Detection of Retinal Hemangioblastomas in von Hippel–Lindau Disease Using Three-Dimensional Arterial Spin Labeling MR Imaging at 3T

During the same MR imaging scan that revealed these findings, we also performed 3D-ASL (3D fast spin-echo acquisition with spiral readout, pseudocontinuous ASL (pCASL); repetition time/effective echo time, 4590/10.5 ms; field of view, 240 × 240 mm2; labeling time, 1450 ms; post-labeling delay, 1525 ms; slice thickness, 4.0 mm; number of slices, 32; and number of excitations, 2) using a 3-Tesla MR imaging (3-TMRI) system (Discovery MR750, GE Healthcare, Milwaukee, WI, USA) with an eight-channel phased array coil. The two mass lesions showed increased blood flow on 3D-ASL. In addition to these lesions, the 3D-ASL clearly demonstrated a region of increased blood flow in the left retina (Fig. 1A), which was barely identified on Gd-T1WI (Fig. 1B). Six months later, the two lesions in the right cerebellar hemisphere and medulla oblongata showed no enlargement on MR imaging. The masses may have been hemangioblastomas, although histopathological examination was not performed for confirmation. Fundoscopy revealed that the lesion in the left retina was a hemangioblastoma (Fig. 1C). To the best of our knowledge, this is the first report to describe the value of 3D-ASL in detecting retinal hemangioblastomas. ASL using 2D-echo planar imaging may result in image distortion, due to air in the paranasal sinuses, and therefore, cannot be used for the detection of masses in the orbital region.3 In this case, we used pCASL with 3D fast spin-echo imaging with spiral readout to cover the entire head and decrease distortion, in addition to the high magnetic field at 3T for a higher signal-tonoise ratio than that at 1.5T. We believe that 3D-ASL at 3-TMRI may allow the detection of retinal hemangioblastomas. The conventional Gd-T1WI allowed limited detection of retinal hemangioblastomas, while 3D-ASL clearly demonstrated the lesion, which indicated increased blood flow. These findings suggest that 3D-ASL can aid in the CLINICAL IMAGE