Practitioners are often faced with selecting the correct modality, most often the decision is between MRI and CT Scan. Some of the factors that can determine this are: area of complaint, presenting symptoms, and suspected pathology. We have put together a list to help as a reference in case there is a question to which modality would be best to order.
Area of Complaint | Presenting Symptoms | Suspected Pathology | Imaging Modalities Indicated |
---|---|---|---|
Head | Dizziness | Acoustic neuroma, multiple sclerosis, temporal lobe lesion, tumor, or stroke, sub or epidural hematoma, cyst |
MRI: The most sensitive for suspected pathology listed CT: Less expensive than MRI but not as sensitive |
Head | Seizures | Temporal lobe lesion, tumor, or stroke, multiple sclerosis, cerebrovascular accident, cyst | MRI: The most sensitive for suspected pathology listed CT: Less expensive than MRI but not as sensitive. Exception: CT is more sensitive in acute stage (1st 3 days) post cerebral hemorrhage. |
Head | Localized pain or headaches | Tumor, abscess, arteriovenous malformation, trauma, cyst | MRI: Most Sensitive CT: Less expensive and less sensitive. Exception: CT is more specific for calcified tumors. |
Head | Non-localized headache | Tumor or other space occupying lesion, mastoiditis sinusitis, hydrocephalus, cyst. | MRI: Most Sensitive CT: Less expensive and less sensitive. |
Head | Behavioral changes | Tumor or other space occupying lesion, Cerebrovascular Accident (CVA), cyst or multiple sclerosis. | MRI: The most sensitive for Tumor or Multiple Sclerosis. CT: Less sensitive for hemorrhage in acute stage 2st 3 days post hemorrhage. |
Head | Post Trauma or surgery | Subdural or Epidural Hemmatoma, or other Hemorrhage, Infection, Abscess. | MRI: Most sensitive for Hemorrhage in Subacute Stage (4 to 10 days post trauma) or Chronic Stage (10 days or more post trauma), for infection or abscess. CT: Most sensitive for hemorrhage in Acute Stage 1st 3 days post trauma. . |
Head | Sensory changes | Acoustic Neuroma, Occipital Lobe Lesion, Optic Chiasm or Optic Nerve Lesion, Meningioma, Cyst, Olefactory Nerve Lesion. . |
MRI: Most Sensitive CT: Less expensive and less sensitive. Exception: CT is more specific for calcifying lesions. |
Head | History of Cancer | Metastasis | MRI: Most Sensitive CT: Less sensitive except for calcifying lesions. |
Head | Amenorrhea or Lactation | Prolactinoma, or other Pituitary Tumor | MRI: Most Sensitive CT: Less sensitive due to scatter artifact from Sella Turcica. |
Cervical | Unilateral or Bilateral symptomology of neck or upper extremities. | Arthritic Hypertrophy, Herniated Nucleus Pulposus (HNP), bulging Anulus Fibrosus, Cord Tumor, Syringomylia, Stenosis of Spinal Canal of Foraminal Openings, Non-displaced Fracture, Multiple Sclerosis (MS) | MRI: Most sensitive for various soft tissue structures-discs, canal contents, tumors or MS. CT: More sensitive for bony structures or for non-displaced fracture. |
Cervical | History post trauma or surgery. | HNP, Recurrent HNP versus scar tissue, Ligamentous Tearing, Non-displaced Fracture, Syringomylia, Infection, Recurrent Cord Tumor. | MRI: Most sensitive for Syringomyelia, HNP, or Post Surgery Evaluation. CT: More sensitive for non-displaced fracture. Video Flouroscopy: Most sensitive for joint motion abnormalities post trauma. |
Cervical | Loss of range of motion or excessive motion of individual motor units. | Ligamentous Tearing or Laxity, Muscle Spasm. | MRI: Most sensitive for soft tissue structures and inflammatory reactions. CT: Most sensitive for bone pathology. Video Flouroscopy: Most sensitive for joint motion abnormalities related to ligamentous injury. |
Cervical | History of Cancer or Systemic Disease affecting bone (Pagets, Lupus, etc.) | Metastasis to Spinal Cord, or bony structures, marrow changes secondary to systemic disease, pathological fracture from metastasis. | MRI: The most sensitive for evaluation of Metastasis or marrow changes a known area. CT: Sensitive for bony detail. Nuclear Medicine: Offers whole body coverage for initial localization of metastasis to bone, best for initial screening. |
Thoracic | Unilateral or Bilateral Symptomology of trunk or lower extremities | Arthritic Hypertrophy, HNP, Bulging Anulus, Cord Tumor, Syringomyelia, Stenosis of Canal or Foraminal Openings, Compression Fracture. | MRI: Most sensitive for various soft tissue structures-discs, canal contents, tumors, syringomyelia. CT: More sensitive for bony structures. . |
Thoracic | History Post Trauma or Surgery. | Compression Fracture, Syringmyelia, Recurrent HNP versus Scar Tissue, Recurrent Cord Tumor, Infection. | MRI: Most sensitive for various soft tissue structures. CT: Best for Bony Details. |
Thoracic | History post cancer or Systemic Disease affecting bone (Pagets, Lupus, etc.) | Metastasis to Spinal Cord or Bony Structures, Marrow changes secondary to systemic disease, pathological fracture. | MRI:Most sensitive for evaluating soft tissue structures and marrow. CT: Best for Bony Details. Nuclear Medicine: Offers whole body coverage for initial localization of metastasis disease in bone. |
Lumbar | Unilateral or Bilateral Symptomology of lower back, pelvis, lower extremities, or incontinence. | Arthritic Hypertrophy, HNP, Bulging Anulus, Conus or Cauda Equina Tumor, Stenosis of Canal or foraminal openings, Compression Fracture, Abdominal Aortic Aneurysm, Tethered Cord. | MRI:The most sensitive for soft tissue structures, easily identifies aneurysms. CT: Best for bony details (bulging anulus versus osteopathic growth) also visualizes aneurysms well. |
Lumbar | Compression Fracture, Neural Canal or Foraminal Stenosis, Infection, Recurrent HNP versus scar tissue, recurrent conus or cauda equina tumor. | Compression Fracture, Neural Canal or Foraminal Stenosis, Infection, Recurrent HNP versus scar tissue, recurrent conus or cauda equina tumor. | MRI:The most sensitive for soft tissue evaluation post surgery or trauma. CT: Best for bony detail. |
Lumbar | History of cancer or systemic disease affecting bone (Pagets, Lupus, etc.) | Metastasis to Spinal Cord or Bony Structures, Pathological fracture, marrow changes secondary to systemic disease. | MRI:Most sensitive for evaluating soft tissue structures, best for follow-up evaluation of known mets or marrow abnormalities. CT: Best for bony detail. Nuclear Medicine: Offers whole body coverage, best for initial screening. |
Shoulder | Chronic Dislocation | Glenoid Labrum Tear, Degenerative Joint Disease. | MRI: Most accurately depicts glenoid labrum glenoid fossa. |
Shoulder | Pain and Weakness, Decreased range of motion, history of arthritis or trauma. | Full or partial thickness rotator cuff tear, impingement syndrome, fracture, synovial cysts, neoplasm, effusion, injection. | MRI:Most sensitive for partial thickness tears, same sensitivity as arthrography for full thickness tears, most sensitive for synovial cysts, impingement syndrome, neoplasm, effucion, infection Arthrography: equal sensitivity with MRI for full thickness tears, less sensitive for partial thickness tears. |
Hip | History of cancer or systemic disease affecting bone (Pagets, Lupus, etc.) | Metastatic tumor, occult fracture, marrow changes to secondary systemic disease. | MRI:Highly sensitive to metastatic lesions and marrow changes, can evaluate fractures in multiple planes. CT:More sensitive for bony detail. Nuclear Medicine:Offers whole body coverage best for initial localization of metastatis disease in bone. |
Hip | Unilateral or Bilateral pain, decreased range of motion, history of trauma or surgery. |
Avascular necrosis, tummor, degenerative joint disease, occult fracture. | MRI:The most sensitive imaging modality for detecting in schemic necrosis in bone, only modality that images hyaline cartilage. NOTE: Hip prosthesis patients are safe to scan by MRI degradation of images may or may not occur depending on content of prosthesis. CT:Good bony detail, sensitive for occult fractures. |
Wrist, Elbow, Ankle, and Foot | Pain, decreased range of motion, history of trauma or prior surgery, history of arthritis. | Vascular necrosis, intra-articular loose bodies, transchondral fracture, cyst formation, tendon or ligament tearing, soft tissue or bony tumor, fracture non-unions. | MRI:The most sensitive for soft tissue evaluation and chronic fractures, multiplanar evaluation advantages. XRAY: Best for bony detail and morphology. .. |
Chest: Lungs and Heart | History of cancer or Hodgkin’s disease.. | Metastasis, Lymphatic Involvement. | MRI:Less sensitive than CT, but good for followup if CT is equivocal, images substernal lymphadenopathy well – no scatter artifact. CT: Equivalent to or more sensitive than MRI, less affected by peristaltic, respiratory and pulsatile motion, best for initial screen. Ultrasound: Offers high resolution imaging of lesions, good initial screen if small lesions are suspected. |
Abdomen: Liver, Spleen, Pancreas, and Kidneys | History of cancer, loss of function, chronic or acute, localized or non-localized abdominal pain. | Primary or Metastatic, Tumor Involvement, benign cyst, hemochromatosis, infection. | MRI: Equivalent to or less sensitive than CT, good for follow-up when CT is equivocal, best for hemochromatosis. CT: Equivalent to or more sensitive than MRI, less affected by peristaltic, respiratory pulsatile motion, best for initial screen. Ultrasound: Offers very high resolution imaging of lesions, good initial screen if small lesions are suspected. |
Pelvis: Bladder, Uterus, Ovaries, Prostate | History of benign masses or cancer, chronic or acute localized or non-localized pelvic pain. | Primary or metastatic, tumor involvement, benign tumor or cyst, infection. | MRI: Best at evaluating wall invasion by Tumor growth best for follow-up after tumor sites have been localized with CT. CT: Good for initial screening and localization of gross tumors.. Ultrasound: Best for initial screening of pelvic lesions, real time imaging offers best structure identification, very high resolution capabilities. |
Main Office:
PALM HARBOR MRI
32615 US Hwy 19 North
Palm Harbor, FL 34684
Phone: 727.787.6900
Fax: 727.216.4789