Optical diagnostics in the oral cavity: an overview

As the emphasis shifts from damage mitigation to disease prevention or reversal of early disease in the oral cavity, the need for sensitive and accurate detection and diagnostic tools become more important. Many novel and emergent optical diagnostic modalities for the oral cavity are becoming available to clinicians with a variety of desirable attributes including: (i) non-invasiveness, (ii) absence of ionizing radiation, (iii) patient-friendliness, (iv) real-time information (v) repeatability, and (vi) high-resolution surface and subsurface images. In this article, the principles behind optical diagnostic approaches, their feasibility and applicability for imaging soft and hard tissues, and their potential usefulness as a tool in the diagnosis of oral mucosal lesions, dental pathologies, and other dental applications will be reviewed. The clinical applications of light-based imaging technologies in the oral cavity and of their derivative devices will be discussed to provide the reader with a comprehensive understanding of emergent diagnostic modalities.

Reliability and intraoperative validity of preoperative assessment of standardized plain radiographs in predicting bone loss at revision hip surgery

BACKGROUND

The most challenging aspect of revision hip surgery is the management of bone loss. A reliable and valid measure of bone loss is important since it will aid in future studies of hip revisions and in preoperative planning. We developed a measure of femoral and acetabular bone loss associated with failed total hip arthroplasty. The purpose of the present study was to measure the reliability and the intraoperative validity of this measure and to determine how it may be useful in preoperative planning.

METHODS

From July 1997 to December 1998, forty-five consecutive patients with a failed hip prosthesis in need of revision surgery were prospectively followed. Three general orthopaedic surgeons were taught the radiographic classification system, and two of them classified standardized preoperative anteroposterior and lateral hip radiographs with use of the system. Interobserver testing was carried out in a blinded fashion. These results were then compared with the intraoperative findings of the third surgeon, who was blinded to the preoperative ratings. Kappa statistics (unweighted and weighted) were used to assess correlation. Interobserver reliability was assessed by examining the agreement between the two preoperative raters. Prognostic validity was assessed by examining the agreement between the assessment by either Rater 1 or Rater 2 and the intraoperative assessment (reference standard).

RESULTS

With regard to the assessments of both the femur and the acetabulum, there was significant agreement (p < 0.0001) between the preoperative raters (reliability), with weighted kappa values of >0.75. There was also significant agreement (p < 0.0001) between each rater's assessment and the intraoperative assessment (validity) of both the femur and the acetabulum, with weighted kappa values of >0.75.

CONCLUSIONS

With use of the newly developed classification system, preoperative radiographs are reliable and valid for assessment of the severity of bone loss that will be found intraoperatively.

Development, test reliability and validation of a classification for revision hip arthroplasty

The objective of the study was to develop a valid and reliable classification system for failed hip arthroplasties. The study uses research principals derived from multi-attribute utility theory and consensus group techniques. The development of the severity measure was done in two phases. Phase I of the study included: (a) questionnaire development, (b) submission of the questionnaire to the respondents, (c) data synthesis of the responses and item reduction, and (d) classification development and inter-observer reliability testing. Phase II included: (a) resubmission of the instrument to the respondents for suggestions/feedback, (b) instrument revision by the co-investigators based on the respondents' second feedback, and (c) inter-observer reliability testing and intraoperative validity testing of the instrument. The questionnaires sought to capture expert opinion as to what clinical determinants obtained preoperatively (during patient interview, physical exam and review of plain radiographs - AP pelvis and hip lateral) that would in their clinical experience reveal intraoperative severity. There was an 80% (16/20) response rate from the outside experts invited to participate in the study. Based on item reduction and test retest analysis, a five-grade radiographic classification for the acetabulum as well as the femur was developed. This system was then reviewed by 13 of the initial outside experts (16, 80%) who participated in the first round. Inter-rater reliability testing of the final format of the classification revealed a weighted kappa statistic value of 0.88 between the two-blinded raters (inter-rater reliability) and 0.87 between the blinded raters and the reference standard (intraoperative validity). We conclude that the study developed a reliable and valid radiographic classification system for failed hip arthroplasty.

Facial attractiveness and the aged

This study examined the relationship between dentofacial appearance and judgments of facial attractiveness in a sample of 60 subjects between ages 65 and 75. Subjects completed questionnaires regarding their current dental appearance and level of satisfaction with their facial attractiveness. Subjects then viewed and ranked four sets of five photographs that had been digitally manipulated to simulate common dental defects. Regardless of background facial attractiveness or gender of stimulus photographs, a specific ranking order for dental defects emerged with rank-order correlations in the 90% range. Findings suggest that dental appearance affects judgments of facial attractiveness regardless of gender or background facial attractiveness.

Long-term functional status and quality of life after lower extremity revascularization

OBJECTIVE

The objective of this study was to assess the longer term (up to 7 years) functional status and quality of life outcomes from lower extremity revascularization.

METHODS

This study was designed as a cross-sectional telephone survey and chart review at the University of Minnesota Hospital. The subjects were patients who underwent their first lower extremity revascularization procedure or a primary amputation for vascular disease between January 1, 1989, and January 31, 1995, who had granted consent or had died. The main outcome measures were ability to walk, SF-36 physical function, SF-12, subsequent amputation, and death.

RESULTS

The medical records for all 329 subjects were reviewed after the qualifying procedures for details of the primary procedure (62.6% arterial bypass graft, 36.8% angioplasty, 0.6% atherectomy), comorbidities (64% diabetics), severity of disease, and other vascular risk factors. All 166 patients who were living were surveyed by telephone between June and August 1996. At 7 years after the qualifying procedure, 73% of the patients who were alive still had the qualifying limb, although 63% of the patients had died. Overall, at the time of the follow-up examination (1 to 7.5 years after the qualifying procedure), 65% of the patients who were living were able to walk independently and 43% had little or no limitation in walking several blocks. In a multiple regression model, patients with diabetes and patients who were older were less likely to be able to walk at follow-up examination and had a worse functional status on the SF-36 and a lower physical health on the SF-12. Number of years since the procedure was not a predictor in any of the analyses.

CONCLUSION

Although the long-term mortality rate is high in the population that undergoes lower limb revascularization, the survivors are likely to retain their limb over time and have good functional status.

The effects of clinical pathways for renal transplant on patient outcomes and length of stay

OBJECTIVES

Clinical pathways have been implemented nationwide but little is understood about their effects on efficiency of care and patient outcomes. The present study examined the effects of both development and implementation of two renal transplant pathways.

METHODS

Cohorts of patients at a university hospital were compared before, during, and after the development and implementation of two renal transplant clinical pathways: isolated renal transplant from cadaveric donors (n = 170) or from living donors (n = 178). Clinical pathways for cadaveric and living related donor renal transplants were developed and implemented. Hospital length of stay and complications and infections after renal transplant were determined.

RESULTS

Mean length of hospital stay decreased after development and implementation of the cadaveric donor pathway (11.8 days after implementation versus 17.5 days before development). Cadaveric kidney recipients also had statistically fewer complications and infections after both guideline development and guideline implementation (57.1% before, 24.5% during, 18.5% after), but the greatest effect occurred during development. All of these findings persisted after control for demographic and comorbid factors. There were no changes in hospital stay, complications, or infections in the patients who received kidneys from living donors.

CONCLUSIONS

The development and use of a clinical pathway for cadaveric donor renal transplant patients was associated with a significant decline in length of stay, complications, and infections, but much of the effect was seen during development rather than during implementation, and a closely related pathway for living related donor patients had no effect. Further understanding of what factors predict an effective pathway and what elements (ie, development or implementation) have an effect should be undertaken.

The effect of HMO status on the outcomes of home-care after hospitalization in a Medicare population

OBJECTIVE

The literature suggests that Medicare health maintenance organization (HMO) patients may have poorer outcomes with formal home-health care than do fee-for-service (FFS) patients, but it is unclear whether this is related to case-mix or quality. Our objective was to compare the home-health care outcomes for HMO and FFS Medicare patients after hospitalization for stroke, COPD, CHF, hip replacement, or hip fracture with fixation or replacement while controlling for site of discharge and other patient characteristics.

DESIGN

Patients were identified before hospital discharge with data collected at that time and then prospectively for 1 year.

SETTING

Nineteen acute general hospitals in Minneapolis/St. Paul, Minnesota.

PATIENTS

All Medicare patients in the above hospitals identified predischarge with stroke, COPD, CHF, hip replacement, or hip fracture with fixation or replacement.

MEASURES

OUTCOME

weighted ADL scale and hospital readmission. Independent factors: site of discharge, HMO status, comorbidity, severity, and demographic factors.

RESULTS

A total of 970 subjects were studied, 211 of whom were discharged to home-care. HMO patients were more likely to be discharged to a nursing home than to home-care after controlling for other factors (OR = 1.7; P = .015). After controlling for site of discharge and patient characteristics through either propensity scores or regression analysis, there was no statistically significant difference in ADL function at 6 weeks or at 6 months between HMO and FFS patients. Nor was there was a statistically significant difference in hospital readmission rates at 6 weeks and 6 months between HMO and FFS home-care patients.

CONCLUSIONS

The outcomes of Medicare HMO patients discharged to home-care are not worse than those of FFS patients.

Development and testing of a process measure of nursing home quality of care

OBJECTIVE

To develop and test quality of care process measures for three medical conditions of nursing home patients: fever, shortness of breath, and chest pain.

DESIGN

Flowsheets designed to capture the critical elements of care for the above conditions were developed by an expert panel. Nursing home residents charts were reviewed retrospectively using the flow sheets. The reviews were translated into clinical scenarios, and the quality of care the scenarios represented was rated by an expert panel.

SETTING

All nursing homes in Hennepin County, MN, that care for Medicaid patients.

PATIENTS

A random sample of 1405 Medicaid nursing home residents from 1984 and 1988.

MEASURES

Measures of quality of physician assessment and intervention, quality of nurse assessment and intervention, and global quality were developed and the intra- and interrater reliability were tested. The measures' validity was assessed by their ability to predict resident death.

RESULTS

Intrarater reliability was measured as the correlation of the ratings of blinded duplicates. The correlation for the global scale and the four subscales ranged from .74 to .88 (P < .001 for all). Interrater reliability was tested by examining what percentage of the quality ratings were within one unit (1-5 scale) for all three raters. All three raters were within one unit for more than 72% scenarios for all scales. The subscale of quality of physician assessment was able to predict resident death when the worst episode of care (OR = .47, 95% CI(.31-.74)) or the mean episode of care (OR .54, 95% CI(.30-.99)) was used. None of the other subscales or the global measure predicted death.

CONCLUSIONS

Through the use of an expert panel, measures of nursing home quality of care were developed for shortness of breath, fever, and chest pain. These measures have reasonable reliability and significant face validity. Their validity is supported further by the ability of one of the measures to predict resident death.

Cystic fibrosis heterozygote screening in 5,161 pregnant women

A screening program for cystic fibrosis (CF) heterozygotes was conducted in a large HMO prenatal population, to evaluate the level of interest among eligible patients, the effectiveness of prescreening education, attitudes toward the screening process, psychological effects, and utilization of prenatal diagnosis and its outcomes. The heterozygote identification rate and frequency of specific CFTR mutations were also assessed. Identified carriers were offered genetic counseling and testing of male partners. Prenatal diagnosis was offered if both parents were identified as carriers. A total of 5,161 women underwent carrier testing; 947 others completed survey instruments only. The acceptance rate of screening was high (78%), and pretest education by videotape was generally effective. Adverse psychological effects were not reported. Participants generally found screening to be desirable and useful. Screening identified 142 female heterozygotes, 109 couples in which the male partner was not a carrier, and 7 high-risk couples. The incidence of R117H mutations was much higher than expected. The number of identified carriers was much lower in Hispanics than in Caucasians. We conclude that large-scale prenatal screening for CF heterozygotes in the absence of a family history of CF is an acceptable method for identifying couples at risk for affected fetuses. Sufficient pretest education can be accomplished efficiently, test insensitivity is well accepted, adverse psychological events are not observed, and general patient satisfaction is high.

Causes of increasing mortality in a nursing home population

OBJECTIVE

To examine the roles played by changes in case-mix, quality of care, and aggressiveness of care in explaining the 42% increase in mortality of the Medicaid nursing home population of Hennepin County, Minnesota, between 1984 and 1988.

DESIGN

Retrospective chart review.

SETTING

All nursing homes in Hennepin County, MN, that care for Medicaid patients.

PATIENTS

A random sample of 1605 Medicaid nursing home residents from 1984 and 1988 stratified by year and by whether the resident died in that year. Sampling was disproportionate to allow approximately 400 individuals per stratum. A total of 1405 charts (87%) were reviewed; the remainder were either lost or destroyed.

MAIN OUTCOME MEASURES

Measures included case-mix (Charlson index, functional status, implicit reviewer assigned severity [range 1-4]), aggressiveness of care (orders limiting care), quality of care (process of care for tracer conditions [range 1-5], falls), and resident death.

RESULTS

Implicitly rated severity of illness worsened between 1984 and 1988 (2.77 vs 2.91; P = .009), but other measures of case-mix were unchanged. A greater percentage of residents had a DNR order in 1988 (12% in 1984 vs 37% in 1988; P < .001), and more received less aggressive care (31% vs 40%; P = .006). Overall process of care improved between 1984 and 1988 (2.88 vs 3.01; P < .05). With adjustment of the mortality rates and with logistic regression controlling for age and gender, changes in quality of care alone accounted for less than 5% of the mortality rate change between 1984 and 1988, case-mix alone accounted for 49%, and aggressiveness of care alone accounted for nearly 100%.

CONCLUSIONS

The nursing home population became sicker between 1984 and 1988, but process of care improved. These changes had a modest effect on the mortality rate. The increase in less aggressive care between 1984 and 1988 accounts for nearly all of the increase in mortality.

Changes in orders limiting care and the use of less aggressive care in a nursing home population

OBJECTIVE

To examine changes in the aggressiveness of care of the nursing home population and to determine the factors that predict whether care is limited.

DESIGN

Retrospective chart review.

SETTING

All nursing homes in Hennepin County, Minnesota that care for Medicaid patients.

PATIENTS

A random sample of 1605 residents of Hennepin County, MN nursing homes from 1984 and 1988 who were also Medicaid beneficiaries. The sample was stratified by year and by whether the resident died in that year. The residents were sampled disproportionately to allow approximately 400 individuals in each stratum. A total of 1405 charts (87%) was reviewed; the remainder had either been lost or destroyed.

MAIN OUTCOME MEASURE

Orders limiting care (do not resuscitate, supportive care only, etc.), care that was less aggressive than care usually given to a person of that age (eg, not using antibiotics for a clear infection or not sending a resident to the hospital for an illness for which someone would "usually" be sent to the hospital), determined implicitly through chart review.

RESULTS

The demographic characteristics of the nursing home population did not change between 1984 and 1988, but the population had significantly greater severity of illness in 1988. The percentage of residents with 'do not resuscitate' orders (DNR) increased from 12% to 37% (P < 0.0001), and the use of other orders to limit care (do not hospitalize, supportive care only, etc.) increased from 12% to 17% (P < 0.05). The use of CPR did not change between the two years but the percentage of residents who were found to receive less aggressive care through implicit chart review increased from 31% to 40% (P < 0.01). The year the resident was in the nursing home, the severity of illness, functional status, and dementia were significant predictors of DNR status. Factors that predict receipt of less aggressive care were similar except that age was also a significant predictor.

CONCLUSIONS

The nursing home population received less aggressive care in 1988 than in 1984. Further, there was a discrepancy between what was ordered and what was delivered in the nursing home in that residents with DNR orders had care limited beyond the withholding of CPR.

Clinical features of acetaminophen toxicity

Thirteen patients met our criteria for severe acetaminophen hepatotoxicity over a 5-year study period. Six patients had therapeutic misadventures (not attempting suicide), and seven were attempting suicide. Five of six patients in the therapeutic misadventure group were chronic alcoholics, and three were taking other drugs reported to cause hepatic microsomal enzyme induction. In the suicide group, two of seven patients were alcoholics, and one patient was taking another inducing drug. All six patients in the therapeutic misadventure group had nausea, vomiting, or starvation, whereas two of seven patients in the suicide group had similar characteristics. Starvation could deplete the protective factor glutathione, thus augmenting hepatotoxicity. In the therapeutic misadventure group, four of six patients developed acute tubular necrosis, as compared to two of seven in the suicide group. One patient died in each group. Clinicians should be aware of these features as part of the spectrum of acetaminophen toxicity.

Evidence for paracallosal verbal transfer after callosal section. A possible consequence of bilateral language organization

The covert interhemispheric transfer of linguistic information was demonstrated in a commissurotomy patient with bilateral language organization. It was found that under conditions of unilateral stimulation, a verbal association established in one hemisphere was available to the untrained hemisphere as well. Such interhemispheric transfer was observed only for phonetically codable information. Moreover, transfer was not observed under conditions of simultaneous bilateral stimulation. These results suggest that the point of convergence between the left and right hemisphere language systems allows for the paracallosal transfer of linguistic information.

Feasibility and implementation of a hospital-based group practice

All sectors of the economy have been suffering from the current inflationary environment. In some businesses, such as health care, costs have increased more than thought possible in the past. Since hospitals are labor intensive, they have been drastically affected by the push toward higher pay and the often hidden cost of fringe benefits. It is not surprising, therefore, that in seeking relief from the cost, hospitals will examine a method which removes a large part of the salary burden from their budgets: conversion of hospital-based salaried physicians to private, fee-for-service groups. The first article in this two-part series, which appeared in Medical Group Management, November/December 1981, examined the financial and legal aspects of the conversion. This concluding article presents the operational and organizational issues which must be considered for a successful conversion.