Hypoglycemia MRI
|
Hypoglycemia Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Hypoglycemia MRI On the Web |
|
American Roentgen Ray Society Images of Hypoglycemia MRI |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];{AE}} Mohammed Abdelwahed M.D[2]
Overview
MRI scan is helpful in the diagnosis of insulinoma in the case of failed CT. It shows enhancement. MRI has better sensitivity than CT scan. It is still considered as the second line of investigation due to cost and availability. Insulinoma shows low intensity on T1 weighted and high intensity on T2 weighted signals, having better visualization on T1 and T2 weighted images with fat suppression.They exhibit typically homogenous enhancement when small and ring enhancement when more than 2 cm. A similar pattern is seen in metastatic lesion as of primary tumor.
MRI
- MRI scan is helpful in the diagnosis of insulinoma in the case of failed CT.
- MRI is superior in detecting insulinoma and has greater sensitivity. The sensitivity has increased to 94%.
- Findings of MRI suggestive of insulinoma include:[3][1]
- T1 typically shows enhancement, although contrast enhancement may not improve tumor visualization.[2]
- T1 and T2 relaxation times for islet-cell tumor-like insulinoma has lower protein and proton concentration time. [3]
- Homogeneous enhancement is exhibited commonly in insulinoma. Enhancement patterns are due to hypervascularity.[3]
- Metastatic lesions in lymph nodes are homogeneous when small and show ring enhancement if the tumor is more than 2 cm.[4]
References
- ↑ Noone TC, Hosey J, Firat Z, Semelka RC (2005). "Imaging and localization of islet-cell tumours of the pancreas on CT and MRI". Best Pract Res Clin Endocrinol Metab. 19 (2): 195–211. doi:10.1016/j.beem.2004.11.013. PMID 15763695.
- ↑ Pongprasobchai S, Lertwattanarak R, Pausawasdi N, Prachayakul V (2013). "Diagnosis and localization of insulinoma in Thai patients: performance of endoscopic ultrasonography compared to computed tomography and magnetic resonance imaging". J Med Assoc Thai. 96 Suppl 2: S187–93. PMID 23590041.
- ↑ Thoeni RF, Mueller-Lisse UG, Chan R, Do NK, Shyn PB (2000). "Detection of small, functional islet cell tumors in the pancreas: selection of MR imaging sequences for optimal sensitivity". Radiology. 214 (2): 483–90. doi:10.1148/radiology.214.2.r00fe32483. PMID 10671597.
- ↑ Noone TC, Hosey J, Firat Z, Semelka RC (2005). "Imaging and localization of islet-cell tumours of the pancreas on CT and MRI". Best Pract Res Clin Endocrinol Metab. 19 (2): 195–211. doi:10.1016/j.beem.2004.11.013. PMID 15763695.