Pediatric donor heart acceptance practices in the United States: What is really being considered?

BACKGROUND

Recent studies demonstrate high offer decline and organ non-utilization rates are associated with increased pediatric heart transplant waitlist mortality. We sought to determine which donor, candidate, and offer specific variables most importantly influenced these decisions using only data available at the time of each offer.

METHODS

Retrospective review of pediatric (<18 years) heart donor offers made to pediatric candidates in the United States between 2010 and 2020. In addition to standard donor, candidate, and offer data available in UNOS, we extracted objective and qualitative valvar and myocardial function data from all available donor echocardiogram reports.

RESULTS

During the study period, 5625 pediatric donor hearts produced 30 156 offers to 4905 unique candidates, of which 88.7% of all offers were declined and 39.2% of organs were not utilized by pediatric waitlisted candidates. Of the 60.8% utilized hearts, 89.7% had a 'cumulatively' normal echocardiogram at the time of offer acceptance; 62.9% of hearts not utilized for a pediatric candidate also had a cumulatively normal final echocardiogram. Random forest and logistic regression modeling demonstrated good predictive performance (AUROC ≥0.83) of likelihood to accept when utilizing donor, candidate, and offer specific variables. SHAP variable importance scores demonstrated number of prior offer declines and candidate institution's prior year acceptance rates as the two most important variables influencing offer decisions.

CONCLUSIONS

Behavioral economics appear to play a significant role in pediatric heart transplant candidate institutions' acceptance practices, even when considering the arguably healthier pediatric donor population. Removal of prior institution's decisions from DonorNet may help increase donor utilization.

Gastrostomy tube placement in congenital cardiac surgery: a multi-institutional database study

INTRODUCTION

Neonates and infants who undergo congenital cardiac surgery frequently have difficulty with feeding. The factors that predispose these patients to require a gastrostomy tube have not been well defined. We aimed to report the incidence and describe hospital outcomes and characteristics in neonates and infants undergoing congenital cardiac surgery who required gastrostomy tube placement.

MATERIALS AND METHOD

A retrospective review was performed on patients undergoing congenital cardiac surgery between October 2015 and December 2020. Patients were identified by International Classification of Diseases 10th Revision codes, utilising the performance improvement database Vizient® Clinical Data Base, and stratified by age at admission: neonates (<1 month) and infants (1-12 months). Outcomes were compared and comparative analysis performed between admissions with and without gastrostomy tube placement.

RESULTS

There were 11,793 admissions, 3519 (29.8%) neonates and 8274 (70.2%) infants. We found an increased incidence of gastrostomy tube placement in neonates as compared to infants following congenital cardiac surgery (23.1% versus 6%, p = <0.001). Outcomes in neonates and infants were similar with increased length of stay and cost in those requiring a gastrostomy tube. Gastrostomy tube placement was noted to be more likely in neonates and infants with upper airway anomalies, congenital abnormalities, hospital infections, and genetic abnormalities.

DISCUSSION

Age at hospitalisation for congenital cardiac surgery is a definable risk factor for gastrostomy tube requirement. Additional factors contribute to gastrostomy tube placement and should be used when counselling families regarding the potential requirement of a gastrostomy tube.

Standardizing Prostaglandin Initiation in Prenatally Diagnosed Ductal-Dependent Neonates; A Quality Initiative

Prostaglandin E1 (PGE) is used in patients with ductal-dependent congenital heart disease (CHD). Side effects of apnea and fever are often dose dependent and occur within 48 h after initiation. We initiated a standardized approach to PGE initiation after our institution recognized a high incidence of side effects and a wide variety of starting doses of PGE. Neonates with prenatally diagnosed ductal-dependent CHD were identified, started on a standardized protocol that started PGE at 0.01 mcg/kg/min, and evaluated for PGE related side effects. Compliance, outcomes and dose adjustments during the first 48 h post-PGE initiation were evaluated. Fifty patients were identified (25 pre-intervention; 25 post-intervention). After intervention, compliance with the protocol was 96%, and apnea or fever occurred in 28% (compared to 63% pre-intervention, p = 0.015). Dose adjustments (either increase or decrease) prior to cardiac surgery were similar in both cohorts (60%, 52%, p = 0.569). There were no mortalities or emergent procedures performed due to ductus arteriosus closure. Standardizing a protocol for initiating PGE in prenatally diagnosed ductal-dependent CHD was successful and reduced the incidence of apnea, fever, and sepsis evaluations. A starting dose of 0.01 mcg/kg/min did not cause increased adverse effects.

Cardiac Concerns in the Pediatric Athlete

Cardiovascular disease remains the number one cause of death in Americans. It is no secret that exercise mitigates this risk. Exercise and regular physical activity are beneficial for physical health including aerobic conditioning, endurance, strength, mental health, and overall improved quality of life. Unfortunately, today many children and adolescents are sedentary, lacking the recommended daily amount of physical activity, leading to higher rates of obesity, cardiovascular disease, stroke, diabetes, anxiety, and depression. Given this rising concern, the World Health Organization launched a 12-year plan to improve physical activity in children and adolescents by reducing the inactivity rate by 15% in the world. How does this apply to children and adolescents with acquired or congenital heart disease?.

The impact and indications for Oncotype DX on adjuvant treatment recommendations when third-party funding is unavailable

OBJECTIVES

Industry-supported decision impact studies demonstrate that Oncotype Dx (ODX) changes treatment recommendations (TR) in 24-40% of hormone receptor+/HER2- patients. ODX is not reimbursed by third-party payers in Australia, potentially resulting in more selective use. We sought to evaluate the impact of self-funded ODX on TRs.

METHODS

Data collected included demographics, tumor characteristics, indication for ODX and pre- and post-recurrence score (RS) TR. Primary endpoint was frequency of TR change and associations with TR change were sought.

RESULTS

Eighteen physicians contributed 382 patients (median age 54). A total of 232 (61%) of tumors were T1 and were grade 1, 2 and 3 in 49 (13%), 252 (66%) and 79 (21%). A total of 257 (67%) were node negative. Assay indications were: confirm need for chemotherapy (CT) (36%), confirm omission of CT (40%) and genuine equipoise (24%). RS was low (≤17) in 55%, intermediate (18-31) in 36% and high (≥32) in 9%. Thirty-eight percent of patients had TR change post-ODX. Sixty-five percent of patients recommended CT pre-ODX changed to hormone therapy alone (HT)-more likely if lower grade and if ER and/or PR > 10%. Fourteen percent of patients with pre-ODX TR for HT added CT-more likely if ER and/or PR ≤10% and if Ki67 > 15% Overall, TR for CT decreased from 47% to 24%.

CONCLUSION

Patient-funded ODX changed TRs in 38% of patients, de-escalating 65% from CT to HT and adding CT to 14% of those recommended HT. These changes were greater than an industry-funded study suggesting that physicians can identify situations where the assay may influence decisions.

Increased risk of intraventricular hemorrhage in low birth weight infants with aortic coarctation

Objective: To determine if there is an association between aortic coarctation (CoA) and intraventricular hemorrhage (IVH) in low birth weight (LBW) infants that may justify earlier intervention. While there is an increasing number of reports of successful early CoA intervention in LBW infants, there are no data to justify this approach.Material and methods: Retrospective review of the University Health System Consortium Clinical Data Base/Resource Manager, a national hospital discharge database. LBW (≤2 kg) infants, with and without IVH and isolated CoA were identified; IVH was stratified into low (grade 1 or 2) and high (grade 3 or 4) severity. Odds ratios were calculated for any, low and high-grade IVH with CoA.Results: Forty-six thousand and twenty LBW infants were identified; 3716 (8.1%) had IVH, 3001 (81%) with low, and 724 (19%) with high severity. Sixty-four infants had CoA, 13 had associated IVH (10 with low and three with high severity). The odds ratio for any IVH with CoA was 2.91 (95% CI 1.58-5.35), low severity 2.77 (95% CI 1.41-5.46) and high severity 3.45 (95% CI 1.07-11.07).Conclusions: In conclusion, this large retrospective database review found that LBW infants with CoA may be at increased risk of IVH. Further study is needed to determine if earlier catheter- or surgical-based intervention for CoA could reduce the risk of IVH in this population.

Utility of three-dimensional models in resident education on simple and complex intracardiac congenital heart defects

OBJECTIVE

Applications of three-dimensional (3D) printed models in medicine include preprocedure planning, patient education, and clinical training. Reproducing complex anatomy as a 3D printed model can be useful for understanding congenital heart defects (CHD). We hypothesized that using 3D printed models during didactic sessions with resident physicians will improve trainees' understanding of CHD.

DESIGN AND INTERVENTION

We performed a prospective, randomized educational intervention for teaching pediatric and pediatric/emergency medicine residents about simple (ventricular septal defect [VSD]) and moderately complex (tetralogy of Fallot [ToF]) CHD. Residents were divided into two groups: intervention and control. Each group completed a subjective survey about their comfort with the anatomy, evaluation, and treatment of VSD and ToF and took an objective test on VSD and ToF. They separately received the same 20 min lecture, including projected two-dimensional digital images of VSD and ToF; the intervention group was given 3D printed models created using the same imaging data. After the lecture, the groups repeated the survey and test questions.

RESULTS

Twenty-six residents participated in the VSD session, 34 in the ToF. There were no differences in demographics between control and intervention groups. All residents had higher subjective comfort with VSD and ToF after the lectures. There was no difference in baseline test scores for VSD or ToF groups. The control group scored higher on the VSD postlecture test. The intervention group scored higher on the ToF postlecture test.

CONCLUSION

Incorporation of 3D printed models into lectures about CHD imparts a greater acute level of understanding, both subjective and objective, for pediatric and combined pediatric/emergency medicine residents. There does not seem to be an added benefit for understanding ventricular septal defects, but there is for tetralogy of Fallot, likely due to increased complexity of the lesion and difficulty visualizing spatial relationships in CHD with multiple components.

Treatment of tricuspid regurgitation and para-ring leak in tetralogy of Fallot with oversized SAPIEN 3 valve-in-ring implantation

A 40-year-old female with previously repaired tetralogy of Fallot had recurrent severe tricuspid regurgitation with a para-ring leak after annuloplasty ring placement. Because of multiple prior sternotomies and co-morbidities, she was not felt to be a surgical candidate. Percutaneous placement of an oversized SAPIEN 3 valve-in-ring in the tricuspid position successfully treated the regurgitation and para-ring leak.

Cardiovascular Considerations in the Female Athlete

Over several decades, much has been learned about the diverse physical impacts of exercise. Those who excel, such as elite athletes, have physiologic differences compared with the general population. There is a growing body of data suggesting that gender may play a role in these adaptations. Further, certain cardiac conditions may exhibit a gender predilection. This article explains the particular cardiac nuances of the female athlete.

Construction and performance of a dilution-refrigerator based spectroscopic-imaging scanning tunneling microscope

We report on the set-up and performance of a dilution-refrigerator based spectroscopic imaging scanning tunneling microscope. It operates at temperatures below 10 mK and in magnetic fields up to 14T. The system allows for sample transfer and in situ cleavage. We present first-results demonstrating atomic resolution and the multi-gap structure of the superconducting gap of NbSe(2) at base temperature. To determine the energy resolution of our system we have measured a normal metal/vacuum/superconductor tunneling junction consisting of an aluminum tip on a gold sample. Our system allows for continuous measurements at base temperature on time scales of up to ≈170 h.

A stiff scanning tunneling microscopy head for measurement at low temperatures and in high magnetic fields

We have developed a measurement head for scanning tunneling microscopy (STM) and specifically for spectroscopic imaging STM which is optimized for high mechanical stiffness and good thermal conductivity by choice of material. The main components of the microscope head are made of sapphire. Sapphire has been chosen from several competing possibilities based on finite element modeling of the fundamental vibrational modes of the body. We demonstrate operation of the STM head in topographic imaging and tunneling spectroscopy at temperatures down to below 2 K.

A comparative study of high-resolution cone beam computed tomography and charge-coupled device sensors for detecting caries

OBJECTIVES

Conventional radiographic imaging of teeth underestimates the presence of caries. The objective of this study was to compare the efficacy of high-resolution cone beam CT (CBCT) images and conventional charge-coupled device (CCD) images for detecting proximal and occlusal caries.

METHODS

Non-restored, extracted human permanent premolar and molar teeth were mounted and then imaged with a 3DX Accuitomo and a CCD. We selected 92 occlusal and 100 proximal surfaces for raters to score. Of these, 36 and 25, respectively, had lesions extending into dentin. Using a five-step confidence scale, eight practising dentists evaluated the images for the presence of caries in dentin using both modalities. Actual presence and extent of caries was established with microCT imaging.

RESULTS

For proximal surface lesions extending into dentin, the average sensitivity score using 3DX images (0.61) was almost twice that of CCD images (0.33) and the difference was significant. The specificity values for both systems were high and not significantly different from each other. For occlusal surfaces, raters detected significantly more lesions in the enamel or dentin when using the 3DX images than when using CCD images. However, the raters also had significantly lower average specificity scores for the 3DX images compared with the CCD images for lesions at both depths.

CONCLUSIONS

Practising dentists were able to improve their detection of proximal-surface caries extending into the dentin, but not occlusal caries, using 3DX high-resolution cone beam CT images compared with CCD images.

Observer performance in diagnosing osteoporosis by dental panoramic radiographs: results from the osteoporosis screening project in dentistry (OSPD)

Mandibular cortical erosion detected on dental panoramic radiographs (DPRs) may be useful for identifying women with osteoporosis, but little is known about the variation in diagnostic efficacy of observers worldwide. The purpose of this study was to measure the accuracy in identifying women at risk for osteoporosis in a worldwide group of observers using DPRs. We constructed a website that included background information about osteoporosis screening and instructions regarding the interpretation of mandibular cortical erosion. DPRs of 100 Japanese postmenopausal women aged 50 years or older who had completed skeletal bone mineral measurements by dual energy X-ray absorptiometry were digitized at 300 dpi. These were displayed on the website and used for the evaluation of diagnostic efficacy. Sixty observers aged 25 to 66 years recruited from 16 countries participated in this study. These observers classified cortical erosion into one of three groups (none, mild to moderate, and severe) on the website via the Internet, twice with an approximately 2-week interval. The diagnostic efficacy of the Osteoporosis Self-Assessment Tool (OST), a simple clinical decision rule based on age and weight, was also calculated and compared with that of cortical erosion. The overall mean sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the 60 observers in identifying women with osteoporosis by cortical erosion on DPRs were 82.5, 46.2, 46.7, and 84.0%, respectively. Those same values by the OST index were 82.9, 43.1, 43.9, and 82.4%, respectively. The intra-observer agreement in classifying cortical erosion on DPRs was sufficient (weighted kappa values>0.6) in 36 (60%) observers. This was significantly increased in observers who specialized in oral radiology (P<0.05). In the 36 observers with sufficient intra-observer agreement, the overall mean sensitivity, specificity, PPV, and NPV in identifying women with osteoporosis by any cortical erosion were 83.5, 48.7, 48.3, and 85.7%, respectively. The mean PPV and NPV were significantly higher in the 36 observers with sufficient intra-observer agreement than in the 24 observers with insufficient intra-observer agreement. Our results reconfirm the efficacy of cortical erosion findings in identifying postmenopausal women at risk for osteoporosis, among observers with sufficient intra-observer agreement. Information gathered from radiographic examination is at least as useful as that gathered from the OST index.

Comparative study of image quality for MSCT and CBCT scanners for dentomaxillofacial radiology applications

The image quality of four cone-beam computed tomography (CBCT) scanners dedicated for dentomaxillofacial imaging and one multi-slice computed tomography (MSCT) scanner was compared. For the MSCT scanner, a clinical and a low-dose protocol for oral indications were evaluated. The image quality was assessed by dedicated software that allows an automated analysis of accuracy measurements and evaluation of metal artefacts on two image quality phantoms. Bone was segmented with sub-millimetre accuracyin all scanners.

Gallbladder management during laparoscopic Roux-en-Y gastric bypass surgery: routine preoperative screening for gallstones and postoperative prophylactic medical treatment are not necessary

In the bariatric surgery literature, the optimum approach to the gallbladder is controversial. Recommendations range from concomitant cholecystectomy to selective screening and postoperative medical prophylaxis. At our institution, we have taken a highly selective approach where patients are not routinely screened for gallstones, nor are they medically treated postoperatively with bile salts. We have reviewed our experience with this approach. From January 2003 to January 2005, 407 laparoscopic Roux en Y gastric bypasses were performed at UCLA and postoperative outcomes were collected into a prospective database. Exclusion criteria included previous cholecystectomy, a follow-up period less than 6 months, or incomplete records. One hundred ninety-nine patients were included in the study. With a mean follow up period of 17.8 months, 12 (6%) patients required cholecystectomy for gallstone-induced pathology. Laparoscopic removal was performed in 11 (92%) patients. Indications for surgery included acute cholecystitis in five (2.5%) patients, gallstone pancreatitis in two (1%) patients, and biliary colic alone in another five (2.5%) patients. The incidence of symptomatic gallstones requiring cholecystectomy after laparoscopic Roux en Y gastric bypass is low. These results are similar to those from institutions where routine preoperative screening and prophylactic postoperative medical therapy is used. Routine preoperative screening or medical prophylaxis may not be necessary.

Phase II study of SPI-77 (sterically stabilised liposomal cisplatin) in advanced non-small-cell lung cancer

To determine the efficacy and tolerability of SPI-77 (sterically stabilised liposomal cisplatin) at three dose levels in patients with advanced non-small-cell lung cancer (NSCLC). Patients had Stage IIIB or IV NSCLC and were chemo-naïve, and Eastern Oncology Cooperative Group 0-2. The first cohort received SPI-77 at 100 mg m-2, the second 200 mg m-2 and the final cohort 260 mg m-2. Patients had also pharmacokinetics and analysis of leucocyte platinum (Pt)-DNA adducts performed. Twenty-six patients were treated, with 22 patients being evaluable for response. Only one response occurred at the 200 mg m-2 dose level for an overall response rate of 4.5% (7.1% at >or=200 mg m-2). No significant toxicity was noted including nephrotoxicity or ototoxicity aside from two patients with Grade 3 nausea. No routine antiemetics or hydration was used. The pharmacokinetic profile of SPI-77 was typical for a liposomally formulated drug, and the AUC appeared to be proportional to the dose of SPI-77. Plasma Pt levels and leucocyte DNA adduct levels did not appear to rise with successive doses. SPI-77 demonstrates only modest activity in patients with NSCLC.

Change in mandibular trabecular pattern and hip fracture rate in elderly women

OBJECTIVES

To determine if alterations of trabecular pattern, or the rate of change of jaw trabeculae, are associated with rate of hip fracture.

METHODS

Participants in a population-based study of residents of a California retirement community (Leisure World Cohort Study) were asked for permission to obtain their dental radiographs. Periapical radiographs were retrieved on 598 women (average age at time of first radiograph=77 years). Several measurements of trabecular pattern (strut analysis), textural properties (run-length analysis) and Fourier analysis were made in several anatomical regions of the jaw. These trabecular features and clinical information self-reported by subjects in the early 1980s were examined for association with hip fracture rate using Cox proportional-hazard regression.

RESULTS

Rate of hip fracture increased with decreasing average length of node-to-terminus struts in the mandibular incisor region. Each 0.01 mm per year decrease in the average length of node-to-terminus struts increased hip fracture rate by a factor of 2.9 (P=0.02, accuracy=73%). Inclusion of clinical parameters improved the predictive model compared with use of the radiographic parameter alone (accuracy=79%). Similar results were seen for percent change per year in this parameter.

CONCLUSIONS

Changes in radiographic trabecular structure, augmented with clinical information, are predictive of hip fracture in elderly women. Further refinement of both the radiographic and clinical parameters may lead to a screening process accessible to a large number of women and to early diagnosis and treatment of osteoporosis.

Effects of weightlessness on astronauts--a summary

This paper reviews the adaptive changes observed in the United States astronauts during flight programs to this date. A series of postulates are offered as to what is happening in these adaptive events. A hypothesis is proposed as to the interrelationship of events observed in the body systems and functions involved. The importance of undertaking an extensive life sciences program. including an on-orbit phase of study as well as pre- and post-flight studies is discussed. Finally, the role the Skylab flight plays in the United States Space Program in achieving the future requirements for more extensive life sciences data is summarized.

Oral radiographic predictors of osteoporosis

Osteoporosis is a systemic skeletal disease characterized by low bone mass and micro architectural deterioration of the bone scaffold that result in increased bone fragility and susceptibility to fracture. It is one of the most common disorders of the elderly and is estimated to effect 75 million people in Europe, Japan and the USA. The purpose of screening for osteoporosis is to identify individuals who are likely to benefit from treatment. The fact that dental radiographs are regularly made on a large fraction of the adult population makes their potential use as a marker of skeletal health an exciting avenue of research. In the last four decades numerous research teams have reported oral radiographic findings associated with osteoporosis. The preponderance of the evidence shows that the jaws of subjects with osteoporosis show reduced bone mass and altered morphology. Clinically useful predictions of individuals most likely to develop osteoporotic fractures will require a multifactorial model including both radiographic and clinical findings. Future efforts should continue to search for oral radiographic signs with high sensitivity and specificity for osteoporosis, identify clinical signs available in the dental office associated with osteoporosis, develop multidisciplinary classification methods including both radiographic and clinical parameters, and automate radiographic and clinical analyses as much as possible to minimize the involvement of the dentist as well as to standardize data collection.

Fourier analysis reveals increased trabecular spacing in sickle cell anemia

Sickle cell anemia may expand marrow spaces in the jaws. Fourier analysis is well-suited to the analysis of trabecular spacing in radiographs. We hypothesize that individuals with sickle cell anemia demonstrate increased intertrabecular spacing. Periapical radiographs of 18 African Americans with sickle cell disease and 18 controls were examined by one-dimensional discrete Fourier analyses in both jaws for measurement of the spatial frequency distribution of repeating trabecular structures. A strut analysis of trabeculae was also performed and the results compared. Trabecular structures in individuals with sickle cell anemia revealed increased intertrabecular distance compared with controls. Strut analysis revealed significant reductions in trabecular complexity. Fourier analysis allows for the classification of subjects with 94% sensitivity and specificity. Fourier analysis of dental radiographs is a more effective method of identifying individuals with sickle cell anemia than strut analysis.

Vertical ground reaction forces: objective measures of gait following hip arthroplasty

After hip arthroplasty, many patients continue to exhibit abnormal gait patterns. The purpose of this study was to compare the vertical ground reaction forces of a group of 27 individuals who have undergone hip arthroplasty with a group of 35 normal control subjects. Specific force measures were determined from vertical ground reaction forces collected on a treadmill instrumented with two force plates. Symmetry indices were calculated on both groups of subjects. First and second peak forces, loading rate, impulse, and stance time were significantly less, while time to first peak force was significantly greater on the affected leg of the hip arthroplasty subjects when compared to their unaffected leg, or to the control group. The hip arthroplasty group showed greater asymmetry of ground reaction forces than the control group did. Bilateral asymmetric limb loading persists well after unilateral hip replacement surgery. Ground reaction force measures have been shown to be an effective means of quantifying the antalgic gait of hip arthroplasty patients.

Randomized phase II study of cyclophosphamide, doxorubicin, and vincristine compared with single-agent carboplatin in patients with poor prognosis small cell lung carcinoma

BACKGROUND

Information on the effect of chemotherapy in a group of patients with poor prognosis, poor performance status small cell lung carcinoma (SCLC) is scarce. A randomized study comparing single-agent carboplatin with combination chemotherapy in this largely unreported population of SCLC patients was undertaken.

METHODS

One hundred nineteen patients were allocated to four cycles of either cyclophosphamide, doxorubicin, and vincristine (CAV) or single-agent carboplatin. Patients had either a Karnofsky performance score < or = 50 and/or a prognostic score indicative of a 1-year survival rate < or = 15%.

RESULTS

Grade 3-4 neutropenia and intravenous antibiotic use were significantly more common with the CAV regimen (P < 0.005). Conversely, Grade 3-4 thrombocytopenia was more common (P < 0.0009) and platelet transfusion was more frequent (P < 0.05) with carboplatin therapy. Nonhematologic toxicity was similar in both treatment arms, except for alopecia with CAV therapy (P < 0.0007). Symptom relief occurred in 48% and 41% of patients in the CAV and carboplatin treatment arms, respectively. Dyspnea was improved in 66% and 41% of patients and cough was improved in 21% and 7% of patients in the CAV and carboplatin treatment arms, respectively. CAV therapy produced a higher response rate than carboplatin (38% vs. 25%), but this was not statistically significant (P = 0.15). The median overall survival for patients in the CAV and carboplatin treatment arms was 17 weeks and 15.9 weeks, respectively, with 1-year survival rates of 12% and 6%.

CONCLUSIONS

Single-agent carboplatin is a feasible treatment in patients with poor prognosis SCLC and produces response rates, relief of tumor-related symptoms, and survival similar to what is seen in patients who receive CAV chemotherapy. The lower risk of life-threatening sepsis and less need for hospitalization or intravenous antibiotic courses is advantageous in this susceptible patient population.

Effect of localized muscle fatigue on vertical ground reaction forces and ankle joint motion during running

The purpose of this study was to examine the changes in the vertical ground reaction force (VGRF) and ankle joint motion during the first 50% of the stance phase of running following fatiguing exercise of either the dorsiflexors or the invertors of the foot. VGRFs, sagittal and rearfoot kinematic data were collected from 11 female recreational runners running at 2.9 m/second on a treadmill prior to and following localized muscle fatigue of either the invertors or dorsiflexors of the right foot. Loading rate of the impact peak force significantly increased following fatiguing exercise of the dorsiflexors, while the peak magnitudes of the impact and push-off forces remained unchanged. There were significant decreases in dorsiflexion at heel contact, but no significant difference in any rearfoot motion parameters tested following dorsiflexor fatigue. Following fatiguing exercise of the invertors, impact peak magnitude, push-off peak magnitude and the rate of decline of the impact peak force significantly decreased; there was no change in the loading rate of the impact peak force. Invertor fatigue also resulted in a less inverted foot position at heel contact, but there were no significant differences in any other kinematic parameters tested. The results demonstrate that localized muscle fatigue of either the invertors or dorsiflexors can have a significant effect on the loading rates, peak magnitudes and ankle joint motion seen during running. These changes, due to localized muscle fatigue, may play a role in many common lower extremity running injuries.

Parameters of radiologic care: An official report of the American Academy of Oral and Maxillofacial Radiology

The American Academy of Oral and Maxillofacial Radiology developed these Parameters of Care to provide national guidelines for the use of radiographs prescribed for the diagnosis of disease, treatment planning, and follow-up care of patients with abnormalities of the oral and maxillofacial region. The Parameters cover radiographic techniques, imaging of the temporomandibular joint, imaging of diseases of the jaws, and imaging of dental implant sites.

Comparison of sensitometric and diagnostic performance of two films

The sensitometric properties of Kodak Ektaspeed Plus and Flow E-speed film as well as their diagnostic efficacy for detecting proximal surface caries were compared. Flow and Kodak E-speed films were exposed and processed according to American National Standards Institute and American Dental Association (ADA) specifications, and film speed, contrast, and density of base plus fog were measured. Additionally, 80 premolar and molar teeth were imaged and their proximal surfaces scored by 12 dentists for the presence of caries. The actual depth of the caries was determined by microscopic examination of the teeth after sectioning. Kodak Ektaspeed Plus and Flow E-speed films, although labeled E-speed by the manufacturers, are both slow F-speed films. They have comparable base plus fog densities and comparable contrast curves. Dentists detected carious lesions equally well using both film types. The sensitivity, specificity, accuracy, and receiver operating characteristic area for detecting enamel and dentinal caries were not significantly different between the two films. Kodak Ektaspeed Plus and Flow E-speed films both meet or exceed the ADA performance specifications in terms of sensitometric properties. Both offer equal diagnostic utility for detecting caries.

Phase II study of oral topotecan in advanced non-small cell lung cancer

This study was designed to assess the activity of oral topotecan (TPT) in patients with advanced non-small cell lung cancer previously untreated with chemotherapy. Eligible patients had inoperable stage III or stage IV non-small cell lung cancer and were chemotherapy-naive. Other inclusion criteria were Eastern Cooperative Oncology Group performance status 0, 1, or 2, adequate bone marrow, and renal and hepatic function. Of 30 patients, 29 were assessable for response. Oral TPT was administered for 5 days every 21 days for up to six cycles unless disease progression or unacceptable toxicity occurred. Patients received a dose of 2.3 mg/m2/day for the first cycle. Dose modification for subsequent cycles was based on tolerability. Patients completed symptom questionnaires every 3 weeks. Pharmacokinetics were evaluated in all patients during cycle 1. Three patients had radiological responses with a reduction in tumor size of 30-40%. No patients achieved complete or partial responses to treatment. Thirteen patients had a stable disease (43.3%), and the median survival was 39.9 weeks with a 1-year survival of 33.3%. At the time of analysis, 27 patients had died. Median time to progression was 12.3 weeks. Treatment was well tolerated. A total of 125 cycles of treatment were completed. Twelve patients (40%) experienced grade III/IV neutropenia. Five patients (16.6%) had grade III/IV anemia. There were two episodes of grade III/IV thrombocytopenia. The main nonhematological toxicities consisted of grade III nausea (13%) and grade III vomiting (13%). The most frequently reported disease-related symptoms at baseline were dyspnea, cough, and fatigue. There was a subsequent improvement in patient scores of dyspnea in 17% of patients, 31% showed improvement in cough, and 32% showed improvement in fatigue. The mean area under the curve of TPT following 2.3 mg/m2 p.o. was 51.6 ng.h/ml (%SD, 25%). The area under the curve of TPT on day 1 of the first cycle was correlated with the percentage fall in leukocytes. Although oral TPT at the applied dose and schedule showed modest activity as a single agent, almost one-half of the patients had a stable disease, and median time to progression was 12.3 weeks. The overall median survival was a promising 39.9 weeks, and useful palliation of symptoms was seen.

Digital analysis of trabecular pattern in jaws of patients with sickle cell anemia

OBJECTIVES

To characterize how the morphological features of the cancellous bone of the maxilla and mandible differ in patients with sickle cell anemia compared with normal subjects.

METHODS

Periapical radiographs of 18 young African American patients with sickle cell anemia and 18 control African Americans were digitized at 600 d.p.i. A customized computer program measured 24 morphological features of the trabecular and marrow architecture in the anterior maxilla and mandible. The mean values for each of the features were determined for the sickle cell and control groups and compared by anatomical site.

RESULTS

Patients with sickle cell anemia have a significant increase in area of the marrow (53% compared with 47% in controls) and a less complex trabecular structure as evidenced by fewer skeletal branch points per square cm (451 compared with 584 in controls in the anterior maxilla and, 553 compared with 678 in controls in the anterior mandible). All values are significantly different (P < 0.001).

CONCLUSIONS

The data support the hypothesis that an automated image-interpretation program can distinguish patients with sickle cell anemia from normal individuals.

Randomised phase II study of cisplatin-etoposide versus infusional carboplatin in advanced non-small-cell lung cancer and mesothelioma

BACKGROUND

A randomised phase II study was performed to compare standard combination chemotherapy containing cisplatin and etoposide with infusional carboplatin.

PATIENTS AND METHODS

One hundred twenty patients with locally advanced/metastatic non-small-cell lung cancer or mesothelioma were enrolled. All were chemotherapy-naïve and had a Karnofsky performance status of > or = 50. Patients were randomised to either four cycles of bolus therapy of cisplatin 80 mg/m2 day 1, etoposide 120 mg/m2 day 1-3, or continuous infusion of carboplatin 100/mg/m2/week for six weeks.

RESULTS

No patients on infusional therapy incurred grade 3-4 toxicity while in the bolus arm, grade 3 and grade 4 leucopenia occurred in 17% and 35% of patients, respectively. Grade 4 thrombocytopenia occurred in 8% of patients and there were two instances of grade 3 renal toxicity. No responses occurred in the pump arm. Eight of forty-six patients with non-small-cell lung cancer responded to treatment (response rate 17.3%) with two complete responses and six partial responses. Only one patient with mesothelioma responded to bolus therapy. There was no difference in survival for the subset of NSCLC patients. Survival for mesothelioma patients in the pump arm was superior but this was likely to be a result of early deaths in the bolus arm.

CONCLUSIONS

The pump arm was well-tolerated but not active, whilst combination platinum-based therapy demonstrated activity but significantly more toxicity than the pump arm. Further studies of infusional carboplatin with this schedule are not warranted.

Digital radiography in dentistry: what it should do for you

Digital radiology will become an important part of dental practice. Manufacturers should develop more sophisticated tools, including software for digital subtraction; image processing routines for the diagnosis of caries, periodontitis and periapical disease; tools for three-dimensional viewing of the teeth and supporting structures; and analysis of bone trabecular pattern for early detection of systemic disease. Hardware improvements should include increased dynamic range and sensitivity to radiation, and improved resolution. Sensors should be made the size of film, and components should be interchangeable across manufacturers. The true opportunity offered by digital imaging, computer-aided diagnosis, should continue to develop with particular attention to development of tools that add value for solving diagnostic problems and ease of use for the dentist and patient.

Alterations of the trabecular pattern of the jaws in patients with osteoporosis

OBJECTIVE

The purpose of this study was to determine whether the morphologic features of the trabecular bones of the maxilla and mandible differ between patients with osteoporosis and normal controls.

STUDY DESIGN

Periapical radiographs, obtained from dentists of 11 patients with osteoporosis and 12 control subjects, were digitized at 600 dpi. A custom computer program measured morphologic features of the trabecular architecture. The mean values for each feature were determined for the osteoporotic and control groups and compared by anatomic site.

RESULTS

Twenty-four morphologic features of the trabeculae and marrow regions were examined in each anatomical site. A principal components analysis summarized these predictors to four. The Hotelling T (2) test found that patients with osteoporosis had significantly altered morphologic pattern in the anterior maxilla (P =.019) and the posterior mandible (P =.013) in comparison with the controls. A classification tree analysis separated all subjects into 2 groups with 92% accuracy.

CONCLUSIONS

The data support the hypothesis that patients with osteoporosis have an altered trabecular pattern in the jaws in comparison with normal subjects.

Findings of clinical and radiographic caries among several adult age groups

OBJECTIVE

The purpose of this study was to determine whether there are aged-based variations in the association between clinically detected and radiographically detected caries and whether the prevalence of clinically undetected radiographic caries varies across adult age groups.

STUDY DESIGN

The data for the analysis were from a clinical study that evaluated the efficacy of guidelines for prescribing dental radiographs. A total of 460 subjects had clinical examinations and interpretation made on full-mouth radiographs. Analysis was conducted to determine the tooth-specific and subject-specific prevalences of clinically undetected caries and to establish whether the association between clinical signs and radiographic signs varied by subject age.

RESULTS

In total, approximately 5.8% of clinically sound teeth showed radiographic evidence of dentinal caries, and the prevalence increased with patient age. The prevalence of clinical signs of medium and large caries was 7.8% in 12,358 teeth in which caries was both clinically and radiographically present. However, for more than 80% of the teeth with clinically undetected caries, the lesions were evident on the interproximal radiographs. The associations between clinical and radiographic signs of dentinal caries were homogeneous across age groups.

CONCLUSION

The findings demonstrate that adolescents and adults continue to have medium and large caries, although the location of the caries differs by age group, with higher proportions of gingival caries in older patients.

Consistency of patient classification in orthodontic diagnosis and treatment planning

The purpose of this study was to examine diagnosis and treatment planning categorizations used by experienced orthodontists. Thirty-nine clinicians were asked to evaluate six test cases and formulate a diagnosis and treatment plan for each. The information provided was categorized using a problem-oriented classification. The results indicate little agreement exists in diagnostic subcategories, such as molar relationship, degree of crowding, or the nature of skeletal discrepancies. There was also little agreement regarding some treatment strategies, such as extraction of teeth, the use of orthopedic appliances, or the use of surgery. A need exists for better definitions of diagnostic criteria and appropriate treatment options.

Comparison of vertical ground reaction forces during overground and treadmill walking

PURPOSE

The purpose of this study was to compare vertical ground reaction forces walking overground with vertical foot-belt forces for treadmill gait.

METHODS

Twenty-four subjects walked overground and on a treadmill at three speeds (slow, normal, and fast), and at comparable cadences and stride length at each of the speeds. Treadmill and overground vertical force curves were normalized to 100% of stance time and compared using Person's product moment correlation. Selected measures from vertical force records were compared between the two modes of locomotion via repeated measures ANOVA (P < 0.05). Post-hoc analysis consisted of paired t-tests with Bonferroni correction. All comparisons were made across conditions (treadmill vs overground) at each of the three walking speeds.

RESULTS

The pattern of reaction forces were similar. Correlation between curves were 0.998, 0.983, and 0.983 for the slow (1.03-1.05 m.s-1), normal (1.40-1.44 m.s-1) and fast (1.65-1.71 m.s-1) walking trials. Small (5-9%) but significant differences in force magnitude for the two forms of locomotion were evident during mid-stance for normal (P = 0.00009) and fast (P = 0.0007) walking speeds and in late stance for normal (P = 0.0014) and fast (P = 0.0005) trials.

CONCLUSIONS

Although the patterns of the vertical reaction forces for the two forms of locomotion were nearly identical, small but significant differences in selected force magnitudes were evident. The interpretation of locomotion data collected on a treadmill should consider that forces during mid- and late-stance may be different than if the subject walked overground.

The Lovelace Award presentation of the Society of NASA Flight Surgeons

The following speech was presented at the Society of NASA Flight Surgeon's annual luncheon meeting on May 11, 1995 in Anaheim, CA. The Randolph C. Lovelace Award is presented annually by the Society. Stanley C. White, M.D., had a very distinguished career in Aerospace Medicine, including working with the Air Force's Man-In-Space and Man-In-Space-Soonest Programs, and, later, as the first Flight Surgeon assigned to the NASA Space Task Group. For these, and numerous other contributions, Dr. White was chosen to receive the Society of NASA Flight Surgeons' 1995 Lovelace Award at the 66th Annual Scientific Meeting of the Aerospace Medical Association. Dr. White, who was a personal acquaintance of Dr. Randy Lovelace for whom the award is named, then captivated the audience with a fascinating speech about Dr. Lovelace. Furthermore, he admonished us to remember the legacy of Dr. Lovelace and the many lessons his wisdom still teaches us today. The following is Dr. White's presentation.

Imaging of the temporomandibular joint: a position paper of the American Academy of Oral and Maxillofacial Radiology

Various imaging techniques for the temporomandibular joint are discussed with respect to uses, strengths, and limitations. An imaging protocol is outlined for evaluating patients with a wide variety of temporomandibular joint related signs and symptoms.

Muscle function and gait in patients with knee osteoarthritis before and after muscle rehabilitation

Patients with knee osteoarthritis (OA) have reduced functional capacity and muscle function that improves significantly after quantitative progressive exercise rehabilitation (QPER). The effects of these changes on the biomechanics of walking have not been quantified. Our goal was to quantify the effects of knee OA on gait before and after QPER. Bilateral kinematic and kinetic analyses were performed using a standard link-segment analysis on seven women (60.9 +/- 9.4 years) with knee OA. All functional capacity, muscle function and gait variables were initially reduced compared to age-matched controls. Muscle strength, endurance and contraction speed were significantly improved (55%, 42% and 34%, respectively) after 2 months of QPER (p < 0.05), as were function (13%), walking time (21%), difficulty (33%) and pain (13%). There were no significant changes in the gait variables after QPER. To use the QPER improvements to the best advantage, gait retraining may be necessary to "re-programme' the locomotor pattern.

Orthodontic residents' indications for use of the lateral TMJ tomogram and the posteroanterior cephalogram

The purpose of this study was to determine the selection criteria used by orthodontic residents for ordering a corrected lateral tomogram (LT) of the temporomandibular joint (TMJ) and a posteroanterior cephalogram (PAC) for the diagnosis of patients needing orthodontic care. The impact of the radiographs on their treatment plans was also assessed. We conducted a study of the 144 new patients assigned to eight orthodontic residents during a two-year period. The residents responded through questionnaires describing their rationale for ordering the radiographs. A LT was ordered for twenty-eight (19 percent) of the patients. The most common reasons cited for requesting the LTs were TMJ clicking (67 percent) and pain (33 percent). The residents also perceived a need to order the LT for medico-legal protection in 85 percent of these cases. The LT tended not to have an impact on treatment planning. A PAC was ordered thirty-eight times (26 percent). The most common reasons cited by residents for ordering a PAC included clinical findings of facial asymmetry (41 percent) and maxillary airway anatomy (24 percent). Medico-legal protection was a perceived need in only 12 percent of the cases. While the PAC had no impact on treatment planning for 56 percent of the cases, they did define the transverse problems as dental or skeletal for 38 percent of the cases. Six patient traits were statistically associated with PAC requests: difficulty chewing, abnormal TMJ, TMJ clicking, facial asymmetry. crossbite, and midline discrepancy. The teaching of appropriate selection criteria for ordering these radiographs needs to be emphasized early in a resident's training.

Comparative performance of digital and conventional images for detecting proximal surface caries

OBJECTIVE

To evaluate the performance of a digital CCD system for detecting proximal surface caries compared with film.

METHOD

Three hundred and twenty extracted human teeth were imaged by making direct digital (Schick Technologies, Inc) and conventional film images (E-speed) of each. A total of 16 experienced dentists scored the proximal surfaces of these teeth for the extent of enamel and dentin lesions. The teeth were subsequently sectioned to determine the actual caries depth.

RESULTS

The sensitivity of the CCD system was consistently lower than film while the specificity of the CCD system was consistently higher. The accuracy of CCD and film images was not significantly different, neither when sensitivity and specificity were averaged nor when accuracy was weighted to reflect caries prevalence of 2, 5 or 10%. The predictive values of both positive/negative outcomes were virtually identical for the CCD and film images. The interrater variability in lesion confidence scores with digital images was comparative with film.

CONCLUSIONS

Dentists using a direct digital CCD system performed as well in interpreting proximal surface caries as with E-speed film. This work suggests that for this task these two competing systems are diagnostically comparable.

Relationships between clinician variability and radiographic guidelines

This study evaluated the replicability of clinical measurements under careful calibration of multiple dentists and how the replicability can relate to their use as selection criteria in guidelines for prescribing dental radiographs. For 48 consenting patients, three dentists clinically examined each patient and recorded the presence of all clinical findings using standardized selection criteria. The examinations were performed independently of each other, but with periodic conferences of the dentists to clarify general measurement criteria. The degree of agreement among the dentists is described by the interrater agreement kappa for several standard clinical indications such as rating of caries, periodontal disease, and tooth mobility. Almost perfect agreement was obtained for tooth status, restoration size, and restoration material. Moderate agreement resulted for measures of caries, defective restoration presence, and gingival recession presence. Only fair agreement was obtained for other periodontal disease measures. The relationship between extent of agreement and guidelines' results was examined for the FDA Guidelines. The differences among the dentists' clinical measurements resulted in considerable differences among the radiographs that were selected by the FDA Guidelines' criteria. Even so, the missed disease rates for 490 patients in a larger study of the FDA Guidelines' efficacy were very low and did not vary greatly among the three dentists. We conclude that guidelines' criteria can be quite robust to variation from dentists' clinical measurement differences, as seen from the FDA Guidelines applied under the idealized setting where the dentists are periodically recalibrated through group discussions of the clinical measurements' definitions and interpretations.

Decision-support systems in dentistry

Decision-support systems hold a specialized body of knowledge in computerized form such that the non- specialist can obtain expert-level information. The goal of these systems in clinical sciences is usually to assist patient care by providing the clinician with improved diagnosis or treatment planning. Decision-support systems consist of three components: the user interface through which the clinician or patient enters signs or symptoms, the set of data describing clinical knowledge in the domain of the program, and an inference engine to manipulate the data set in light of a patient's specific signs or symptoms to arrive at a diagnosis or treatment plan. Such systems usually use one of three mechanisms of analysis alone or in combination: classification trees, Bayesian conditional probabilities, or rule-based (heuristic) systems. Numerous problems must be solved before decision-support systems will become commonplace in clinical practice. Data entry of patients' signs and symptoms is often tedious. The quality of the clinician's initial observations is of great importance in determining the quality of the output. It is also often difficult to convey to a program the subtlety of clinical information observed. Knowledge required in clinical data bases is often unavailable or imprecise. As these and other challenges are addressed we can anticipate increased utility of decision support programs in the future.

Assessing the FDA guidelines for ordering dental radiographs

In 1988, the U.S. Food and Drug Administration issued guidelines to help dentists reduce the amount of X-ray exposure to patients without reducing the quality of care. This study assesses the efficacy of those guidelines. The authors examined 490 patients and ordered radiographs as indicated by the FDA guidelines. Using the guidelines, they ordered a mean of 9.7 radiographs out of a 17-film series, a reduction of 43 percent compared with a full-mouth series. The authors conclude that dentists can reduce a patient's exposure to X-rays by using these guidelines with a low level of missed radiographic findings, most of which would have no effect on the patient's treatment.