About

Michael Thomas Corwin, M.D., is a professor and the Director of Abdominal MRI at UC Davis Health, with a focus on abdominal radiology. His clinical expertise includes MRI, CT, ultrasound, and fluoroscopy, with a primary emphasis on abdominal MRI. His clinical interests encompass adrenal imaging, hepatobiliary imaging, and the management of incidental findings at abdominal CT. Dr. Corwin's research interests include adrenal and renal imaging, hepatobiliary imaging, and the management of incidental findings at abdominal CT. He completed his undergraduate education with a B.A. from the University of Rochester in 2000 and earned his M.D. from Duke University in 2004. His postgraduate training includes an internship at Virginia Mason Medical Center, a residency in Radiology and Abdominal Imaging at Brown University/Rhode Island Hospital, and a fellowship in Abdominal Imaging at Beth Israel Deaconess Medical Center. Dr. Corwin has received awards such as the Roscoe E. Miller Best GI Paper Presentation Award and the Rush Rees Academic Scholarship. His scholarly work includes numerous publications in the field of radiology, emphasizing adrenal and liver imaging, incidental findings, and imaging techniques.

Research topics

• Medicine
• Radiology
• Internal medicine
• Pathology
• Political Science
• Medical physics
• General surgery
• Obstetrics
• Nuclear medicine
• Gynecology

Selected publications

• Update on Management of Incidental Findings Seen on Imaging Studies of the Abdomen and Pelvis

  Radiographics · 2026-03-05

  articleSenior author

  Since the publication of the American College of Radiology white papers on incidental findings in the abdomen and pelvis, numerous studies have been published that either support or contradict existing guidelines or address common incidental findings for which no white paper exists.

  PublisherDOI

• Quantification of Imaging Suite–Level Energy Patterns in MRI, CT, and PET/CT to Guide Energy Efficiency

  Radiology · 2026-04-01

  article

  Background The urgency for systemic change in how care, particularly energy-intensive advanced imaging services, is delivered and managed is evident, as the emissions associated with these services are adversely affecting human health. Although the energy demand from the main power supply (ie, electricity directly powering the imaging hardware) has been well characterized, imaging suite-level quantification that includes the heating, ventilation, and air conditioning (HVAC) and chilled water subsystems is not yet understood. Purpose To comprehensively assess imaging suite-level energy by quantifying energy demands from main power, HVAC, and chilled water subsystems. Materials and Methods Power, temperature, and flow meters were permanently installed in four imaging suites (3-T MRI, 1.5-T MRI, CT, and PET/CT) to measure energy patterns for the main power, HVAC, and MRI chilled water subsystems in an outpatient facility. Software was developed to calculate suite-level energy consumption over a 30-day period. Descriptive statistics were used to summarize power and energy consumption values across all subsystems (main power, HVAC, and chilled water) and imaging suites. Results Projected suite-level total annual energy consumption was 277.9, 211.5, 54.8, and 117.2 MWh for the 3-T MRI, 1.5-T MRI, CT, and PET/CT suites, respectively, equivalent to the annual electricity use of 25.8, 19.6, 5.1, and 10.9 average U.S. homes. Main power dominated MRI suite energy demand, accounting for 64.63% (179.6 of 277.9 MWh per year) and 72.72% (153.8 of 211.5 MWh per year) of the total for 3-T and 1.5-T MRI, respectively. The HVAC (9.97% [27.7 of 277.9]; 17.45% [36.9 of 211.5], respectively) and chilled water (25.40% [70.6 of 277.9]; 9.83% [20.8 of 211.5], respectively) subsystems also contributed. In CT and PET/CT suites, HVAC was the primary driver of demand (68.8% [37.7 of 54.8 MWh per year]; 64.76% [75.9 of 117.2 MWh per year], respectively), with the remaining attributed to main power. Conclusion Suite-level quantification revealed modality- and subsystem-specific energy patterns, where main power dominated MRI suite energy, and HVAC dominated CT and PET/CT suite energy. © RSNA, 2026

  PublisherDOI

• Reply to “Follow-Up Requirements for 1- to 4-cm Indeterminate Adrenal Nodules: Aligning Data and Recommendations”

  American Journal of Roentgenology · 2026-02-11

  article1st authorCorresponding
  PublisherDOI

• Prevalence of Malignancy Among Incidental Indeterminate Adrenal Nodules on Contrast-Enhanced CT in Patients Without Known Cancer: A Multiinstitutional Study

  American Journal of Roentgenology · 2025-11-19 · 2 citations

  article1st authorCorresponding

  Follow-up imaging is not warranted for small (1-2 cm) incidental indeterminate adrenal nodules detected on contrast-enhanced CT in patients without known cancer.

  PublisherDOI

• Detection of microscopic fat in adrenal adenomas: comparison of 2D dual gradient-echo MRI and 3D two-point Dixon techniques

  Acta Radiologica · 2025-11-01

  articleSenior author

  Background Limited data exist comparing the detection of microscopic fat in adrenal adenomas on two-dimensional chemical shift dual-echo (2D CSI) magnetic resonance imaging (MRI) and three-dimensional two-point Dixon techniques (3D Dixon). Purpose To compare the sensitivity of 2D CSI versus 3D Dixon techniques for the diagnosis of adrenal adenomas. Material and Methods A retrospective analysis was conducted of 33 patients with adrenal masses who underwent both 2D CSI and 3D Dixon sequences on a 1.5-T scanner. Two blinded radiologists measured and calculated signal intensity (SI) index (SII) (100×(SI in phase – SI out of phase)/SI in phase) of nodules on each technique. Reference standard diagnosis of 30 adrenal adenomas was established. Sensitivity for adrenal adenoma diagnosis was determined using a SII >16.5%. Results In total, 33 nodules were investigated (mean size=22 mm, range=11–55 mm). Of the 30 adenomas, the mean SII on 2D CSI was 48% for reader 1 and 44% for reader 2, compared to 34% on 3D Dixon for both readers ( P < 0.001). Sensitivity for the diagnosis of adenoma with 2D CSI was 90% (95% confidence interval [CI]=82–98) for both readers, while 3D Dixon demonstrated a sensitivity of 73% (95% CI=65–82) for reader 1 and 63% (95% CI=55–72) for reader 2. Conclusion 2D dual gradient-echo CSI demonstrated a higher sensitivity for the diagnosis of adrenal adenoma than the 3D Dixon technique. Adrenal MRI evaluation of the adrenal glands at 1.5 T should include 2D dual gradient-echo CSI and not rely solely on 3D two-point Dixon techniques for the diagnosis of adrenal adenomas.

  PublisherDOI

• Quantification of ¹⁸ F-FDG Delivery Rate for Liver Inflammation Using Shortened Dynamic PET Imaging Protocols

  Journal of Nuclear Medicine · 2025-09-18

  article

  F-FDG [Formula: see text].

  PublisherDOI

• Spatial heterogeneity in liver stiffness does not predict clinical outcomes in patients with primary sclerosing cholangitis

  Hepatology Communications · 2025-10-07 · 1 citations

  articleOpen access

  BACKGROUND: Primary sclerosing cholangitis (PSC) is a cholestatic liver disease that can cause uneven fibrosis throughout the liver. Spatial heterogeneity in liver stiffness (LS) by magnetic resonance elastography (MRE) was compared in patients with PSC and metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: Variability of LS was defined as the difference between the maximum and minimum LS divided by the maximum LS. The coefficient of variation (CoV) was calculated as the SD of LS divided by the mean of LS. MREs were classified as homogenous or heterogenous if the variability of LS was less than or greater than the mean variability, respectively. RESULTS: A total of 105 patients (PSC: n=66, MASLD: n=39) were included. In both PSC and MASLD, the variability of LS increased with increasing mean LS (r=0.31, p=0.01 and r=0.57, p=0.0002, respectively). CoV correlated with mean LS in patients with MASLD (r=0.34, p=0.03), but not PSC (r=0.19, p=0.12). Among patients with PSC, neither variability nor CoV of LS were predictors of transplant-free survival (TFS) or hepatic decompensation (HD). Mean LS was a significant predictor of TFS (HR 1.52, p=0.004) and HD (HR 1.94, p<0.0001), independent of LS variability or CoV. CONCLUSIONS: Spatial heterogeneity of LS increases with progressive disease but is not associated with clinical outcomes in PSC. Mean LS predicts clinical outcomes in patients with PSC independent of LS spatial heterogeneity.

  PublisherDOI

• Imaging of Adrenal Tumors

  Magnetic Resonance Imaging Clinics of North America · 2025-08-13

  article
  PublisherDOI

• Quantifying the Radiotracer Delivery Rate in Immune Organs to Assess Liver Inflammation Using Total-Body PET

  2025-11-01

  article

  Metabolic dysfunction-associated steatotic liver disease (MASLD) is a multisystem disease and may be regulated by multiple extrahepatic factors. The immune system is increasingly recognized to affect MASLD pathophysiology. Previous studies have shown the promise of a parametric PET approach to assess liver inflammation in MASLD using the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">${ }^{18} \text{F-FDG}$</tex> delivery rate <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{K}_{1}$</tex>. As an inflammatory disease, there is potential for crosstalk between the liver and the immune organs. However, no studies have explored the relationship between liver inflammation and multiple immune organs simultaneously. In this work, we investigate the kinetic changes of bone marrow (BM) and spleen (two important immune organs) in the context of liver inflammation using total-body dynamic PET kinetic modeling. The evaluation included 26 MASLD patients and 14 healthy subjects who underwent a full <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$1-\mathrm{h}$</tex> dynamic <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">${ }^{18}\text{F-FDG}$</tex> PET scan using the uEXPLORER total-body PET scanner. Results show that a two-tissue irreversible model with time delay correction is necessary to model both BM and spleen dynamic data. The <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{K}_{1}$</tex> in these two organs was decreased in the high liver inflammation group, while this change was not observed for other parameters, including SUV and FDG influx rate <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{K}_{\mathrm{i}}$</tex>. When combining with liver <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{K}_{1}$</tex>, BM and spleen <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{K}_{1}$</tex> can further increase the performance of differentiating grades of liver inflammation.

  PublisherDOI

• 6637 A Rare Case of a Possible Non-functional (Clinically Silent Biochemically Negative) Adrenal Pheochromocytoma

  Journal of the Endocrine Society · 2024-10-01

  articleOpen access

  Abstract Disclosure: V.K. Babu: None. M.T. Corwin: None. S.T. Olatunbosun: None. Introduction: Adrenal pheochromocytomas (pheo) are rare neuroendocrine tumors arising from the chromaffin cells of the adrenal medulla. Their incidence is around 0.8 per 100,000 patient years. They are usually sporadic, with about 40% having a pre-existing familial genetic disease. About 3% of adrenal incidentalomas prove to be pheo. They have a heterogenous presentation and are diagnosed by measuring urinary and plasma fractionated metanephrines (met) and catecholamines (catecho). The diagnosis becomes challenging in patients presenting with small tumors and normal levels of biochemical metabolites, as in our patient. Clinical Case: A 32-year-old male with no significant past medical history was referred to us with a left adrenal incidentaloma of 1.2 cm x 1 cm with 23 Hounsfield units during a non-contrast CT scan performed for abdominal pain. He denied spells of headaches, excessive perspiration, palpitations, history of hypertension, hypokalemia, history of kidney stones, fractures, muscle weakness, easy bruisability, new abdominal striae, change in weight, steroid use, or family history of endocrine tumors. MRI with adrenal protocol 3 months later showed a 1.2 cm x 1.4 cm left adrenal nodule that was markedly hyperintense on T2-weighted and hypointense on T1-weighted images without microscopic fat, suspicious for a pheo. It also demonstrated peripheral enhancement with progressive central filling on the delayed images without washout. Plasma met and catecho were normal: normetanephrines (normet) (45.2 pg/mL), met (36.4 pg/mL), epinephrine (epi) (34 pg/mL), norepinephrine (norepi) (295 pg/mL) and dopamine (&amp;lt;30 pg/mL). Subsequent 24-hour urine testing revealed normal met (155 mcg/day, 154 mcg/day), and normal normet (248 mcg/day, 236 mcg/day) on two separate occasions, and normal epi (9 mcg/L), norepi (36 mcg/day), and dopamine (228 mcg/day). The patient was subsequently referred to Endocrine Surgery for evaluation. Conclusion: Our patient likely has a non-functional pheo. Another possibility is an adrenal hemangioma, which would show discontinuous peripheral nodular enhancement in addition to progressive central filling. Patients with pheo less than 2 cm may present with normal biochemical testing. The size of a pheo is usually proportional to the levels of its biochemical metabolites. This case is unique because patients with a similar sized pheo are expected to have 3 times higher levels of plasma met and catecho, even if still within normal limits. It is important to take tumor size into consideration when interpreting labs to determine its functional status. This may help in determining the need for a pre-operative alpha blockade prior to adrenal surgery. A definitive diagnosis of a pheo’s non-functional status can only be confirmed after histopathological examination of the tumor tissue. Presentation: 6/3/2024

  PublisherOA PDFDOI

Frequent coauthors

• Ghaneh Fananapazir

  University of California, Davis

  49 shared

• Ramit Lamba

  University of California, Davis

  36 shared

• John P. McGahan

  University of California, Davis

  26 shared

• Thomas W. Loehfelm

  University of California, San Diego

  25 shared

• Souvik Sarkar

  Datta Meghe Institute of Medical Sciences

  16 shared

• Christoph Troppmann

  12 shared

• Guobao Wang

  Tongji University

  12 shared

• Machelle Wilson

  University of California, Davis

  11 shared

Labs

• Abdominal ImagingPI

Awards & honors

• Roscoe E. Miller Best GI Paper Presentation Award (2015)
• Rush Rees Academic Scholarship, University of Rochester (199…