Westford’s NetScout Systems Inc. said third-quarter net income rose 11 percent to $11.14 million, or 26 cents per share, from $10.03 ­million, or 24 cents, a year earlier. Revenue climbed to $91.57 million. The results topped analysts’ estimates of 35 cents on $90.63 million in revenue. For fiscal 2013, NetScout, which offers technology services for network and service delivery problems, raised its forecast, citing solid nine-month ­results. CEO Anil Singhal said the company was “pleased to continue our double-digit growth rates.’’