The Woodland Hills biosensor company SPO Medical Inc. reported its gross revenues increased 103 percent during 2006. Revenues for the entire year stood at $3.7 million, compared to $1.8 million in 2005. Revenues for just the fourth quarter increased 99 percent to $1.9 million, the company said. SPO credited the increased to the popularity of its PulseOx 5500 and Check Mate spot-check finger pulse oximetry monitors.