[N-isopropyl I-123 p-iodoamphetamine single photon emission computed tomography of herpes simplex encephalitis]

Two patients with herpes simplex encephalitis were studied with N-Isopropyl I-123 p-Iodoamphetamine (IMP) single photon emission computed tomography (IMP-SPECT) and X-ray computed tomography (CT). In both cases the affected temporal lobes showed an increased IMP uptake. In case 1, the initial increased IMP uptake decreased as symptoms and CT findings improved. In case 2, the increased IMP uptake was shown at the time of symptoms progressed, while CT had no abnormal findings. IMP uptake is sensitive for its demonstration of inflammatory processes of herpes simplex encephalitis.