(Adds expenses, shipments, background, share price)
Jan 25 (Reuters) - Intuitive Surgical Inc topped analysts' forecasts for fourth-quarter earnings on Thursday, helped by strong demand for its robotic systems used in surgeries.
Intuitive's shares, which hit a record high earlier in the day, fell 1.2 percent in after-hours trading. The stock has already risen 23 percent in 2018 after a 73 percent climb last year.
Sunnyvale, California-based Intuitive has enjoyed a near monopoly in the abdominal surgical robots market since launching its flagship device called da Vinci in 2000.
But the company has in recent months ramped up spending on product development to remain ahead of competition.
Its operating expenses rose 16.6 percent year-over-year to $306.3 million in the quarter ended Dec. 31.
The company shipped 216 da Vinci systems in the quarter, compared with 163 in the prior-year period.
Intuitive reported a net loss of $38.8 million or 35 cents per share in the quarter ended Dec. 31, compared with a profit of $204 million or $1.71 per share, a year earlier.
The loss reflected a $318 million expense related to new U.S. tax laws.
Excluding the expense, the company earned $2.54 per share, ahead of analysts' average estimate of $2.24, according to Thomson Reuters I/B/E/S.
Revenue rose 17.9 percent to $892.4 million. (Reporting by Manas Mishra in Bengaluru; editing by Sai Sachin Ravikumar)