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1.
Dig Dis ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38663364

RESUMEN

BACKGROUND: The use of endoscopic ultrasound-guided (EUS) transmural stent placement for pancreatic walled-off-necrosis (WON) drainage is widespread. This study retrospectively analyzes imaging parameters predicting the outcomes of WON endoscopic drainage using lumen apposing metal stents (LAMS). METHODS: The study analyzed data of 115 patients who underwent EUS-guided debridement using LAMS from 2011 to 2015. Pre-intervention CT or MRI were used to analyze WON total volume, percentage of debris, multilocularity, and density. Success measures included technical success, the number of endoscopic sessions, requirement of percutaneous drainage, long-term success, and recurrence. RESULTS: The primary cause of pancreatitis was gallstones (50.4%), followed by alcohol (27.8%), hypertriglyceridemia (11.3%), idiopathic (8.7%), and autoimmune (1.7%). The mean WON size was 674 mL. All patients underwent endoscopic necrosectomies, averaging 3.1 sessions. Stent placement was successful in 96.5% of cases. Procedural complications were observed in 13 patients (11.3%) and six patients (5.2%) needed additional percutaneous drainage. No patients reported recurrent WON post-treatment. Univariate analysis indicated a significant correlation between debris percentage and the need for additional drainage and long-term success (p <0.001). The number of endoscopic sessions correlated significantly with debris percentage (p < 0.001). CONCLUSIONS: Preprocedural imaging, particularly debris percentage within WON, significantly predicts the number of endoscopic sessions, the need for further percutaneous drainage, and overall long-term success.

2.
Phys Rev Lett ; 132(13): 131004, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613261

RESUMEN

We present first results from a dark photon dark matter search in the mass range from 44 to 52 µeV (10.7-12.5 GHz) using a room-temperature dish antenna setup called GigaBREAD. Dark photon dark matter converts to ordinary photons on a cylindrical metallic emission surface with area 0.5 m^{2} and is focused by a novel parabolic reflector onto a horn antenna. Signals are read out with a low-noise receiver system. A first data taking run with 24 days of data does not show evidence for dark photon dark matter in this mass range, excluding dark photon photon mixing parameters χ≳10^{-12} in this range at 90% confidence level. This surpasses existing constraints by about 2 orders of magnitude and is the most stringent bound on dark photons in this range below 49 µeV.

3.
Space Sci Rev ; 219(8): 80, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38037569

RESUMEN

The Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE) on both the Van Allen Probes spacecraft is a time-of-flight versus total energy instrument that provided ion composition data over the ring current energy (∼7 keV to ∼1 MeV), and electrons over the energy range ∼25 keV to ∼1 MeV throughout the duration of the mission (2012 - 2019). In this paper we present instrument calibrations, implemented after the Van Allen Probes mission was launched. In particular, we discuss updated rate dependent corrections, possible contamination by "accidentals" rates, and caveats concerning the use of certain products. We also provide a summary of the major advances in ring current science, obtained from RBSPICE observations, and their implications for the future of inner magnetosphere exploration.

4.
J Clin Exp Hepatol ; 13(6): 955-961, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37975040

RESUMEN

Background/Aims: Nonalcoholic fatty liver disease (NAFLD) has been observed in patients after partial pancreatectomy. Previous studies have been performed on oncologic patients who underwent partial pancreatectomy and received adjuvant chemotherapy. By studying a cohort of patients with intraductal papillary mucinous neoplasms (IPMNs) who did not receive chemotherapy, the authors investigate the isolated effect of partial pancreatectomy on the development of fatty liver. Methods: A retrospective search for patients with pancreatic IPMNs who underwent partial pancreatectomy at an academic center from 2006 to 2014 identified 63 patients, including 42 who had pancreaticoduodenectomy (PD) and 21 who had distal pancreatectomy (DP). Fourteen patients with preoperative hepatic steatosis, diabetes, obesity, on steroid therapy, history of malignancy, or incomplete data were excluded. No patient received chemotherapy. Liver fat signal fraction (LFSF) was computed by the Dixon method using pre- and postoperative in- and out-of-phase MRI. Results: Of the 49 patients included in the study, 29 (59%) underwent PD and 20 (41%) underwent DP. A total of 17 patients (34%) developed fatty liver after surgery. The entire cohort developed significant weight loss, 72.1 versus 69.4 kg (P < 0.01). Postoperatively, there was significant increase in LFSF, 1.3% versus 9.6% following PD (P < 0.01), and 2.1% versus 9.4% following DP (P = 0.01). Conclusion: Partial pancreatectomy increases the risk of NAFLD independent of chemotherapy-induced hepatotoxicity. The underlying mechanism remains unclear and possibly related to pancreatic exocrine insufficiency and malnutrition.

5.
J Clin Transl Hepatol ; 11(3): 534-539, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-36969887

RESUMEN

Background and Aims: Distinguishing alcoholic steatohepatitis (ASH) and nonalcoholic steatohepatitis (NASH) with biopsy alone is often difficult without a reliable clinical context. A novel finding on liver imaging, perivascular branching heterogeneity, has shown promise in distinguishing between these chronic liver diseases. Our study investigated the role of this finding on imaging to differentiate between ASH and NASH. The aim of this study was to determine the utility and reproducibility of this novel radiographic marker to help distinguish ASH from NASH. Methods: This was a retrospective cohort study conducted between 2016 and 2020 in patients with both liver biopsy-confirmed steatohepatitis/chronic hepatitis and abdominal magnetic resonance imaging within 13 months of each other. Two radiologists, blinded to patient clinical history and diagnosis, categorized the appearance of the liver as: 1- homogeneity, 2- mild heterogeneity, 3- moderate heterogeneity, 4- possible perivascular branching, 5- definite perivascular branching. Results: Of the 90 patients in the study, 60 were identified as NASH and 30 as ASH. The area under the curve (AUC) for both reader 1 and 2 when using the 5-point scale was 0.69 (CI: 0.56-0.82, p=0.006) and 0.72 (CI: 0.60-0.85, p=0.001), respectively. The positive predictive value (PPV) for identification of ASH when scoring 5 was 64.7% and 66.7% for reader 1 and 2, respectively. Interclass correlation coefficient was 0.74 in patients with ASH, indicating moderate reliability among both readers. Conclusions: Identification of this perivascular branching pattern on imaging is a promising novel diagnostic marker that can be used with other methods to help distinguish between ASH and NASH.

6.
J Magn Reson Imaging ; 58(4): 1191-1197, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36744579

RESUMEN

BACKGROUND: Focal nodular hyperplasia (FNH) and hepatic adenoma (HA) are two common benign liver lesions with different management options. In particular, resection is considered for large HA lesions to avoid possible bleeding complications or rarely malignant degeneration. PURPOSE: To determine whether early enhancement of a draining hepatic vein (EDHV) and absence of perilesional enhancement (PLE) on arterial phase MR images are useful for distinguishing FNH from HA. STUDY TYPE: Retrospective. POPULATION: A total of 34 patients: 16 with FNH and 18 with HA lesions. FIELD STRENGTH/SEQUENCE: A1.5 T, axial T1 fat-suppressed arterial postcontrast. ASSESMENT: Four abdominal radiologists blinded to pathologic diagnosis assessed for the presence or absence of EDHV in association with the lesion, definitively characterized by pathology. This was considered present if contrast could be identified in a hepatic vein contiguous with the lesion in question. Secondarily, PLE was evaluated. STATISTICAL TESTS: Fleiss's multirater kappa statistic, Chi-squared statistic, Phi-coefficient. Significance level P < 0.05. RESULTS: Considering all observations obtained from the four readers, an EDHV was identified with FNH 48.5% of the time. EDHV was seen with HA in 8.8% of cases. PLE was seen with significantly greater frequency in HA. The presence of an EDHV was associated with the absence of PLE. DATA CONCLUSION: In a lesion that may be either an FNH or HA, confident identification on arterial phase images of an EDHV should lead the reader to favor FNH, while the presence PLE should dissuade the reader from FNH. EVIDENCE LEVEL: 4. TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Adenoma de Células Hepáticas , Hiperplasia Nodular Focal , Neoplasias Hepáticas , Humanos , Hiperplasia Nodular Focal/diagnóstico por imagen , Hiperplasia Nodular Focal/patología , Neoplasias Hepáticas/patología , Estudios Retrospectivos , Venas Hepáticas , Medios de Contraste , Adenoma de Células Hepáticas/diagnóstico por imagen , Hígado/diagnóstico por imagen , Hígado/patología , Imagen por Resonancia Magnética/métodos , Diagnóstico Diferencial
7.
Radiology ; 307(1): e222801, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36853182

RESUMEN

Since its initial release in 2011, the Liver Imaging Reporting and Data System (LI-RADS) has evolved and expanded in scope. It started as a single algorithm for hepatocellular carcinoma (HCC) diagnosis with CT or MRI with extracellular contrast agents and has grown into a multialgorithm network covering all major liver imaging modalities and contexts of use. Furthermore, it has developed its own lexicon, report templates, and supplementary materials. This article highlights the major achievements of LI-RADS in the past 11 years, including adoption in clinical care and research across the globe, and complete unification of HCC diagnostic systems in the United States. Additionally, the authors discuss current gaps in knowledge, which include challenges in surveillance, diagnostic population definition, perceived complexity, limited sensitivity of LR-5 (definite HCC) category, management implications of indeterminate observations, challenges in reporting, and treatment response assessment following radiation-based therapies and systemic treatments. Finally, the authors discuss future directions, which will focus on mitigating the current challenges and incorporating advanced technologies. Tha authors envision that LI-RADS will ultimately transform into a probability-based system for diagnosis and prognostication of liver cancers that will integrate patient characteristics and quantitative imaging features, while accounting for imaging modality and contrast agent.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Estudios Retrospectivos , Sensibilidad y Especificidad
8.
Space Sci Rev ; 218(8): 66, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36407497

RESUMEN

The Van Allen Probes mission operations materialized through a distributed model in which operational responsibility was divided between the Mission Operations Center (MOC) and separate instrument specific SOCs. The sole MOC handled all aspects of telemetering and receiving tasks as well as certain scientifically relevant ancillary tasks. Each instrument science team developed individual instrument specific SOCs proficient in unique capabilities in support of science data acquisition, data processing, instrument performance, and tools for the instrument team scientists. In parallel activities, project scientists took on the task of providing a significant modeling tool base usable by the instrument science teams and the larger scientific community. With a mission as complex as Van Allen Probes, scientific inquiry occurred due to constant and significant collaboration between the SOCs and in concert with the project science team. Planned cross-instrument coordinated observations resulted in critical discoveries during the seven-year mission. Instrument cross-calibration activities elucidated a more seamless set of data products. Specific topics include post-launch changes and enhancements to the SOCs, discussion of coordination activities between the SOCs, SOC specific analysis software, modeling software provided by the Van Allen Probes project, and a section on lessons learned. One of the most significant lessons learned was the importance of the original decision to implement individual team SOCs providing timely and well-documented instrument data for the NASA Van Allen Probes Mission scientists and the larger magnetospheric and radiation belt scientific community.

9.
Annu Rev Vis Sci ; 8: 291-321, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-35385674

RESUMEN

For four decades, investigations of the biological basis of critical periods in the developing mammalian visual cortex were dominated by study of the consequences of altered early visual experience in cats and nonhuman primates. The neural deficits thus revealed also provided insight into the origin and neural basis of human amblyopia that in turn motivated additional studies of humans with abnormal early visual input. Recent human studies point to deficits arising from alterations in all visual cortical areas and even in nonvisual cortical regions. As the new human data accumulated in parallel with a near-complete shift toward the use of rodent animal models for the study of neural mechanisms, it is now essential to review the human data and the earlier animal data obtained from cats and monkeys to infer general conclusions and to optimize future choice of the most appropriate animal model.


Asunto(s)
Ambliopía , Corteza Visual , Animales , Gatos , Modelos Animales de Enfermedad , Humanos , Mamíferos , Visión Ocular
10.
Radiographics ; 42(1): 125-142, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34797734

RESUMEN

Liver blood tests (often also known as liver chemistries, liver tests, or the common misnomer liver function tests) are routinely used in diagnosis and management of hepatobiliary disease. Abnormal liver blood test results are often the first indicator of hepatobiliary disease and a common indication for abdominal imaging with US, CT, or MRI. Most of the disease entities can be categorized into hepatocellular or cholestatic patterns, with characteristic traits on liver blood tests. Each pattern has a specific differential, which can help narrow the differential diagnosis when combined with the clinical history and imaging findings. This article reviews the major liver blood tests as well as a general approach to recognizing common patterns of hepatobiliary disease within these tests (hepatocellular, cholestatic, acute liver failure, isolated hyperbilirubinemia). Examples of hepatobiliary disease with hepatocellular or cholestatic patterns are presented with characteristic test abnormalities and imaging findings. The commonly encountered scenario of chronic hepatitis with possible fibrosis is also reviewed, with discussion of potential further imaging such as elastography. The role of liver blood tests and imaging in evaluating complications of hepatic transplant is also discussed. Overall, integrating liver blood test patterns with imaging findings can help the radiologist accurately diagnose hepatobiliary disease, especially in cases where imaging findings may not allow differentiation between different entities. ©RSNA, 2021.


Asunto(s)
Hígado , Imagen por Resonancia Magnética , Pruebas Hematológicas , Humanos , Hígado/diagnóstico por imagen , Pruebas de Función Hepática , Imagen por Resonancia Magnética/métodos , Radiólogos
11.
Front Neurosci ; 15: 781516, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34955729

RESUMEN

A new procedure was used to study the development of gaze (responses to moving targets or laser spots in normal kittens, those that had been reared in total darkness to 6 weeks of age, and others that received a period of monocular deprivation (MD). Gaze responses were observed to all stimuli in normal kittens at between 25-30 days of age and striking responses occurred on the same day or the next. Despite slow acquisition of spatial vision in the dark reared kittens over 3 months, they were able to follow and even strike at moving visual stimuli within a day of their initial exposure to light. By contrast, for a week following a period of MD, kittens showed no gaze or striking responses to moving stimuli when using their previously deprived eye. The very different profiles of acquisition of visuomotor skills and spatial vision in visually deprived kittens point to a dissociation between the neuronal populations that support these functions.

12.
Abdom Radiol (NY) ; 46(2): 562-569, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32743690

RESUMEN

PURPOSE: To assess the effect of gadobenate dimeglumine on magnetic resonance cholangiopancreatography (MRCP) and determine an appropriate time frame for performing MRCP sequences. MATERIALS AND METHODS: 2D MRCP sequences obtained after intravenous administration of gadobenate dimeglumine or gadobutrol over 14 months were reviewed retrospectively in randomized order by five abdominal radiologists, using a 3-point scale to rate biliary and pancreatic duct clarity (1 = no-, 2 = limited-, 3 = good visualization). Intraclass correlation coefficients were computed and mean scores were compared for both agents. For gadobenate dimeglumine exams, time delays between arterial phase and MRCP acquisition times were analyzed concerning duct clarity. For gadobutrol, only exams with delays ≥ 15 min were included. RESULTS: 134 exams (107 gadobenate dimeglumine, 27 gadobutrol) were included. Moderate reliability for pancreatic duct visualization and excellent reliability for visualization of intrahepatic bile ducts and upper and lower extrahepatic bile ducts were noted. No difference in mean scores was noted for pancreatic duct visualization (p = 0.66). Bile duct segment scores were lower with gadobenate dimeglumine (mean: 2.1-2.6) compared with gadobutrol (mean: 2.8-2.9) (p ≤ 0.006). For gadobenate dimeglumine, visualization scores varied depending on the delay between the arterial phase and MRCP acquisition (p ≤ 0.047). Good visualization for all bile duct segments was noted with delays of 7.2-9.4 min (95% confidence interval; mean 8.3 min). CONCLUSION: Bile duct clarity degraded on MRCP images with an increasing delay following gadobenate dimeglumine injection. 2D MRCP, thus, should be performed within 7.2 min after obtaining the arterial phase sequence to ensure good visualization of the entire biliary system.


Asunto(s)
Pancreatocolangiografía por Resonancia Magnética , Eliminación Hepatobiliar , Medios de Contraste , Humanos , Imagen por Resonancia Magnética , Meglumina/análogos & derivados , Compuestos Organometálicos , Reproducibilidad de los Resultados , Estudios Retrospectivos
13.
Hepatol Int ; 14(1): 70-79, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31802388

RESUMEN

PURPOSE: We compared the diagnostic performances of the European Association for the Study of the Liver (EASL) 2018 and Liver Imaging Reporting and Data System (LI-RADS) 2018 criteria on magnetic resonance imaging (MRI) for the noninvasive diagnosis of hepatocellular carcinoma (HCC) in high-risk patients and evaluated the difference in diagnostic value between MRI with extracellular contrast agents (ECA-MRI) and MRI with hepatobiliary agents (HBA-MRI). METHODS: This study included 382 observations from 298 patients at high risk for HCC who underwent preoperative multiphasic contrast-enhanced MRI between January 2015 and December 2016. Two readers assessed all observations according to the EASL 2018 and LI-RADS 2018 criteria, and the per-observation diagnostic performances were compared. RESULTS: On ECA-MRI, the LR-5 category of LI-RADS 2018 showed significantly higher sensitivity (78.9% vs. 71.5%, p = 0.005) and accuracy (81.7% vs. 75.0%, p = 0.003) for the diagnosis of HCC than the EASL 2018. On HBA-MRI, the diagnostic performances of the EASL 2018 and LR-5 of LI-RADS 2018 were not significantly different. When using EASL 2018, no statistically significant differences were observed in the diagnostic performances between ECA-MRI and HBA-MRI; however, when using the LR-5 of LI-RADS 2018, ECA-MRI had a higher sensitivity (78.9% vs. 67.5%, p = 0.029) than HBA-MRI. CONCLUSIONS: On ECA-MRI, the LR-5 category of LI-RADS 2018 provides better sensitivity and accuracy than the EASL 2018 for diagnosing HCC. EASL 2018 provides comparable diagnostic performances between ECA-MRI and HBA-MRI, but the LR-5 category of LI-RADS 2018 provides better sensitivity on ECA-MRI than on HBA-MRI.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Registros Electrónicos de Salud , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad
14.
Neural Plast ; 2019: 3198285, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31565047

RESUMEN

The capacity for neural plasticity in the mammalian central visual system adheres to a temporal profile in which plasticity peaks early in postnatal development and then declines to reach enduring negligible levels. Early studies to delineate the critical period in cats employed a fixed duration of monocular deprivation to measure the extent of ocular dominance changes induced at different ages. The largest deprivation effects were observed at about 4 weeks postnatal, with a steady decline in plasticity thereafter so that by about 16 weeks only small changes were measured. The capacity for plasticity is regulated by a changing landscape of molecules in the visual system across the lifespan. Studies in rodents and cats have demonstrated that the critical period can be altered by environmental or pharmacological manipulations that enhance plasticity at ages when it would normally be low. Immersion in complete darkness for long durations (dark rearing) has long been known to alter plasticity capacity by modifying plasticity-related molecules and slowing progress of the critical period. In this study, we investigated the possibility that brief darkness (dark exposure) imposed just prior to the critical period peak can enhance the level of plasticity beyond that observed naturally. We examined the level of plasticity by measuring two sensitive markers of monocular deprivation, namely, soma size of neurons and neurofilament labeling within the dorsal lateral geniculate nucleus. Significantly larger modification of soma size, but not neurofilament labeling, was observed at the critical period peak when dark exposure preceded monocular deprivation. This indicated that the natural plasticity ceiling is modifiable and also that brief darkness does not simply slow progress of the critical period. As an antecedent to traditional amblyopia treatment, darkness may increase treatment efficacy even at ages when plasticity is at its highest.


Asunto(s)
Predominio Ocular/fisiología , Cuerpos Geniculados/fisiología , Plasticidad Neuronal/fisiología , Vías Visuales/fisiología , Animales , Animales Recién Nacidos , Gatos , Período Crítico Psicológico , Oscuridad , Neuronas/fisiología , Privación Sensorial/fisiología , Corteza Visual/fisiología
15.
Radiographics ; 39(7): 1983-2002, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31626569

RESUMEN

Liver MR elastography is an imaging technique used to measure liver stiffness in the evaluation for possible fibrosis or cirrhosis. Liver stiffness measurement (LSM) is useful for predicting the stage of liver fibrosis. However, obtaining and reporting accurate and reliable LSMs with MR elastography require an understanding of the three core components of liver MR elastography: optimization of imaging technique, prompt quality control of images, and proper interpretation and reporting of elastogram findings. When performing MR elastography, six important technical parameters that should be optimized are patient fasting before the examination, proper passive driver placement, proper MR elastography section positioning over the largest area of the liver, use of MR elastography-related sequences at end expiration, choosing the best timing of the MR elastography sequence, and optimization of several essential pulse sequence parameters. As soon as the MR elastography examination is performed, the elastograms should be reviewed to ensure that they are of diagnostic quality so that corrective steps can be taken, if needed, and MR elastography can be repeated before the diagnostic portion of the examination concludes. Finally, the interpreting radiologist needs to understand and be able to perform the proper technique for LSMs, including determining which areas of the liver to include or avoid in the measurements; knowing which conditions, other than fibrosis or cirrhosis, can increase liver stiffness; and understanding how to report elastography results. This article reviews the proper technique for performing liver MR elastography and subsequent quality control assessment, as well as the principles for interpreting and reporting studies. This review may be helpful for implementing and operating a clinical liver MR elastography service.Online supplemental material is available for this article.©RSNA, 2019.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Interpretación de Imagen Asistida por Computador , Cirrosis Hepática/diagnóstico por imagen , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Artefactos , Lista de Verificación , Medios de Contraste , Elasticidad , Diseño de Equipo , Control de Formularios y Registros , Gadolinio , Humanos , Cirrosis Hepática/patología , Posicionamiento del Paciente , Control de Calidad , Respiración
16.
Neural Plast ; 2019: 7624837, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31178904

RESUMEN

Recent studies conducted on kittens have revealed that the reduced visual acuity of the deprived eye following a short period of monocular deprivation imposed in early life is reversed quickly following a 10-day period spent in total darkness. This study explored the contribution of the fellow eye to the darkness-induced recovery of the acuity of the deprived eye. Upon emergence of kittens from darkness, the fellow eye was occluded for different lengths of time in order to investigate its effects on either the speed or the extent of the recovery of acuity of the deprived eye. Occlusion of the fellow eye for even a day immediately following the period spent in darkness blocked any recovery of the acuity of the deprived eye. Moreover, occlusion of the fellow eye two days after the period of darkness blocked any further visual recovery beyond that achieved in the short period when both eyes were open. The results imply that the darkness-induced recovery of the acuity of the deprived eye depends upon, and is guided by, neural activity in the mature neural connections previously established by the fellow eye.


Asunto(s)
Ambliopía/fisiopatología , Fenómenos Fisiológicos Oculares , Privación Sensorial/fisiología , Visión Ocular/fisiología , Animales , Gatos , Oscuridad , Ojo
17.
J Vis ; 19(6): 25, 2019 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-31251809

RESUMEN

Exposure of kittens to complete darkness for 10 days has been shown (Duffy & Mitchell, 2013) to reverse the loss of visual acuity that follows a prior period of monocular deprivation (MD). In that study, recovery of acuity in the previously deprived eye was fast despite the fact that darkness was imposed 2 months after the period of MD when kittens were 3 months old. In a later study (Holman, Duffy, & Mitchell, 2018), it was demonstrated that the same period of darkness was ineffective when it was imposed on cats about 1 year old, suggesting that dark exposure may only promote recovery when applied within an early critical period. To determine the profile of this critical period, the identical period of darkness (10 days) was imposed on kittens at various ages that had all received the same 7-day period of MD from postnatal day 30 (P30). Recovery of the acuity of the deprived eye as measured by use of a jumping stand was complete when darkness was imposed prior to P186 days, but thereafter, darkness induced progressively smaller acuity improvements and was ineffective in kittens when it began at or beyond P191 days of age. These data indicate a critical period for darkness-induced recovery with an abrupt end over a 5-day period.


Asunto(s)
Ambliopía/fisiopatología , Adaptación a la Oscuridad/fisiología , Recuperación de la Función , Visión Monocular/fisiología , Agudeza Visual , Ambliopía/terapia , Animales , Gatos , Modelos Animales de Enfermedad , Estudios de Seguimiento , Privación Sensorial
18.
Ther Adv Urol ; 11: 1756287219842485, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31065294

RESUMEN

OBJECTIVES: The objective of this study was to determine if spatial distribution of multiparametric magnetic resonance imaging-transrectal ultrasound (mpMRI-TRUS) fusion biopsy cores to the index lesion reveals trends in the detection of intra-lesion Gleason heterogeneity and a more optimal prostate biopsy strategy. METHODS: Index lesion was the lesion with longest diameter on T2-weighted (T2W)-MRI. In cohort 1, fusion biopsy cores biopsies were taken in areas in the center of the target as well as 1 cm laterally on each side. For cohort 2, targeted biopsies were taken from the center of the lesion only. Heterogeneity was defined as difference in maximum Gleason score obtained from fusion cores in the center of the index lesion versus cores obtained from the periphery (cohort 1), or any difference in maximum Gleason score obtained from fusion cores targeted to the index lesion (cohort 2) compared with systematic 12 cores TRUS biopsy. RESULTS: Ninety-nine consecutive patients (35 and 64 in cohorts 1 and 2, respectively) with median age (SD) and prostate-specific antigen (PSA) of 66.9 (±5.9) and 9.7 (±8.2) respectively, were included. Age, PSA, Prostate Imaging Reporting and Data System (PI-RADS) score, and preoperative MRI lesion size were not significantly different between cohorts. Gleason heterogeneity was observed at a significantly higher rate in cohort 1 versus cohort 2 (58% versus 24%; p = 0.041). In cohort 1, cores obtained from the center of the lesion had higher Gleason score than cores obtained from the periphery of the targeted lesion in 57% of cases. CONCLUSIONS: We demonstrate that there is observable tumor heterogeneity in biopsy specimens, and that increased number of cores, as well as cores focused on the center and periphery of the largest lesion in the prostate, provide more comprehensive diagnostic information about the patient's clinical risk category than taking nonspecific cores targeted within the tumor.

20.
J Hepatocell Carcinoma ; 6: 49-69, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30788336

RESUMEN

The Liver Imaging Reporting and Data System (LI-RADS®) is a comprehensive system for standardizing the terminology, technique, interpretation, reporting, and data collection of liver observations in individuals at high risk for hepatocellular carcinoma (HCC). LI-RADS is supported and endorsed by the American College of Radiology (ACR). Upon its initial release in 2011, LI-RADS applied only to liver observations identified at CT or MRI. It has since been refined and expanded over multiple updates to now also address ultrasound-based surveillance, contrast-enhanced ultrasound for HCC diagnosis, and CT/MRI for assessing treatment response after locoregional therapy. The LI-RADS 2018 version was integrated into the HCC diagnosis, staging, and management practice guidance of the American Association for the Study of Liver Diseases (AASLD). This article reviews the major LI-RADS updates since its 2011 inception and provides an overview of the currently published LI-RADS algorithms.

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