C-arms are one of the driving technological forces behind the advancement of minimally invasive surgeries. These mobile fluoroscopic imaging systems are precise and accurate devices that allow for less patient discomfort in a variety of surgical and nonsurgical procedures. The minimal invasiveness with the use of C-arms has helped lead to the increase of more cost-effective outpatient care.

Initially used in general surgery or orthopedic applications, C-arms are now described by both manufacturers and users as highly versatile, thanks to the technological advancements made since the original designs. In fact, C-arm usage recently has expanded to include minimally invasive, spinal, general, and orthopedic surgeries; pain management; and cardiac, urology, vascular, and neurovascular applications. According to Wolfram Klawitter, president of the Ziehm C-arm line (Riverside, Calif), “C-arms are the most versatile pieces of equipment that a hospital can buy.”

Dr Narayan Sundaresan, professor of Neuro Surgery at Mount Sinai in New York City, describes C-arms as an “indispensable tool in surgery, [particularly] with the advent of minimally invasive surgery.” C-arms allow Sundaresan, a spine surgeon who has worked with C-arms for more than 13 years, to perform minimally invasive spine surgery by checking the positions of screw and plate placement. The use of this interoperative imaging has become a part of the surgical process; using C-arms is now “almost mandatory,” he says.

Physicians rely on C-arms for precise, accurate, instant information; technicians depend on the explicit information and the easy-to-use technology. Glenn Williams, lead technologist of the emergency and surgical radiology department of the Cleveland Clinic, loves the portability of C-arms, the availability, the ease of use, and the quick “live” results. “I wonder what [we] would do without them,” he says.

The Market Share
The C-arm market consists of several manufacturers, with the top four being Philips Medical Systems (Andover, Mass), the Ziehm C-arm product line (formerly owned by Instrumentarium Imaging Inc), Siemens Medical Solutions (Malvern, Pa), and GE Medical Systems (GEMS of Waukesha, Wis). Each of these companies manufactures a range of C-arms—from basic or compact functionality to high-end, fully functioning equipment.

Philips Medical Systems invented C-arms in 1952 and now manufactures three types, all previously established units that the company continually enhances. The BV Libra, Philips’ basic-level C-arm with a 6- or 9-inch image intensifier, is a lightweight, user-friendly system designed for routine procedures, especially orthopedic and pain-management applications. Philips’ BV Endura C-arm, with a 9- or 12-inch image intensifier, is applicable for routine or specialized procedures.

And the BV Pulsera is the high-end unit, also with a 9- or 12-inch image intensifier, and, according to the company, is designed to handle “more specialized, minimally invasive procedures that help people recover faster.” The Pulsera houses a powerful generator, an advanced rotating anode feature, and such options as vascular or cardio packages. In addition, the Pulsera offers full DICOM capability to interface imaging from the C-arm to the hospital network. All Philips’ C-arms allow for additional options, including memory extensions, extended processing packages, laser-positioning tools, recording devices, high-end monitors, and DICOM interfacing.

Increasing image quality (better monitors, more efficient image intensifiers) and decreasing dosage levels (more powerful images with less radiation) are “consistently the number one priority” for Philips C-arm enhancement, says Dave Melin, director of Philips’ surgical business unit (Bothell, Wash). He adds that the trend with C-arms is to become even more useful; C-arms are “central as a workhorse” within smaller facilities. Customer choice between purchasing a C-arm with cardiac capabilities or building a complete cath lab depends on the size of the facility, the specific customer needs, and, of course, funds. “Financially, [the C-arm] is the best bang for your buck,” Melin claims.

The BV Libra is Philips Medical Systems’ basic C-arm model. With form-fitting handles and a sturdy base, this C-arm offers what Philips calls a “humanware” design.

Clearly, other manufacturers agree. The Ziehm C-arm product line, formerly owned by Instrumentarium Imaging Inc (Milwaukee, Wis) and now pending divestiture from GE Medical Systems, consists of four main C-arm models in the United States. The Ziehm Compact was a pioneer by being the market’s first mobile C-arm without a separate monitor cart, ideal for confined space in operating rooms. The Ziehm 7000, a step up from the Compact, features two monitors and a cart, a small footprint, large dimension, and 45-degree orbital rotation for particular use in pain management and orthopedics. An enhancement of the Compact is the Ziehm Vista, which has greater image quality, radiation dose savings, and optional vascular-feature additions.

Hologic’s Premier Encore mini C-arm offers expanded views of extremities, like shoulders and knees.

On the high-end, the Ziehm Vision is an ideal offering for use in cardiology, urology, neurology, and orthopedics. This model includes the Vision Centre, which is Ziehm Vision’s new touch-screen user interface that is mounted on both the mobile C-arm and the monitor cart. Ziehm’s Klawitter says that the Vision Centre was “designed with the technician in mind,” as neither the C-arm technician nor the doctor needs to walk back to the monitor to see the images. Additionally, a heat unit calculator provides remaining available fluoroscopy time while preventing overheating by automatically adjusting the generator output power. Ziehm Vision also integrates a stationary anode with active cooling. Klawitter says that this active cooling system “outruns any rotating anode.”

Siemens Medical Solutions also has a complete line of C-arms, starting with the SIREMOBIL Compact (L), dubbed on the Siemens Web site as “the clinical all-rounder” for use in general, vascular, and trauma surgery as well as orthopedics. The SIRE-MOBIL Iso-C (LF), with 190 degrees of orbital rotation, uses an isocentric design for precise positioning. Michael Caro, product manager of the surgery division at Siemens, explains that isocentric C-arms are a time-saving, convenient application that could increase throughput potential for physicians. The image intensifier and X-ray tube are placed within the C-arm, rather than at the end, creating minimal need for patient repositioning. With a fixed isocenter in an isocentric C-arm, only the arm needs to be rotated, not the patient. The Iso-C unit concentrates on image quality at minimum dose and also offers DICOM capabilities.

Mount Sinai’s Sundaresan is particularly fond of the highly technical and high-level functioning of the Siemens isocentric C-arm. The interoperative images produced by the Iso-C can be “exported to the surgical navigation system” for image-guided procedures. In fact, he says, the biggest advancement in surgery today is the surgical navigation system that is used in conjunction with the C-arm to produce 3-D images.

Caro adds that the isocentric concept “set the stage for 3-D.” By adding a computer-controlled motor to an isocentric C-arm, the C-arm rotates while 2-D snapshots are taken at regular intervals in a “controlled, precise isocentric fashion.” Those 2-D images are then transmitted to a PC, which calculates a 3-D image. With the SIREMOBIL Iso-C3D, physicians can immediately view “a 3-D world on a 2-D screen” in axial, sagittal, and coronal views as well as any variation of the three. This 3-D technology is ideal for viewing fractures and performing trauma and spinal surgery, and it gives the potential to reduce revision procedures. Additionally, Siemens provides seamless integration for surgical navigation systems or for image-guided surgery.

Despite many changes in ownership through the years, the Ziehm Vision is still one of the top C-arm models on the market.

All Siemens’ C-arms “can be outfitted with the option for cardio imaging,” Caro notes, but the Siemens POWERMOBIL was designed specifically for cardiac, cardio-thoracic, and cardio-surgical imaging. The POWERMOBIL combines the functionality of a fixed cardiac cath lab with the flexibility of a mobile C-arm system, the company says. This model is the highest-powered C-arm, with a larger generator, shorter pulse width, and rotating anode. Caro explains that the power and pulse are used to “stop the motion of the heart, visually.”

GE Medical Systems’ involvement with C-arms began about 4 years ago, when the company purchased OEC (Salt Lake City), a company that had been manufacturing C-arms since the mid-1970s. The OEC C-arm product line is still manufactured by GEMS today, complete with several full-sized C-arm models as well as one mini C-arm model.

In terms of standard-size C-arms, the OEC 7700 Compact+ is a one-piece system with the monitor attached to the C-arm assembly. The Compact+ is designed for simple “point-and-shoot procedures,” says Ryan Hales, product manager at OEC headquarters. If additional image storage, advanced or dynamic imaging, or vascular studies are needed, a customer can choose to add a dual-monitor workstation to this model. For more advanced image processing and more sophisticated vascular applications, the OEC FlexiView 8800 is a suitable system, complete with higher resolution, 1K-x-1K imaging.

For heavier anatomy applications, such as endoscopic studies, spinal procedures, and pain management, GEMS offers the OEC 9800 Plus. According to Hales, this model has a “sophisticated generator that can pulse the X-ray beam [quickly enough] to stop motion,” resulting in very precise images. This “real-time” imaging is ideal for cardiac procedures with the OEC 9800 Plus cardiac application. Also, the OEC 9800 MD can be added to this C-arm to allow for the surgeon’s precise control of the C-arm movement with a joystick-like device. GEMS is the only manufacturer to have integrated a surgical navigation system into its C-arm with the OEC 9800 FluoroTrak. Hales explains that surgical navigation is a “great way to reduce dose and to save surgical time.”

Remanufacturing, Service, and Reselling: The Other Side of C-Arms In addition to manufacturing, the C-arm marketplace includes companies that focus on refurbishing and remanufacturing used C-arms for resale. One such company, Huestis Medical (Tonton, Mass, and Gilbert, Ill) remanufactures GEMS’ OEC 9000, 9400, and 9600 C-arms. Sales Manager Gary Shaw explains that rather than simply refurbishing the units, Huestis Medical thoroughly investigates each system and “breaks them down into the smallest components.” The units are disassembled, cleaned, and restored; parts are replaced, refinished, calibrated, rewired, reassembled, and tested. When the process is complete, “you would never know that [a unit] wasn’t new,” Shaw says.

Huestis Medical’s customers—mainly small and midsize hospitals and pain-management and outpatient centers—are concerned with economics. The smaller facilities might only need an OEC 9000 capability. Shaw explains that by purchasing a remanufactured C-arm, the smaller facilities can then “spend a half or a third of the price of a new unit, and they’ll have all of the functionality they need.” Additionally, Huestis Medical’s remanufacturing quality levels mandate that the specifications meet or exceed the specs of new units. Considering the economics and the warranty levels, Shaw poses the question, “Why wouldn’t customers want to buy [a remanufactured unit]”?

Irrefutably, C-arm equipment performance is extremely important during surgical procedures. A service provider would assist in the proper maintenance of an institution’s C-arm, helping to reduce equipment failures. DMS Health Group (Fargo, ND) is a regional service provider, focusing its business on the service, installation, and reselling of Philips Medical Systems’ products, including C-arms. Servicing ability is an important part of the purchasing decision, explains Nat Geissel, senior VP of the DMS Health Technologies section at DMS Health Group. “Customers will make a decision based on functionality, price, and service,” he says. The company offers 24/7 service coverage, which includes a service call center and more than 50 field service engineers.

Other factors, such as tables designed for specific use with C-arms, need to be taken into account with C-arm utilization. Mount Sinai’s Sundaresan says that the surgical tables used with C-arm procedures are incredibly important to the process. Tables that allow rotations are imperative in imaging the patient at multiple planes. Biodex Medical Systems Inc (Shirley, NY) is one manufacturer of these C-arm tables. Richard Schubert, product sales manager of diagnostic imaging tables at Biodex, explains the importance. “The electronic functions [of the C-arm table] are key” with a control panel, LCD screen, real-time positioning, memory sets, and full-function foot control.

Many models of C-arm tables, such as the Biodex Surgical C-Arm Table-870, 840, and 830, offer multiple positioning control units, permitting doctors and technologists to quickly and safely reposition the table and patient during C-arm procedures. The tables also can be programmed to suit each doctor’s preferred starting position during surgical procedures, based on his height or size. In addition, Biodex recently released a contoured design top, the Surgical C-Arm Table-840, that, according to the company, “combines the advantages of the square design top with those of the contoured top,” enabling closer C-arm access and needed additional space.

Patient Comfort
Undeniably, a few of the most important features of C-arms are image quality, easy maneuverability for proper medical diagnosis, and low dosage for minimum radiation to patients and C-arm users. These features, all constantly advancing technologically, have resulted in a more cost-effective surgical environment as well as greater patient comfort.

In fact, patient comfort is one of the major driving forces behind C-arm use and technical advancement. Patients experience less discomfort during minimally invasive surgical procedures. For example, surgeons can now plan the incision and access points on the spine with the use of a C-arm’s X-ray technology—rather than making a large incision in the spinal area without the use of a C-arm. Sundaresan explains that perhaps the procedure might take longer than former spinal surgeries due to the planning process, but the incision is smaller. The result is less discomfort and pain for the patient.

C-arms also have helped to allow minimally invasive surgery to become more commonplace in the surgical world. Ziehm’s Klawitter says that minimally invasive surgery reduces “pain and trauma” to the patient and lowers costs to the insurance companies. As a result, patients and companies are demanding minimally invasive surgery, which has increased outpatient surgeries as well as outpatient clinics and surgical centers over the past several years.

The bottom line: C-arms can be utilized in various applications in a more cost-effective manner, while increasing patient comfort. And in many cases, using C-arms has helped decrease invasive and painful surgical procedures.

Nici Lewis is a contributing writer for Medical Imaging.