His office every Monday afternoon is his no-frills red minivan, strewed with map books because he's prone to getting lost. Into the back seat are tossed files for the patients of the day. Onto the front seat is heaved his zippered black bag. The shoulder-strap medicine cabinet is filled with syringes, bandages and ample doses of homespun wisdom. Back when "doctors were doctors," as Henry Wieman says, not much else was needed.

Maybe that's still the case. Each time his van leaves the Fort Lincoln Family Medical Center on Bladensburg Road in Prince George's County, Wieman is the slightly rumpled personification of a beloved American institution: the doctor's house call. It was declared dead awhile back, prematurely it seems. For in the age of impersonal, high-tech medicine, the house call is coming back.

Its revival is partly a backlash against that technology. But the demands of a rapidly aging population are the stronger force. Elderly people whose frailties essentially confine them to bed cannot come into the office for appointments -- at least not without complicated arrangements for wheelchair vans or ambulances, as well as physical and emotional trauma.

"You simply can't take care of an elderly or chronically ill person without being able to make house calls," says John Burton, director of the geriatric medicine division at Johns Hopkins University Medical School. The school requires undergraduates and training residents to spend up to two years doing home visits. "It's a very powerful learning arena."

According to the American Academy of Home Care Physicians, slightly less than 5 percent of the country's doctors regularly make house calls. Several hundred, though, do nothing but that, and, increasingly, others may follow. With a healthy bump last year in the amount Medicare pays doctors for traveling to patients, preliminary statistics indicate that house calls jumped 25 percent in 1998. Before 1998, notes academy President George Taler, nurses were reimbursed more than physicians for visiting a person's home.

As the new director of long-term care at Washington Hospital Center, Taler soon will launch a house-call service geared primarily toward older people. "The information you get from scanning their environment can tell you a great deal," he says. Social and economic issues surface more readily at home. People behave differently -- and confide more.

This decidedly back-to-the-future approach fits Hank Wieman well. A family practitioner turned geriatrician, he's given to sayings such as, "It's not the mileage, it's the tread wear," which pithily sums up his attitude about age. He regards his elderly patients as fascinating living history and finds them as likable as they seem to find him. "They always think you're young," he laughs. He is 52.

Although connected to the geriatric group at the District's Providence Hospital, Wieman works out of the small strip shopping center where the Fort Lincoln clinic is located. A wall map there is pierced with 36 pins marking his house call stops, mainly in Prince George's and Northeast Washington. He rotates through several people each Monday, spending up to an hour with each. Some home-care physicians carry portable diagnostic equipment that rivals that in any office. Wieman does not even have a cell phone.

Two weeks before Walter Gordon turns 100, Wieman knocks again on the door of his D.C. row house. Gordon's wife (a week from 90) greets him warmly, and with her and a daughter following, the doctor hikes up to a second-floor bedroom. Wieman sits where he can in the small room, which is on the bed. His patient, wearing navy-striped pajamas and an expressive, totem-pole face, sits silently in a corner recliner. Bed and recliner -- the two landmarks of a declining man's shrinking world. Gordon no longer can walk down the stairs, which no longer have a railing. This will have to do.

Daddy fell again yesterday, says his daughter, wedged himself between his chair and the dresser as he tried to stand up. Plus, she adds, his stomach won't hold food much, so he's still not really eating.

Wieman takes it all in as he assesses Gordon's strength, gauges whether his depression is any better, talks baseball briefly, delivers a mild lecture about how best to eat and writes a prescription to settle the stomach.

And then, before he goes, this contemporary Marcus Welby gets down on a knee and trims his patient's toenails.

CAPTION: Geriatrician Henry Wieman, left, examines Emma Johnson as her husband, Leslie Johnson, waits.

CAPTION: Henry Wieman examines Walter Gordon, 100, during a house call to Gordon's Washington home. Doctors' house calls, which had virtually disappeared, are increasing, partly because many elderly patients find it difficult to travel from their homes to medical offices. Story on A15.(Photo ran on page A01)