Deep Learning-Generated Synthetic MR Imaging STIR Spine Images Are Superior in Image Quality and Diagnostically Equivalent to Conventional STIR: A Multicenter, Multireader Trial.

BACKGROUND AND PURPOSE: Deep learning image reconstruction allows faster MR imaging acquisitions while matching or exceeding the standard of care and can create synthetic images from existing data sets. This multicenter, multireader spine study evaluated the performance of synthetically created STIR compared with acquired STIR. MATERIALS AND METHODS: From a multicenter, multiscanner data base of 328 clinical cases, a nonreader neuroradiologist randomly selected 110 spine MR imaging studies in 93 patients (sagittal T1, T2, and STIR) and classified them into 5 categories of disease and healthy. A DICOM-based deep learning application generated a synthetically created STIR series from the sagittal T1 and T2 images. Five radiologists (3 neuroradiologists, 1 musculoskeletal radiologist, and 1 general radiologist) rated the STIR quality and classified disease pathology (study 1, n = 80). They then assessed the presence or absence of findings typically evaluated with STIR in patients with trauma (study 2, n = 30). The readers evaluated studies with either acquired STIR or synthetically created STIR in a blinded and randomized fashion with a 1-month washout period. The interchangeability of acquired STIR and synthetically created STIR was assessed using a noninferiority threshold of 10%. RESULTS: For classification, there was a decrease in interreader agreement expected by randomly introducing synthetically created STIR of 3.23%. For trauma, there was an overall increase in interreader agreement by +1.9%. The lower bound of confidence for both exceeded the noninferiority threshold, indicating interchangeability of synthetically created STIR with acquired STIR. Both the Wilcoxon signed-rank and t tests showed higher image-quality scores for synthetically created STIR over acquired STIR (P < .0001). CONCLUSIONS: Synthetically created STIR spine MR images were diagnostically interchangeable with acquired STIR, while providing significantly higher image quality, suggesting routine clinical practice potential.

Desarrollo de capacidades para la renovación de la atención primaria de salud: gestión de la APS en el nuevo modelo de atención: desafíos de la gestión de los recursos humanos en salud

En la última clase del curso "Desarrollo de capacidades para la renovación de la atención primaria de salud", tiene un documento preparado por la Organización Mundial de la Salud sobre los retos de la gestión de recursos humanos en salud.

Tailored CT: primum non nocere.

Despite its vital diagnostic utility, the ionizing radiation used in CT is not benign. Patients have an increased risk of dying from a radiation-induced cancer for every pass through a CT scanner. One way to reduce this risk is to tailor CT, especially follow-up scans, to specific areas of concern. By doing so, we can help to minimize the small but real risk from this essential technology.

Test characteristics of the urine Gram stain in infants

OBJECTIVE: The utility of the Gram stain for the preliminary diagnosis of urinary tract infections (UTI) in infants or= 38.0 degrees C presenting to a pediatric emergency department during 2 consecutive winter seasons. Single pathogen growth of >or= 10(4) cfu/mL from a catheterized specimen and >or= 10(3) cfu/mL from a suprapubic specimen was considered positive. A positive Gram stain was defined as the identification of any organisms. Urinalysis was tested for the presence of nitrites and for leukocyte esterase (LE). Urine microscopy was analyzed for white blood cells per high power field (WBC/hpf). RESULTS: Fourteen of 246 patients were excluded; 11 because no Gram stain was completed. Of the remaining 232 patients, Gram stain had a sensitivity of 85.2% (95% CI 71.9-98.6%), a specificity of 99.0% (95% CI 97.7-100%), a likelihood ratio for a positive test of 87.3 (95% CI 21.8-349.9), and a likelihood ratio for a negative test of 0.15 (95% CI 0.06-0.37). There were 193 specimens for which a Gram stain and a complete UA and microscopy were completed and compared. Urine microscopy had a lower sensitivity and specificity than Gram stain for both >or= 5 WBC/hpf and >or= 10 WBC/hpf. In addition to the Gram stain, a dipstick negative for nitrites and LE had a low negative likelihood ratio (0.16), useful for decreasing the likelihood of a UTI. CONCLUSIONS: The Gram stain has excellent test characteristics for the preliminary diagnosis of a UTI in febrile infants. Patient disposition and therapy will likely change if clinical protocols and guidelines use the Gram stain rather than urine microscopy for preliminary diagnosis of UTI in infants.

Effects of release time and directionality on unilateral and bilateral hearing aid fittings in complex sound fields.

In studies to date, the effectiveness of the directional microphone has been investigated independently of the signal processing scheme used in the hearing aid. In addition, the number and placement of the background noise speakers can create an advantage for a particular polar pattern (i.e., cardioid, supercardioid, and hypercardioid) in any laboratory design. With these considerations in mind, the purpose of this investigation was twofold: (1) to determine the effect of different amplitude-compression release times on speech perception ability in noise, measured with directional microphone hearing aids, and (2) to determine the impact of environment (classroom vs anechoic chamber) on those measures. Ten subjects with mild to moderate sensorineural hearing loss participated. Using an eight-speaker complex sound field, speech perception was assessed in an anechoic chamber and a typical classroom environment. None of the release times resulted in superior performance in either the anechoic or classroom environment.

To burn or not to burn: use of computer-enhanced stimuli to encourage application of sunscreens.

Skin cancer affects 515,000 Americans every year, causing more than 7,000 deaths. Prior studies attempted, with scant success, to increase general knowledge about protection of the skin and to encourage use of sunscreens. The failure was attributed to the allure of the suntan as a symbol of health and affluence and to the "optimistic bias" (belief in one's own invulnerability) displayed by sunbathers. The study detailed here sought to increase the use by subjects of sunscreen by showing computer-altered images of their own faces, aged and disfigured by lesions. That stimulus was designed to counter false impressions and illusions of sunbathers about the benefits of the sun by demonstrating, immediately and personally, negative effects of sun exposure. Data were collected from thirty adolescents in the form of six weekly logs of sunscreen use and time spent outdoors between 10 AM and 3 PM. Results showed that the computer-altered images motivated increased use of sunscreen in the short term: subjects in the experimental groups used sunscreen almost three times as frequently as those in the control group during the experimental period (P = 0.000). Images of aging and disfiguring by lesions produced a more intense and prolonged modification in behavior than images of aging only.

Association of a V beta 2-specific superantigen with a tumorigenic milk-borne mouse mammary tumor virus.

A number of endogenous mouse mammary tumor virus (MMTV) proviruses encode superantigens that have the property of stimulating mature T lymphocytes in a TCR V beta-specific fashion and of mediating V beta-specific clonal deletion in developing T cells. The tumorigenic milk-borne MMTV carried by C3H and GR mice also have superantigen properties in vivo, and it has been proposed that this superantigenic function is critical to the infectivity and/or tumorigenicity of the virus. To test the requirement for superantigen properties in tumorigenic MMTV, a highly tumorigenic strain of MMTV isolated from BALB/c mice (BALB/cV virus) was analyzed for its effect on TCR V beta expression. It was found that exposure of newborn mice to milk-borne virus results in marked deletion of V beta 2-expressing CD4+ peripheral T cells. This deletion is detected in mature TCRhigh thymocytes as well as in peripheral T cells from virus-exposed mice. Deletion is dependent on expression of a permissive MHC type in mice exposed to virus. Subcutaneous injection of adult mice with virus-containing milk induces a substantial increase in V beta 2+ CD4+ cells in draining lymph nodes within 4 days. Thus, tumorigenic BALB/cV is associated with V beta 2-specific superantigen activity capable of mediating both T cell expansion and clonal deletion in vivo. These findings are consistent with a critical role of superantigen-mediated T cell activation in MMTV infection and tumorigenesis.