Detection of Adrenocorticotropin-Secreting Pituitary Adenomas by Magnetic Resonance Imaging in Children and Adolescents with Cushing Disease

Section on Endocrinology and Genetics, Developmental Endocrinology Branch, National Institute of Child Health and Human Development, National Institutes of Health, Building 10, Room 10N262, 10 Center Drive, MSC 1862, Bethesda, Maryland 20892-1862, USA.
Journal of Clinical Endocrinology & Metabolism (Impact Factor: 6.21). 10/2005; 90(9):5134-40. DOI: 10.1210/jc.2004-1778
Source: PubMed


We recently showed that pre- and postcontrast spoiled gradient-recalled acquisition in the steady-state (SPGR) was superior to conventional pre- and postcontrast T-1 weighted spin echo (SE) acquisition magnetic resonance imaging (MRI) for the diagnostic evaluation of pituitary tumors in adult patients.
The present investigation assessed the use of SPGR vs. SE-MRI in the diagnostic evaluation of ACTH-secreting tumors in children and adolescents with Cushing disease.
Data were analyzed retrospectively from a series of patients seen over 7 yr (1997-2004).
The setting for this study was a tertiary care referral center.
Thirty children with Cushing disease (13 females and 17 males with a mean age of 12 +/- 3 yr) were studied.
Imaging results were compared with surgical and pathological findings and the clinical outcome.
Twenty-eight patients had microadenomas, and two had macroadenomas; the latter were identified by both MRI techniques. Precontrast SE and SPGR-MRI identified four and six of the microadenomas, respectively. Postcontrast SPGR-MRI identified the location of the tumor in 18 of 28 patients, whereas postcontrast SE-MRI identified the location and accurately estimated the size of the tumor in only five patients (P < 0.001).
We conclude that conventional MRI, even with contrast enhancement, mostly failed to identify ACTH-secreting microadenomas in children and adolescents with Cushing disease. Postcontrast SPGR-MRI was superior to SE-MRI and should be used in addition to conventional SE-MRI in the pituitary evaluation of children and adolescents with suspected Cushing disease.

    • "Although the sensitivity of conventional MRI has been described as suboptimal in patients with CD[20,47], a much smaller proportion of patients had imaging-negative disease in this series. We believe that this reflects the efficacy of a routine integrated MRI protocol that incorporates both dynamic contrast imaging and SPGR[4,41]. Such fastidious examination of high-quality preoperative MRI images may reduce the proportion of imaging negative disease to less than 10 %[22,63]. "
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    • "Dynamic contrast MRI has been reported to provide a diagnostic advantage for selected cases of small microadenomas and is recommended if standard pituitary MR imaging is negative [19]. Spoiled-gradient recall acquisition with thin-slice imaging has also been reported to substantially improve imaging resolution and the diagnosis of small microadenomas [20]. "
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