Contact:
Raymond Schulz, Voxel
714-348-3200, [email protected]
Kay Paumier, Communications Plus
510-656-8512, [email protected]
For Immediate Release
Digital Holography System Helps Neurosurgeons Diagnose and Treat Disorders of the Spine
February 11, 1998 ó Rancho Mirage, CA ó Physicians reporting at the annual spine-section meeting of the combined American Association of Neurological Surgeons (AANS) and Congress of Neurological Surgeons (CNS) societies this week will describe how the Digital Holographyô System from VoxelÆ (NASDAQ:VOXL) helps them diagnose and treat disorders of the spine.
The Digital Holography System uses data routinely collected by Computed Tomography (CT) and Magnetic Resonance (MR) scanners to produce true three-dimensional images. A proprietary multiple-exposure process holographically superimposes all the cross-sectional data from the tomographic studies onto a single piece of 14"x17" holographic film. When the film is viewed on a special lightbox, the transparent VoxgramÆ images literally extend out in space, enabling physicians to interact in, around and through the life-size holograms as if they were real specimens of anatomy.
Holograms "Modality of Choice" for Spinal Evaluation Where Hardware is Present
Dr. Wayne J. Olan, Chief of Neuroradiology at George Washington University Medical Center (Washington, D.C.), tested the hypothesis that holograms of hardware would be less prone to artifacts than computer renderings. These artifacts have "been a frequent source of frustration to both clinicians and radiologists as important data in the area of interest cannot be evaluated."
Holograms and 3-D computer renderings were prepared from helical 3-D CT scans of 20 patients with hardware. Dr. Olan found that "hardware-induced beam hardening artifacts are significant on both the opaque ë3-Dà surface renderings and on the conventional axial images." However, the transparent "holographic display virtually eliminated the artifact and clearly displayed the hardware, post-surgical changes and resultant anatomy." This improved display is partially due to the fact that "multiple-exposure holography makes no assumptions about data ëbetween slicesà as renderings must do."
Dr. Olan believes that "holograms appear to be the modality of choice for the display of spinal hardware" because "the lack of artifact allows both the clinician and the radiologist to evaluate the post-op patient without the guesswork required by current display techniques." He concluded that holographic display of helical 3-D CT in the post-op spine patient allows "the clinician and the radiologist to accurately assess the 3-D relationships in those patients with spinal hardware." (Holographic Display of Helical 3D-CT in Patients Status Post Spinal Hardware Eliminates Display Artifacts, Scientific Poster 53, Olan WJ, Schulz RA, Hecht A, Ridel CJ, Levine Z, Sekhar LN)
Surgeons Find Holograms Invaluable for Pediatric C-Spine Abnormalities Dr. Jill V. Hunter, staff neuroradiologist at ChildrenÃs Hospital of Philadelphia, University of Pennsylvania, evaluated whether three-dimensional holograms more completely display congenital anomalies of the cervical spine. Such "variable and highly unpredictable" anomalies "can be extraordinarily hard to interpret because of the difficulties in assessing an unpredictable 3-dimensional problem from a 2D stack of slices."
Dr. Hunter reviewed 19 cases of cranio-cervical anomalies. The patients, who had a median age of 11, were first investigated with CT and/or MRI and then a hologram was produced. Dr. Hunter compared the original CT image data, together with any 2D and 3D renderings, with the true 3D hologram. The comparison "confirmed a faithful reproduction of the information but in a format that was much quicker and easier to read and understand. In at least two cases, the hologram revealed previously unexpected findings that were confirmed at surgery. The surgeons found the holograms invaluable preoperatively, not only for pre-surgical planning" but also to explain the nature of their childÃs problem to the parents. "In addition, because of the portability of the system, it proved feasible and useful to transport the holograms to the OR for interactive use" during the operation.
Dr. Hunter found that "holography produced a faithful representation of both the CT and MR data with the added benefits of being able to view the entire data set of cross-sectional images in 3D on a single sheet of film with different viewing perspectives. Because the holograms are transparent, lifesize and project out in space, true 3D holography has proven invaluable in the understanding of the unexpected relationships of these often abnormally formed bones." (True 3D Digital Holography as a Tool for Displaying Congenital Abnormalities of the Cranio-cervical Junction in a Pediatric Population, Scientific Poster 94, Hunter JV, Domans J, Duhaime AC, Schulz R, Geil G, Drummond D)
Other Studies
In addition to the research cited above, physicians at several other prominent medical institutions throughout the country have studied Digital Holography, including Massachusetts General Hospital-Harvard Medical School (Boston); Stanford University; Irvine Medical Center-University of California at Irvine; and Mallinckrodt Institute of Radiology-Washington University (St. Louis).
The Digital Holography System was awarded FDA clearance in September 1995. In January 1997, Voxel was awarded a US patent covering 13 claims, including five independent claims for the company's method of making multiple-exposure holograms. The company has been notified that an existing reimbursement code for reporting medical procedures was amended effective January 1, 1998, to explicitly reference holographic imaging of CT and MR data. This will provide a method by which clinicians may more accurately report, and seek reimbursement for, use of Digital Holography. Based in Laguna Hills, California, Voxel is a public company founded to develop, manufacture and market volumetric display systems based on multiple-exposure holography.
Voxel and Voxgram are registered trademarks and Digital Holography is a trademark of Voxel.
RSS