New York Rangers goalie Mike Richter has experienced little change in his battle with postconcussion syndrome the past three-plus weeks and was ruled out for the season Thursday.

Richter visited team neurologist Karen Johnston in Montreal on Monday, the Newark Star-Ledger reported in Tuesday's editions, as he tries to let his brain heal from a second concussion in eight months. Appointments with Johnston are part of the protocol Richter is following in his rehab.

Since suffering the latest concussion during a 5-2 victory over Edmonton on Nov. 5, the Star-Ledger reported Richter has been waiting to go 48 hours without experiencing postconcussion symptoms such as fatigue or lightheadedness. He has not arrived at that two-day period yet.

Richter's visit to Johnston was scheduled over the weekend after he went through last week without feeling any significant improvement, the newspaper said. His struggle to get well has meant a stoppage of many of his normal activities, including workouts, which has left him with a lot of time on his hands.

"With Ricky, there's no change yet," Rangers coach Bryan Trottier told the Star-Ledger. "But we're encouraged that he's going to be re-evaluated. Hopefully, he can start to work out, because he's getting a little anxious."

Dan Blackburn has taken over the No. 1 goaltending duties in Richter's absence and has started 15 consecutive games. He has lost his past three starts to slip two games under .500 (7-9-3), and allowed seven goals on 60 total shots in back-to-back 4-1 losses over the weekend.

Blackburn got the day off Monday along with the rest of the team and will likely be back to work against the Chicago Blackhawks on Wednesday night at Madison Square Garden.

"There's no doubt in my mind that as every game goes on, it's going to be a little more taxing," Trottier said. "But I think Danny's done a superb job holding the fort."

Information from The Associated Press was used in this report.