Overturned abusive head trauma and shaken baby syndrome convictions in the United States: Prevalence, legal basis, and medical evidence.

BACKGROUND: Media reports and the Innocence Network assert that wrongful Abusive Head Trauma (AHT)/Shaken Baby Syndrome (SBS) convictions pervade the United States (U.S.) criminal justice system. Yet, no empirical evaluation of overturned AHT/SBS convictions has been conducted. OBJECTIVE: To evaluate the prevalence, legal basis, and characteristics of appellate rulings of AHT/SBS convictions. PARTICIPANTS AND SETTING: U.S. appellate cases in a legal database, Westlaw. METHODS: Retrospective review of AHT/SBS convictions that had appellate rulings from January 2008 through December 2018. Multiple search terms ensured all potential AHT/SBS cases were included. A mixed-methods analysis was conducted on overturned AHT/SBS convictions. RESULTS: We identified a total of 1431 unique AHT/SBS criminal convictions that had appellate rulings since 2008. Of those, 49 convictions (3%) were overturned, and 1382 (97%) were affirmed/upheld. Of those overturned, 20 cases (1% overall) were overturned on medical evidence-related grounds. The most common themes from the medical evidence-related reversals were controversy over the AHT/SBS diagnosis (n = 12) and accidental injury mechanism (n = 11). After being overturned on appeal, upon retrial, 42% of defendants either re-plead guilty to or were convicted again of the same offense. CONCLUSION(S): AHT/SBS convictions are rarely overturned on medical evidence-related grounds. When overturned, medical evidence-related themes seldom reflect new scientific or clinical discoveries, but rather are alternative or differing medical opinions from those offered at the original trial. Our data tends to support the concerns of other authors regarding irresponsible communication of medical information in AHT/SBS cases.

Morphomechanics of dermis-A method for non-destructive testing of collagenous tissues.

BACKGROUND: Collagenous tissues store, transmit and dissipate elastic energy during mechanical deformation. In skin, mechanical energy is stored during loading and then is dissipated, which protects skin from mechanical failure. Thus, energy storage (elastic properties) and dissipation (viscous properties) are important characteristics of extracellular matrices (ECMs) that support the cyclic loading of ECMs without tissue failure. METHODS: Uniaxial stress-strain measurements on decellularized human dermis have been made and compared to results of a non-destructive technique involving optical coherence tomography (OCT) combined with vibrational analysis. In addition, Poisson's ratio has been determined for tensile deformation of decellularized dermis. RESULTS: The modulus of decellularized dermis measured using standard tensile stress-strain tests and that determined from calculations derived from natural frequency measurements give similar results. It is also observed that Poisson's ratio for dermis is between 0.38 and 0.63 after correction for changes in volume that occur during tensile deformation. These results suggest that the assumption that dermis and other ECMs deform at constant volume is incorrect and will lead to differences in the calculated modulus by conventional tensile stress-strain measurements. CONCLUSIONS: It is proposed that OCT in conjunction with vibrational analysis is a convenient way to non-destructively measure the modulus of decellularized dermis, ECMs and other materials that have a positive curvature to their stress-strain curves. Tensile deformation of dermis and possibly other ECMs is associated with an increase in Poisson's ratio consistent with a model of fluid expulsion from collagen fibrils during stretching. The value of Poisson's ratio should be considered in analyzing the mechanical properties of ECMs since at least dermis appears to be compressible during tensile deformation. Fluid expression during tensile deformation may play a role in mechanotransduction in skin in a similar manner to cartilage and bone tissue.

Accuracy and interrater reliability for the diagnosis of Barrett's neoplasia among users of a novel, portable high-resolution microendoscope.

The high-resolution microendoscope (HRME) is a novel imaging modality that may be useful in the surveillance of Barrett's esophagus in low-resource or community-based settings. In order to assess accuracy and interrater reliability of microendoscopists in identifying Barrett's-associated neoplasia using HRME images, we recruited 20 gastroenterologists with no microendoscopic experience and three expert microendoscopists in a large academic hospital in New York City to interpret HRME images. They prospectively reviewed 40 HRME images from 28 consecutive patients undergoing surveillance for metaplasia and low-grade dysplasia and/or evaluation for high-grade dysplasia or cancer. Images were reviewed in a blinded fashion, after a 4-minute training with 11 representative images. All imaged sites were biopsied and interpreted by an expert pathologist. Sensitivity of all endoscopists for identification of high-grade dysplasia or cancer was 0.90 (95% confidence interval [CI]: 0.88-0.92) and specificity was 0.82 (95% CI: 0.79-0.85). Positive and negative predictive values were 0.72 (95% CI: 0.68-0.77) and 0.94 (95% CI: 0.92-0.96), respectively. No significant differences in accuracy were observed between experts and novices (0.90 vs. 0.84). The kappa statistic for all raters was 0.56 (95% CI: 0.54-0.58), and the difference between groups was not significant (0.64 vs. 0.55). These data suggest that gastroenterologists can diagnose Barrett's-related neoplasia on HRME images with high sensitivity and specificity, without the aid of prior microendoscopy experience.

Ultra-high speed and ultra-high resolution spectral-domain optical coherence tomography and optical Doppler tomography in ophthalmology.

We present ultra-high resolution optical coherence tomography (OCT) structural intensity and optical Doppler tomography (ODT) flow velocity images of the human retina in vivo. The ultra-high speed OCT system is based on Spectral Domain or Fourier Domain technology, which provides a sensitivity advantage over conventional OCT of more than 2 orders of magnitude. This sensitivity improvement allows video rate OCT and ODT cross sectional imaging of retinal structures. Images will be presented with axial resolutions of 6 and 3.5 microns. We observed small features in the inner and outer plexiform layers, which are believed to be small blood vessels. Flow velocity images will be presented showing pulsatile flow in retinal arteries and veins.

Extended-Cavity Semiconductor Wavelength-Swept Laser for Biomedical Imaging.

We demonstrate a compact high-power rapidly swept wavelength tunable laser source based on a semiconductor optical amplifier and an extended-cavity grating filter. The laser produces excellent output characteristics for biomedical imaging, exhibiting >4-mW average output power, <0.06-nm instantaneous linewidth, and >80-dB noise extinction with its center wavelength swept over 100 nm at 1310 nm at variable repetition rates up to 500 Hz.

Computer simulation of stair falls to investigate scenarios in child abuse.

OBJECTIVES: To demonstrate the usefulness of computer simulation techniques in the investigation of pediatric stair falls. Since stair falls are a common falsely reported injury scenario in child abuse, our specific aim was to investigate the influence of stair characteristics on injury biomechanics of pediatric stair falls by using a computer simulation model. Our long-term goal is to use knowledge of biomechanics to aid in distinguishing between accidents and abuse. METHODS: A computer simulation model of a 3-year-old child falling down stairs was developed using commercially available simulation software. This model was used to investigate the influence that stair characteristics have on biomechanical measures associated with injury risk. Since femur fractures occur in unintentional and abuse scenarios, biomechanical measures were focused on the lower extremities. RESULTS: The number and slope of steps and stair surface friction and elasticity were found to affect biomechanical measures associated with injury risk. CONCLUSIONS: Computer simulation techniques are useful for investigating the biomechanics of stair falls. Using our simulation model, we determined that stair characteristics have an effect on potential for lower extremity injuries. Although absolute values of biomechanical measures should not be relied on in an unvalidated model such as this, relationships between accident-environment factors and biomechanical measures can be studied through simulation. Future efforts will focus on model validation.

Laser-tissue interaction with a continuous wave 3-mcm fibre laser: preliminary studies with soft tissue.

BACKGROUND AND OBJECTIVE: Lasers operating at wavelengths in the mid-infrared region have become increasingly popular for applications in areas of surgery and medicine. Advances in fibre laser technology have introduced a highly efficient, compact, diode-pumped source operating at around the 3-mcm wavelength. This study examines the effects of this recently developed laser on soft biological tissue. STUDY DESIGN/MATERIALS AND METHODS: Chicken breast and liver tissue samples were exposed to 800 mW continuous wave laser power, at a wavelength of 2.71 mcm, with incident spot sizes of around 150 mcm. Samples were inspected grossly immediately after laser irradiation and also prepared for histologic processing. RESULTS: After irradiation, visual assessment of changes at sample surfaces indicated a region of thermally affected tissue surrounding the ablation crater. This region was observed to grow in size to around 1.0 mm in diameter after 3 seconds of laser exposure at 800 mW. An ablation velocity of 0.80 mm.s(-1) was determined in chicken breast for the same incident laser parameters. Analysis of samples irradiated at 800 mW and processed for histology revealed minimal damage at hole boundaries and no signs of char formation, providing incident exposure times were restricted to below around 0. 5 seconds. CONCLUSION: This fibre laser source has demonstrated its potential to fulfil medical applications, enabling accurate, precise tissue removal to proceed at a rapid ablation rate. The efficiency and small size of the laser are attractive features.

Biomechanical evaluation of dual-energy X-ray absorptiometry for predicting fracture loads of the infant femur for injury investigation: an in vitro porcine model.

OBJECTIVE: The purpose of this study was to determine the ability of bone mineral density (BMD) measured by dual-energy x-ray absorptiometry (DXA) and geometry measured by biplanar x-ray to predict fracture mechanics in vitro in an immature femur model. DESIGN: Prospective analysis of radiographic and biomechanical data was performed. SETTING: In vitro experimentation. INTERVENTIONS: Bone geometry and DXA data were obtained before mechanical testing. Twenty-two porcine femora from males and females (age 3 to 12 months; body weight 3.6 to 7.0 kilograms) were fractured. Mechanical tests were performed on the diaphysis of the femora in two loading configurations: (a) three-point bending to simulate loads that result in transverse fractures; and (b) torsion to simulate twisting injuries that result in spiral fractures. MAIN OUTCOME MEASURES: Correlation of radiographic data with the experimentally determined bone strength. RESULTS: Three-point bending consistently resulted in transverse fractures. Femoral diaphysis BMD (mean, 0.304 grams per square centimeter; SD, 0.028 grams per square centimeter) strongly correlated (r2 = 0.938) to fracture load in bending. Load at failure ranged from 530 to 1,024 N (mean, 726 N; SD, 138 N), consistent with the findings of Miltner. Empirically derived strength parameters coupling BMD with geometry accurately predicted bending loads (r2 = 0.84, p < 0.001) and energy to failure (r2 = 0.88, p < 0.05). Torsional loading failed to generate spiral fractures consistently, resulting in either end plate or diaphyseal fractures. Load at failure for torsion ranged from 1,383 to 3,559 Newton-millimeters (mean, 2,703 Newton-millimeters; SD, 826 Newton-millimeters). Because of these inconsistent fracture results, empirical strength parameters for torsion could not be derived. CONCLUSION: BMD coupled with geometry is a strong predictor of bending fracture loads in the immature femoral diaphysis. A similar relationship could not be shown for torsion because of inconsistent failure results. This study represents an initial attempt at developing a methodology for predicting the strength of young bones from radiographic measures. Further research is required to establish this methodology and to show the necessary correlation with immature human bone.

Laser-tissue interaction with a high-power 2-microm fiber laser: preliminary studies with soft tissue.

BACKGROUND AND OBJECTIVE: Recent developments in fiber laser technology have introduced highly efficient, compact sources with high output beam quality. The first laser-tissue interaction studies with a high-power 2-microm fiber laser were conducted. STUDY DESIGN/MATERIALS AND METHODS: Chicken breast and porcine muscle tissue samples were subjected to continuous wave (cw) irradiation at 800-mW and 5-W output power levels, with spot sizes of approximately 150 microm. After laser irradiation, samples were inspected with an optical microscope and prepared for histologic processing. RESULTS: Evaluation of surface changes in tissue samples indicated an interaction similar in nature to those previously demonstrated with other cw lasers, but with photothermal ablation characteristics typical of strongly absorbed lasers operating in the infrared wavelength region. An ablation velocity of 0.27 mm.sec(-1) in porcine tissue was determined at 800-mW incident power. Histopathologic analysis demonstrated the formation of lesions with minimal damage at boundaries and no evidence of carbonization. CONCLUSIONS: Results indicate that this fiber laser has the potential to fulfill applications in the medical field.

Evaluation of ketorolac in children with forearm fractures.

OBJECTIVES: To evaluate ketorolac for pain relief and an opioid-sparing effect in children with forearm fractures necessitating reduction. METHODS: A prospective, randomized, double-blind study was conducted at an urban children's hospital ED. A convenience sample of children aged 3-18 years with isolated forearm fractures was studied. None received prior pain medication. A 10-point visual analog scale (VAS) was used to assess pain at the time of study entry and prior to sedation/analgesia. The Children's Hospital of Eastern Ontario's Pain Score (CHEOPS), a 13-point behavioral score, was used to assess pain during sedation. Patients received either IV ketorolac (K), 1 mg/kg, or saline (S) after entry into the study. After a minimum of 20 minutes, pain was reassessed and supplemental analgesia/sedation administered. A standard dose of midazolam, 0.1 mg/kg to a maximum of 6 mg, was given to all patients, and fentanyl was titrated at 1-microgram/kg increments based on patient need. Once the patient was comfortable, reduction was performed and a reduction CHEOPS score assigned. RESULTS: For the 34 study children (17 K, 17 S), there was no difference in sex or mean age between the groups. Mean total doses of fentanyl were 2.26 micrograms/kg in the K group and 2.85 micrograms/kg in the S group (p = 0.07). The median changes in VAS score before and after receiving the study drug were -1.13 K and -0.18 S (p = 0.06). The median CHEOPS score was 10 for both groups. Seven of the 17 patients in the S group required the maximum fentanyl dose (4 micrograms/kg), compared with 2 of 17 in the K group (p = p.06). CONCLUSIONS: Although ketorolac seems to add to patient comfort in children with forearm fractures, it does not have a significant opioid-sparing effect. Ketorolac showed a trend toward pain relief, but statistical significance was not reached.

Effects of hyperthermia and iodine-131-labeled anticarcinoembryonic antigen monoclonal antibody on human tumor xenografts in nude mice.

BACKGROUND: Many studies have demonstrated synergistic interaction between hyperthermia and radiation. This study was undertaken to determine whether hyperthermia could enhance the effect of radioimmunotherapy (RIT) in the treatment of human colon adenocarcinoma xenografts in nude mice. METHODS: The experiments were conducted in two parts. During the first part of the study, preliminary information was obtained regarding the effect of various temperatures (41 degrees C, 42 degrees C, and 43 degrees C for 45 minutes) and iodine-131-labeled anticarcinoembryonic antigen (CEA) monoclonal antibodies (RMoAb) with administered activity ranging from 130 +/- 19 microCi to 546 +/- 19 microCi on tumor regrowth delay (TRD) and volume doubling time. This information was used in Part 2 of the study, which included four groups of mice: (1) a control group, (2) a group treated with hyperthermia, (3) a group treated with RMoAb, and (4) a group treated with a combination of RMoAb and hyperthermia. RESULTS: Maximum and significantly increased TRD was observed in the group treated with RMoAb and hyperthermia (slope, 0.057) compared with the control group (slope, 0.322), the hyperthermia-treated group (slope, 0.302), and the group treated with RMoAb alone (slope, 0.098). The ratio of the slopes between the groups treated with RMoAb and those treated with RMoAb and hyperthermia was 1.72. No correlation was detected between the percent of antibody uptake in the tumor and tumor regression in the groups treated with heat and RMoAb and those treated with RMoAb alone. CONCLUSIONS: The results of these experiments show that hyperthermia increased the effectiveness of iodine-131-labeled anti-CEA monoclonal antibodies against human colon carcinoma xenografts in nude mice. This study offers a rationale for combining hyperthermia and low-dose radiation produced from RIT in clinical practice.

Evaluation of an ingestible telemetric temperature sensor for deep hyperthermia applications.

We have investigated the potential of an ingestible thermometric system (ITS) for use with a deep heating system. The ingestible sensor contains a temperature-sensitive quartz crystal oscillator. The telemetered signal is inductively coupled by a radiofrequency coil system to an external receiver. The sensors, covered with a protective silicon coating, are 10 mm in diameter and 20 mm long and are energized by an internal silver-oxide battery. Experimental studies were carried out to investigate the accuracy of the system and the extent of reliable operation of these sensors in an electromagnetic environment. Different measurements were repeated for five sensors. Calibration accuracy was verified by comparison with a Bowman probe in the temperature range 30 degrees C to 55 degrees C. Linear regression analysis of individual pill readings indicated a correlation within +/- 0.4 degrees C at 95% prediction intervals in the clinical temperature range of 35 degrees C to 50 degrees C. Further work is required to improve this accuracy to meet the quality assurance guidelines of +/- 0.2 degrees C suggested by the Hyperthermia Physics Center. Response times were determined by the exponential fit of heat-up and cool-down curves for each pill. All curves had correlation coefficients greater than 0.98. Time (mean +/- SE) to achieve 90% response during heat-up was 115 +/- sec. Time to cool-down to 10% of initial temperature was 114 +/- 4 sec. The effect of the external antenna and sensor spacing and the angle of orientation of the sensor relative to the antenna plane were also studied. Electromagnetic interference effects were studied by placing the sensor with a Bowman probe in a cylindrical saline phantom for the tests in an annular phase array applicator. Different power levels at three frequencies--80, 100, and 120 MHz--were used. Accurate temperature readings could not be obtained when the electromagnetic power was on because of interference effects with the receiver. However, the temperatures read with the ITS immediately after the electromagnetic power was switched off correlated well with the Bowman probe readings across the power categories and the three frequencies used. The phantom was heated to steady state, with a Bowman probe placed at the central axis of the cylinder used as control. During the heat-up period and the steady state, the mean difference (+/- SE) between the ITS and Bowman probe was 0.12 degrees C (+/- 0.05 degrees C).(ABSTRACT TRUNCATED AT 400 WORDS)