The age of the child at symptom onset is important, where girls <6 and boys younger <9 are most likely to show a central nervous system abnormality and therefore should be screened with MRI [104,106-108]. For girls 6 to 8 years of age, the likelihood of identifying a central nervous system lesion is lower, estimated between 2% to 7%, and neoplastic in 1% [104,109]. The need for routine central nervous system imaging is controversial and requires careful clinical consideration [107,110]. CT Sella CT provides the ability to evaluate the overall size and structure of the sella turcica but offers little in the way of intrasellar and parasellar soft-tissue detail. Larger lesions in the suprasellar cistern can be identified (ie, germinoma, astrocytoma, arachnoid cyst), as well as gross morphological alterations in the configuration and appearance of the ventricles, such as in the setting of hydrocephalus [111]. CT with IV contrast may highlight a solid mass but is rarely indicated as an initial screening examination. CTA Head CTA may be part of operative planning or image guidance; however, CTA is not routinely used for initial evaluation of precocious puberty [20]. MRA Head There is no relevant literature regarding the use of MRA in the evaluation of precocious puberty. MRI Sella MRI is the preferred imaging modality to evaluate the hypothalamic-pituitary axis and parasellar regions with its superior depiction of parenchymal tissue [105,112]. Gadolinium-based contrast adds additional benefit in characterizing lesions. Small pituitary lesions, such as adenomas and Rathke cleft cysts, may be occult without postcontrast sequences. Contrast-enhanced MRI also discriminates between nonenhancing hypothalamic hamartoma and an enhancing astrocytoma. MRI with IV contrast may only be performed for use in operative guidance and should not be considered as a first-line imaging test.
Neuroendocrine Imaging. The age of the child at symptom onset is important, where girls <6 and boys younger <9 are most likely to show a central nervous system abnormality and therefore should be screened with MRI [104,106-108]. For girls 6 to 8 years of age, the likelihood of identifying a central nervous system lesion is lower, estimated between 2% to 7%, and neoplastic in 1% [104,109]. The need for routine central nervous system imaging is controversial and requires careful clinical consideration [107,110]. CT Sella CT provides the ability to evaluate the overall size and structure of the sella turcica but offers little in the way of intrasellar and parasellar soft-tissue detail. Larger lesions in the suprasellar cistern can be identified (ie, germinoma, astrocytoma, arachnoid cyst), as well as gross morphological alterations in the configuration and appearance of the ventricles, such as in the setting of hydrocephalus [111]. CT with IV contrast may highlight a solid mass but is rarely indicated as an initial screening examination. CTA Head CTA may be part of operative planning or image guidance; however, CTA is not routinely used for initial evaluation of precocious puberty [20]. MRA Head There is no relevant literature regarding the use of MRA in the evaluation of precocious puberty. MRI Sella MRI is the preferred imaging modality to evaluate the hypothalamic-pituitary axis and parasellar regions with its superior depiction of parenchymal tissue [105,112]. Gadolinium-based contrast adds additional benefit in characterizing lesions. Small pituitary lesions, such as adenomas and Rathke cleft cysts, may be occult without postcontrast sequences. Contrast-enhanced MRI also discriminates between nonenhancing hypothalamic hamartoma and an enhancing astrocytoma. MRI with IV contrast may only be performed for use in operative guidance and should not be considered as a first-line imaging test.