2006

Huge Thornwaldt's cyst: a case report.

Thornwaldt's bursa, also known as nasopharyngeal bursa, is a recess in the midline of the nasopharynx that is produced by persistent notochord remnants. If its opening becomes obstructed, possibly due to infection or a complication from adenoidectomy, a Thornwaldt's cyst might develop. Here, we present a 53-year-old man who complained of nasal obstruction that had progressed for 1 year. Nasopharyngoscopy showed a huge nasopharyngeal mass. Thornwaldt's cyst was suspected. Magnetic resonance imaging showed a lesion measuring 3.6 x 3.4 cm, intermediate on T1-weighted and high signal intensity on T2-weighted imaging, neither bony destruction nor connection to the brain. The patient underwent endoscopic surgery for this huge mass. Afterwards, his symptoms improved significantly. We present the treatment and differential diagnosis of a nasopharyngeal cyst.

Cysts↗
PubMed2006

The prognostic value of proliferating cell nuclear antigen (PCNA) and p53 protein expression in patients with advanced nasopharyngeal carcinoma.

CONCLUSION: p53 protein and proliferating cell nuclear antigen (PCNA) were not ideal prognostic indicators in advanced nasopharyngeal carcinoma (NPC). Further investigation in searching for other potential biomarkers is needed to enhance the prediction of treatment outcome. OBJECTIVE: To assess the prognostic significance of p53 protein and PCNA expression in patients with advanced NPC. PATIENTS AND METHODS: This study included 46 patients with advanced NPC who had received treatment and regular follow-up for at least 5 years. We used immunohistochemistry (IHC) staining to assess p53 protein expression and PCNA labeling index, and correlate them with pathological subtypes, TNM stage, the presence of locoregional recurrence, and 5-year survival rate. RESULTS: p53 nuclear staining was positive in 32 patients (69.6%). All cases had positive PCNA nuclear staining with labeling index (LI) ranging from 6.5% to 92.9% (mean 53.4%). Only advanced T stage was found to be associated with high PCNA LI. Overexpression of p53 and PCNA LI had no impact on 5-year survival in this study group.

Adult↗
PubMed2005

Different impact from betel quid, alcohol and cigarette: risk factors for pharyngeal and laryngeal cancer.

The risks of betel quid chewing with or without tobacco, alcohol drinking and cigarette smoking have been well explored in the oral cavity but not in the pharynx and larynx. We conducted a case-control study to investigate the association of these three risk factors to cancers of the pharynx and larynx in Taiwan. A total cases of 148 pharyngeal cancer, 128 laryngeal cancer and 255 hospital controls, all men, were recruited. Betel quid chewing was a significant independent risk factor (adjusted odds ratio [aOR] = 7.7; 95% confidence interval [CI] = 4.1-15.0) similar to that of alcohol drinking (aOR = 6.6; 95% CI = 3.5-13.0) for pharyngeal cancer, but not for laryngeal cancer (aOR = 1.3; 95% CI = 0.7-2.5) on which cigarette smoking (aOR = 7.1) exerts a stronger significant independent risk than alcohol drinking (aOR = 3.8). For pharyngeal cancers, chewers who consumed >20 quid/day, chewed with inflorescence in the quid or swallowed the betel quid juice were at higher risks; significant dose-response effects were found in daily quantity of drinking and chewing, and cumulative quantity of drinking. Synergistic effects from the 3 risk factors existed both on the pharynx (aOR = 96.9) and the larynx (aOR = 40.3), and attributed for 93.1% and 92.9% respectively. Our study is the first evidence to show that betel quid chewing without tobacco has different impact on the pharynx (digestive tract) and the larynx (airway), and supports the concept that exposure quantity and direct mucosal contact with the betel quid juice may contribute to carcinogenesis. Our results show an important insight into the impact of betel quid chewing on other sites of the digestive tract other than the oral cavity.

Adult↗
PubMed2005

Audiometric patterns and prognosis in sudden sensorineural hearing loss in southern Taiwan.

OBJECTIVES: To investigate factors affecting the prognosis of sudden sensorineural hearing loss (SSNHL). STUDY DESIGN AND SETTING: This is a retrospective study of patients with SSNHL hospitalized at an academic medical center. All patients in this study were treated with prednisolone and dextran. We compared a new 7-pattern classification for audiometric pattern and prognosis analysis with Sheehy classification. RESULTS: We analyzed 148 affected ears in 146 patients. Occurrence of SSNHL was associated with changes in season. The best prognosis was with the midtone pattern of the 7-pattern classification and with the low-tone pattern of Sheehy classification. The older patients, those with vertigo, or those treated after 6 days had a poor prognosis. There was no significant association between ESR level and prognosis. CONCLUSIONS: SSNHL patients with midtone loss have the best prognosis. This study of the audiometric patterns and prognostic factors of SSNHL allow us to better predict its outcome.

Adolescent↗
PubMed2005

Cerebral radionecrosis in patients with nasopharyngeal carcinoma.

This study involved seven patients with cerebral radionecrosis following radiation therapy for nasopharyngeal carcinoma (NPC). Their charts were reviewed and the relationship of extracranial malignancies to cerebral radionecrosis was investigated. The radiation dose ranged from 70 to 135 Gy, and the latency was from 6 to 39 months. Two of seven patients died of NPC-related complications during follow-up. The crude incidence of cerebral radionecrosis in patients with NPC was 0.93% in our series. Improvement of symptoms could be achieved by corticosteroid therapy, with or without surgery. In a review of the literature, there were 306 cases of cerebral radionecrosis in extracranial malignancies. The nasopharynx is the most common primary site in cerebral radionecrosis of extracranial malignancies, followed by the scalp and sinonasal tract. The 3-year overall survival rate in our series was 68.57%, as provided by the Kaplan-Meier product limited method. Cerebral radionecrosis in NPC patients should be differentiated from tumor recurrence, in order to apply the appropriate treatment.

Adult↗
PubMed2005

Giant rhinolith: a case report.

A rhinolith is a stone that forms in the nose. It occurs as a result of the solidification of mucus and nasal debris by mineral salts, calcium, magnesium phosphate and carbonate. It can be seen on radiographs as a radiopaque object in the nasal fossa and may be confused with several pathologic entities that will call for more invasive surgical procedures. We present the first case of a giant rhinolith, possibly arising from aspergillosis, and discuss its clinical and radiologic features.

Aspergillosis↗
PubMed2005

Treatment of laryngeal radionecrosis with hyperbaric oxygen therapy: a case report.

An 81-year-old male with early-stage laryngeal carcinoma had been treated with 60 Gy curative radiotherapy. He complained of a sore throat, foul odor in the mouth, progressive dyspnea, and fever 2 months after the completion of radiotherapy. Direct laryngoscopy revealed narrowing of the glottis with diffuse ulcerative necrotic tissue. Biopsies at multiple sites and pathology revealed intense coagulation necrosis with complete denudation of covering epithelium without any malignancy. Since laryngeal radionecrosis was suspected, the patient received hyperbaric oxygen (HBO) therapy 40 times for 1 hour of 100% O2 at 2 atm absolute pressure. His clinical symptoms gradually improved and repeated endolaryngeal biopsies were undertaken near the end of HBO therapy and again 6 months later. The patient's larynx healed completely with diffuse fibrosis and no malignant cells were found on pathology. Radionecrosis must be differentiated from cancer recurrence following curative radiotherapy for early laryngeal cancer. HBO therapy could be a useful treatment adjunct for laryngeal radionecrosis.

Aged↗
PubMed2005

Nasal septum chondroma: a case report.

Chondromas of the nasal septum are rare. Since its first literary description in 1842, only about 140 cases have been reported. We present the case of a 38-year-old female who reported intermittent nasal bleeding and nasal obstruction for 3 months. A reddish mass arising from the nasal septum was found by endoscope. The tumor was removed under endoscopic guidance and histopathologic examination revealed chondroma composed of well-differentiated chondrocytes. No recurrence was noticed after 6 months of follow-up. Despite their rarity, chondromas should be taken into consideration in the differential diagnosis of nasal tumors, especially those arising from the nasal septum.

Adult↗
PubMed2004

Incidence of dehiscence of the facial nerve at surgery for middle ear cholesteatoma.

OBJECTIVE: To identify the incidence of dehiscence of the facial nerve in patients undergoing surgery for cholesteatoma and to describe its relevance with iatrogenic facial nerve injury. STUDY DESIGN AND SETTING: This was a retrospective study including 117 tympanoplasties with or without mastoidectomy performed in 49 men and 66 women. RESULTS: The presences of FND after exenteration of disease are 33.3% of total surgical procedures, 33% of the initial procedures, and 37.5% of the revision procedures. The locations of facial nerve dehiscence were 87.2% in only the tympanic segment, 7.7% in only the vertical segment, and 5.1% in both the tympanic and vertical segments. CONCLUSIONS AND SIGNIFICANCE: The incidence of facial nerve dehiscence is high (33.3%) in our study. The surgeon should keep in mind that the location of facial nerve dehiscence with cholesteatoma is comparable with the most common area of iatrogenic facial nerve injury during otologic surgery.

Adolescent↗
PubMed2004

Epidermal growth factor expression in middle ear cholesteatoma.

Middle ear cholesteatoma is destructive to auditory ossicles and temporal bone, and treatment usually requires surgical removal of all epithelial content. Epidermal growth factor (EGF) can stimulate the growth and differentiation of a variety of mammalian cells, including epithelial cells. Our study used the avidin-biotin complex technique to evaluate the expression of EGF in 40 cases of middle ear cholesteatoma (active cholesteatoma, 31 cases; inactive cholesteatoma, 9 cases) and 34 normal postauricular skin samples. In middle ear cholesteatoma, EGF was expressed in squamous epithelium in 21 cases (53%), fibroblasts in two cases (5%), and cholesteatoma endothelium in two cases (5%). In normal postauricular skin, EGF was expressed in squamous epithelium in 14 samples (41%), fibroblasts in one sample (3%), and endothelium in none. No statistical difference in EGF expression was found between cholesteatoma and normal postauricular skin samples. These results show that the distribution of EGF in middle ear cholesteatoma is not deranged and that the progression of cholesteatoma might be induced by the release of factors from the cholesteatoma matrix via autocrine stimulation, or by inflammatory cells of the subepithelial tissue through paracrine stimulation, or in both of these ways.

Adult↗
PubMed2004

Fibro-osseous lesion of the external auditory canal: a case report.

The aim of this study was to differentiate a novel type of benign circumscribed bone lesion of the external auditory canal from lesions described previously, such as exostoses and osteomas. We present a 43-year-old male patient who suffered from ear discharge of the right ear. Local findings showed bloody discharge from his right auditory canal, which was occupied by a mass-like tissue. Computerized tomography (CT) carried out before resection of the lesion disclosed the absence of a bony connection to the underlying structures. The pathologic findings showed lesions consisting of an osteoma-like bone formation with sparse osteoblastic areas. Mature lamellar bone and bone marrow containing adipose tissue were also noted. There was no evidence of a relationship to the cartilaginous tissue or bony structures of the external auditory canal. Therefore, we present this rare case and review the reported literature in which clinical, CT, surgical, and pathologic findings suggest that this lesion was unlike those previously known, and may be related to ossifying reactions in other parts of the organism.

Adult↗
PubMed2004

Schwannoma of the nasal septum: a case report.

Schwannoma is a neurogenic tumor arising from the sheath of myelinated nerves. Only 4% of schwannomas located in the head and neck region involve the sinonasal tract, and those arising from the nasal septum are exceedingly rare. We report a case of a 55-year-old male who presented with only right nasal obstruction. Computerized tomography and clinical examination suggested a benign tumor before the tumor was completely removed by transnasal endoscopic surgery. When encountering a mass in the nasal cavity, schwannoma should be borne in mind in the differential diagnosis. We discuss the clinical presentation, histologic features, differential diagnosis, and therapeutic options for such a rare lesion.

Diagnosis, Differential↗
PubMed2004

Cerebral radionecrosis with cystic degeneration following radiotherapy for nasal cavity squamous cell carcinoma: a case report.

A 31-year-old man with nasal cavity squamous cell carcinoma was treated in our hospital with two courses of radiotherapy (120 Gy total dose) followed by surgical tumor resection. Three years after the last irradiation, he developed seizures as well as changes in behavior and consciousness. Medical therapy with diphenylhydantoin (Dilantin) terminated the seizures. Dysphagia, unsteady gait, and right-side limb weakness developed 37 months after the onset of seizures. Magnetic resonance imaging showed a large, cystic mass in the left temporal lobe with left to right midline shift. Following craniotomy with decompression of the cystic mass, the patient improved clinically. No malignant cells were found in the specimen. No further progression of neurologic symptoms was noted after a 1-year follow-up. Cerebral radionecrosis is an uncommon late complication of radiotherapy and needs to be differentiated from tumor recurrence or metastasis if the irradiation field covers the cerebral region in patients with head and neck malignancies.

Adult↗
PubMed2004

A long-term study on hearing status in patients with nasopharyngeal carcinoma after radiotherapy.

OBJECTIVE: To study the long-term sensorineural hearing status after radiotherapy in patients suffering from nasopharyngeal carcinoma. STUDY DESIGN: A prospective study of 220 patients (395 ears) with a median follow-up of 36 months. SETTING: A university hospital. PATIENTS: Four criteria were needed. The patient had to have had at least 12 months of audiologic follow-up, no concurrent chronic ear disease, no direct tumor invasion of ear, and no significant sensorineural hearing loss before radiotherapy. INTERVENTION: Pure-tone audiography and impedance audiometry-which were performed before and at the third month after completion of radiotherapy and at a yearly interval thereafter-formed the basis of the study. MAIN OUTCOME MEASURES: The significance level in this study was defined as a bone conduction threshold increase of more than 10 dB between the initial audiogram and those obtained after the completion of radiotherapy. An increase of more than 30 dB was defined as severe loss. RESULTS: Paired t test indicated that the mean bone conduction threshold before and after radiotherapy were significantly different (paired t test, p < 0.05). Logistic regression showed that patient age was related to the significant loss at speech frequency but not to the loss at 4 kHz. The presence of postradiation otitis media with effusion, preirradiation hearing status, and addition of chemotherapy were found to be not influential on hearing change. CONCLUSION: Hearing deterioration may begin as early as 3 months after the completion of radiotherapy. Early change may be transient, but the effect of radiation on hearing tended to be chronic and progressive.

Acoustic Impedance Tests↗
PubMed2004

Microsurgical pressing excision technique for vocal nodules and simple epithelial hyperplasia of the vocal fold.

Precise bimanual microsurgical excision of sessile, thin benign epithelial lesions of the vocal folds can be difficult. During microlaryngeal surgery, the potential risks of over-excision and under-excision are of major concern. We introduce a microsurgical technique using horizontally-opening curved microforceps and microscissors, instead of the conventional vertically-opening microinstruments, to remove vocal nodules and simple epithelial hyperplasia. The treatment results were satisfactory, with 208 (90.8 per cent) of patients retaining a satisfactory/normal (G(0)) voice. No patient had a worsened voice after the procedure. This microsurgical pressing excision technique is an alternative precise method for microlaryngosurgery.

Epithelium↗