Indeed USA deviates from ICAO:
22.214.171.124 Zeros are not used to precede single-digit runway markings. An optional configuration of the numeral 1 is available to designate a runway 1 and to prevent confusion with the runway centerline.
Source: USA AIP - GEN 1.7 Differences From ICAO SARPs
126.96.36.199 in ICAO SARPs Annex 14 (Aerodromes) is as follows (emphasis ...