RANZCR MRI CLINICAL IMAGE REVIEW PROGRAM : SELF-AUDIT

Transcription

1 RANZCR MRI CLINICAL IMAGE REVIEW PROGRAM : SELF-AUDIT This program is available to sites with machines that have met the MRI clinical image review requirements by peer review at least once previously. Sites that participated in Clinical Image review in Stage 1 but not in Stage 2 will be required to undergo peer review once more before becoming eligible for self-review.each MRI site undertaking clinical image review by self-audit is required to perform the review on each magnet/machine Annually, commencing in More frequent review is encouraged. For each magnet, images from the following examinations and sequences are to be reviewed : 1) Brain scan for suspected multiple sclerosis must include an axial long TR, long TE sequence, and a sagittal or coronal FLAIR or long TR, short TE sequence ( Brain A ) 2) Cerebral MR angiogram for the assessment of stroke ( Brain B ) 3) Cervical spine examination for suspected radiculopathy - thin-section (section thickness 4 mm or less) axial images. 4) Lumbar spine examination for sciatica sagittal and axial long TR, long TE images 5) Knee examination for suspected internal derangement one sagittal and one coronal sequence, at least one to show fluid with hyperintense signal Sites at which most examinations are of the paediatric age group may elect to review images from the following alternative set of examinations and sequences 1) Knee for internal derangement or tumour staging 2) Brain A, screening examination for investigation of epilepsy 3) Brain B, Evaluation of Circle of Willis for stroke 4) Whole spine examination for suspected dysraphism More detailed parameters for each of the imaging sequences nominated above are given in the appended table 1 (table 1p for paediatric sites). Examinations for review should be chosen at random from a pre-defined random time period (typically one week), nominated in advance by the site.perhaps a week Actual parameters used should be recorded. Each examination should be reviewed against the criteria set out in the Instructions for Reviewers document (table 2) by two reporting MR radiologists (not necessarily supervising MRI radiologists), with results recorded in writing (eg on copies of the standard assessors forms) The main outcome measure is whether the images are adequate for clinical diagnosis failure to meet one single detailed criterion does not mean the study is. Images failing to meet criteria, especially those where the failure renders the images nondiagnostic, should be reviewed for potential causes, and subsequent similar examinations reviewed in the same manner, after corrective action has been taken. Images (either on film or electronic) of each examination, and written records of the parameters and the results of the image review, should be retained by the practice, and be available for review by the accreditation assessors In addition, during the assessment, the service schedule and records may be reviewed.

2 TABLE 1 Imaging sequences for Clinical Image Review For each anatomical region, all images must come from the same patient examination. Please leave imaging parameters on the films. Where possible, only perform review on normal films. Images should be acquired within a normal time frame as extended acquisition periods will not be acceptable. For all images, the field of view employed should be the standard size required to include the whole of the specified anatomical region. The minimum matrix size required is stated for each sequence (phase encoding direction first). A maximum slice thickness of 4 mm is specified for the axial cervical spine images. Slice thickness and gap should be appropriate to the stated indication, but are not more narrowly prescribed for the other sequences. Images may be reviewed and archived on film or electronically. Knee: Routine examination for internal derangement or meniscal injury 1, 2 Two sequences, one coronal and one sagittal. One sequence with bright fluid. MINIMUM MATRIX SIZE for each sequence: 192 x 256 Brain A: Routine examination for suspected multiple sclerosis 1 long TR, long TE MINIMUM MATRIX SIZE: 256 x or coronal fluid-attenuated inversion recovery (FLAIR) OR or coronal long TR, short TE MINIMUM MATRIX SIZE: 256 x 256 Brain B: Evaluation of Circle of Willis for stroke 1 MRA of Circle of Willis NB: no need to include neck or most of posterior fossa. Please submit BOTH source ( partition ) images and post-processed maximum intensity projection (MIP) images. MINIMUM MATRIX SIZE: 128 x 256 Cervical Spine: Routine examination for suspected radiculopathy 1 Thin-section axial images from C4 to T1, dark or bright CSF. Maximum section thickness: 4 mm (sites may prefer 3 mm) MINIMUM MATRIX SIZE: 128 x 256 Lumbar Spine: Routine examination for sciatica 1 long TR, long TE 2 long TR, long TE, at least from L3 to S1

3 TABLE 1P Imaging sequences for paediatric Clinical Image Review For each anatomical region, all images must come from the same patient examination. Please leave imaging parameters on the films. Where possible, only perform review on normal films. Images should be acquired within a normal time frame as extended acquisition periods will not be acceptable. For all images, the field of view employed should be the standard size required to include the whole of the specified anatomical region. The minimum matrix size required is stated for each sequence (phase encoding direction first). The slice thickness and gap employed should be appropriate to the region and indication specified. Images may be reviewed and archived on film or electronically. Knee: Examination for derangement or tumour staging 1, 2 Two sequences, one coronal and one sagittal. One sequence with bright fluid. MINIMUM MATRIX SIZE for each sequence: 192 x 256 Brain A: Screening examination for epilepsy 1 long TR, long TE 2 or Coronal fluid-attenuated inversion recovery (FLAIR) MINIMUM MATRIX SIZE: 128 x 256 OR or Coronal long TR, short TE Brain B: Evaluation of Circle of Willis for stroke 1 MRA of Circle of Willis NB: no need to include neck or most of posterior fossa. Please submit BOTH source ( partition ) images and post-processed maximum intensity projection (MIP) images. MINIMUM MATRIX SIZE: 128 x 256 Spine: Whole spine examination for suspected dysraphism 1 long TR, long TE 2 long TR, long TE, at least from L3 to S1 3 short TR, short TE

4 TABLE 2 NOTES FOR MRI CLINICAL IMAGE REVIEWERS As a result of the previous peer review program and subsequent discussions by reviewers, the following principles have been developed to assist you when reviewing the images. Marking the Checklists Please mark any item which you believe to be SUB-OPTIMAL. The purpose of marking boxes is to prompt attempts to improve the quality of the site s images. Making Comments Feel free to make suggestions or comments to assist facilities to improve their images. Adequacy Pass / Fail Only images which are not adequate for diagnosis should be failed. eg, graininess can be unattractive but images should only be failed if the image is too grainy for diagnosis. It may be useful to bear in mind the following principle: In your practice, would you consider these images adequate for the stated clinical indication, or would you seek additional, better-quality, images? Some suggested QUALITATIVE PASS/FAIL CRITERIA are: Clinically relevant (sometimes) surrogates for spatial resolution measurements, eg: Knee Brain MRA Cervical spine Lumbar spine bony trabeculae not seen on T1 WI Normal ACL fibres not seen in coronal images cranial nerves 2, 7,8 not visible on T2WI pituitary stalk not visible on T2WI ophthalmic arteries not visible First-order branches of MCA not visible/discontinuous no cervical rootlets visible intradurally (full length of rootlet not expected) paired dorsal and ventral rootlets of lower lumbar roots not resolved near lateral recesses

5 Knee - Routine examination for internal derangement or meniscal injury Check: Are both sequences from the same patient? Images do not include both sagittal and coronal images Neither sequence shows fluid as bright Poor definition of surrounding soft tissues Coronal Poor definition of surrounding soft tissues Does not visualise entire knee from above patella to tibial metaphysis Coronal Does not visualise entire knee from femoral condyles to below tibial tuberosity matrix size specifications assume square field of view. acceptable if a rectangular field of view is used, provided the FOV is appropriate to the region examined. (min 192 x 256) FOV inappropriate Trabeculae and cortex are not sharply defined (ignore if fatsuppressed sequence) Menisci and cruciate ligaments are not well-defined Coronal (min 192 x 256) FOV inappropriate Trabeculae and cortex are not sharply defined (ignore if fatsuppressed sequence) Menisci, cruciate ligaments and collateral ligaments are not welldefined Filming Technique Density is (film is generally too dark/bright) Please indicate any excessive artefacts below:

6 Brain A - Routine examination for multiple sclerosis Check: Are both sequences from the same patient? CSF not hyperintense relative to brain Poor grey-white matter contrast or Coronal FLAIR or Long TR, Short TE Excessive CSF flow artefact Poor brain/csf discrimination CSF hyperintense to white matter Poor grey-white matter contrast Does not cover from lateral to temporal horn to lateral to contralateral temporal horn Does not cover from scalp at vertex to C2 level Does not cover from vertex of hemispheres to foramen magnum Coronal Does not cover from crista galli to torcula (min matrix 192 x 256 [FLAIR] or 256 x 256)* (min matrix 256 x 256)* Cranial nerves 2, 5, 7 and 8 and pituitary stalk not visible in cisterns Filming Technique (not applicable if electronic image review) Density is (film generally too bright/dark) Please indicate any excessive artefacts below: * matrix size specifications assume square field of view. acceptable if a rectangular field of view is used, provided the FOV is appropriate to the region examined.

7 Cervical Spine - Routine examination for suspected radiculopathy Filming Technique (not applicable if electronic image review) Density is (film generally too dark/bright) Poor contrast between cord and CSF Poor contrast between disk and CSF Does not cover from C4 to T1 (min matrix 128 x 256)* (max 4 mm) No cervical rootlets visible intradurally Please indicate any excessive artefacts below: * matrix size specifications assume square field of view. acceptable if a rectangular field of view is used, provided the FOV is appropriate to the region examined.

8 Lumbar Spine - Routine examination for sciatica Check: Are both sequences from the same patient? CSF not hyperintense to the cord/nerve roots so that cord/nerve roots are not clearly defined Inhomogeneous signal intensity in conus Poor contrast between disk and CSF Nerve roots are not clearly defined Poor contrast between disk and CSF Excessive brightness of fat (obscures tissue planes) Does not cover from T12-S2 inclusive and laterally through neural foramina Does not cover from at least L3 to S1 inclusive (min matrix 192 x 256)* (min matrix 192 x 256)* Dorsal and ventral rootlets not resolved near lateral recesses Filming Technique (not applicable if electronic image review) Density is (film generally too dark/bright) Please indicate any excessive artefacts below: * matrix size specifications assume square field of view. acceptable if a rectangular field of view is used, provided the FOV is appropriate to the region examined.

9 Brain B Evaluation of Circle of Willis for stroke Check: Have both source and MIP images been submitted: Filming Technique (not applicable if electronic image review) Are both image sets from the same patient? MRA MRA Does not cover from petrous carotid to genu MRA (min matrix 128 x 256 in plane)* matrix size relative to FOV (phase) Ophthalmic arteries and/or M1 branches are not visualised in either image set, or are discontinuous Density is (film generally too dark/bright) Please indicate any excessive artefacts below: Dephasing signal loss Slab boundary effect/ venetian blinding * matrix size specifications assume square field of view. acceptable if a rectangular field of view is used, provided the FOV is appropriate to the region examined. adapted from ACR materials