10 results on '"Cunha, Guilherme M."'
Search Results
2. Dynamic contrast-enhanced MRI perfusion quantification in hepatocellular carcinoma: comparison of gadoxetate disodium and gadobenate dimeglumine
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Stocker, Daniel, Hectors, Stefanie, Bane, Octavia, Vietti-Violi, Naik, Said, Daniela, Kennedy, Paul, Cuevas, Jordan, Cunha, Guilherme M., Sirlin, Claude B., Fowler, Kathryn J., Lewis, Sara, and Taouli, Bachir
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- 2021
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3. Examining LI-RADS recommendations: should observation size only be measured on non-arterial phases?
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Cunha, Guilherme M., Kwon, Heejin, Wolfson, Tanya, Gamst, Anthony C., Chung, Yong Eun, Kim, Min-Jeong, Kim, Sang Won, Sirlin, Claude B., and Fowler, Kathryn J.
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- 2020
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4. Adaptive local window for level set segmentation of CT and MRI liver lesions
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Hoogi, Assaf, Beaulieu, Christopher F., Cunha, Guilherme M., Heba, Elhamy, Sirlin, Claude B., Napel, Sandy, and Rubin, Daniel L.
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- 2017
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5. Comparative efficacy of an optimal exam between ultrasound versus abbreviated MRI for HCC screening in NAFLD cirrhosis: A prospective study.
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Huang, Daniel Q., Fowler, Kathryn J., Liau, Joy, Cunha, Guilherme M., Louie, Ashley L., An, Julie Y., Bettencourt, Ricki, Jung, Jinho, Gitto, Zachary, Hernandez, Christie, Lopez, Scarlett J., Gupta, Hersh, Sirlin, Claude B., Marks, Robert M., and Loomba, Rohit
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MEDICAL screening ,NON-alcoholic fatty liver disease ,CIRRHOSIS of the liver ,MAGNETIC resonance imaging ,MAGNETIC resonance mammography ,LONGITUDINAL method ,SURVEILLANCE detection - Abstract
Summary: Background: Retrospective studies report that visualisation of the liver may be severely limited using ultrasound (US), potentially contributing to diminished sensitivity for detection of hepatocellular carcinoma (HCC) among patients with nonalcoholic fatty liver disease (NAFLD) and cirrhosis, but there are limited prospective data. Aims: To compare liver visualisation scores prospectively for US and abbreviated hepatobiliary phase (HBP) magnetic resonance imaging (AMRI) in a cohort of participants with NAFLD cirrhosis and a clinical indication for HCC surveillance. Methods: This prospective multicenter study included 54 consecutive participants (67% women) with NAFLD cirrhosis who underwent contemporaneous US as well as HBP‐AMRI with gadoxetic acid. Primary outcome was the proportion of imaging examinations with severe limitations in liver visualisation (visualisation score C) compared head‐to‐head between US and AMRI. Results: The mean (± standard deviation) age was 63.3 years (±8.4) and body mass index was 32.0 kg/m2 (±6.0). Nineteen participants (35%) had severe visualisation limitations on US, compared with 10 (19%) with AMRI, p < 0.0001. Nine (17%) participants had <90% of the liver visualised on US, compared with only 1 (2%) participant with AMRI, p < 0.0001. Obesity was a strong and independent predictor for severe visualisation limitation on US (OR 5.1, CI 1.1–23.1, p = 0.03), after adjustment for age, sex and ethnicity. Conclusion: More than one‐third of participants with NAFLD cirrhosis had severe visualisation limitations on US for HCC screening, compared with one‐sixth on AMRI. US adequacy should be reported in all clinical studies and when suboptimal then AMRI may be considered for HCC screening. [ABSTRACT FROM AUTHOR]
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- 2022
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6. LI-RADS and transplantation: challenges and controversies.
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Cunha, Guilherme M., Tamayo-Murillo, Dorathy E., and Fowler, Kathryn J.
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LIVER transplantation , *DIAGNOSIS , *HEPATOCELLULAR carcinoma , *TRANSPLANTATION of organs, tissues, etc. - Abstract
Patients with early stage hepatocellular carcinoma (HCC) can be cured by liver transplantation. HCC imaging features on CT or MRI are specific enough to allow for definitive diagnosis and treatment without the need of confirmatory biopsy. When applied to the appropriate at-risk population the Liver Imaging Reporting and Data System (LI-RADS) imaging criteria achieve high specificity and positive predictive value for the diagnosis of HCC. The Organ Procurement and Transplantation Network (OPTN) is the United States organization that aims to assure the adequate and fair distribution of livers across candidates. Given the importance of fair organ allocation, OPTN also provides stringent imaging criteria for the diagnosis of HCC aiming to avoid false positive diagnosis. Although most imaging criteria are identical for both systems, discrepancies between LI-RADS and the current OPTN classification system for HCC diagnosis exists. Main differences include, but are not limited to, the binary approach of OPTN to classify lesions as HCC or not, versus the probabilistic algorithmic approach of LI-RADS, technical and interpretation considerations, and the approach towards treated lesions. The purpose of this article is to highlight the similarities and discrepancies between LI-RADS and the current OPTN criteria for HCC diagnosis and the implications that these differences may have on the management of patients who are transplant candidates. [ABSTRACT FROM AUTHOR]
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- 2021
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7. The relationship between liver triglyceride composition and proton density fat fraction as assessed by 1H MRS.
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Hamilton, Gavin, Schlein, Alex N., Wolfson, Tanya, Cunha, Guilherme M., Fowler, Kathryn J., Middleton, Michael S., Loomba, Rohit, and Sirlin, Claude B.
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FATTY liver ,LIVER ,TRIGLYCERIDES ,PROTONS ,DOUBLE bonds - Abstract
The aim of this study was to estimate parameters determining liver triglyceride composition (TC) using 1H MRS and to assess how TC estimability is affected by proton density fat fraction (PDFF) in adults with nonalcoholic fatty liver disease (NAFLD). In this prospective single‐site study, 199 adults with known or suspected NAFLD in whom other causes of liver disease were excluded underwent two 1H MRS STimulated Echo Acquisition Method (STEAM) sequences at 3 T. A respiratory‐gated water‐suppressed free breathing sequence (TE 10 ms, 16 signal averages) was used to assess TC in terms of the number of double bonds (ndb) and methylene‐interrupted double bonds (nmidb), and a single breath‐hold‐long TR, multi‐TE sequence (TR 3500 ms), which acquired five single average spectra over TE 10‐30 ms, was used to estimate liver PDFF. Ndb and nmidb estimability was qualitatively assessed for each case and summarized descriptively. The consistency of ndb and nmidb estimation was examined using ROC analysis. The relationship between ndb and nmidb values and PDFF was presented graphically. Quality‐of‐fit of ndb and nmidb versus PDFF was evaluated by Pearson‐r correlation. A significance level of 0.05 was used. In 263 1H MRS examinations performed on 199 adult participants, ndb and nmidb were successfully estimated in 7/53 (13.2%) examinations with PDFF < 4%, 13/30 (43.3%) examinations with PDFF between 4% and 7%, 33/41 (80.5%) examinations with PDFF between 7% and 10%, and 124/139 (89.2%) examinations with PDFF > 10% (maximum PDFF 38.1%). Liver TC could be estimated consistently for PDFF > 6.7%. Both ndb and nmidb decreased with increasing PDFF (ndb = 2.83‐0.0160·PDFF, r = ‐0.449, P < 0.0001); nmidb = 0.75‐0.0088·PDFF, r = ‐0.350, P < 0.0001). In a cohort of adults with known or suspected NAFLD, liver TC becomes more saturated as PDFF increases. [ABSTRACT FROM AUTHOR]
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- 2020
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8. Changes in the Management of Patients with Crohn's Disease Based on Magnetic Resonance Enterography Patterns.
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Chinem, Evelyn Sayuri S., Esberard, Barbara C., Moreira, Andre da L., Barbassa, Tatiana G., da Cunha, Guilherme M., Carneiro, Antonio Jose de V., de Souza, Heitor S., and Carvalho, Ana Teresa P.
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CROHN'S disease ,MAGNETIC resonance ,PATIENT decision making ,DISEASE duration ,ABDOMINAL diseases - Abstract
Background and Aims. Magnetic resonance enterography (MRE) has become an important modality of radiological imaging in the evaluation of Crohn's disease (CD). The aim of this study was to investigate the impact of MRE in the assessment of disease activity and abdominal complications and in the making of therapeutic decisions for patients with CD. Methods. In a cross-sectional retrospective study, we selected 74 patients with CD who underwent MRE and ileocolonoscopy with an interval between the two exams of up to 30 days between January 2011 and December 2017. We assessed the parameters of the images obtained by MRE and investigated the agreement with the level of disease activity and complications determined by a clinical evaluation, inflammatory biomarkers, and endoscopy, as well as the resulting changes in medical and surgical management. Results. Changes in medical management were detected in 41.9% of patients. Significant changes in medical decisions were observed in individuals with a purely penetrating (P =.012) or a mixed (P =.024) MRE pattern. Patients with normal MRE patterns had a correlation with unchanged medical decisions (P =.001). There were statistically significant agreements between the absence of inflammatory criteria on MRE and remission according to the Harvey and Bradshaw index (HBI) (P =.037), the presence of inflammatory criteria on MRE and positive results for calprotectin (P =.005), and penetrating criteria on MRE and the scoring endoscopic system for Crohn's disease (SES-CD), indicating active disease (P =.048). Finally, there was significant agreement between the presence of fibrostenotic criteria and a long disease duration (P =.027). Conclusion. MRE discloses disease activity and complications not apparent with other modalities and results in changes in therapeutic decisions. In addition to being used for diagnosis, MRE should be routinely used in the follow-up of CD patients. [ABSTRACT FROM AUTHOR]
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- 2019
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9. Right and left ventricular function and myocardial scarring in adult patients with sickle cell disease: a comprehensive magnetic resonance assessment of hepatic and myocardial iron overload.
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Junqueira, Flávia P., Fernandes, Juliano L., Cunha, Guilherme M., Kubo, Tadeu T. A., Lima, Claudio M. A. O., Lima, Daniel B. P., Uellendhal, Marly, Sales, Sidney R., Cunha, Carolina A. S., de Pessoa, Viviani L. R., Lobo, Clarisse L. C., and Marchiori, Edson
- Abstract
Background: Patients with Sickle cell disease (SCD) who receive regular transfusions are at risk for developing cardiac toxicity from iron overload. The aim of this study was to assess right and left cardiac volumes and function, late gadolinium enhancement (LGE) and iron deposits in patients with SCD using CMR, correlating these values with transfusion burden, ferritin and hemoglobin levels. Methods: Thirty patients with SCD older than 20 years of age were studied in a 1.5 T scanner and compared to age- and sex-matched normal controls. Patients underwent analysis of biventricular volumes and function, LGE and T2* assessment of the liver and heart. Results: When compared to controls, patients with SCD presented higher left ventricular (LV) volumes with decreased ejection fraction (EF) with an increase in stroke volume (SV) and LV hypertrophy. The right ventricle (RV) also presented with a decreased EF and hypertrophy, with an increased end-systolic volume. Although twenty-six patients had increased liver iron concentrations (median liver iron concentration value was 11.83 ± 9.66 mg/g), only one patient demonstrated an abnormal heart T2* < 20 msec. Only four patients (13%) LGE, with only one patient with an ischemic pattern. Conclusions: Abnormal heart iron levels and myocardial scars are not a common finding in SCD despite increased liver iron overload. The significantly different ventricular function seen in SCD compared to normal suggests the changes in RV and LV function may not be due to the anemia alone. Future studies are necessary to confirm this association. [ABSTRACT FROM AUTHOR]
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- 2013
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10. Changes in abdominal adipose tissue depots assessed by MRI correlate with hepatic histologic improvement in non-alcoholic steatohepatitis.
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Shen, Wei, Middleton, Michael S., Cunha, Guilherme M., Delgado, Timoteo I., Wolfson, Tanya, Gamst, Anthony, Fowler, Kathryn J., Alazraki, Adina, Trout, Andrew T., Ohliger, Michael A., Shah, Shetal N., Bashir, Mustafa R., Kleiner, David E., Loomba, Rohit, Neuschwander-Tetri, Brent A., Sanyal, Arun J., Zhou, Jane, Sirlin, Claude B., and Lavine, Joel E.
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ABDOMINAL adipose tissue , *LIVER histology , *NON-alcoholic fatty liver disease , *FATTY liver , *ADIPOSE tissues , *ADIPOSE tissue diseases , *MAGNETIC resonance imaging - Abstract
Non-alcoholic steatohepatitis (NASH) is prevalent in adults with obesity and can progress to cirrhosis. In a secondary analysis of prospectively acquired data from the multicenter, randomized, placebo-controlled FLINT trial, we investigated the relationship between reduction in adipose tissue compartment volumes and hepatic histologic improvement. Adult participants in the FLINT trial with paired liver biopsies and abdominal MRI exams at baseline and end-of-treatment (72 weeks) were included (n = 76). Adipose tissue compartment volumes were obtained using MRI. Treatment and placebo groups did not differ in baseline adipose tissue volumes, or in change in adipose tissue volumes longitudinally (p = 0.107 to 0.745). Deep subcutaneous adipose tissue (dSAT) and visceral adipose tissue volume reductions were associated with histologic improvement in NASH (i.e., NAS [non-alcoholic fatty liver disease activity score] reductions of ≥2 points, at least 1 point from lobular inflammation and hepatocellular ballooning, and no worsening of fibrosis) (p = 0.031, and 0.030, respectively). In a stepwise logistic regression procedure, which included demographics, treatment group, baseline histology, baseline and changes in adipose tissue volumes, MRI hepatic proton density fat fraction (PDFF), and serum aminotransferases as potential predictors, reductions in dSAT and PDFF were associated with histologic improvement in NASH (regression coefficient = -2.001 and -0.083, p = 0.044 and 0.033, respectively). In adults with NASH in the FLINT trial, those with greater longitudinal reductions in dSAT and potentially visceral adipose tissue volumes showed greater hepatic histologic improvements, independent of reductions in hepatic PDFF. NCT01265498. Although central obesity has been identified as a risk factor for obesity-related disorders including insulin resistance and cardiovascular disease, the role of central obesity in non-alcoholic steatohepatitis (NASH) warrants further clarification. Our results highlight that a reduction in central obesity, specifically deep subcutaneous adipose tissue and visceral adipose tissue, may be related to histologic improvement in NASH. The findings from this analysis should increase awareness of the importance of lifestyle intervention in NASH for clinical researchers and clinicians. Future studies and clinical practice may design interventions that assess the reduction of deep subcutaneous adipose tissue and visceral adipose tissue as outcome measures, rather than simply weight reduction. [Display omitted] • This is a secondary analysis of a subgroup of patients who had MRI exams in the FLINT trial. • Those with NASH who experienced a greater loss of deep subcutaneous adipose tissue showed greater histologic improvement. • Patients with greater loss of visceral adipose tissue probably also had greater levels of histologic improvement. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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