Digital neuropsychological measures by defense automated neurocognitive assessment: reference values and clinical correlates

Introduction

Although the growth of digital tools for cognitive health assessment, there's a lack of known reference values and clinical implications for these digital methods. This study aims to establish reference values for digital neuropsychological measures obtained through the smartphone-based cognitive assessment application, Defense Automated Neurocognitive Assessment (DANA), and to identify clinical risk factors associated with these measures.

Methods

The sample included 932 cognitively intact participants from the Framingham Heart Study, who completed at least one DANA task. Participants were stratified into subgroups based on sex and three age groups. Reference values were established for digital cognitive assessments within each age group, divided by sex, at the 2.5th, 25th, 50th, 75th, and 97.5th percentile thresholds. To validate these values, 57 cognitively intact participants from Boston University Alzheimer's Disease Research Center were included. Associations between 19 clinical risk factors and these digital neuropsychological measures were examined by a backward elimination strategy.

Results

Age- and sex-specific reference values were generated for three DANA tasks. Participants below 60 had median response times for the Go-No-Go task of 796 ms (men) and 823 ms (women), with age-related increases in both sexes. Validation cohort results mostly aligned with these references. Different tasks showed unique clinical correlations. For instance, response time in the Code Substitution task correlated positively with total cholesterol and diabetes, but negatively with high-density lipoprotein and low-density lipoprotein cholesterol levels, and triglycerides.

Discussion

This study established and validated reference values for digital neuropsychological measures of DANA in cognitively intact white participants, potentially improving their use in future clinical studies and practice.

Comparing Cognitive Tests and Smartphone-Based Assessment in 2 US Community-Based Cohorts

BACKGROUND

Smartphone-based cognitive assessments have emerged as promising tools, bridging gaps in accessibility and reducing bias in Alzheimer disease and related dementia research. However, their congruence with traditional neuropsychological tests and usefulness in diverse cohorts remain underexplored.

METHODS AND RESULTS

A total of 406 FHS (Framingham Heart Study) and 59 BHS (Bogalusa Heart Study) participants with traditional neuropsychological tests and digital assessments using the Defense Automated Neurocognitive Assessment (DANA) smartphone protocol were included. Regression models investigated associations between DANA task digital measures and a neuropsychological global cognitive Z score (Global Cognitive Score [GCS]), and neuropsychological domain-specific Z scores. FHS participants' mean age was 57 (SD, 9.75) years, and 44% (179) were men. BHS participants' mean age was 49 (4.4) years, and 28% (16) were men. Participants in both cohorts with the lowest neuropsychological performance (lowest quartile, GCS1) demonstrated lower DANA digital scores. In the FHS, GCS1 participants had slower average response times and decreased cognitive efficiency scores in all DANA tasks (P<0.05). In BHS, participants in GCS1 had slower average response times and decreased cognitive efficiency scores for DANA Code Substitution and Go/No-Go tasks, although this was not statistically significant. In both cohorts, GCS was significantly associated with DANA tasks, such that higher GCS correlated with faster average response times (P<0.05) and increased cognitive efficiency (all P<0.05) in the DANA Code Substitution task.

CONCLUSIONS

Our findings demonstrate that smartphone-based cognitive assessments exhibit concurrent validity with a composite measure of traditional neuropsychological tests. This supports the potential of using smartphone-based assessments in cognitive screening across diverse populations and the scalability of digital assessments to community-dwelling individuals.

Design and Feasibility Analysis of a Smartphone-Based Digital Cognitive Assessment Study in the Framingham Heart Study

BACKGROUND

Smartphone-based digital technology is increasingly being recognized as a cost-effective, scalable, and noninvasive method of collecting longitudinal cognitive and behavioral data. Accordingly, a state-of-the-art 3-year longitudinal project focused on collecting multimodal digital data for early detection of cognitive impairment was developed.

METHODS AND RESULTS

A smartphone application collected 2 modalities of cognitive data, digital voice and screen-based behaviors, from the FHS (Framingham Heart Study) multigenerational Generation 2 (Gen 2) and Generation 3 (Gen 3) cohorts. To understand the feasibility of conducting a smartphone-based study, participants completed a series of questions about their smartphone and app use, as well as sensory and environmental factors that they encountered while completing the tasks on the app. Baseline data collected to date were from 537 participants (mean age=66.6 years, SD=7.0; 58.47% female). Across the younger participants from the Gen 3 cohort (n=455; mean age=60.8 years, SD=8.2; 59.12% female) and older participants from the Gen 2 cohort (n=82; mean age=74.2 years, SD=5.8; 54.88% female), an average of 76% participants agreed or strongly agreed that they felt confident about using the app, 77% on average agreed or strongly agreed that they were able to use the app on their own, and 81% on average rated the app as easy to use.

CONCLUSIONS

Based on participant ratings, the study findings are promising. At baseline, the majority of participants are able to complete the app-related tasks, follow the instructions, and encounter minimal barriers to completing the tasks independently. These data provide evidence that designing and collecting smartphone application data in an unsupervised, remote, and naturalistic setting in a large, community-based population is feasible.

Shifting From Active to Passive Monitoring of Alzheimer Disease: The State of the Research

Most research using digital technologies builds on existing methods for staff-administered evaluation, requiring a large investment of time, effort, and resources. Widespread use of personal mobile devices provides opportunities for continuous health monitoring without active participant engagement. Home-based sensors show promise in evaluating behavioral features in near real time. Digital technologies across these methodologies can detect precise measures of cognition, mood, sleep, gait, speech, motor activity, behavior patterns, and additional features relevant to health. As a neurodegenerative condition with insidious onset, Alzheimer disease and other dementias (AD/D) represent a key target for advances in monitoring disease symptoms. Studies to date evaluating the predictive power of digital measures use inconsistent approaches to characterize these measures. Comparison between different digital collection methods supports the use of passive collection methods in settings in which active participant engagement approaches are not feasible. Additional studies that analyze how digital measures across multiple data streams can together improve prediction of cognitive impairment and early-stage AD are needed. Given the long timeline of progression from normal to diagnosis, digital monitoring will more easily make extended longitudinal follow-up possible. Through the American Heart Association-funded Strategically Focused Research Network, the Boston University investigative team deployed a platform involving a wide range of technologies to address these gaps in research practice. Much more research is needed to thoroughly evaluate limitations of passive monitoring. Multidisciplinary collaborations are needed to establish legal and ethical frameworks for ensuring passive monitoring can be conducted at scale while protecting privacy and security, especially in vulnerable populations.

Adherence type impacts completion rates of frequent mobile cognitive assessments among older adults with and without cognitive impairment

Background

Prior to a diagnosis of Alzheimer's disease, many individuals experience cognitive and behavioral fluctuations that are not detected during a single session of traditional neuropsychological assessment. Mobile applications now enable high-frequency cognitive data to be collected remotely, introducing new opportunities and challenges. Emerging evidence suggests cognitively impaired older adults are capable of completing mobile assessments frequently, but no study has observed whether completion rates vary by assessment frequency or adherence type.

Methods

Thirty-three older adults were recruited from the Boston University Alzheimer's Disease Research Center (mean age = 73.5 years; 27.3% cognitively impaired; 57.6% female; 81.8% White, 18.2% Black). Participants remotely downloaded and completed the DANA Brain Vital application on their own mobile devices throughout the study. The study schedule included seventeen assessments to be completed over the course of a year. Specific periods during which assessments were expected to be completed were defined as subsegments, while segments consisted of multiple subsegments. The first segment included three subsegments to be completed within one week, the second segment included weekly subsegments and spanned three weeks, and the third and fourth segments included monthly subsegments spanning five and six months, respectively. Three distinct adherence types - subsegment adherence, segment adherence, and cumulative adherence - were examined to determine how completion rates varied depending on assessment frequency and adherence type.

Results

Adherence type significantly impacted whether the completion rates declined. When utilizing subsegment adherence, the completion rate significantly declined (p = 0.05) during the fourth segment. However, when considering completion rates from the perspective of segment adherence, a decline in completion rate was not observed. Overall adherence rates increased as adherence parameters were broadened from subsegment adherence (60.6%) to segment adherence (78.8%), to cumulative adherence (90.9%).

Conclusions

Older adults, including those with cognitive impairment, are able to complete remote cognitive assessments at a high-frequency, but may not necessarily adhere to prescribed schedules.

Examination of potentially modifiable dementia risk factors across the adult life course: The Framingham Heart Study

INTRODUCTION

We examined for associations between potentially modifiable risk factors across the adult life course and incident dementia.

METHODS

Participants from the Framingham Heart Study were included (n = 4015). Potential modifiable risk factors included education, alcohol intake, smoking, body mass index (BMI), physical activity, social network, diabetes, and hypertension. Cox models were used to examine associations between each factor and incident dementia, stratified by early adult life (33-44 years), midlife (45-65 years), and late life (66-80 years).

RESULTS

Increased dementia risk was associated with diabetes (hazard ratio [HR] = 1.62; 95% confidence interval [CI] = 1.07-2.46) and physical inactivity (HR = 1.57; 95% CI = 1.12-2.20) in midlife, and with obesity (HR = 1.76; 95% CI = 1.08-2.87) in late life. Having multiple potential modifiable risk factors in midlife and late life was associated with greater risk.

DISCUSSION

Potentially modifiable risk factors individually have limited impact on dementia risk in this population across the adult life course, although in combination they may have a synergistic effect.

HIGHLIGHTS

Diabetes and physical inactivity in midlife is associated with increased dementia risk. Obesity in late life is associated with increased dementia risk. Having more potentially modifiable risk factors in midlife and late life is associated with greater dementia risk.

Matching science to reality: how to deploy a participant-driven digital brain health platform

Introduction

Advances in digital technologies for health research enable opportunities for digital phenotyping of individuals in research and clinical settings. Beyond providing opportunities for advanced data analytics with data science and machine learning approaches, digital technologies offer solutions to several of the existing barriers in research practice that have resulted in biased samples.

Methods

A participant-driven, precision brain health monitoring digital platform has been introduced to two longitudinal cohort studies, the Boston University Alzheimer's Disease Research Center (BU ADRC) and the Bogalusa Heart Study (BHS). The platform was developed with prioritization of digital data in native format, multiple OS, validity of derived metrics, feasibility and usability. A platform including nine remote technologies and three staff-guided digital assessments has been introduced in the BU ADRC population, including a multimodal smartphone application also introduced to the BHS population. Participants select which technologies they would like to use and can manipulate their personal platform and schedule over time.

Results

Participants from the BU ADRC are using an average of 5.9 technologies to date, providing strong evidence for the usability of numerous digital technologies in older adult populations. Broad phenotyping of both cohorts is ongoing, with the collection of data spanning cognitive testing, sleep, physical activity, speech, motor activity, cardiovascular health, mood, gait, balance, and more. Several challenges in digital phenotyping implementation in the BU ADRC and the BHS have arisen, and the protocol has been revised and optimized to minimize participant burden while sustaining participant contact and support.

Discussion

The importance of digital data in its native format, near real-time data access, passive participant engagement, and availability of technologies across OS has been supported by the pattern of participant technology use and adherence across cohorts. The precision brain health monitoring platform will be iteratively adjusted and improved over time. The pragmatic study design enables multimodal digital phenotyping of distinct clinically characterized cohorts in both rural and urban U.S. settings.

Midlife Neuropsychological Profiles and Associated Vascular Risk: The Bogalusa Heart Study

BACKGROUND

Individuals with Alzheimer's disease (AD) often present with coexisting vascular pathology that is expressed to different degrees and can lead to clinical heterogeneity.

OBJECTIVE

To examine the utility of unsupervised statistical clustering approaches in identifying neuropsychological (NP) test performance subtypes that closely correlate with carotid intima-media thickness (cIMT) in midlife.

METHODS

A hierarchical agglomerative and k-means clustering analysis based on NP scores (standardized for age, sex, and race) was conducted among 1,203 participants (age 48±5.3 years) from the Bogalusa Heart Study. Regression models assessed the association between cIMT ≥50th percentile and NP profiles, and global cognitive score (GCS) tertiles for sensitivity analysis.

RESULTS

Three NP profiles were identified: Mixed-low performance [16%, n = 192], scores ≥1 SD below the mean on immediate, delayed free recall, recognition verbal memory, and information processing; Average [59%, n = 704]; and Optimal [26%, n = 307] NP performance. Participants with greater cIMT were more likely to have a Mixed-low profile [OR = 3.10, 95% CI (2.13, 4.53), p < 0.001] compared to Optimal. After adjusting for education and cardiovascular (CV) risks, results remained. The association with GCS tertiles was more attenuated [lowest (34%, n = 407) versus highest (33%, n = 403) tertile: adjusted OR = 1.66, 95% CI (1.07, 2.60), p = 0.024].

CONCLUSION

As early as midlife, individuals with higher subclinical atherosclerosis were more likely to be in the Mixed-low profile, underscoring the potential malignancy of CV risk as related to NP test performance, suggesting that classification approaches may aid in identifying those at risk for AD/vascular dementia spectrum illness.

Risk Factors for High Symptom Burden Three Months after Traumatic Brain Injury and Implications for Clinical Trial Design: A Transforming Research and Clinical Knowledge in Traumatic Brain Injury Study

More than 75% of patients presenting to level I trauma centers in the United States with suspicion of TBI sufficient to require a clinical computed tomography scan report injury-related symptoms 3 months later. There are currently no approved treatments, and few clinical trials have evaluated possible treatments. Efficient trials will require subject inclusion and exclusion criteria that balance cost-effective recruitment with enrolling individuals with a higher chance of benefiting from the interventions. Using data from the Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study, we examined the relationship of 3-month symptoms to pre-injury, demographic, and acute characteristics as well as 2-week symptoms and blood-based biomarkers to identify and evaluate factors that may be used for sample enrichment for clinical trials. Many of the risk factors for TBI symptoms reported in the literature were supported, but the effect sizes of each were small or moderate (< 0.5). The only factors with large effect sizes when predicting 3-month symptom burden were TBI-related (i.e., post-concussive) and post-traumatic stress symptom levels at 2 weeks (respective effect sizes 1.13 and 1.34). TBI severity was not significantly associated with 3-month symptom burden (p = 0.37). Using simulated data to evaluate the effect of enrichment, we showed that including only people with high symptom burden at 2 weeks would permit trials to reduce the sample size by half, with minimal increase in screening, as compared with enrolling an unenriched sample. Clinical trials aimed at reducing symptoms after TBI can be efficiently conducted by enriching the included sample with people reporting a high early symptom burden.

Association Between TBI-Related Hearing Impairment and Cognition: A TRACK-TBI Study

OBJECTIVE

To examine the association between hearing impairment and cognitive function after traumatic brain injury (TBI).

SETTING

A total of 18 level I trauma centers throughout the United States in the T ransforming R esearch a nd C linical K nowledge in TBI (TRACK-TBI) study.

PARTICIPANTS

From February 2014 to June 2018, a total of 2697 participants with TBI were enrolled in TRACK-TBI. Key eligibility criteria included external force trauma to the head, presentation to a participating level I trauma center, and receipt of a clinically indicated head computed tomographic (CT) scan within 24 hours of injury. A total of 1267 participants were evaluated in the study, with 216 participants with hearing impairment and 1051 participants without hearing impairment. Those with missing or unknown hearing status or cognitive assessment were excluded from analysis.

DESIGN

Prospective, observational cohort study.

MAIN MEASURES

Hearing impairment at 2 weeks post-TBI was based on self-report. Participants who indicated worse hearing in one or both ears were defined as having hearing impairment, whereas those who denied worse hearing in either ear were defined as not having hearing impairment and served as the reference group. Cognitive outcomes at 6 months post-TBI included executive functioning and processing speed, as measured by the Trail Making Test (TMT) B/A and the Wechsler Adult Intelligence Scale, Fourth Edition, Processing Speed Index subscale (WAIS-IV PSI), respectively.

RESULTS

TBI-related hearing impairment had a small but significantly greater TMT B/A ratio than without TBI-related hearing impairment: mean difference ( B ) = 0.25; 95% CI, 0.07 to 0.43; P = .005. No significant mean differences on WAIS-IV PSI scores were found between participants with and without TBI-related hearing impairment: B = 0.36; 95% CI, -2.07 to 2.60; P = .825.

CONCLUSION

We conclude that TBI-related hearing impairment at 6 months postinjury was significantly associated with worse executive functioning but not cognitive processing speed.

Multimodal deep learning for Alzheimer's disease dementia assessment

Worldwide, there are nearly 10 million new cases of dementia annually, of which Alzheimer's disease (AD) is the most common. New measures are needed to improve the diagnosis of individuals with cognitive impairment due to various etiologies. Here, we report a deep learning framework that accomplishes multiple diagnostic steps in successive fashion to identify persons with normal cognition (NC), mild cognitive impairment (MCI), AD, and non-AD dementias (nADD). We demonstrate a range of models capable of accepting flexible combinations of routinely collected clinical information, including demographics, medical history, neuropsychological testing, neuroimaging, and functional assessments. We then show that these frameworks compare favorably with the diagnostic accuracy of practicing neurologists and neuroradiologists. Lastly, we apply interpretability methods in computer vision to show that disease-specific patterns detected by our models track distinct patterns of degenerative changes throughout the brain and correspond closely with the presence of neuropathological lesions on autopsy. Our work demonstrates methodologies for validating computational predictions with established standards of medical diagnosis.

Longitudinal Changes in Hearing and Visual Impairments and Risk of Dementia in Older Adults in the United States

IMPORTANCE

Hearing and vision problems are individually associated with increased dementia risk, but the impact of having concurrent hearing and vision deficits, ie, dual sensory impairment (DSI), on risk of dementia, including its major subtypes Alzheimer disease (AD) and vascular dementia (VaD), is not well known.

OBJECTIVE

To evaluate whether DSI is associated with incident dementia in older adults.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study from the Cardiovascular Health Study (CHS) was conducted between 1992 and 1999, with as many as 8 years of follow-up. The multicenter, population-based sample was recruited from Medicare eligibility files in 4 US communities with academic medical centers. Of 5888 participants aged 65 years and older in CHS, 3602 underwent cranial magnetic resonance imaging and completed the modified Mini-Mental State Examination in 1992 to 1994 as part of the CHS Cognition Study. A total of 227 participants were excluded due to prevalent dementia, leaving a total of 3375 participants without dementia at study baseline. The study hypothesis was that DSI would be associated with increased risk of dementia compared with no sensory impairment. The association between the duration of DSI with risk of dementia was also evaluated. Data analysis was conducted from November 2019 to February 2020.

EXPOSURES

Hearing and vision impairments were collected via self-report at baseline and as many as 5 follow-up visits.

MAIN OUTCOMES AND MEASURES

All-cause dementia, AD, and VaD, classified by a multidisciplinary committee using standardized criteria.

RESULTS

A total of 2927 participants with information on hearing and vision at all available study visits were included in the analysis (mean [SD] age, 74.6 [4.8] years; 1704 [58.2%] women; 455 [15.5%] African American or Black; 2472 [85.5%] White). Compared with no sensory impairment, DSI was associated with increased risk of all-cause dementia (hazard ratio [HR], 2.60; 95% CI, 1.66-2.06; P < .001), AD (HR, 3.67; 95% CI, 2.04-6.60; P < .001) but not VaD (HR, 2.03; 95% CI, 1.00-4.09; P = .05).

CONCLUSIONS AND RELEVANCE

In this cohort study, DSI was associated with increased risk of dementia, particularly AD. Evaluation of hearing and vision in older adults may help to identify those at high risk of developing dementia.

Effectiveness of Smartphone-Based Community Case Management on the Urgent Referral, Reconsultation, and Hospitalization of Children Aged Under 5 Years in Malawi: Cluster-Randomized, Stepped-Wedge Trial

Background

Integrated community case management (CCM) has led to reductions in child mortality in Malawi resulting from illnesses such as malaria, pneumonia, and diarrhea. However, adherence to CCM guidelines is often poor, potentially leading to inappropriate clinical decisions and poor outcomes. We determined the impact of an e-CCM app on the referral, reconsultation, and hospitalization rates of children presenting to village clinics in Malawi.

Objective

We determined the impact of an electronic version of a smartphone-based CCM (e-CCM) app on the referral, reconsultation, and hospitalization rates of children presenting to village clinics in Malawi.

Methods

We used a stepped-wedge, cluster-randomized trial to compare paper-based CCM (control) with and without the use of an e-CCM app on smartphones from November 2016 to February 2017. A total of 102 village clinics from 2 districts in northern Malawi were assigned to 1 of 6 clusters, which were randomized on the sequencing of the crossover from the control phase to the intervention phase as well as the duration of exposure in each phase. Children aged ≥2 months to <5 years who presented with acute illness were enrolled consecutively by health surveillance assistants. The primary outcome of urgent referrals to higher-level facilities was evaluated by using multilevel mixed effects models. A logistic regression model with the random effects of the cluster and the fixed effects for each step was fitted. The adjustment for potential confounders included baseline factors, such as patient age, sex, and the geographical location of the village clinics. Calendar time was adjusted for in the analysis.

Results

A total of 6965 children were recruited—49.11% (3421/6965) in the control phase and 50.88% (3544/6965) in the intervention phase. After adjusting for calendar time, children in the intervention phase were more likely to be urgently referred to a higher-level health facility than children in the control phase (odds ratio [OR] 2.02, 95% CI 1.27-3.23; P=.003). Overall, children in the intervention arm had lower odds of attending a repeat health surveillance assistant consultation (OR 0.45, 95% CI 0.34-0.59; P<.001) or being admitted to a hospital (OR 0.75, 95% CI 0.62-0.90; P=.002), but after adjusting for time, these differences were not significant (P=.07 for consultation; P=.30 for hospital admission).

Conclusions

The addition of e-CCM decision support by using smartphones led to a greater proportion of children being referred to higher-level facilities, with no apparent increase in hospital admissions or repeat consultations in village clinics. Our findings provide support for the implementation of e-CCM tools in Malawi and other low- and middle-income countries with a need for ongoing assessments of effectiveness and integration with national digital health strategies.

Trial Registration

ClinicalTrials.gov NCT02763345; https://clinicaltrials.gov/ct2/show/NCT02763345

Ophthalmic conditions associated with dementia risk: The Cardiovascular Health Study

INTRODUCTION

Ophthalmic conditions and dementia appear to overlap and may share common pathways, but research has not differentiated dementia subtypes.

METHODS

Diagnoses of cataracts, age-related macular degeneration (AMD), diabetic retinopathy (DR), and glaucoma were based on medical histories and International Classification of Diseases, Ninth Revision (ICD-9) codes for 3375 participants from the Cardiovascular Health Study. Dementia, including Alzheimer's disease (AD) and vascular dementia (VaD), was classified using standardized research criteria.

RESULTS

Cataracts were associated with AD (hazard ratio [HR] = 1.34; 95% confidence interval [CI] = 1.01-1.80) and VaD/mixed dementia (HR = 1.41; 95% CI = 1.02-1.95). AMD was associated with AD only (HR = 1.87; 95% CI = 1.13-3.09), whereas DR was associated with VaD/mixed dementia only (HR = 2.63; 95% CI = 1.10-6.27).

DISCUSSION

Differential associations between specific ophthalmic conditions and dementia subtypes may elucidate pathophysiologic pathways. Lack of association between glaucoma and dementia was most surprising from these analyses.

Correlation between extent of sinus surgery, radiographic disease, and postoperative outcomes

BACKGROUND

The extent of endoscopic sinus surgery (ESS) required for optimal outcomes in chronic rhinosinusitis (CRS) is undefined. We evaluated whether concordance between the extent of surgery and degree of radiographic disease influences postoperative outcomes.

METHODS

247 CRS patients who underwent ESS were retrospectively assigned a concordance score reflecting the similarity between the extent of surgery and degree of radiographic disease. 0 points were assigned when sinusotomy was performed on a diseased sinus, or no sinusotomy was performed on a nondiseased sinus; plus 1 for sinusotomy on a nondiseased sinus; and -1 for a diseased sinus left unopened. The total possible score ranged from minus 10 to plus 10. Patients were divided into 5 subgroups according to variance from complete concordance. SNOT-22 scores and revision rates were compared at 6 and 24 months.

RESULTS

All five subgroups had similar preoperative SNOT-22 scores and improved at 6 months postoperatively. At 6 months postoperatively, the most conservatively operated and most extensively operated subgroups each achieved equivalent improvements in SNOT-22 as the completely concordant subgroup. At 24 months, the most extensively operated subgroup had a 12.5-point smaller improvement in SNOT-22 scores compared to the completely concordant subgroup. Multivariate analysis showed no association between concordance score and revision rate.

CONCLUSIONS

Symptom improvement and revision rates after ESS do not appear to correlate with the degree of concordance between extent of surgery and radiographic disease. More extensive surgery than indicated by CT confers neither greater symptomatic improvement nor long-term detriment.

Dual sensory impairment in older adults and risk of dementia from the GEM Study

INTRODUCTION

Hearing and vision loss are independently associated with dementia, but the impact of dual sensory impairment (DSI) on dementia risk is not well understood.

METHODS

Self-reported measures of hearing and vision were taken from 2051 participants at baseline from the Gingko Evaluation of Memory Study. Dementia status was ascertained using standardized criteria. Cox models were used to estimate risk of dementia associated with number of sensory impairments (none, one, or two).

RESULTS

DSI was significantly associated with higher risk of all-cause dementia (hazard ratio [HR] = 1.86; 95% confidence interval [CI] = 1.25-2.76) and Alzheimer's disease (HR = 2.12; 95% CI = 1.34-3.36). Individually only visual impairment was independently associated with an increased risk of all-cause dementia (HR = 1.32; 95% CI = 1.02-1.71).

DISCUSSION

Older adults with DSI are at a significantly increased risk for dementia. Further studies are needed to evaluate whether treatments can modify this risk.

PPARγ induces growth inhibition and apoptosis through upregulation of insulin-like growth factor-binding protein-3 in gastric cancer cells

Peroxisome proliferator activator receptor-gamma (PPARγ) is a ligand-activated transcriptional factor involved in the carcinogenesis of various cancers. Insulin-like growth factor-binding protein-3 (IGFBP-3) is a tumor suppressor gene that has anti-apoptotic activity. The purpose of this study was to investigate the anticancer mechanism of PPARγ with respect to IGFBP-3. PPARγ was overexpressed in SNU-668 gastric cancer cells using an adenovirus gene transfer system. The cells in which PPARγ was overexpressed exhibited growth inhibition, induction of apoptosis, and a significant increase in IGFBP-3 expression. We investigated the underlying molecular mechanisms of PPARγ in SNU-668 cells using an IGFBP-3 promoter/luciferase reporter system. Luciferase activity was increased up to 15-fold in PPARγ transfected cells, suggesting that PPARγ may directly interact with IGFBP-3 promoter to induce its expression. Deletion analysis of the IGFBP-3 promoter showed that luciferase activity was markedly reduced in cells without putative p53-binding sites (-Δ1755, -Δ1795). This suggests that the critical PPARγ-response region is located within the p53-binding region of the IGFBP-3 promoter. We further demonstrated an increase in PPARγ-induced luciferase activity even in cells treated with siRNA to silence p53 expression. Taken together, these data suggest that PPARγ exhibits its anticancer effect by increasing IGFBP-3 expression, and that IGFBP-3 is a significant tumor suppressor.

Eckols reduce dental pulp inflammation through the ERK1/2 pathway independent of COX-2 inhibition

OBJECTIVES

The aim of this study was to elucidate the role of 6-6 bieckol (EB1) and pholorofucofuroeckol-A (EB5) from brown seaweed marine algae (Eisenia bicyclis) on lipopolysaccharide (LPS)-induced inflammation in human dental pulp cells (HDPCs).

METHODS

The cytotoxicity of EB1 and EB5 was examined by MTT assay on LPS-induced human dental pulp cells. Their role on expression of inflammatory, odontogenic, and osteogenic molecules was determined by Western blot analysis. The dentin mineralization was checked by alkaline phosphatase activity.

RESULTS

The five compounds from E. bicyclis have different structure with non-cytotoxic in HDPCs. EB1 and EB5 showed anti-inflammatory properties and inhibited phosphorylated-extracellular signal-regulated kinase (p-ERK1/2) and phosphorylated-c-jun N-terminal kinases (p-JNK) without any cytotoxicity. In particular, EB1 inhibited cyclooxygenase-2 (COX-2) and p-ERK1/2 signaling, and EB5 inhibited only p-ERK1/2 signaling but not COX-2. Both compounds inhibited nuclear factor kappa-B (NF-κB) translocation. Furthermore, EB1 and EB5 increased dentinogenic and osteogenic molecules, and dentin mineralized via alkaline phosphatase activity (ALP) in LPS-induced HDPCs.

CONCLUSIONS

This study elucidates that EB1 and EB5 have different types of anti-inflammatory property and help in dentin formation. Therefore, these compounds derived from marine algae of E. bicyclis may be used as selective therapeutic strategies for pulpitis and oral diseases.

Alcohol intake and folate antagonism via CYP2E1 and ALDH1: effects on oral carcinogenesis

The interaction of folate and alcohol consumption has been shown to have an antagonistic effect on the risk of oral cancer. Studies have demonstrated that increased intake of folate decreases the risk of oral cancer, while greater alcohol consumption has an opposite effect. However, what is poorly understood is the biological interaction of these two dietary factors in relation to carcinogenesis. We hypothesize that cytochrome P450 2E1 (CYP2E1) and the family of aldehyde dehydrogenase 1 (ALDH1) enzymes may play a causal role in the occurrence of oral cancer. Chronic and high alcohol use has been implicated in the induction of CYP2E1, which oxidizes ethanol to acetaldehyde. Acetaldehyde is a known carcinogen. As the first metabolite of ethanol, it has been shown to interfere with DNA methylation, synthesis and repair, as well as bind to protein and DNA to form stable adducts, which lead to the eventual formation of damaged DNA and cell proliferation. Studies using liver cells have demonstrated that S-adenosyl methionine (SAM), which is a product of folate metabolism, regulates the expression and catalytic activity of CYP2E1. Our first hypothesis is that as increased levels of folate lead to higher concentrations of SAM, SAM antagonizes the expression of CYP2E1, which results in decreased conversion of ethanol into acetaldehyde. Thus, the lower levels of acetaldehyde may lower risk of oral cancer. There are also two enzymes within the ALDH1 family that play an important role both in ethanol metabolism and the folate one-carbon pathway. The first, ALDH1A1, converts acetaldehyde into its non-carcinogenic byproduct, acetate, as part of the second step in the ethanol metabolism pathway. The second, ALDH1L1, also known as FDH, is required for DNA nucleotide biosynthesis, and is upregulated at high concentrations of folate. ALDH1L1 appears to be a chief regulator of cellular metabolism as it is strongly downregulated at certain physiological and pathological conditions, while its upregulation can produce drastic antiproliferative effects. ALDH1 has three known response elements that regulate gene expression (NF-Y, C/EBPβ, and RARα). Our second hypothesis is that folate interacts with one of these response elements to upregulate ALDH1A1 and ALDH1L1 expression in order to decrease acetaldehyde concentrations and promote DNA stability, thereby decreasing cancer susceptibility. Conducting future metabolic and biochemical human studies in order to understand this biological mechanism will serve to support evidence from epidemiologic studies, and ultimately promote the intake of folate to at-risk populations.

Amphiphilic triblock copolymer poly(p-dioxanone-co-L-lactide)-block-poly(ethylene glycol), enhancement of gene expression and inhibition of lung metastasis by aerosol delivery

We describe the development of an aerosol system for topical gene delivery to the lungs of C57BL/6 mice. This system is based on the combination of the commercial cationic lipid Lipofectin with a novel amphiphilic triblock copolymer, poly(p-dioxanone-co-L-lactide)-block-poly(ethylene glycol) (PPDO/PLLA-b-PEG, and abbreviated in the text as polymeric micelles). After optimizing conditions for DNA delivery to the lungs of mice using the combination of polymeric micelles with Lipofectin and LacZ DNA, we used the Lipofectin/polymeric micelle system to deliver the tumor suppressor gene PTEN to the lungs of C57BL/6 mice bearing the B16-F10 melanoma. Lipofectin/PTEN/polymeric micelles significantly improved gene expression of PTEN in the lungs of mice with no evidence of cell toxicity or acute inflammation. Importantly, lung metastasis, as measured by lung weight, was significantly reduced (P<0.001), as were total tumor foci in the lungs (P<0.001) and size of individual tumor nodules in animals treated with Lipofectin/PTEN/polymeric micelles compared with control animals. Survival time was also extended. These results suggest that the Lipofectin/polymeric micelle system is appropriate for enhancing gene delivery in vivo and that it can be applied as a non-invasive gene therapy for lung cancer.

Effects of cold-water immersion on VEGF mRNA and protein expression in heart and skeletal muscles of rats

AIM

The effects of cold exposure on gene and protein expression of vascular endothelial growth factor (VEGF), in heart and skeletal muscles, were studied in male adult Wistar rats.

METHODS

Cold immersion was accomplished by submerging the rats in shoulder-deep water maintained at approximately 18 degrees C, either acutely (1 h) or chronically (1 h day(-1), 5 days week(-1) for 20 weeks). The expressions of VEGF mRNA and protein in heart, gastrocnemius, and soleus muscles were examined by Northern and Western blotting and competitive-polymerase chain reaction techniques.

RESULTS

The expressions of VEGF mRNA and protein were markedly increased in cardiac muscle of the cold-immersed group, particularly in the 1-hour exposure group, whereas VEGF mRNA and protein in gastrocnemius were decreased significantly after an acute exposure. Although the protein level in gastrocnemius remained low in the chronically exposed group, the expression of mRNA of VEGF(165) with chronic exposure in this group returned to the control level and that of VEGF(206) was 15% greater than that in controls. The expression of mRNA for VEGF(165) in soleus was also lowered by acute cold exposure, although that for VEGF(206) was stable. However, VEGF protein was increased by 50%. After 20 weeks, all of these parameters were increased over the levels found in the controls.

CONCLUSION

These results suggest that the VEGF gene may be a major regulatory factor in cardiac and skeletal muscle adaptation to the cold environment stimulating angiogenesis and thermogenesis.

Incidence of Haemophilus influenzae type b and other invasive diseases in South Korean children

To determine incidence of invasive Haemophilus influenzae type b (Hib) disease in a defined population of Jeonbuk Province, Korea, children <5 years were evaluated in prospective, population-based surveillance of invasive bacterial diseases using standardized methods for patient referral, clinical evaluation and laboratory testing (optimized culture, latex agglutination, polymerase chain reaction). Vaccine utilization was assessed with vaccination histories of patients in surveillance, monthly data on Hib vaccine distribution and a coverage survey of clinic patients in study population. From September 1999 to December 2001, 2176 children were evaluated for possible meningitis, 1541 had no cerebrospinal fluid (CSF) findings of meningitis, 605 had CSF abnormalities (suspected bacterial meningitis) but no pathogen identified; six patients had probable Hib meningitis and eight had confirmed Hib meningitis. The annual suspected bacterial meningitis incidence was 258.4/100,000 <5 years and the probable/confirmed Hib meningitis incidence was 6.0/100,000 <5 years. Pneumococcal meningitis incidence was 2.1/100,000 <5 years and Group B streptococcal meningitis incidence was 0.17/1000 live births. A total of 69,589 Hib vaccine doses were distributed during the study. Hib vaccine coverage was negligible initially but increased to 16% (complete Hib immunization) and 27% (partial immunization) in final months of study. Suspected bacterial meningitis incidence was high but proven invasive Hib meningitis incidence was low. Hib was leading cause of bacterial meningitis yet bacterial pathogens were identified in only 4% of abnormal CSF. These findings may reflect truly low incidence, presumptive antibiotic treatment, partial Hib immunization, or incomplete clinical evaluations. Given the apparent Hib meningitis burden in Jeonbuk Province, additional studies to describe other invasive Hib syndromes, Hib-associated mortality and disability, and economic impact of Hib disease will be useful to guide public health decisions regarding routine Hib vaccine introduction.

Expression of the insulin-like growth factors (IGFs) and the IGF-binding proteins (IGFBPs) in human gastric cancer cells

Insulin-like growth factor (IGF)-I and -II are potent mitogens and postulated to exert autocrine, and paracrine effects on growth regulation in human gastric cancer. Their mitogenic effects are tightly regulated by the IGF binding proteins (IGFBPs). In this study, we evaluated the mRNA expression of IGF-I, IGF-II and the IGFBPs in a panel of human gastric cancer cell lines, and normal and tumour tissue specimens from patients with gastric cancer by reverse transcriptase-polymerase chain reaction (RT-PCR) and competitive PCR. Conditioned media (CM) of the gastric cancer cell lines were studied for the secretion of the IGFBPs by western ligand blot (WLB) and western immunoblot (WIB). IGF-I and IGF-II were expressed in all of the gastric cancer cell lines, and the normal and tumour tissue specimens. Overexpression of the IGFs, in particular, IGF-II, was observed in the tumour tissues. The expression pattern of IGFBPs was heterogeneous among the gastric cancer cell lines. IGFBP-2 was expressed in all of the gastric cancer cell lines, whereas IGFBP-1 was not detected in any cell lines. IGFBP-4 was expressed in the most of cell lines. IGFBP-3, IGFBP-5 and IGFBP-6 were expressed in approximately 50% of cell lines. In addition, exogenous IGF-I and IGF-II stimulated the proliferation of gastric cancer cells, suggesting the existence of a functional IGF system in gastric cancer. Taken together, our data-suggest that the IGF-IGFBP system may play an important role in the initiation, progression and metastasis of gastric cancer. Further studies are needed to understand the exact role of IGFs and IGFBPs in gastric neoplasia.

Suppression of tumorigenicity and metastasis in B16F10 cells by PTEN/MMAC1/TEP1 gene

PTEN/MMAC1/TEP1 (PTEN) is a tumor suppressor gene that is mutated in a variety of advanced and metastatic cancers, strongly suggests that PTEN alteration is possibly involved in the tumor progression and formation of metastases. However, the roles of PTEN in tumor growth and metastasis and its functional mechanisms are not fully understood. We evaluated the tumor suppressor function of PTEN gene on tumor growth and metastasis in vitro and in vivo. Our results of in vitro soft agar assay and in vivo PTEN-expressing tumor cell growth showed that PTEN inhibited the tumorigenicity of B16F10 melanoma cells. Anti-metastatic function of PTEN was also revealed by experimental pulmonary metastatic animal model. For the further insight into the mechanisms underlying the PTEN-mediated inhibition of tumor metastasis, we have examined the role of PTEN on the secretion of matrix metalloproteinases (MMPs), insulin-like growth factors (IGFs) and the expression of secretory and cellular vascular endothelial growth factor (VEGF) proteins that have been described to contribute to the metastasis of tumor. PTEN significantly lowered MMPs and IGFs secretion and also expression of secretory and cellular VEGF proteins. These results suggest that PTEN tumor suppressor protein inhibits tumorigenicity and metastasis through regulation of MMP, IGFs, and VEGF expression.

Bony abnormalities of the paranasal sinuses in patients with Wegener's granulomatosis

Wegener's granulomatosis is a systemic vasculitis that can affect any organ system, but primarily involves the upper and lower respiratory tracts and the kidneys. Chronic sinusitis is a well-known clinical feature of the disease. Mucosal abnormalities of the nose and paranasal sinuses have been well-characterized and range from granulomatous lesions to diffuse mucosal thickening. In contrast, abnormalities of the underlying bone of the paranasal sinuses in this disease have not been well-described, and reports have been limited. To characterize bony abnormalities of the nose and paranasal sinuses in patients with Wegener's granulomatosis, we performed a retrospective review of all patients with Wegener's granulomatosis who underwent a sinus CT scan at our institution between 1989 and 1999. Nine patients were identified. A total of 22 distinct bony abnormalities were identified in 5 patients. Specific bony findings included bony erosion and destruction of the septum and turbinates; erosion of the ethmoid sinuses; neo-osteogenesis of the maxillary, frontal, and sphenoid sinuses; and complete bony obliteration of the maxillary, frontal, and sphenoid sinuses. Although these findings are suggestive of Wegener's granulomatosis, they are not pathognomonic. Bony changes on sinus CT scan may provide radiologic evidence of underlying Wegener's granulomatosis when clinical suspicion is high.

Medical therapy of acute and chronic frontal rhinosinusitis

Despite innovations in surgical treatment of frontal sinus disease, medical therapy continues to be important. Preoperative, perioperative, and postoperative considerations are discussed. Diagnostic criteria, microbiology, and complications associated with frontal rhinosinusitis are also reviewed.

The five year experience with endoscopic trans-septal frontal sinusotomy

Endoscopic trans-septal frontal sinusotomy (TSFS) represents a unique surgical approach to the floor of the frontal sinus. Although the final result can have similarities to the modified Lothrop procedure in that the intersinus septum may be drilled out, endoscopic TSFS represents a novel approach that can be valuable in patients with certain anatomic configurations. Endoscopic TSFS represents an alternate approach to the frontal sinus that may be used by the experienced endoscopist to augment treatment of refractory frontal sinus disease. This procedure is best considered for patients with favorable anatomy who have significant frontal sinus disease and cannot be managed adequately through an endoscopic frontal sinusotomy.

Fc gamma receptors differ in their structural requirements for interaction with the tyrosine kinase Syk in the initial steps of signaling for phagocytosis

Receptors for the constant region of IgG, Fc gamma receptors, are expressed on the surface of hematopoietic cells, where they mediate signaling events, such as phagocytosis, essential for host defense. Fc gamma receptors also play a role in the pathophysiology of autoimmune diseases. We have demonstrated that members of each of the three classes of human Fc gamma receptors, Fc gamma RI, Fc gamma RII, and Fc gamma RIII, mediate phagocytosis, but that important differences exist in their requirements for phagocytic signaling. For example, the Fc gamma receptors Fc gamma RI and Fc gamma RIIIA induce signaling largely by association with a gamma subunit containing a conserved cytoplasmic motif (ITAM) whose tyrosines are phosphorylated following receptor stimulation. Fc gamma RIIA contains a similar motif in its own cytoplasmic domain and does not require the gamma chain for phagocytic signaling. The tyrosine kinase Syk associates with the cytoplasmic domain of both the Fc gamma receptor gamma chain and Fc gamma RIIA and is required for phagocytosis by both Fc gamma receptor systems. To elucidate the differences in phagocytic signaling by the gamma chain and Fc gamma RIIA, we investigated the requirements for Fc gamma receptor/Syk co-immunoprecipitation, tyrosine phosphorylation, and phagocytosis. Both Fc gamma RIIA and the human gamma chain contain a tyrosine seven amino acids upstream of the ITAM motif. We observed that the upstream tyrosine plays a role in Fc gamma RIIA phagocytic signaling but is not involved in phagocytic signaling by the human gamma chain. Our data also indicate that the two ITAM tyrosines of the human gamma chain and Fc gamma RIIA do not contribute equally to Fc gamma receptor association with Syk kinase and phagocytic signaling. The data indicate that the carboxy-terminal tyrosine of the receptor cytoplasmic domain is especially important both for the interaction with Syk kinase and for phagocytosis. Elucidating such differences in gamma chain and Fc gamma RIIA signaling may be valuable in designing strategies for therapeutic intervention in hematopoietic and immunological disorders.

Aerosolized Syk antisense suppresses Syk expression, mediator release from macrophages, and pulmonary inflammation

Syk protein tyrosine kinase (PTK) is involved in signaling in leukocytes. In macrophages, Fcgamma-receptor cross-linking induces Syk PTK phosphorylation and activation, resulting in Syk-dependent events required for phagocytosis and mediator release. We hypothesized that Syk antisense oligodeoxynucleotides (ASO) delivered by aerosol to rat lungs in vivo would depress Syk PTK expression, mediator release from alveolar macrophages, and Syk-dependent pulmonary inflammation. RT-PCR and RT-in situ PCR demonstrated that aerosolized Syk ASO administration reduced Syk mRNA expression from alveolar macrophages compared with cells isolated from sham-treated rats. Western blot analysis confirmed that Syk PTK expression was reduced after Syk ASO treatment. Compared with sham-treated rats (scrambled oligodeoxynucleotide), Syk ASO treatment suppressed Fcgamma-receptor-mediated nitric oxide (86.0 +/- 8.3%) and TNF (73.1 +/- 3.1%) production by alveolar macrophages stimulated with IgG-anti-IgG complexes. In contrast, Fcgamma-receptor-induced IL-1beta release was unaffected by Syk ASO treatment. Additionally, Syk ASO suppressed Ag-induced pulmonary inflammation, suggesting that Syk ASO may prove useful as an anti-inflammatory therapy in disorders such as asthma.

Effectiveness of preoperative transarterial chemoembolization in presumed inoperable hepatoblastoma

PURPOSE

To evaluate the effectiveness and therapeutic role of preoperative transarterial chemoembolization (TACE) of hepatoblastoma.

MATERIALS AND METHODS

Four patients (one boy, three girls) with unresectable hepatoblastoma were treated twice with preoperative TACE in an effort to improve the surgical and clinical outcome. The patients ranged in age from 8 to 27 months (mean, 15 months). The first TACE was performed superselectively in tumor feeding arteries. The second TACE was performed 3 weeks later. Surgical hepatic resection was performed 1 month after the second TACE. Contrast-enhanced computed tomography (CT) was used to evaluate changes in size, volume, internal texture, and margin of the masses. The toxicity of the chemotherapeutic drugs was evaluated by blood chemistry analysis (AST/ALT, alpha-FP) performed before and after TACE, and after surgery.

RESULTS

TACE allowed subsequent surgical resection in all four patients, who remained disease free 16-52 months after operation. There were no major problems related to TACE. There was no chemotherapeutic agent toxicity from TACE. The average largest diameters and volumes of the tumors decreased by 31% (8.3 to 5.6 cm) and 69% (317 to 93 cm2), respectively.

CONCLUSION

TACE provided subsequent successful surgical resection and good long-term results in all four patients. The hepatoblastomas were initially considered inoperable because of extensive hepatic involvement and indistinct margins.

Applications of in situ hybridization techniques in the diagnosis of chronic sinusitis

The clinical significance of positive bacterial cultures in chronic sinusitis is often difficult to assess. Contaminants from surface colonization of the sinus mucosa may be difficult to distinguish from true intramucosal or bone involvement. Furthermore, tissue Gram stains are frequently unable to demonstrate the presence of bacteria in tissue despite endoscopic evidence of active sinusitis. In situ hybridization (ISH) techniques using bacterial rRNA probes were applied to evaluate the presence of intramucosal and intraosseous bacteria in chronic sinusitis surgical specimens. A total of 22 specimens of chronically inflamed human ethmoid bone were evaluated by ISH and by Gram stain. In three specimens, ISH identified bacterial rRNA within sinus mucosa and mucin. Notably, in these three ISH-positive specimens, Gram stain was negative in two. No specimen showed evidence of bacterial rRNA within bone. These preliminary results suggest that in situ hybridization may be a useful adjunct to current methods of detecting microorganisms within chronically infected sinus tissue.

Endoscopic trans-septal frontal sinusotomy: the rationale and results of an alternative technique

Endoscopic transseptal frontal sinusotomy (TSFS) represents an alternate approach to surgical treatment of chronic frontal sinus disease that is refractory to traditional modes of medical and surgical therapy. We retrospectively reviewed our experience with endoscopic TSFS from 1995-1997. Twenty-one procedures were performed through a transseptal approach. One patient was excluded for failure to follow-up, for a total of 20 procedures. Patients were followed with serial endoscopic examinations and a telephone questionnaire with a mean follow-up of 12 months (Range 1-24 months) and 16 months (range 5-31), respectively. The primary indication for surgery was frontal recess stenosis after previous endoscopic frontal sinusotomy in 17/20 (85%). Three patients were considered poor candidates for a primary endoscopic frontal sinusotomy. Patency was maintained in all patients during the follow-up period. A diameter of greater than 3 mm was confirmed by passage of a curved suction in 19/20 (95%). Of the 19 patients that were evaluated via a telephone questionnaire, 17 patients (89.5%) reported some degree of improvement in their nasal/sinus symptoms, and 12/18 patients (67%) felt the frequency of medication requirements was less than that before undergoing endoscopic TSFS. We conclude that endoscopic TSFS represents an alternate approach to the frontal sinus that may be used by the experienced endoscopist, to augment treatment of refractory frontal sinus disease. This procedure seems especially suited for revision surgery in those patients with acquired frontal sinus stenosis. In revision operations with distorted anatomical landmarks, localization of the frontal sinus may be improved with the aid of 3-dimensional computer assisted localization systems. Unlike traditional frontal sinus obliteration, endoscopic TSFS does not preclude radiographic assessment postoperatively, and allows for endoscopic evaluation of the frontal sinus in the office setting.

Endoscopic septoplasty: indications, technique, and results

Endoscopic septoplasty is an attractive alternative to traditional "headlight" approaches to septoplasty. The primary advantage of the technique is the ability to reduce morbidity and postoperative swelling in isolated septal deviations by limiting the dissection to the area of the deviation. This ability to markedly reduce the extent of subperichondrial dissection is particularly valuable in patients who have undergone prior septal cartilage resection. Other advantages include improved visualization, particularly in posterior septal deformities; improved surgical transition between septoplasty and sinus surgery; and its use as an effective teaching tool. We present our experience with endoscopic septoplasty in a series of 111 patients. Surgical indications, technique, and complications are discussed.

Correction of the twisted nose deformity: a surgical algorithm using the external rhinoplasty approach

Successful correction of the twisted nose is challenging due to the complex nature of the underlying anatomic deformity. Although the literature has in general supported endonasal rhinoplasty techniques for the twisted nose, we propose a surgical algorithm using the external rhinoplasty approach. The algorithm offer a stepwise, structured method that is adaptable to individual variations in anatomic deformity. The advantages and relative disadvantages of the external rhinoplasty approach are discussed, and a clinical experience of 30 patients is reviewed. Application of the external rhinoplasty algorithm in correction of the twisted nose can yield consistently satisfactory functional and aesthetic results.

Lipoid meningitis due to aseptic necrosis of a free fat graft placed during neurotologic surgery

We present two unusual cases of aseptic postoperative lipoid meningitis resulting from necrosis of a free fat graft placed into a skull base craniotomy defect. Two patients underwent translabyrinthine resection of acoustic neuroma and received abdominal fat grafts to ablate the surgical defect. Both patients presented postoperatively with persistent cerebrospinal fluid (CSF) wound leak and severe headache. Computed tomography demonstrated hydrocephalus and widely dispersed intracranial fat droplets throughout the CSF circulation. Both patients ultimately required CSF diversion for management of persistent communicating hydrocephalus. The clinical and radiographic correlates of lipocephalus and lipoid meningitis are presented, and a review of free fat graft physiology is discussed.

Attitudes, Knowledge, and Practices of Otolaryngologists Treating Patients Infected with HIV

The AIDS epidemic has become one of the most important public health problems of this century. As the prevalence of HIV infection continues to rise, health care practitioners in all geographic regions can expect greater clinical exposure to patients infected with HIV. We conducted an anonymous survey of all practicing otolaryngologists in Ohio and California to investigate regional differences in attitudes, knowledge, and practices regarding the care of patients infected with HIV. We also examined the data with respect to year of completion of residency training to identify differences in attitudes or practices among otolaryngologists who trained in the era of AIDS (post-1982 graduates) in comparison with their predecessors (pre-1982 graduates). In comparison with Ohio otolaryngologists, California otolaryngologists reported more frequent clinical encounters with HIV-infected patients and displayed significantly better knowledge regarding the otolaryngologic aspects of HIV infection. Californians were more likely to support the right of an HIV-infected physician to maintain an unrestricted practice and would be less likely to disclose their HIV status to their patients and hospital if they were to become infected with HIV. Post-1982 graduates had more frequent encounters with HIV-infected patients than did pre-1982 graduates and demonstrated a better fund of knowledge. Although Californians were more likely than Ohioans to routinely double glove in surgery, the overall double gloving rate was low at 21%. Californians were no more likely than Ohioans to routinely use protective eyewear, water-impervious gowns, or indirect instrument-passing techniques in surgery. No differences were observed in prevalence of protective surgical precautions between pre-1982 and post-1982 graduates. The results of the survey indicate a need for broader acceptance and use of “universal” surgical precautions among otolaryngologists.

Attitudes, knowledge, and practices of otolaryngologists treating patients infected with HIV

The AIDS epidemic has become one of the most important public health problems of this century. As the prevalence of HIV infection continues to rise, health care practitioners in all geographic regions can expect greater clinical exposure to patients infected with HIV. We conducted an anonymous survey of all practicing otolaryngologists in Ohio and California to investigate regional differences in attitudes, knowledge, and practices regarding the care of patients infected with HIV. We also examined the data with respect to year of completion of residency training to identify differences in attitudes or practices among otolaryngologists who trained in the era of AIDS (post-1982 graduates) in comparison with their predecessors (pre-1982 graduates). In comparison with Ohio otolaryngologists, California otolaryngologists reported more frequent clinical encounters with HIV-infected patients and displayed significantly better knowledge regarding the otolaryngologic aspects of HIV infection. Californians were more likely to support the right of an HIV-infected physician to maintain an unrestricted practice and would be less likely to disclose their HIV status to their patients and hospital if they were to become infected with HIV. Post-1982 graduates had more frequent encounters with HIV-infected patients than did pre-1982 graduates and demonstrated a better fund of knowledge. Although Californians were more likely than Ohioans to routinely double glove in surgery, the overall double gloving rate was low at 21%. Californians were no more likely than Ohioans to routinely use protective eyewear, water-impervious gowns, or indirect instrument-passing techniques in surgery. No differences were observed in prevalence of protective surgical precautions between pre-1982 and post-1982 graduates.(ABSTRACT TRUNCATED AT 250 WORDS)

Enlargement of the cochlear aqueduct: fact or fiction?

Enlargement of the cochlear aqueduct (CA) is often mentioned in the otologic literature, usually in its purported association with sensory hearing loss, stapes gusher, and transotic cerebrospinal fluid leak. In CT scans of 100 ears, the diameter of the CA medial aperture was found to be highly variable, ranging from 0 to 11 mm, with a mean of 4.5 mm. In contrast, the otic capsule segment was very narrow in every case. It could be visualized in only 56% of cases, none of which exceeded 2 mm in diameter. Several published reports of supposed CA enlargement presented images of a dilated medial aperture that was well within the range of normal variability according to the present study. In a thorough review of the literature on radiology of the CA, we were unable to find a single published image that convincingly demonstrated enlargement of the otic capsule portion. As radiographic CA enlargement has not been convincingly reported to date, it appears to be an exceedingly rare or perhaps even nonexistent malformation. It is important to recognize than even a radiographically normal CA may be hyperpatent. It is theoretically possible for increased fluid flow to result from either deficiencies in intraluminal membrane baffles or subtle canal enlargement beneath the resolution limits of CT scanning. However, as fluid flow through a tube is regulated by its narrowest point, it is extremely improbable that stapes gusher, transotic CSF leak, and vigorous perilymphatic fistula are generated by the CA when CT scans show any portion of it to be very narrow. A substantial body of evidence points to a deficient partition between the internal auditory canal and inner ear as causative in such cases. We propose that the criteria for the diagnosis of CA enlargement on high-resolution CT scan be a diameter exceeding 2 mm throughout its course from the posterior fossa to the vestibule.

PPD-specific IgG and IgG subclasses in the sera of pulmonary tuberculosis patients

This study was performed to characterize the humoral immune responses with isotype profiles in Mycobacterium tuberculosis infection. PPD-Specific IgG and IgG subclasses were measured using ELISA in 212 patients with pulmonary tuberculosis. The values of PPD-specific IgG were significantly higher in pulmonary tuberculosis patients than those in the control group, and were correlated to the severity of illness (P < 0.01). The specificity and sensitivity of ELISA for IgG antibodies were 1.0 and 0.81, respectively as determined in 212 sera from tuberculosis patients and 44 from healthy controls. The positive predictive value was 1.0 (171/171), while negative predictive value was 0.52 (44/85). The values of PPD-specific IgG were significantly decreased after 2-4 months of treatment. Among the moderately and far advanced pulmonary tuberculosis patients, the values of PPD-specific IgG were significantly decreased in responders after 6 months of treatment. However, PPD-specific IgG in nonresponders was increased (P < 0.01). PPD-specific IgG subclass responses were evident to all four IgG subclasses. No changes of isotype response according to the severity of the disease were observed.