No one would dispute that women’s healthcare has advanced significantly in both technological discoveries and clinical applications during the past 40 years. The first mammography machine, developed in 1966, was nothing more than a glorified tripod supporting an X-ray camera. The emergence of commercial use of obstetrical ultrasound came about during the 1960s as well. Today, healthcare facilities use a host of machines, interpret numerous findings from breakthrough software, and maintain compliance through various programs, including the Mammography Quality Standards Act of 1992. When it comes to breast and uterine health today, it would appear that we’ve come a long way, baby … but have we?

Breast Cancer Screening: The Latest and Greatest
Mammography technology—considered the gold standard for screening and diagnosing new cases of breast cancer—proves that early detection saves lives. In its “Cancer Facts and Figures 2004,” the American Cancer Society (ACS of Atlanta) estimates 215,990 new breast cancer cases will be reported this year, compared to 50,840 and 80,660 for uterine and lung cancer cases, respectively. Take note that lung cancer kills more women than breast and uterine cancers combined; the ACS predicts an estimated 68,510 lung cancer deaths, 40,110 breast cancer deaths, and 7,090 uterine cancer deaths in 2004.

The fact that more than 200,000 new cases of breast cancer will be diagnosed in this country is bittersweet. On one hand, with early detection, the 5-year survival rate is 95%. Yet, roadblocks remain to quality healthcare for many women, ranging from uncertainty about screening options to lack of insurance for others. Fortunately, the women who do seek mammography are being tested at an excellent point in the evolution of women’s health history. Today’s mammography systems emphasize patient comfort and provider ergonomics while seeking to minimize callbacks, biopsies, and false-positives or false-negatives.

The new Mammomat NovationDR full-field digital mammography (FFDM) system from Siemens Medical Solutions (Malvern, Pa) offers digital screening, diagnostics, and biopsy capabilities in one unit. This fully digital system—based on the analog Mammomat Nova 3000—can reach close to 100% utilization in clinical practice.

“Siemens has installed more than 4,000 of the Nova 3000 since the late 1990s,” says Joanne Scott-Santos, manager of women’s health at Siemens. “The difference with the Nova is that it’s built with digital in mind. Many of the exclusive features on the digital Novation are the same as on the analog, such as the pivoting bucky and OpComp, to compress no more than necessary.” OpComp is a Siemens patient-comfort feature for gentle compression, and it automatically senses that the breast is compressed sufficiently to ensure that good image quality is obtained. Mean-while, the pivoting bucky (where the breast is positioned during the test) is a patient-size feature: a dual design for easy switching between 18 x 24 cm and 24 x 30 cm so it can fit small- and large-breasted women.

The Mammomat NovationDR full-field digital mammography system from Siemens Medical Solutions offers digital screening, diagnostics, and biopsy capabilities in one unit.

Four years ago at RSNA, Siemens had a strong digital system that was based on amorphous silicone. The company refocused its digital mammography plans and switched to amorphous selenium, which developers found more favorable for digital mammography.

“Another new feature for the Novation is the full-field digital flat panel made of amorphous selenium detector. It’s better because it has a smaller pixel size, and theoretically, a smaller pixel size produces better image quality,” Scott-Santos says. “Our product portfolio consists of cutting-edge technology—through screening mammography to MR. We have a product to address every stage from screening, diagnosis, treatment, and, hopefully, a cure. Siemens is very dedicated to furthering and improving on women’s health issues.”

Siemens is currently working with R2 Technology (Sunnyvale, Calif) and CADx (Nashua, NH) to incorporate computer-aided diagnosis (CAD) as an add-on system for its digital mammography unit.

The MammoReport Plus workstation for mammography diagnosis is equipped for CAD applications, offers full spatial resolution, and allows users to switch between eight-view mammography studies in less than 1 second.

“It’s been developed for mammography with input by physicians in European screening programs in the Netherlands and Sweden,” Scott-Santos says.

Further, the optional digital workup tool, Opdima—currently the only spot digital mammography device cleared by the FDA—is available with either the analog Nova 3000 or the new NovationDR for enhanced views and stereotactic biopsies. “Opdima is used for diagnostic workups,” she adds. “It can resolve as many as 20 line pairs, [which aids] in helping with characterizations of lesions. Physicians see a quicker procedure time realized with digital. For biopsies, it’s almost real-time viewing.”

GE Healthcare’s (Waukesha, Wis) newest addition to its mammography line is the Senographe DS, an FFDM system that performs screening, diagnostic, and interventional procedures from one location.

The flat-panel mammography system, which has received FDA clearance, features advances in image quality, patient comfort, and provider ergonomics, and it gives the radiologist the ability to contrast and highlight suspicious areas. Newer technology, such as the Premium View, increases productivity by allowing the radiologist to highlight the view of the breast, from the skin line to chest wall, all in one image window.

“The DS technology features a rede-signed image chain and X-ray tube, and it enables crisper, more defined images,” says Jean Hooks, general manager of global mammography at GE Healthcare. “Another benefit is being able to position the patient correctly. The fully automated Senographe DS allows the technologist to work with adjustable speeds and benefit from fast image display.”

The Intera Achieva 3T from Philips Medical Systems performs a breast MR scan in less than 15 minutes.

Another new development is the Seno Advantage, a multimodality workstation allowing physicians one access point to more than 30 breast cancer–detection tools and applications, as well as one central location to review a patient’s MR, ultrasound, mammogram, or past mammograms. The Seno Advantage uses the AW 4.2 platform software and includes two high-resolution grayscale monitors for breast imaging; a third monitor is used to access the hospital’s PACS/RIS to pull up the patient’s information.

“Its best feature is the ability to leverage all of the tools available for the radiologist to make the most accurate diagnosis,” Hooks says. “Radiologists work in an environment with tools and data, and they need to manipulate the images at hand for the best diagnoses. For the first time, this system allows for the merging of all data sources.”

Taking Precedence: Minimally Invasive Techniques
For all of its advances, mammography is not 100% accurate. Breast ultrasound and MRI have quickly found a niche as the most effective complementary tools for breast health. Recently, the ACS suggested ultrasound for screening women with dense breast tissue, which is difficult to evaluate by routine mammogram. The ACS also recommended MRI because of its effectiveness at aiding in diagnosis.

The ACS reports that more than 1.2 million breast biopsies are performed annually in the United States, and approximately 80% of the biopsies are negative. With the current variety of minimally invasive techniques, a doctor who detects something suspicious during a mammogram does not necessarily need to send the patient to the operating room. Breast surgeons are now using ultrasound and MRI during image-guided needle biopsies instead of an open surgical biopsy. This technology drastically reduces the number of patients who must endure the emotional pain and medical risk of an open surgical incision.

“Ultrasound is not as good as mammography for breast screening, but it is better as a way to isolate a lesion in order to do a breast biopsy or drainage of a cyst. Once you know where the lesion is, ultrasound is superb,” explains Lars Shaw, director of worldwide general imaging marketing for Siemens’ Ultrasound Division. “You don’t have to expose the patient to any more radiation, and it can be performed by one clinician. Also, ultrasound can help you characterize the lesion and determine whether there is blood flow into the lesion.”

As he holds the transducer on the breast, the physician can view images in real time while inserting the needle. He can see the

needle appear in the ultrasound image, and, in turn, puncture the lesion. One product for such biopsies is Siemens’ Acuson Sequoia 512, which offers a 15 MHz transducer, allowing the clinician to switch between very high to lower frequencies among small- and large-breasted women. The latest option is the Paragon Release, a collection of workflow and performance enhancements that significantly impact usability, functionality, and reliability. Included in this release are tissue contrast enhancement technology and Spatial Compounding Plus, specific breast imaging improvements that increase near-field sensitivity, detail resolution, and overall image uniformity. The new option is compatible with the Acuson Sequoia 512 platforms.

Another ultrasound benefit is that it might aid in maintaining the breast health of women under age 40. In the same way that CAD with digital mammography is pioneering new methods in early breast cancer detection for younger women, ultrasound is changing the way many women are screened. For example, younger women typically have dense breast tissue that appears white or gray during a mammogram. Ultrasound can help distinguish among calcifications and other tissue abnormalities.

“The gold-standard method for screening is a mammogram, which works well because it can scan the entire breast at once, allowing a complete view of the entire breast and any associated suspicious areas quickly,” Shaw says. “But with a dense breast, a mammogram can look white or one uniform level of gray. Ultrasound can be an adjunct to mammography or for when mammography isn’t definitive. An ultrasound exam can help with dense breasts because you can use different ultrasound frequencies to differentiate within the tissue to see any irregularities or cysts. With the 15L8 transducer, we can use frequencies down to 8 MHz to penetrate the dense breast tissue. Ultrasound spots irregular, suspicious shapes and can even see whether there is blood flow to the suspicious area or calcifications around it.”

One new development in the integration of mammography and ultrasound is a full-field breast ultrasound (FFBU) system from U-Systems Inc (San Jose, Calif). The system is designed to image the whole breast and immediately deliver results to physicians in a standardized format, making it possible to perform high-volume, cost-effective ultrasound imaging on women with dense breasts. Siemens provides the ultrasound engine of the Sonoline Antares ultrasound system, which is integrated into the FFBU from U-Systems, as part of an agreement in February.

“The system complements mammography as an aid for radiologists in the detection and diagnosis of breast cancer,” Shaw explains. “It performs an automated ultrasound on the breast and also performs a mammogram. You place the mammogram X-ray up next to the ultrasound image for comparison. You can literally touch the suspicious place on the

X-ray, and it automatically coordinates the lesion on the ultrasound.”

Today’s Ultrasound: Not Your Mother’s Procedure
Beyond its advances in promoting breast health, ultrasound is more than a tool for prenatal care. “The uterus is a very important organ to look at with ultrasound for many things, including cysts, fibroids, or cancerous lesions,” Shaw says.

For example, uterine fibroids offset the “natural” shape of the uterus, and ultrasound is a noninvasive diagnostic alternative for women who suffer the chronic pelvic pain and heavy menstrual bleeding caused by fibroids.

The past several years have seen an increase in uterine fibroid embolization (UFE), which is a welcome discovery for the millions of women who have experienced a myomectomy or hysterectomy. UFE works by selectively blocking the arteries to the fibroids—in essence, cutting off the blood supply to the fibroids by placing a catheter into the uterine arteries and injecting polyvinyl alcohol. Ultrasound, and MRI in some cases, is used during pretreatment and postprocedure to determine whether the fibroids are gone for good.

Though promising, UFE has conflicting medical accounts. Advocates champion the future of this alternative for fibroid treatment; yet, others worry about radiation exposure during the X-ray–guided procedure, the long-term side effects of polyvinyl alcohol to area organs, risk of infection and ovarian damage, and sexual side effects.

MRI-guided focused ultrasound, still in its infancy, appears to be the first completely noninvasive therapy for fibroids. In this new method, a thermal beam locates the fibroid and applies intense heat to cut off the blood supply.

MRI: A Costly Yet Highly Sensitive Tool
“At present, MRI is number three for diagnostics,” says Srirama Swaminathan, PhD, MR clinical scientist for the mid-Atlantic region at Philips Medical Systems (Cleveland). “Regard-less of a woman’s age group or risk category, a patient’s first choice is the screening mammogram, and if something suspicious is found, an ultrasound is next and then an MRI exam.”

Philips recently introduced the Intera Achieva series of 1.5T and 3.0T. This ultrafast MR scanner offers a FreeWave data acquisition system with scalable 32-channel architecture and MobiScan, a total-body imaging system that offers an unlimited field-of-view in a single pass.

“Faster, reduced scan times translate to less time for the patients in the scanner and, hence, improved comfort. Keeping patient comfort in mind, we have made the breast MR scan less than 15 minutes with a higher image resolution sufficient to detect even a submillimeter lesion,” Swaminathan says.

On the horizon at Philips is MR elastography (MRE), which is an age-old technique of screening for something suspicious in the breast by exploiting the elastic properties of the tissue in terms of real physics.

“MRE, which could be added into existing MR screening, sends in energy with 60-Hz frequency waves that excite the breast tissue. This excitation is phase-locked with an MR sequence that measures the phase changes in all three directions, which then can be transformed into elastic values measured in kilo Pascals,” Swaminathan explains. “In general, tumors are stiff and have higher values, with cysts being elastic with very low values. The 60-Hz vibrations on the breast are created by a transducer that we position in such a way that it touches the breast—not compressing it, but just enough to make waves.”

The data is collected and processed on an off-line workstation. The report details the elastic property of the tissue and whether the elastic property is consistent with a benign or malignant tumor. By developing a tool for MRE, Swaminathan—along with Philips colleague Ralph Sinkus—hopes to clarify how elastic properties are unique to every lesion. MRE is still in research and development, but clinical studies are under way at St Barnabas Ambulatory Care Center (Livingston, NJ) as well as in Europe.

Swaminathan also works at the Breast Center at St Barnabas, the nation’s largest outpatient facility for breast MRI exams, where staff members are exploring MR-guided biopsy methods.

“At St Barnabas, we’re focusing on creating a comprehensive breast MR protocol that combines ultrafast diagnostic exams using Sense technology, diffusion-weighted imaging, and MRE to improve specificity. MR is 35% to 60% specific with a sensitivity of about 90%; we’re working to have the specificity of MR set to the 90% level,” he says. “We are trying to create MR as a one-stop shop, including MR-guided biopsies for patients instead of having to undergo a lot of procedures. With the current level of sensitivity and improved specificity, we hope to reduce unnecessary biopsies.”

“There have been two main approaches to breast MR,” explains Helmuth Schultze-Haakh, PhD, Siemens’ MR collaborations manager. “The Europeans looked primarily at the dynamic behavior after bolus contrast injection of gadolinium, the common MR contrast agent. The US approach has been looking at the structure of the lesions before and after contrast injection. This requires higher spatial resolution, which typically takes longer acquisition times.”

MR-guided breast biopsies include wire placements, core biopsies, and vacuum-assisted breast biopsies, the latter of which essentially excise a portion of tissue and can possibly remove smaller lesions. These procedures are usually done with X-ray, he adds.

Another company pioneering safer, noninvasive imaging techniques is Dilon Technologies Inc (Newport News, Va). The Dilon 6800 uses breast-specific gamma imaging to view the metabolic activity of the breast with a small-field-of-view gamma camera. In clinical trials, the camera could see lesions as small as 3 mm, and with its high specificity, helps distinguish malignant from healthy tissue.

Elaine Koritsas is a contributing writer for Medical Imaging.