Asymptomatic large T2 high-signal pontine lesions that are different from ischemic rarefaction.

BACKGROUND: We encountered asymptomatic large T2 high-signal pontine lesion (PL) with peachlike configurations on magnetic resonance imaging. The objective of this study was to determine the pathogenic factors for such PLs and to differentiate PL from ischemic rarefaction.

METHODS: We compared the clinical backgrounds of 37 patients with PL and 100 patients without PL, including conventional atherosclerotic risk factors, chronic kidney disease (CKD) defined as an estimated glomerular filtration rate less than 60 mL/min/1.73 m(3), and the degree of supratentorial deep white matter hyperintensities (DWMH). The chronologic alternations in PL were also reviewed.

RESULTS: Patients with PL had a much higher incidence of diabetes mellitus (DM) and CKD as compared with patients without PL: 54% versus 15% for DM (P < .001) and 57% versus 29% for CKD (P < .05). PL did not necessarily accompany DWMH and its degree did not correlate with PL. Further analyses showed that patients with PL without DWMH had a much higher incidence of DM and CKD as compared with patients with DWMH without PL: 85% versus 6% for DM (P < .0001) and 85% versus 50% for CKD (P < .05). Chronologically, PLs expanded, shrunk, or fluctuated in size in 5 patients with DM and CKD.

CONCLUSIONS: We demonstrated that DM and CKD are important for PL and that the backgrounds of PL were inconsistent with DWMH. These results and the chronologic alternations in PL suggested that metabolic factors other than ischemic rarefaction played important roles in the development of PL.