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1.
Case Reports Hepatol ; 2024: 5112461, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38826497

RESUMEN

Drug-induced liver injury resulting from herbal and dietary supplement use is increasingly common and underrecognized. We report a case of a 34-year-old male recreational bodybuilder who presented with muscle cramping, fatigue, and diffuse itching in the setting of bodybuilding supplement use. Labs showed cholestatic liver injury, and liver biopsy revealed bland cholestasis and sinusoidal dilation. He was diagnosed with anabolic-androgenic steroid-induced liver injury. He was symptomatically managed with plasmapheresis for debilitating pruritus. This case highlights drug-induced liver injury as a complication of bodybuilding supplement use containing unlabeled anabolic-androgenic steroids. Sports medicine providers should inquire on herbal and dietary supplement use and be aware of potential contaminants.

2.
Eur Radiol ; 33(1): 535-544, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35864349

RESUMEN

OBJECTIVE: Liver lesion characterization is limited by the lack of an established gold standard for precise correlation of radiologic characteristics with their histologic features. The objective of this study was to demonstrate the feasibility of using an ex vivo MRI-compatible sectioning device for radiologic-pathologic co-localization of lesions in resected liver specimens. METHODS: In this prospective feasibility study, adults undergoing curative partial hepatectomy from February 2018 to January 2019 were enrolled. Gadoxetic acid was administered intraoperatively prior to hepatic vascular inflow ligation. Liver specimens were stabilized in an MRI-compatible acrylic lesion localization device (27 × 14 × 14 cm3) featuring slicing channels and a silicone gel 3D matrix. High-resolution 3D T1-weighted fast spoiled gradient echo and 3D T2-weighted fast-spin-echo images were acquired using a single channel quadrature head coil. Radiologic lesion coordinates guided pathologic sectioning. A final histopathologic diagnosis was prepared for all lesions. The proportion of successfully co-localized lesions was determined. RESULTS: A total of 57 lesions were identified radiologically and sectioned in liver specimens from 10 participants with liver metastases (n = 8), primary biliary mucinous cystic neoplasm (n = 1), and hepatic adenomatosis (n = 1). Of these, 38 lesions (67%) were < 1 cm. Overall, 52/57 (91%) of radiologically identified lesions were identified pathologically using the device. Of these, 5 lesions (10%) were not initially identified on gross examination but were confirmed histologically using MRI-guided localization. One lesion was identified grossly but not on MRI. CONCLUSIONS: We successfully demonstrated the feasibility of a clinical method for image-guided co-localization and histological characterization of liver lesions using an ex vivo MRI-compatible sectioning device. KEY POINTS: • The ex vivo MRI-compatible sectioning device provides a reliable method for radiologic-pathologic correlation of small (< 1 cm) liver lesions in human liver specimens. • The sectioning method can be feasibly implemented within a clinical practice setting and used in future efforts to study liver lesion characterization. • Intraoperative administration of gadoxetic acid results in enhancement in ex vivo MRI images of liver specimens hours later with excellent image quality.


Asunto(s)
Quistes , Neoplasias Hepáticas , Adulto , Humanos , Medios de Contraste/farmacología , Estudios Prospectivos , Gadolinio DTPA , Hígado/diagnóstico por imagen , Hígado/cirugía , Hígado/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética/métodos , Quistes/patología
3.
Case Rep Gastrointest Med ; 2020: 8418905, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32082652

RESUMEN

Gastrointestinal stromal tumors (GISTs) typically develop in the stomach or small intestine and rarely involve the ampulla of Vater, with only 13 cases reported in the world literature since 2004. Most authors advocate performing pancreaticoduodenectomy for such lesions. However, this operation can carry higher rates of morbidity and mortality compared to local resection. We present a case of a high-risk, invasive periampullary GIST and the multidisciplinary management approach to local resection with the aid of endoscopic ultrasound. In addition, this case shows no local recurrence at 3 months and a favorable clinical outcome at 1 year.

4.
Abdom Radiol (NY) ; 45(3): 661-671, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31781899

RESUMEN

PURPOSE: MRI proton density fat fraction (PDFF) can be calculated using magnitude (MRI-M) or complex (MRI-C) MRI data. The purpose of this study was to identify, assess, and compare the accuracy of common PDFF thresholds for MRI-M and MRI-C for assessing hepatic steatosis in patients with obesity, using histology as reference. METHODS: This two-center prospective study included patients undergoing MRI-C- and MRI-M-PDFF estimations within 3 days before weight loss surgery. Liver biopsy was performed, and histology-determined steatosis grades were used as reference standard. Using receiver operating characteristics (ROC) analysis on data pooled from both methods, single common thresholds for diagnosing and differentiating none or mild (0-1) from moderate to severe steatosis (2-3) were selected as the ones achieving the highest sensitivity while providing at least 90% specificity. Selection methods were cross-validated. Performances were compared using McNemar's tests. RESULTS: Of 81 included patients, 54 (67%) had steatosis. The common PDFF threshold for diagnosing steatosis was 5.4%, which provided a cross-validated 0.88 (95% CI 0.77-0.95) sensitivity and 0.92 (0.75-0.99) specificity for MRI-M and 0.87 sensitivity (0.75-0.94) with 0.81 (0.61-0.93) specificity for MRI-C. The common PDFF threshold to differentiate steatosis grades 0-1 from 2 to 3 was 14.7%, which provided cross-validated 0.86 (95% CI 0.59-0.98) sensitivity and 0.95 (0.87-0.99) specificity for MRI-M and 0.93 sensitivity (0.68-0.99) with 0.97(0.89-0.99) specificity for MRI-C. CONCLUSION: If independently validated, diagnostic thresholds of 5.4% and 14.7% could be adopted for both techniques for detecting and differentiating none to mild from moderate to severe steatosis, respectively, with high diagnostic accuracy.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Obesidad/complicaciones , Adulto , Anciano , Biopsia , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/patología , Estudios Prospectivos , Protones , Sensibilidad y Especificidad
5.
Pediatr Hematol Oncol ; 36(7): 451-456, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31424295

RESUMEN

Hemophagocytic lymphohistiocytosis (HLH) is a potentially fatal illness characterized by impaired natural killer (NK) cell and cytotoxic T-cell function. Patients develop systemic inflammation, multisystem organ dysfunction, and if untreated, death. Patients who present in the neonatal period often have atypical presentations with evidence of liver dysfunction and cholestasis; this has a broad differential diagnosis including neonatal infection, congenital liver defects, or other causes of liver dysfunction, such as neonatal hemochromatosis. Here, we present an infant whose diagnosis of familial HLH was confounded by the history of a stillborn sibling with suspected neonatal hemochromatosis, ultimately delaying diagnosis and initiation of curative treatment. This highlights the need to maintain a low threshold for sending HLH work-up concurrently with evaluation of liver diseases in infants with liver dysfunction, to ensure timely diagnosis and initiation of treatment. Clinicians should maintain a high index of suspicion for HLH and be aware that HLH may mimic the findings on liver biopsy seen in neonatal hemochromatosis.


Asunto(s)
Hemocromatosis/diagnóstico , Linfohistiocitosis Hemofagocítica/diagnóstico , Diagnóstico Diferencial , Humanos , Lactante , Masculino
6.
Mult Scler ; 25(1): 81-91, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29064315

RESUMEN

BACKGROUND: The hygiene hypothesis suggests that microbial replacement may be therapeutic in allergic and autoimmune diseases. Nevertheless, the results of helminth treatment, including in multiple sclerosis (MS), have been inconclusive. OBJECTIVE: To assess safety and brain magnetic resonance imaging (MRI) activity in subjects with relapsing-remitting multiple sclerosis (RRMS) during oral administration of ova from the porcine whipworm, Trichuris suis (TSO). METHODS: A total of 16 disease-modifying treatment (DMT) naive RRMS subjects were studied in a baseline versus treatment (BVT) controlled prospective study. MRI scans were performed during 5 months of screening-observation, 10 months of treatment, and 4 months of post-treatment surveillance. RESULTS: No serious symptoms or adverse events occurred during treatment. For the cohort, there was a trend consistent with a 35% diminution in active lesions when observation MRIs were compared to treatment MRIs ( p = 0.08), and at the level of individuals, 12 of 16 subjects improved during TSO treatment. T regulatory lymphocytes were increased during TSO treatment. CONCLUSION: TSO is safe in RRMS subjects. Potentially favorable MRI outcomes and immunoregulatory changes were observed during TSO treatment; however, the magnitude of these effects was modest, and there was considerable variation among the responses of individual subjects.


Asunto(s)
Helmintiasis , Inmunoterapia/métodos , Esclerosis Múltiple Recurrente-Remitente/terapia , Evaluación de Resultado en la Atención de Salud , Trichuris , Adulto , Animales , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/sangre , Esclerosis Múltiple Recurrente-Remitente/inmunología , Esclerosis Múltiple Recurrente-Remitente/patología , Óvulo , Estudios Prospectivos , Linfocitos T Reguladores , Adulto Joven
7.
Semin Diagn Pathol ; 34(2): 126-137, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28143798

RESUMEN

Hepatocellular carcinoma (HCC) is the most common primary hepatic malignant neoplasm in adults. Clinically, it tends to present late, and its prognosis historically has been poor, due to limited treatment options at the more advanced stage. A multidisciplinary approach for surveillance and early diagnosis of hepatocellular carcinoma in high-risk populations, combined with advances in surgical and other forms of ablative or chemotherapy, has greatly improved outcomes for patients with this tumor. Liver biopsies for HCC are becoming rare, being performed only for lesions that are atypical on imaging, to avoid the risk of bleeding or of inadvertently seeding the needle tract with HCC. HCC, a tumor of varied appearance, can be diagnostically challenging, particularly on a liver biopsy, due to sampling errors. Although HCC typically occurs on a background of cirrhosis, or advanced fibrosis, it may also arise in the noncirrhotic liver. Well-differentiated HCC may be hard to distinguish from benign lesions in the noncirrhotic liver and premalignant lesions in the cirrhotic liver, whereas a poorly-differentiated neoplasm may be difficult to tell apart from metastases or primary intrahepatic cholangiocarcinoma. Additionally, variant forms of HCC may mimic other neoplasms. This case-based review discusses typical HCC, the increasingly recognized steatohepatitic variant of HCC, the rare scirrhous variant of HCC and the extremely rare and clinically challenging cirrhotomimetic HCC.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patología , Anciano , Humanos , Masculino , Persona de Mediana Edad
8.
Ann Surg ; 265(6): 1183-1191, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27280500

RESUMEN

OBJECTIVE: To determine the therapeutic effects of dietary supplementation on Clostridium difficile infection (CDI). BACKGROUND: With limited treatment options, the rise of C. difficile-associated disease has spurred on the search for novel therapies. Recent data define a role for the aryl hydrocarbon receptor (AHR) and diet-derived AHR ligands in mucosal immunity. We investigated the efficacy of indole-3-carbinol (I3C), a dietary supplement, and AHR precursor ligand in a murine model of CDI. METHODS: C57BL/6 (B6), AHR, and AHR mice were placed on either grain-based or semipurified diets with or without I3C before and during CDI. Mice were followed clinically for a minimum of 6 days or euthanized between days 0 and 4 of inoculation for analysis of the inflammatory response and microbiota. RESULTS: B6 mice fed an AHR ligand-deficient, semipurified diet have significantly increased disease severity (P<0.001) and mortality (P < 0.001) compared with mice fed on diet containing I3C. The addition of I3C to the diet of AHR null mice had less of an impact than in AHR heterozygous littermates, although some protection was seen. Mice on semipurified I3C-diet had increased cecal Tregs, ILC3s, and γδ T cells and an increased neutrophilic response without increased inflammation or bacterial translocation compared with controls. CONCLUSIONS: I3C is a powerful treatment to reduce impact of CDI in mice. The findings indicate I3C may be acting through both AHR-dependent and -independent mechanisms in this model. Dietary supplementation with I3C is a potential new therapy for prevention and amelioration of C. difficile disease.


Asunto(s)
Clostridioides difficile , Infecciones por Clostridium/dietoterapia , Suplementos Dietéticos , Indoles/uso terapéutico , Animales , Antibacterianos/uso terapéutico , Traslocación Bacteriana , Infecciones por Clostridium/tratamiento farmacológico , Infecciones por Clostridium/inmunología , Modelos Animales de Enfermedad , Inmunidad Mucosa , Masculino , Ratones Endogámicos C57BL , Activación Neutrófila , Receptores de Hidrocarburo de Aril/inmunología , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
9.
ACG Case Rep J ; 4: e124, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29299484

RESUMEN

Microscopic colitis (MC) has rarely been described to be the cause of watery diarrhea in those with established inflammatory bowel disease (IBD), and instead has been presented as a herald syndrome to eventual IBD or incidentally found in asymptomatic IBD patients. We report a case series of 7 patients with IBD who presented with a watery diarrheal exacerbation due to new-onset MC. We propose that new-onset MC should be considered in the differential diagnosis of watery diarrhea occurring in patients with long-standing IBD and that evaluation should include colonoscopy with biopsies obtained throughout the colon.

10.
PLoS One ; 10(8): e0132727, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26252492

RESUMEN

Microsatellite instability (MSI) occurs in over 90% of Lynch syndrome cancers and is considered a hallmark of the disease. MSI is an early event in colon tumor development, but screening polyps for MSI remains controversial because of reduced sensitivity compared to more advanced neoplasms. To increase sensitivity, we investigated the use of a novel type of marker consisting of long mononucleotide repeat (LMR) tracts. Adenomas from 160 patients, ranging in age from 29-55 years old, were screened for MSI using the new markers and compared with current marker panels and immunohistochemistry standards. Overall, 15 tumors were scored as MSI-High using the LMRs compared to 9 for the NCI panel and 8 for the MSI Analysis System (Promega). This difference represents at least a 1.7-fold increase in detection of MSI-High lesions over currently available markers. Moreover, the number of MSI-positive markers per sample and the size of allelic changes were significantly greater with the LMRs (p = 0.001), which increased confidence in MSI classification. The overall sensitivity and specificity of the LMR panel for detection of mismatch repair deficient lesions were 100% and 96%, respectively. In comparison, the sensitivity and specificity of the MSI Analysis System were 67% and 100%; and for the NCI panel, 75% and 97%. The difference in sensitivity between the LMR panel and the other panels was statistically significant (p<0.001). The increased sensitivity for detection of MSI-High phenotype in early colorectal lesions with the new LMR markers indicates that MSI screening for the early detection of Lynch syndrome might be feasible.


Asunto(s)
Neoplasias Colorrectales/genética , Detección Precoz del Cáncer/métodos , Inestabilidad de Microsatélites , Adulto , Alelos , Biomarcadores de Tumor/genética , Reparación de la Incompatibilidad de ADN/genética , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Proteínas Proto-Oncogénicas B-raf/genética , Sensibilidad y Especificidad
11.
Hepatology ; 62(5): 1444-55, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26224591

RESUMEN

UNLABELLED: Emerging magnetic resonance imaging (MRI) biomarkers of hepatic steatosis have demonstrated tremendous promise for accurate quantification of hepatic triglyceride concentration. These methods quantify the proton density fat-fraction (PDFF), which reflects the concentration of triglycerides in tissue. Previous in vivo studies have compared MRI-PDFF with histologic steatosis grading for assessment of hepatic steatosis. However, the correlation of MRI-PDFF with the underlying hepatic triglyceride content remained unknown. The aim of this ex vivo study was to validate the accuracy of MRI-PDFF as an imaging biomarker of hepatic steatosis. Using ex vivo human livers, we compared MRI-PDFF with magnetic resonance spectroscopy-PDFF (MRS-PDFF), biochemical triglyceride extraction, and histology as three independent reference standards. A secondary aim was to compare the precision of MRI-PDFF relative to biopsy for the quantification of hepatic steatosis. MRI-PDFF was prospectively performed at 1.5 Tesla in 13 explanted human livers. We performed colocalized paired evaluation of liver fat content in all nine Couinaud segments using single-voxel MRS-PDFF (n=117) and tissue wedges for biochemical triglyceride extraction (n=117), and five core biopsies performed in each segment for histologic grading (n=585). Accuracy of MRI-PDFF was assessed through linear regression with MRS-PDFF, triglyceride extraction, and histology. Intraobserver agreement, interobserver agreement, and repeatability of MRI-PDFF and histologic grading were assessed through Bland-Altman analyses. MRI-PDFF showed an excellent correlation with MRS-PDFF (r=0.984, confidence interval 0.978-0.989) and strong correlation with histology (r=0.850, confidence interval 0.791-0.894) and triglyceride extraction (r=0.871, confidence interval 0.818-0.909). Intraobserver agreement, interobserver agreement, and repeatability showed a significantly smaller variance for MRI-PDFF than for histologic steatosis grading (all P<0.001). CONCLUSION: MRI-PDFF is an accurate, precise, and reader-independent noninvasive imaging biomarker of liver triglyceride content, capable of steatosis quantification over the entire liver.


Asunto(s)
Hígado/patología , Imagen por Resonancia Magnética/métodos , Enfermedad del Hígado Graso no Alcohólico/patología , Adulto , Anciano , Femenino , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Triglicéridos/análisis
12.
Liver Transpl ; 19(12): 1377-86, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24115392

RESUMEN

In patients who undergo liver transplantation for alcoholic liver disease (ALD), alcohol relapse is common. A return to abusive or excessive drinking likely decreases overall survival; however, the effects of alcohol use on allograft outcomes and histopathology are less well defined. We reviewed all cases of liver transplantation with ALD as an indication between January 1, 1995 and December 31, 2007. Allograft outcomes and histopathological results were compared for patients who relapsed into alcohol use and patients who maintained abstinence. Three hundred patients who underwent transplantation for ALD during this period survived at least 1 year, and 48 (16.0%) relapsed into alcohol use that came to clinical attention. The pattern of relapse was a single event for 10 patients (20.8%), intermittent relapses for 22 patients (45.8%), and continuous heavy drinking for 16 patients (33.3%). Continuous heavy drinking was associated with allograft loss in a univariate Cox proportional hazards analysis [hazard ratio (HR) = 2.43, 95% confidence interval (CI) = 1.26-4.68, P = 0.008] and in a multivariate Cox proportional hazards regression (HR = 2.57, 95% CI = 1.32-5.00, P = 0.006). A matched-pair analysis that controlled for the hepatitis C virus status and the time to biopsy compared the results of allograft histopathology for patients who relapsed into alcohol use and patients who maintained abstinence. Significant steatosis [odds ratio (OR) = 3.46, 95% CI = 1.29-9.31, P = 0.01], steatohepatitis (OR = 6.2, 95% CI = 1.70-22.71, P = 0.006), and advanced (stage 3 or higher) fibrosis (OR = 23.18, 95% CI = 3.01-177.30, P = 0.003) were associated with alcohol relapse. In conclusion, alcohol relapse after liver transplantation (particularly heavy drinking) is associated with decreased graft survival and advanced allograft fibrosis.


Asunto(s)
Alcoholismo/complicaciones , Supervivencia de Injerto , Cirrosis Hepática Alcohólica/cirugía , Trasplante de Hígado , Adulto , Anciano , Abstinencia de Alcohol , Alcoholismo/diagnóstico , Alcoholismo/prevención & control , Biopsia , Distribución de Chi-Cuadrado , Femenino , Humanos , Estimación de Kaplan-Meier , Cirrosis Hepática Alcohólica/diagnóstico , Cirrosis Hepática Alcohólica/etiología , Modelos Logísticos , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Modelos de Riesgos Proporcionales , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
13.
Liver Transpl ; 19(10): 1132-41, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23873778

RESUMEN

The significance of preexisting donor-specific HLA antibodies (HLA-DSAs) for liver allograft function is unclear. Our previous studies have shown that humoral alloreactivity frequently accompanies acute cellular rejection (ACR). In the present study, we set out to determine whether pretransplant HLA-DSAs correlate with clinically significant ACR in the first 90 days after transplantation and, if so, to determine their predictive values. Class I HLA-DSAs and class II HLA-DSAs were determined by single-antigen bead flow cytometry for 113 consecutive adult transplants. A statistical analysis was performed for data from 109 consecutive patients with graft survival greater than or equal to 90 days. All patients who developed biochemical graft dysfunction underwent liver biopsy for hematoxylin-eosin and complement component 4d staining. Cox proportional hazards models and associated hazard ratios revealed a significant association of pretransplant HLA-DSAs with clinically significant ACR: this association started with a mean fluorescence intensity (MFI) as low as 300 for both class I (hazard ratio = 2.7, P < 0.01) and class II (hazard ratio = 6.0, P < 0.01). Pretransplant HLA-DSAs were associated with an increased risk of ACR: P < 0.01 for class I (42% versus 18%), P < 0.001 for class II (37% versus 7%), and P < 0.001 for either class I or II (36% versus 3%). Class I or II HLA-DSAs with an MFI ≥ 1000 had the best positive predictive value for clinically significant ACR at 46%, whereas class I or II HLA-DSAs with an MFI ≥ 300 had the best negative predictive value at 97.1%. Although our study was based on consecutive patients, it was limited by the relatively low number of single-center subjects. In conclusion, the present study indicates that pretransplant HLA-DSAs, even at low levels of allosensitization, correlate with the risk of clinically significant ACR. Our findings suggest that anti-human leukocyte antigen antibodies could serve as donor-specific markers of immunoreactivity to the liver graft.


Asunto(s)
Anticuerpos/química , Antígenos HLA/química , Fallo Hepático/inmunología , Fallo Hepático/terapia , Trasplante de Hígado/métodos , Sistema del Grupo Sanguíneo ABO , Adulto , Anciano , Biopsia , Complemento C4b/química , Femenino , Citometría de Flujo , Rechazo de Injerto , Supervivencia de Injerto , Prueba de Histocompatibilidad , Humanos , Hígado/patología , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/química , Periodo Posoperatorio , Valor Predictivo de las Pruebas , Prevalencia , Estudios Prospectivos , Curva ROC , Riesgo , Factores de Tiempo , Donantes de Tejidos
14.
Diagn Ther Endosc ; 2012: 193570, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23243384

RESUMEN

Background. i-scan is a software-driven technology that allows modifications of sharpness, hue, and contrast to enhance mucosal imaging. It uses postimage acquisition software with real-time mapping technology embedded in the endoscopic processor. Aims. To review applications of i-scan technology in clinical endoscopic practice. Methods. This is a case series of 20 consecutive patients who underwent endoscopic procedures where i-scan image enhancement algorithms were applied. The main outcome measures were to compare mucosal lesions with high-definition white light endoscopy (HD-WLE) and i-scan image enhancement for the application of diagnostic sampling and therapy. Results. 13 cases involving the upper GI tract and 7 cases of the lower GI tract are included. For upper GI tract pathology i-scan assisted in diagnosis or therapy of Barrett's esophagus with dysplasia, esophageal adenocarcinoma, HSV esophagitis, gastric MALT lymphoma, gastric antral intestinal metaplasia with dysplasia, duodenal follicular lymphoma, and a flat duodenal adenoma. For lower GI tract pathology i-scan assisted in diagnosis or therapy of right-sided serrated adenomas, flat tubular adenoma, rectal adenocarcinoma, anal squamous cell cancer, solitary rectal ulcer, and radiation proctitis. Conclusions. i-scan imaging provides detailed topography of mucosal surfaces and delineates lesion edges, which can directly impact endoscopic management.

15.
Can J Gastroenterol ; 26(10): 691-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23061060

RESUMEN

BACKGROUND: Endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) is often used to assist in the evaluation of pancreatic lesions and may help to diagnose benign versus malignant neoplasms. However, there is a paucity of literature regarding comparative EUS characteristics of various malignant pancreatic neoplasms (primary and metastatic). OBJECTIVE: To compare and characterize primary pancreatic adenocarcinoma versus other malignant neoplasms, hereafter referred to as nonprimary pancreatic adenocarcinoma (NPPA), diagnosed by EUS-guided FNA. METHODS: The present study was a retrospective analysis of a prospectively maintained database. The setting was a tertiary care, academic medical centre. Patients referred for suspected pancreatic neoplasms were evaluated. Based on EUS-FNA characteristics, primary pancreatic adenocarcinoma was differentiated from other malignant neoplasms. The subset of other neoplasms was defined as malignant lesions that were 'NPPAs' (ie, predominantly solid or solid/cystic based on EUS appearance and primary malignant lesions or metastatic lesions to the pancreas). Pancreatic masses that were benign cystic lesions (pseudocyst, simple cyst, serous cystadenoma) and focal inflammatory lesions (acute, chronic and autoimmune pancreatitis) were excluded. RESULTS: A total of 230 patients were evaluated using EUS-FNA for suspected pancreatic mass lesions. Thirty-eight patients were excluded because they were diagnosed with inflammatory lesions or had purely benign cysts. One hundred ninety-two patients had confirmed malignant pancreatic neoplasms (ie, pancreatic adenocarcinoma [n=144], NPPA [n=48]). When comparing adenocarcinoma with NPPA lesions, there was no significant difference in mean age (P=0.0675), sex (P=0.3595) or average lesion size (P=0.3801). On average, four FNA passes were necessary to establish a cytological diagnosis in both lesion subtypes (P=0.396). Adenocarcinomas were more likely to be located in the pancreatic head (P=0.0198), whereas masses in the tail were more likely to be NPPAs (P=0.0006). Adenocarcinomas were also more likely to exhibit vascular invasion (OR 4.37; P=0.0011), malignant lymphadenopathy (P=0.0006), pancreatic duct dilation (OR 2.4; P=0.022) and common bile duct dilation (OR 2.87; P=0.039). CONCLUSIONS: Adenocarcinoma was more likely to be present in the head of the pancreas, have lymph node and vascular involvement, as well as evidence of pancreatic duct and common bile duct obstruction. Of all malignant pancreatic lesions analyzed by EUS-FNA, 25% were NPPA, suggesting that FNA is crucial in establishing a diagnosis and may be helpful in preoperative planning.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Anciano , Carcinoma Neuroendocrino/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Invest Radiol ; 47(10): 603-10, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22836309

RESUMEN

OBJECTIVE: The aim of this study was to compare dual-energy computed tomography (DECT) and magnetic resonance imaging (MRI) for fat quantification using tissue triglyceride concentration and histology as references in an animal model of hepatic steatosis. MATERIALS AND METHODS: This animal study was approved by our institution's Research Animal Resource Center. After validation of DECT and MRI using a phantom consisting of different triglyceride concentrations, a leptin-deficient obese mouse model (ob/ob) was used for this study. Twenty mice were divided into 3 groups based on expected levels of hepatic steatosis: low (n = 6), medium (n = 7), and high (n = 7) fat. After MRI at 3 T, a DECT scan was immediately performed. The caudate lobe of the liver was harvested and analyzed for triglyceride concentration using a colorimetric assay. The left lateral lobe was also extracted for histology. Magnetic resonance imaging fat-fraction (FF) and DECT measurements (attenuation, fat density, and effective atomic number) were compared with triglycerides and histology. RESULTS: Phantom results demonstrated excellent correlation between triglyceride content and each of the MRI and DECT measurements (r(2) ≥ 0.96, P ≤ 0.003). In vivo, however, excellent triglyceride correlation was observed only with attenuation (r(2) = 0.89, P < 0.001) and MRI-FF (r(2) = 0.92, P < 0.001). Strong correlation existed between attenuation and MRI-FF (r(2) = 0.86, P < 0.001). Nonlinear correlation with histology was also excellent for attenuation and MRI-FF. CONCLUSIONS: Dual-energy computed tomography (CT) data generated by the current Gemstone Spectral Imaging analysis tool do not improve the accuracy of fat quantification in the liver beyond what CT attenuation can already provide. Furthermore, MRI may provide an excellent reference standard for liver fat quantification when validating new CT or DECT methods in human subjects.


Asunto(s)
Hígado Graso/patología , Hígado/patología , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Animales , Modelos Animales de Enfermedad , Hígado Graso/metabolismo , Hígado/metabolismo , Ratones , Fantasmas de Imagen , Valores de Referencia , Reproducibilidad de los Resultados , Triglicéridos/metabolismo
17.
Case Rep Gastroenterol ; 6(2): 285-92, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22754488

RESUMEN

Probe-based confocal laser endomicroscopy (pCLE) is a novel imaging technique which utilizes a low-power laser light passed through a fiber-optic bundle, within a miniprobe that is advanced into the working channel, to obtain microscopic images of the mucosa. This allows the endoscopist to evaluate the microarchitecture of the gastrointestinal epithelium in real time. At this time pCLE cannot replace histopathology, but it can provide diagnostic information as well as guide therapeutic management in patients with Barrett's esophagus (BE) with high-grade dysplasia (HGD). We describe a retrospective case series in which four patients with BE and biopsy-proven HGD underwent endoscopy with pCLE to direct real-time endoscopic ablation therapy and/or endoscopic mucosal resection (EMR), which was performed in conjunction with pCLE. All four patients had pCLE showing features of HGD. After either EMR or radiofrequency ablation (RFA), pCLE was again used to evaluate the margins after therapy to assure accuracy. In one case, pCLE had features of dysplasia at the margin and further repeat EMR was immediately performed. Another case had a normal-appearing esophagus, but pCLE found features of BE in discrete areas and targeted biopsies were performed, which confirmed BE. This patient subsequently underwent RFA therapy of the residual areas of BE. In conclusion, in patients with BE and dysplasia, pCLE is an effective tool used to target biopsies, guide endoscopic therapy and assess the accuracy of EMR or RFA.

18.
Phys Med Biol ; 57(8): 2273-86, 2012 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-22459948

RESUMEN

Recent advances in elastography have provided several imaging modalities capable of quantifying the elasticity of tissue, an intrinsic tissue property. This information is useful for determining tumour margins and may also be useful for diagnosing specific tumour types. In this study, we used dynamic compression testing to quantify the viscoelastic properties of 16 human hepatic primary and secondary malignancies and their corresponding background tissue obtained following surgical resection. Two additional backgrounds were also tested. An analysis of the background tissue showed that F4-graded fibrotic liver tissue was significantly stiffer than F0-graded tissue, with a modulus contrast of 4:1. Steatotic liver tissue was slightly stiffer than normal liver tissue, but not significantly so. The tumour-to-background storage modulus contrast of hepatocellular carcinomas, a primary tumour, was approximately 1:1, and the contrast decreased with increasing fibrosis grade of the background tissue. Ramp testing showed that the background stiffness increased faster than the malignant tissue. Conversely, secondary tumours were typically much stiffer than the surrounding background, with a tumour-to-background contrast of 10:1 for colon metastases and 10:1 for cholangiocarcinomas. Ramp testing showed that colon metastases stiffened faster than their corresponding backgrounds. These data have provided insights into the mechanical properties of specific tumour types, which may prove beneficial as the use of quantitative stiffness imaging increases.


Asunto(s)
Fuerza Compresiva , Elasticidad , Neoplasias Hepáticas/patología , Fenómenos Biomecánicos , Hígado Graso/complicaciones , Humanos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Estrés Mecánico , Viscosidad
19.
Case Rep Gastrointest Med ; 2012: 826246, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23304576

RESUMEN

Adenocarcinoma of the cervical esophagus is a rare tumor, in comparison to adenocarcinoma of the distal esophagus which is on the rise and is often associated with Barrett's esophagus. We present a case of aggressive cervical esophageal adenocarcinoma in a 46-year-old female with no endoscopic or histopathologic evidence of Barrett's esophagus. We discuss the possible etiology of this tumor and review the treatment options, highlighting the importance of a multidisciplinary approach to the management of this rare disease.

20.
J Magn Reson Imaging ; 35(4): 844-51, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22127834

RESUMEN

PURPOSE: To validate the utility and performance of a T 2 correction method for hepatic fat quantification in an animal model of both steatosis and iron overload. MATERIALS AND METHODS: Mice with low (n = 6), medium (n = 6), and high (n = 8) levels of steatosis were sedated and imaged using a chemical shift-based fat-water separation method to obtain magnetic resonance imaging (MRI) fat-fraction measurements. Imaging was performed before and after each of two superparamagnetic iron oxide (SPIO) injections to create hepatic iron overload. Fat-fraction maps were reconstructed with and without T 2 correction. Fat-fraction with and without T 2 correction and T 2 measurements were compared after each injection. Liver tissue was harvested and imaging results were compared to triglyceride extraction and histology grading. RESULTS: Excellent correlation was seen between MRI fat-fraction and tissue-based fat quantification. Injections of SPIOs led to increases in R 2 (=1/T 2). Measured fat-fraction was unaffected by the presence of iron when T 2 correction was used, whereas measured fat-fraction dramatically increased without T 2 correction. CONCLUSION: Hepatic fat-fraction measured using a T 2-corrected chemical shift-based fat-water separation method was validated in an animal model of steatosis and iron overload. T 2 correction enables robust fat-fraction estimation in both the presence and absence of iron, and is necessary for accurate hepatic fat quantification.


Asunto(s)
Adiposidad , Artefactos , Modelos Animales de Enfermedad , Hígado Graso/patología , Sobrecarga de Hierro/patología , Imagen por Resonancia Magnética/métodos , Animales , Biomarcadores , Hígado Graso/complicaciones , Hígado Graso/metabolismo , Humanos , Sobrecarga de Hierro/complicaciones , Sobrecarga de Hierro/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Tamaño de los Órganos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Triglicéridos/análisis
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