After surgery to remove a tumor from his brain, Arno Knapen often found himself confused and frustrated.
On one frightening trip to a hardware store, he remembers sitting in the parking lot with no idea of how to get home. Another time, he couldn't recall what a paper clip is called.
"It was really scary," Knapen said of that period. "I really didn't know what was going to happen to me."
Then Knapen started visiting River Legacy Parks, where Mother Nature and "macro" photography helped nurse him back to health. At the north Arlington nature area, the 50-year-old American Airlines pilot forced his usually agile mind to focus through the lens of his camera as he snapped thousands of images of insects and wildlife.
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His photos now appear on a bookmark that the River Legacy Foundation is using as part of its annual fundraising campaign. More will be on display in an exhibit planned for late March.
Knapen says sharing the photos is his way of thanking a place where he found sunshine when his thoughts were dark and cloudy.
"The park gave me inner peace, put me at ease, made me see nature, discover things around me," Knapen, a native of Holland and a former fighter pilot, wrote. "The camera gave me the incentive to master this complex little piece of equipment and force my noggin to work as it used to. River Legacy was an almost daily habit in that time."
Kristi Payne, a communications assistant at River Legacy, said the tale of Knapen's journey contains a powerful message.
"I felt that his story really captured the essence of what we do at River Legacy and why we need to continue to preserve the parkland," Payne said.
Twists and turns
In late summer 2008, doctors removed a type of benign tumor called a hemangioblastoma from Knapen's cerebellum. With plenty of rest, he said, they expected him to recover.
But as fall turned to winter, Knapen, who also was going through a divorce, had problems. He often forgot the simplest things, which in turn angered him.
"I found myself in the parking lot at Home Depot unable to remember how to get home," he said. "My entire focus had been on why I needed to go to the store. But once I got there, I forgot everything else. I was sitting in the car and I could remember being a fighter pilot and doing the twists and turns in the air.
"But I couldn't remember the way home."
Another time, he couldn't recall the name of an office supply that holds pages together. A woman watching him struggle finally leaned in and said loudly, "We call that a paaa-perrr clip," as if he were a small child.
Knapen said his doctor was puzzled by what was happening to him.
A physician not related to the case, Dr. Samuel Barnett, assistant professor of neurological surgery at UT Southwestern Medical Center at Dallas, said that since the cerebellum controls motor coordination, memory lapses after this type of surgery are hard to explain.
As brain tumors go, Barnett said, hemangioblastomas "are relatively less common, but they're among the most common in the cerebellum."
Knapen eventually sought the help of a neuropsychiatrist for his postsurgical troubles. He also turned to sudoku, word search puzzles and photography, an old friend he hadn't seen much since high school.
"The doctors said you need to work, work, work your brain," he said. "So that's what I did."
Figuring it out
With a camera, as in the cockpit, the operator has to make complex choices, like aperture, shutter speed and angle.
So Knapen bought a new camera -- one with all the bells and whistles, not a simplified model for taking quick snapshots -- and headed toward River Legacy Parks. He had been drawn there during long walks and bicycle rides earlier in his recovery.
"Initially, I couldn't figure out how to work the darn thing," he wrote of the camera, "but I got better and better by spending hours in and around the park trying to find things and trying to figure out how to best record them."
The images he recorded are colorful and clear. Many are of insects on flowers. His favorite shows dewdrops on the wings of a dragonfly. Another depicts a caterpillar's fuzzy body as it crawls along a blade of grass.
Eighteen months after surgery, following extensive tests, he returned to the air in January 2010. Afterward, Knapen, who flies international routes for American, began taking pictures at a city plaza in South America where residents congregate to play chess.
Those photos, in contrast to his nature shots, are crisply black and white. But both kinds draw the viewer in and invite close study of the subjects' faces and other details.
Knapen will never forget his time in the woods and fields of River Legacy.
In the first months of 2009, it was a beautiful place to be, he said.
"I would just go sit in the sun," he said. "The spring flowers were coming out. It changes constantly, and there's always something new. It's really an amazing ecosystem in there."
Patrick M. Walker, 817-390-7423