Doctors usually recommend that women older than 40 get yearly mammograms. But if you're planning on calling Northwestern Memorial Hospital's state-of-the-art breast imaging center, grab next year's calendar: The next opening is in May.

The long wait for a screening mammogram is unusual; other hospitals and imaging centers can get you in and deliver results within several weeks.

Moreover, if you detect a lump, you'll be jettisoned to the head of the line. But even then, while the goal at Northwestern's Lynn Sage Comprehensive Breast Center is to see the patient the day after the request, the appointment can be delayed as much as four weeks.

Mammograms aren't perfect, but they can catch pinhead-size abnormalities, which often go undetected in a self-exam. The sooner one is caught, the sooner it can be treated.

The backlog at Lynn Sage, which strives so hard to be patient-friendly that exam gowns are heated, stems from increased demand and a national shortage of breast imaging radiologists, said Dr. Ellen Mendelson, section chief of Northwestern's breast and women's imaging department.

The demand has outstripped supply for several reasons, she said: the recommendation that all women older than 40 get a yearly exam, an aging population, and the use of defensive medicine and fears of litigation.

Lynn Sage, located inside the $500 million Prentice Women's Hospital which opened last October, is the largest single-site breast imaging facility in Illinois and one of the busiest in the nation. Each day, about 400 people call for appointments, and the all-digital center performs more than 65,000 breast imaging exams a year, including diagnostic, ultrasound and MRIs.

Breast imaging radiologists are scarce, however, in part because screening mammography is not historically a high-paying specialty, has been poorly reimbursed and is prone to litigation relative to other imaging procedures, said Mendelson. Consequently, radiologists have turned to other sub-specialties.

Mendelson said the problem will resolve itself by next summer when Northwestern can boost the total number of radiologists from 9 to 12. The hospital is also looking for partnership opportunities to handle the workload, officials said.

But if waiting isn't your thing - and you should never wait if you feel a suspicious lump - here are two ways to get a faster mammogram. Just don't forget your doctor's referral.

-Call around. University-affiliated hospitals are your best bet, but they aren't the only places that offer mammograms. Make sure the center has a radiologist who specializes in breast x-rays. Try to go to the same place consistently so they can compare films. For a list of facilities certified by the Food and Drug Administration, go to www.fda.gov/cdrh/mammography/certified.html, or call the American Cancer Society at 800-ACS-2345.

-Avoid peak season. Everyone tries to get an appointment in October, in part because it's one of two breast cancer awareness months. September and November are also very busy. Try to schedule the appointment during your birthday month or in February.

(Contact the writer: jdeardorff@tribune.com )

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