The role of lateral pharyngoplasty in obstructive sleep apnea syndrome.

Recent studies have shown that lateral pharyngoplasty is an effective procedure to correct obstructive sleep apnea. The objective of the paper was to evaluate factors contributing to obstructive sleep apnea syndrome and identify the different severity categories of obstructive sleep apnea that could benefit from lateral pharyngoplasty. We included 60 patients undergoing uvulopalatopharyngoplasty with or without lateral pharyngoplasty from December 1, 2008 to May 31, 2012. Six who did not complete the post-operative survey were excluded. 54 participants were assigned alternatively to either uvulopalatopharyngoplasty alone (control group, n = 29) or to uvulopalatopharyngoplasty with lateral pharyngoplasty (intervention group, n = 25). The reduction of apnea-hypoxia index in the intervention group (49.3%) was higher than it was in the control group (30.4%), but the average value was not statistically significant (p = 0.088). Only patients with moderate obstructive sleep apnea in the intervention group achieved a significant reduction of apnea-hypoxia index (30.7 vs. 10.8%; p = 0.020). Factors such as body mass index, nadir/mean SpO2, snoring index, Epworth sleepiness scale and periodic limb movement index did not change significantly following lateral pharyngoplasty. To evaluate patients' upper airway anatomy, we employed cephalometry, and found that the retroglossal space played a critical role in severe obstructive sleep apnea. Our study showed that only patients in the moderate category can be benefited from adding lateral pharyngoplasty to uvulopalatopharyngoplasty; however, patients in the mild or severe category did not benefit from adding this procedure. This information is vital when considering surgery for patients with obstructive sleep apnea syndrome. Level of evidence Prospective cohort study, Level II.

T4-locally advanced nasopharyngeal carcinoma: prognostic influence of cranial nerve involvement in different radiotherapy techniques.

BACKGROUND: Cranial nerve involvement at disease presentation of nasopharyngeal carcinoma was not uncommon. We investigated the prognosis of patients with T4-locally advanced NPC, with or without cranial nerve involvement, and compared the outcome of patients treated using different radiotherapy techniques. METHODS: In this retrospective study, 83 T4-locally advanced NPC patients were diagnosed according to the seventh edition of the American Joint Committee on Cancer staging system. All patients were treated using three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiation therapy (IMRT). The survival rate was analyzed using the Kaplan-Meier method. RESULTS: The 5-year overall, locoregional-free, and disease-free survival rates of patients treated using IMRT were 88.9%, 75.2%, and 69.2%, respectively. The outcome in these patients was significantly better than that in patients treated using 3D-CRT, with survival rates of 58.2%, 54.4%, and 47.2%, respectively. There was no significant difference in the 5-year overall, locoregional-free, and disease-free survival rates of the patients with (64.2%, 60.5%, and 53.5%, resp.) and without (76.9%, 63.6%, and 57.6%, resp.) cranial nerve involvement. CONCLUSION: Locally advanced NPC patients treated using IMRT had significantly better outcomes than patients treated using 3D-CRT. Our results showed that the outcome of T4 NPC patients with or without cranial nerve involvement was not different.

Heart rate variability analysis in patients with allergic rhinitis.

BACKGROUND: Very few studies investigate the role of the autonomic nervous system in allergic rhinitis. In this study, we evaluated the autonomic nervous system in allergic rhinitis patients using heart rate variability (HRV) analysis. METHODS: Eleven patients with allergic rhinitis and 13 healthy controls, aged between 19 and 40 years old, were enrolled in the study. Diagnosis of allergic rhinitis was based on clinical history, symptoms, and positive Phadiatop test. Electrocardiographic recordings on the sitting and supine positions were obtained for HRV analysis. RESULTS: In the supine position, there were no significant statistical differences in very-low-frequency power (VLF, ≤0.04 Hz), low-frequency power (LF, 0.04-0.15 Hz), high-frequency power (HF, 0.15-0.40 Hz), and the ratio of LF to HF (LF/HF) between the patient and control groups. The mean RR intervals significantly increased, while LF% and LF/HF significantly decreased in the patient group in the sitting position. Moreover, mean RR intervals, LF, and LF/HF, which were significantly different between the two positions in the control group, did not show a significant change with the posture change in the patient group. CONCLUSION: These suggest that patients with allergic rhinitis may have poor sympathetic modulation in the sitting position. Autonomic dysfunction may therefore play a role in the pathophysiology of allergic rhinitis.

Exogenous FGF-1 Differently Regulates Oligodendrocyte Replenishment in an SCI Repair Model and Cultured Cells.

We studied the phenotypes in an oligodendrocyte genesis site at the acute stage of spinal cord injury, when we observed regenerated ascending neurites. Pan-oligodendrocyte marker OLIG2+ cells were more in fibroblast growth factor (FGF)-1-treated rats (F group) than in non-treated (T group) in this site, while the number of NG2+OX42- oligodendrocyte progenitor cell (OPC), CNPase+ OPC, Nkx2.2+ OPC, and APC+ remyelinating oligodendrocytes was less in the F group. Paradoxically, when we label the rats with pulsed bromodeoxyuridine (BrdU), we found that the mitotic NKX2.2+ OPC cells are more in the F group than in the T group. We tested the embryonic spinal cord mixed culture. FGF treatment resulted in more NG2(+) CNPase (+) than non-FGF-1-treated culture, while the more mature NG2(-) CNPase(+) cell numbers were reduced. When we block the FGF receptor in the injured rat model, the NG2+OX42- cell numbers were increased to be comparable to non-FGF-1 rats, while this failed to bring back the APC+ mature oligodendrocyte cell numbers. As migration of OPC toward injury is a major factor that was absent from the cell culture, we tested 8 mm away from the injury center, and found there were more NG2+ cells with FGF-1 treatment. We proposed that it was possibly a combination of migration and proliferation that resulted in a reduction in the NG2+ OPC population at the oligodendrocyte genesis site when FGF-1 was added to the spinal cord injury in vivo.

Pretreatment age and serum lactate dehydrogenase as predictors of synchronous second primary cancer in patients with nasopharyngeal carcinoma.

OBJECTIVES: Nasopharyngeal carcinoma (NPC) is a common cancer and is treated primarily by chemotherapy and radiotherapy. However, NPC with synchronous second primary cancer (SSPC) is very rare and its risk factors, treatment and prognosis remain unclear. In this study, we aimed to analyze patients with NPC and SSPC, and attempt to find potential predictors for these patients. MATERIALS AND METHODS: We retrospectively collected 681 patients with NPC from 2006 to 2018. Patients in this study were divided into two groups: those patients with SSPC and those without SSPC. We then analyzed the demographic data and survival of these two groups. Independent predictors of SSPC were determined by multivariate regression analysis. A comprehensive review of the literature was also performed. RESULTS: We identified 17 NPC patients with SSPC in our case series and 13 cases in the literatures, and the most common SSPC is lung (16.1%). In univariate analysis, NPC patients with SSPC had older age (P < 0.001) and higher serum lactate dehydrogenase (LDH) (P = 0.008), compared with those without SSPC. In multivariate analysis, old age (P = 0.001) and high serum LDH (P = 0.023) remained independent predictors of SSPC, and a predictive equation model was established. NPC patients with SSPC had a significantly lower 5-year disease-specific survival rate compared with patients without SSPC (34.0% vs. 77.6%, P < 0.001) CONCLUSION: This study demonstrated that pretreatment age and serum LDH were independent predictors for SSPC in NPC patients. These independent factors can be used for early detection, and better facilitate the design of more appropriate treatment by medical professionals.

Survey of the frequency of olfactory dysfunction in Taiwan.

BACKGROUND: Olfactory function is related to the scrutiny of environmental dangers and the tasting of food. However, olfactory dysfunction is not as distinctive as visual loss and may go unnoticed, especially when olfactory function deteriorates slowly. Most studies have used either questionnaires or relatively insensitive tests to assess olfactory dysfunction. Therefore, the objective of this study was to evaluate the frequency of olfactory dysfunction in Taiwan. METHODS: A total of 211 participants were recruited randomly from the community, factories or offices in Taichung City, Taiwan from April 2005 to March 2006. Age ranged from 19 to 89 years (mean age, 43.3 +/- 12.7 years). All participants filled in questionnaires about sociodemographic data, self-rated olfactory function and impact on quality of life. The olfactory test was performed with identification task of the "Sniffin' Sticks" olfactory function test. RESULTS: The frequency of olfactory dysfunction in our series was 12.3%. There was a statistically significant difference in the ages of the normal and olfactory dysfunction groups (t test, p < 0.0001). The incidences of parosmia and phantosmia in the 211 participants were 10% and 30.8%, respectively. Most subjects did not rate their olfactory function well. There was no correlation between olfactory function and self-ratings of impact of olfactory function on quality of life. CONCLUSION: Our present results provide preliminary data and clinical experience regarding the frequency of olfactory dysfunction in Taiwan. Future modifications and suggestions for the study of the prevalence of olfactory dysfunction are also mentioned.

Toward a better understanding of sinonasal mucosal melanoma: clinical review of 23 cases.

BACKGROUND: Primary sinonasal mucosal melanoma is a rare disease, occurring far less often than cutaneous lesions. The objective of this study was to review the records of patients diagnosed with primary sinonasal mucosal melanoma. METHODS: We performed a retrospective review of the medical records of 23 patients with sinonasal mucosal melanoma who were treated at Taipei Veterans General Hospital between 1982 and 2002. RESULTS: Sixteen of the 23 patients were male and 7 were female; their mean age was 68.2 years (range, 39-87 years). At diagnosis, the melanoma was limited to lesions located in the sinonasal area in 20 patients, and had spread in 3 patients. Local recurrence developed in 9 patients, neck metastasis in 5, and distant metastasis in 19. The 5-year disease-specific survival and local control rates were 22.26% and 52.30%, respectively. CONCLUSION: In our experience, primary sinonasal mucosa melanoma is prone to spread from the site of origin. The major obstacle in improving overall survival is achieving systemic control.

Association of p53 codon 72 polymorphism with risk of hypopharyngeal squamous cell carcinoma in Taiwan.

BACKGROUND: p53 polymorphism at codon 72 is a known risk marker for various malignancies, but it has not been studied in hypopharyngeal cancer. This study investigated the genotype distribution of p53 codon 72 polymorphism in hypopharyngeal cancer patients and non-cancer controls matched for age, gender, alcohol consumption and smoking habit. METHODS: Genomic DNA was extracted from peripheral blood cells of 53 patients with hypopharyngeal cancer and 53 non-cancer controls. Codon 72 polymorphism of p53 was identified by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: Patients with hypopharyngeal cancer had higher frequencies of Pro/Pro (26.4% vs. 13.2%) and Pro/Arg (51.0% vs. 45.3%) but lower frequencies of Arg/Arg (22.6% vs. 45.1%) compared to controls. Compared to Arg/Arg genotypes, Pro/Pro genotypes had a relative risk of hypopharyngeal cancer of 3.667 (95% confidence interval, 1.16-11.56; p = 0.03). As a group, patients with Pro/Pro or Arg/Pro who were carriers of the Pro allele had a higher relative risk of hypopharyngeal cancer compared to Arg homozygous carriers (odds ratio, 2.415; 95% confidence interval, 1.04-5.64; p = 0.04). CONCLUSION: This study demonstrated that p53 codon 72 Pro homozygosity is associated with a higher risk of developing hypopharyngeal cancer.

Twice-daily application of topical corticosteroids with a squirt system for patients with steroid-responsive olfactory impairment.

CONCLUSION: Twice-daily topical corticosteroid treatment using a squirt system was beneficial in maintaining improvements in olfactory dysfunction which had been achieved by oral steroid treatment. OBJECTIVES: Some patients suffering from olfactory dysfunction respond well to corticosteroids. However, maintaining these improvements is challenging. The aim of this study was to evaluate the maintenance effect of twice-daily topical steroid treatment using a squirt system. METHODS: Twenty-two anosmic patients with an increase in odor threshold, discrimination, and identification (TDI) scores in Sniffin' Sticks tests by more than six points after 1-week of oral steroid treatment were enrolled. All the patients used a squirt system to apply topical corticosteroids and were followed up at 1, 3, and 6 months. RESULTS: Nineteen, 16, and 10 patients were followed-up at 1, 3, and 6 months after treatment, respectively. All the patients had significant visual analog scale scores improvements compared to pre-treatment. The mean improvements in TDI scores were 9.80 (p < 0.001), 11.58 (p = 0.001), and 13.87 (p = 0.005) after 1, 3, and 6 months of treatment, respectively. The self-rated and objective olfactory function scores were maintained with steroid squirt therapy without significant decline, even in the patients who were followed up for 6 months.

Serotnin as a possible biomarker in obstructive sleep apnea.

Obstructive sleep apnea (OSA) is a highly prevalent disease which carries substantial public health burden. Polysomnography is the standard procedure used to diagnose OSA. However cost, accessibility, technical requirements, and skilled interpretation needs constrain its widespread use and have a role in the under-diagnosis of sleep disordered breathing. There is a clinical need to develop expedient and widely accessible tools to detect this disorder., Several biochemical markers have recently been proposed as diagnostic tools in OSA. Numerous neurochemicals directly influence the activity of upper airway dilator motor neurons, which subsequently influence respiration during sleep. Serotonin (5-HT) is one such neurochemical that has a key role in ventilatory stimulation. Herein, we review the current evidence demonstrating relationships between multiple biomarkers and sleep disordered breathing and focus on relationships between OSA and 5-HT. We discuss the possibility of biomarker-driven detection technology in the future as a means of diagnosing and monitoring OSA. Finally, we explore the specific role 5-HT may have in the future in both the diagnosis and treatment of OSA.

CD44 and CD24 coordinate the reprogramming of nasopharyngeal carcinoma cells towards a cancer stem cell phenotype through STAT3 activation.

Cell surface proteins such as CD44 and CD24 are used to distinguish cancer stem cells (CSCs) from the bulk-tumor population. However, the molecular functionalities of CD24 and CD44, and how these two molecules coordinate in CSCs remain poorly understood. We found that nasopharyngeal carcinoma (NPC) cells with high expression of CD44 and CD24 proteins presented with pronounced CSC properties. Accordingly, a subpopulation of NPC cells with co-expression of CD44 and CD24 were specially enriched in high-stage clinical samples. Furthermore, ectopically expressing the epithelial-mesenchymal transition (EMT) regulator Twist was able to upregulate the stemness factors, and vice versa. This indicates a reciprocal regulation of stemness and EMT. Intriguingly, we found that this reciprocal regulation was differentially orchestrated by CD44 and CD24, and only simultaneous silencing the expression of CD44 and CD24 led to a broad-spectrum suppression of CSC properties. Oppositely, overexpression of CD44 and CD24 induced the reprogramming of parental NPC cells into CSCs through STAT3 activation, which could be blunted by STAT3 inhibition, indicating that CD44 and CD24 collaboratively drive the reprogramming of NPC cells through STAT3-mediated stemness and EMT activation. Consequently, targeting of the CD44/CD24/STAT3 axis may provide a potential therapeutic paradigm for the treatment of NPC through repressing CSC activities.

Epithelioid hemangioendothelioma of the nasal cavity.

Epithelioid hemangioendothelioma (EH) is an unusual vascular neoplasm characterized by proliferation of endothelial cells with epithelioid morphology. It has an indolent course, with the potential for recurrence, but rarely metastasizes. The common locations include soft tissue, skin, viscera and bone. We present an unusual case of EH in the nasal cavity and describe the clinical characteristics, histopathologic findings, differential diagnosis and management. The 25-year-old male patient initially presented with an 8-month history of intermittent epistaxis. Nasal endoscopy revealed a vascular tumor involving the nasal cavity. The tumor was excised and the final histopathologic diagnosis was consistent with EH. EH in the head and neck is extremely rare. Wide excision is the treatment of choice, and regular follow-up is suggested due to the potential for recurrence. Definitive diagnosis depends on histopathologic and immunohistochemical features.

Investigation of prognostic factors for post-traumatic olfactory dysfunction.

BACKGROUND: Post-traumatic olfactory dysfunction is common but has a poor prognosis. The purpose of this study was to analyze the effect of clinical features on improvements in post-traumatic olfactory dysfunction. METHODS: From 2007 to 2013, patients with post-traumatic olfactory dysfunction were enrolled. Olfactory function was assessed using the Sniffin' Sticks test at the first and final visits. Olfactory improvement was defined as a change in olfactory state to an improved level. Variables with a potential effect on improvements in olfactory dysfunction, including age, sex, time from trauma to first visit, initial olfactory function, observation time, and olfactory bulb integrity, were entered into logistic regression analysis. RESULTS: In total, 107 patients were included, with a mean age of 40 years. The mean follow-up period was 9.4 months. Eighteen patients (16.8%) had improvements with regard to olfactory function. No clinical factors were found to influence olfactory recovery in univariate and multivariate analyses (all p > 0.05). In addition, there were no differences in clinical features between the patients with and without olfactory recovery (all p > 0.05). CONCLUSION: No significantly favorable prognostic factors for post-traumatic olfactory recovery were identified, reflecting, to some extent, the poor prognosis of post-traumatic olfactory damage. The results of this study provide useful information that clinical physicians can use when counseling patients with post-traumatic olfactory disorder regarding the prognosis, observation choice, and possible treatment strategy.

Nasopharyngeal lymphoid hyperplasia of an HIV carrier, mimicking nasopharyngeal cancer.

Lymphoid hyperplasia of cervical lymph nodes is a common head and neck presentation of human immunodeficiency virus (HIV) infection. Lymphoid hyperplasia of HIV carrier presenting as nasopharyngeal tumor and neck mass is rarely discussed. We reported a 30-year-old male patient who had left side neck mass for 3 months. Nasopharyngeal cancer with neck metastasis was impressed due to huge nasopharyngeal tumor and neck mass. The patient was then transferred to our clinic for further evaluation. Physical examination revealed a 30 x 30 mm mass over left jugulodigastric area and a 20 x 20 mm mass over left posterior triangle of neck. Telescopic examination revealed a 20 x 20 mm bulging mass over nasopharynx. Nasopharyngeal biopsy was done and histopathologic examination revealed lymphoid hyperplasia. Laboratory survey showed seropositive of HIV infection for both enzyme-linked immunosorbent assay (ELISA) and western blot tests.

Evaluating the autonomic nervous system in patients with laryngopharyngeal reflux.

OBJECTIVES: The pathogenesis of laryngopharyngeal reflux (LPR) remains unclear. It is linked to but distinct from gastroesophageal reflux disease (GERD), which has been shown to be related to disturbed autonomic regulation. The aim of this study is to investigate whether autonomic dysfunction also plays a role in the pathogenesis of LPR. STUDY DESIGN: Case-control study. SETTING: Tertiary care center. SUBJECTS AND METHODS: Seventeen patients with LPR and 19 healthy controls, aged between 19 and 50 years, were enrolled in the study. The patients were diagnosed with LPR if they had a reflux symptom index (RSI) ≥ 13 and a reflux finding score (RFS) ≥ 7. Spectral analysis of heart rate variability (HRV) analysis was used to assess autonomic function. Anxiety and depression levels measured by the Beck Anxiety Inventory (BAI) and Beck Depression Inventory II (BDI-II) were also conducted. RESULTS: In HRV analysis, high frequency (HF) represents the parasympathetic activity of the autonomic nervous system, whereas low frequency (LF) represents the total autonomic activity. There were no significant differences in the LF power and HF power between the 2 groups. However, significantly lower HF% (P = .003) and a higher LF/HF ratio (P = .012) were found in patients with LPR, who demonstrated poor autonomic modulation and higher sympathetic activity. Anxiety was also frequently observed in the patient group. CONCLUSION: The study suggests that autonomic dysfunction seems to be involved in the pathogenesis of LPR. The potential beneficial effect of autonomic nervous system modulation as a therapeutic modality for LPR merits further investigation.

Topical corticosteroids applied with a squirt system are more effective than a nasal spray for steroid-dependent olfactory impairment.

OBJECTIVES/HYPOTHESIS: Oral corticosteroids may restore conductive olfactory dysfunction that has been defined as steroid-dependent olfactory loss, but the effect may be temporary. This study was designed to evaluate whether applying topical corticosteroids with a squirt system was more effective than using a nasal spray to maintain olfactory improvement following oral corticosteroids. STUDY DESIGN: Prospective randomized trial enrolling 32 patients. METHODS: Patients were enrolled if they had suffered from olfactory dysfunction for more than 3 months, and if their composite scores of odor threshold, discrimination, and identification scores in Sniffin' Sticks olfactory tests increased by more than six points after 1 week of oral corticosteroid treatment. A total of 32 patients were enrolled and randomized into two groups. All patients were treated with topical corticosteroids for 2 months using either the spray or squirt system, respectively. RESULTS: Both measured and self-rated olfactory functions after 1 and 2 months of topical corticosteroid treatment were better in the squirt group than in the spray group. However, 2 months of topical corticosteroid treatment with the squirt system only partially maintained olfactory improvement. CONCLUSIONS: The application of topical corticosteroids with a squirt system was more effective than with a spray in maintaining olfactory improvement with oral corticosteroid treatment. Nevertheless, it only partially maintained the improvement so that topical corticosteroid treatment using a squirt system needs to be combined with intervals of short-term oral corticosteroids to treat steroid-dependent olfactory loss while avoiding the side effects of long-term oral corticosteroid use.

Sino-nasal neuro-endocrine carcinoma.

CONCLUSION: Patients with sino-nasal neuro-endocrine carcinoma should be managed by multi-modality treatment that includes surgery and postoperative chemo-radiotherapy as described in our treatment plan. Even though current combined therapy results in good disease control and survival rate, long-term follow-up is necessary. OBJECTIVE: Neuro-endocrine carcinoma is an aggressive and rare malignant tumor of the sino-nasal tract, and its management remains divergent. The aim of this paper is to present our experience in the management of this kind of aggressive tumor and compare different treatment plans in order to draw up an effective strategy. Various treatment strategies were reviewed and assessed. METHODS: Seven patients with biopsy-proven primary sino-nasal neuro-endocrine carcinoma from July 2004 to December 2006 were evaluated. The staging system was based on the American Joint Committee on Cancer Staging Manual of 2002. All of the patients underwent endoscopic or open surgery with curative intent. Six patients received postoperative chemo-radiotherapy. RESULTS: The median follow-up after surgery was 43.5 months (range 26.9-57.7 months). One patient was T2N0M0, one was T3N0M0, four were T4aN0M0, and one was T4bN0M0. After endoscopic or open surgery and postoperative chemo-radiotherapy, six patients were alive with no evidence of recurrence. One patient had persistent tumor without clinical and imaging changes for 36.9 months. After the whole treatment course, one patient had sino-cutaneous fistula and underwent flap reconstruction. None had regional failure or distant metastasis during follow-up.

Investigation of the Sniffin' Sticks olfactory test in Taiwan and comparison with different continents.

BACKGROUND: The Sniffin' Sticks test is a well-developed olfactory test, with normative data having been derived from more than 3,000 subjects in central-northern Europe and Australia. However, as environment affects olfactory function, the purposes of this study were to establish normative data for the Sniffin' Sticks olfactory test in Taiwan, where the climate is different from that of Europe, and to determine whether or not the olfactory function of Taiwanese is different from that of Europeans. METHODS: One hundred and forty-five subjects with normal self-rated olfactory function were enrolled. The Sniffin' Sticks olfactory test was used to score olfactory threshold (OT), odor discrimination (OD) and odor identification (OI), and a composite TDI score was calculated. RESULTS: All of the tasks related to the Sniffin' Sticks olfactory test correlated significantly and inversely with age. The 10(th) percentiles of OT, OD, OI and TDI in the 16-35 years age group were 4.50, 9.70, 12.00 and 30.00, respectively. These data were the criteria used to separate normosmia from hyposmia. CONCLUSION: The diagnostic criteria to separate normosmia from hyposmia in Taiwan are similar to those in Europe.

An SSVEP-actuated brain computer interface using phase-tagged flickering sequences: a cursor system.

This study presents a new steady-state visual evoked potential (SSVEP)-based brain computer interface (BCI). SSVEPs, induced by phase-tagged flashes in eight light emitting diodes (LEDs), were used to control four cursor movements (up, right, down, and left) and four button functions (on, off, right-, and left-clicks) on a screen menu. EEG signals were measured by one EEG electrode placed at Oz position, referring to the international EEG 10-20 system. Since SSVEPs are time-locked and phase-locked to the onsets of SSVEP flashes, EEG signals were bandpass-filtered and segmented into epochs, and then averaged across a number of epochs to sharpen the recorded SSVEPs. Phase lags between the measured SSVEPs and a reference SSVEP were measured, and targets were recognized based on these phase lags. The current design used eight LEDs to flicker at 31.25 Hz with 45 degrees phase margin between any two adjacent SSVEP flickers. The SSVEP responses were filtered within 29.25-33.25 Hz and then averaged over 60 epochs. Owing to the utilization of high-frequency flickers, the induced SSVEPs were away from low-frequency noises, 60 Hz electricity noise, and eye movement artifacts. As a consequence, we achieved a simple architecture that did not require eye movement monitoring or other artifact detection and removal. The high-frequency design also achieved a flicker fusion effect for better visualization. Seven subjects were recruited in this study to sequentially input a command sequence, consisting of a sequence of eight cursor functions, repeated three times. The accuracy and information transfer rate (mean +/- SD) over the seven subjects were 93.14 +/- 5.73% and 28.29 +/- 12.19 bits/min, respectively. The proposed system can provide a reliable channel for severely disabled patients to communicate with external environments.

The proportion of self-rated olfactory dysfunction does not change across the life span.

BACKGROUND: Previous reports indicated that self-reports of olfactory function are unreliable. The occurrence of measured olfactory dysfunction is approximately 20% in the general population and consistently higher than that of self-reported olfactory dysfunction. To further understand the frequencies of self-rated olfactory function in different age groups and its relation with measured olfactory function, a prospective investigation of self-rated and measured olfactory function was performed. METHODS: One thousand five subjects were enrolled from the health care center, where subjects underwent a physical checkup for possible preclinical diseases. The subjects completed a questionnaire about demographic data and medical and surgical histories and self-rated their olfactory function. Then, they received a modified "Sniffin' Sticks" odor identification test. RESULTS: The self-rated olfaction function did not correlate significantly with measured olfactory function. The frequencies of self-rated olfactory dysfunction (9-14%) were similar among various age groups. However, the frequencies of measured olfactory dysfunction in the three age groups, i.e., 18 to 35, 36 to 55, and > 55 years, were 3.7%, 17.4%, and 35.6%, respectively. CONCLUSIONS: Self-ratings of olfactory function were unreliable at all ages. The frequencies of self-rated olfactory function in various age groups did not differ significantly, in contrast to the decrease of measured olfactory function with age.