Page 138 - Registrar Orientation Manual 2016

Reference:
1257
Effective date:
7 July 2015
Expiry date:
6 July 2018
Page:
21 of 35
Title:
Imaging Guidelines
Type:
Clinical Guideline
Version:
02
Authorising initials:
Repeated imaging in a patient with epilepsy is not indicated unless there are features suggesting a new cause of seizures or a complication is suspected, for example significant new neurological signs, fever, or a prolonged reduction in the level of consciousness. See SMO advice.
Clinical urgency: We recommend an urgent CT scan 24/7 if:
• persistent altered mental status (with or without intoxication)
• a structural brain lesion is suspected with new onset partial seizures or focal deficit
• fever suggestive of CNS infection (LP then also needs to be performed)
• recent significant head trauma or anticoagulation
• history of malignancy and suspicion of brain metastases
The ‘Choosing Wisely’ recommendations include:
Neuroimaging (CT, MRI) is not necessary in a child with simple febrile seizure.
Fractures (See Trauma)
If plain radiology fails to demonstrate a clinically suspected fracture options include repeating imaging with plain films after an interval, bone scanning, CT and MRI. The best modality will depend on the site of the suspected fracture and the options for treatment. It is not always necessary to demonstrate a fracture when management will not change for example rib or stable pelvic fractures. Seek appropriate specialist advice before requesting further imaging.
The ‘Choosing Wisely’ recommendations include:
Don’t request imaging for acute ankle trauma unless indicated by the Ottawa Ankle Rules (localised bone tenderness or inability to weight-bear as defined in the Rules).
Gastrointestinal Conditions (Other)
MRI enterography has replaced Barium imaging in the assessment of selected patients with Crohn’s.
Gynaecological Conditions (see also Malignancy)
The main first line imaging modality is ultrasound (US).
If US is abnormal, or histology shows a malignancy, further imaging may be required.
To stage malignancy, CT of the chest, abdomen and pelvis is usually the first line investigation.
To stage a known endometrial cancer for myometrial invasion or cervical cancer for parametrial invasion, MRI is usually requested as well.
MRI may also be used in selected cases in the investigation of suspected malignancy of the cervix, endometrium, ovaries, uterine abnormalities such as fibroids if a sarcoma is suspected.
A MRI may also be requested for the following non-malignant indications:
• investigation of known or suspected Mullerian tract abnormalities
• investigation of abnormal placentation ? placenta percreta ? trophoblastic disease
• investigation of suspected fistula of genito-urinary +/- GI tract
• upon recommendation from Radiology (usually for the above) or another speciality.
MRI is only indicated in the investigation of endometriosis (for staging/bowel/bladder involvement), if patients are previously known to have endometriosis, or have large endometriomas on USS +/- renal
MRI is not a screening test for endometriosis and should not be performed if USS is normal.
Clinical urgency: Usually within 1-2 weeks desirable, to allow treatment decisions to be made.
The ‘Choosing Wisely’ recommendations include:
Avoid routine imaging for cancer surveillance in women with gynaecologic cancer, specifically ovarian, endometrial, cervical, vulvar and vaginal cancer.
Don’t recommend follow-up imaging for clinically inconsequential adnexal cysts.