When should cranial magnetic resonance imaging be used in girls with early sexual development?

OBJECTIVE

To determine whether concise parameters can be established in girls who present with signs of early puberty before the age of 8 years, which would help to identify those in whom cranial magnetic resonance imaging (MRI) is indicated.

METHODS

A retrospective chart review was undertaken over a 10-year period from 1992-2002. The two requirements for inclusion in this study were girls who manifested pubertal changes before the age of 8.0 years and who underwent MRI of the brain. The records of 130 female patients with the presumptive diagnosis of precocious puberty (PP) were evaluated. Patients' medical records were reviewed for histories of any reported focal neurological complaint suspicious for intracranial lesions, such as headaches, seizures, or visual disturbances, as well as menses and advanced bone age (>2 SD) compared to chronological age. Seventy-five patients met these criteria and were divided into two groups. Group I consisted of nine patients with abnormal cranial MRI; Group II consisted of 66 patients with normal MRI.

RESULTS

The patients in each group who had one or more of the central nervous system (CNS) signs and symptoms of early sexual development that were evaluated were markedly different. In Group I, 89% (CI 52-99.7%) had positive signs and symptoms that were suspicious for an intracranial lesion. In Group II, 94% (CI 85-98%), 63 of 66 girls, had no CNS signs or symptoms.

CONCLUSION

The use of cranial MRI in the evaluation of girls with early sexual development is excessive. Girls with signs of pubertal development before age 8 years should be evaluated and followed. Those with specific CNS signs and symptoms, menses, and girls with a rapid advance in sexual development should undergo cranial MRI. Using this approach, far fewer patients in our study would have had cranial MRI.