SPECT imaging of para-axial neurofibromatosis with technetium-99m DTPA.

Single photon emission computed tomography (SPECT) was used to study uptake of technetium-99m diethylenetriaminepentaacetic acid ([99mTc]DTPA) by para-axial neurofibromas in 13 patients. SPECT imaging led to better resolution of uptake in nine instances and detection of 12 lesions unsuspected on planar imaging (PI). Two false-positive instances and one false-negative instance of uptake are described. The planning of the surgical approach and placement of graft material for spinal fusion was assisted by SPECT in two patients. One patient with disability secondary to recurring abdominal pain had detection of the causative lesion by SPECT and subsequent relief of her symptoms following excision of the tumor. SPECT imaging of soft-tissue tumors of neurofibromatosis appears to have potential use in preplanning surgery on structural or cosmetic lesions, in the detection of occult lesions, and the monitoring of patients with neurofibromatosis at regular intervals.