CT Scan Protocol DYONICS PLAN. Hip Impingement Planning System. CT Scan Protocol Rev. A

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1 CT Scan Protocol DYONICS PLAN Hip Impingement Planning System CT Scan Protocol Rev. A

2 Protocol Requirements Protocol Requirements The CT exam must adhere to the protocol requirements specified in this document. If it does not fully comply with these requirements, DYONICS PLAN may not be able to load the CT exam or it may compromise the validity of the analysis. If the CT exam is incomplete, DYONICS PLAN may fail to compute some anatomic measurements. Acquisitions Perform only two acquisitions: pelvis and knees. Use the same frame of reference for both acquisitions - i.e., from the same scout view. Required Scout/Topograms For the acquisitions, obtain each of the following scout/ topograms: AP/Coronal Lateral/Sagittal Other Reformatted and 3D Reconstruction Volumes The responsible radiologist should decide whether additional scans from the routine diagnostic protocol should be added to the exam to provide any additional information. Patient Preparation Position the patient so that they are supine, with no unnatural tilt of the pelvis, feet first, legs parallel in neutral position, toes pointing up. Instruct the patient on the importance of holding completely still during the scan. Patient stillness is critical for accurate 3D imaging and modeling. Required Reconstructions Create three or four reconstructions, including the pelvis, the knees, and the right and/or left unilateral hips. The following series must be included in the exam: Reconstruction 1.: Bilateral axial pelvis reconstruction Reconstruction 2.: Bilateral axial knees reconstruction Reconstruction 3.:Unilateral axial right hip reconstruction and/or Reconstruction 4.: Unilateral axial left hip reconstruction You must also include the AP/Coronal and Lateral/Sagittal scout views in the exam. Note: For the unilateral hip reconstruction(s), do not perform a separate acquisition/study for each hip side of interest. Instead, generate the unilateral hip reconstruction(s) from the full pelvis acquisition/study Rev. A DYONICS PLAN CT Scan Protocol

3 Image Acquisitions Image Acquisitions Bilateral Pelvis Start AIIS End Figure 1. ASIS Lesser Trochanter Bilateral pelvis Axial Scanning Range: Start: Midpoint between the anterior inferior iliac spine (AIIS) and anterior superior iliac spine (ASIS) End: 30 mm below lesser trochanter FOV Diameter: 500 mm. Use same X and Y centers for both pelvis and knee scans based on a single coronal scout Collimation Thickness: Minimum slice/row thickness available Pitch: As close to 1.0 as possible Tube Voltage: 120 kv Tube Current Time Product: Small patients: 100 mas Medium patients: 150 mas Large patients: 200 mas Or other standard guidelines, if required by your department or institution.* Bilateral Knees Axial Scanning Range: Start: 40 mm proximal to knee joint line. Figure 2. Start End Bilateral knees Joint Line End: Knee joint line (Scan must cover epicondyles and posterior condyles in their entirety) FOV Diameter: 500 mm. Use same X and Y centers for both pelvis and knee scans based on a single coronal scout Collimation Thickness: Minimum slice/row thickness available Pitch: As close to 1.0 as possible Tube Voltage: 120 kv Tube Current Time Product: Small patients: 100 mas Medium patients: 150 mas Large patients: 200 mas Or other standard guidelines, if required by your department or institution.* *CT scan compatibility with DYONICS PLAN has only been validated for the specified parameters. DYONICS PLAN CT Scan Protocol Rev. A 3

4 s s Reconstruction 1: Bilateral Pelvis Slice Thickness: mm Reconstruction Interval: mm Or Bone Tissue: Siemens: B70, GE: Bone, Toshiba: FC30, Philips: C, or equivalent* Figure 3. Bilateral pelvis reconstruction field of view Reconstruction 2: Bilateral Knees Slice Thickness: mm Reconstruction Interval: mm Or Bone Tissue: Siemens: B70, GE: Bone, Toshiba: FC30, Philips: C, or equivalent* Figure 4. Bilateral knees reconstruction field of view *CT scan compatibility with DYONICS PLAN has only been validated for the specified parameters Rev. A DYONICS PLAN CT Scan Protocol

5 s Reconstruction 3: Unilateral Right Hip Figure 5. Unilateral right hip reconstruction field of view Slice Thickness: Miniminum available (must be less than 1.25 mm) Reconstruction FOV: Less than 250 mm Reconstruction Interval: mm Note: Unilateral reconstructions do not require separate acquisitions. They are reconstructed from the bilateral pelvis acquisition. Note: Either the left or the right reconstruction may not be required. Reconstruction 4: Unilateral Left Hip Figure 6. Unilateral left hip reconstruction field of view Slice Thickness: Miniminum available (must be less than 1.25 mm) Reconstruction FOV: Less than 250 mm Reconstruction Interval: mm Note: Unilateral reconstructions do not require separate acquisitions. They are reconstructed from the bilateral pelvis acquisition. Note: Either the left or the right reconstruction may not be required. *CT scan compatibility with DYONICS PLAN has only been validated for the specified parameters. DYONICS PLAN CT Scan Protocol Rev. A 5

6 DICOM Fields Required DICOM Fields The following table lists the fields that must be present in the DICOM header. If a value is required, it is specified. Otherwise, it is not. Image Type (0008, 0008) Study Date (0008, 0020) Modality (0008, 0060) Patient s Name (0010, 0010) Patient s Birth Date (0010, 0030) Patient s Sex (0010, 0040) Slice Thickness (0018, 0050) Convolution Kernel (0018, 1210) Series Number (0020, 0011) Required Field Acquisition Number (0020, 0012) Image Position (Patient) (0020, 0032) Must contain label AXIAL = CT Must be unique for each series Image Orientation Patient (0020, 0037) = 1.0\0.0\0.0\0.0\1.0\0.0 Photometric Interpretation (0028, 0004) Rows (0028, 0010) = 512 Columns (0028, 0011) = 512 Pixel Spacing (0028, 0030) Bits Allocated (0028, 0100) Bits Stored (0028, 0101) High Bit (0028, 0102) Pixel Representation (0028, 0103) Rescale Intercept (0028, 1052) Rescale Slope (0028, 1053) = MONOCHROME2 Required Value Optional DICOM Fields The following table lists the fields that may be optionally included in the DICOM header. There are no required values. Required Field Accession Number (0008, 0050) Patient Id (0010, 0020) Required Value Endoscopy Smith & Nephew, Inc. 150 Minuteman Road Andover, MA USA Fax U.S. Customer Service 2013 Smith & Nephew, Inc. All rights reserved. 09/ Rev. A