MRI Lumbar Spine Disc Herniation

One of the most often scanned areas of the body is the lumbar spine.  An MRI of the lumbar spine is most often done to determine if a patient has a herniated disc.  Patients will usually present with low back pain with associated buttock or lower extremity pain.  Don't be alarmed if a patient has a lumbar disc but no apparent low back pain though.  Many patients do not complain of low back pain.  It just depends on which nerves are being compressed.  Routine MRI sequences are T1 and T2 sagitals and T1 and T2 axials.  STIR sagitals will be performed if the patient has had a distinct recent injury.  Here is a website with images and discussion about this:  http://www.mayfieldclinic.com/PE-HLDisc.htm

MRI Thoracic Spine

MRI of the thoracic spine is very useful to depict compression fractures.  These fractures can and do happen to individuals more often when they have low calcium levels in their bones.  Many times this will be the first sign that a person needs to be tested for osteoporosis.  Sometimes these fractures can be treated by a procedure called vertebroplasties.  This is were a substance like cement is injected into the vertebral body to help maintain the structure.    MRI is usually done to find these fractures.  You must do a STIR sequence with a routine study.  This will show if the fracture is acute.  A good website with further explanations and images about this is:  http://www.aafp.org/afp/2004/0101/p111.html

MRI Cervical Spine Metastatic Disease

Many cancers will become metastatic and bones are a common place for the cancer to metastasize to.  Not all cancers due this, but many including lung and breast will find their way to the bone.  The most common sites for metastasis is the pelvis or spine.  When a cancer goes to the spine there is a possibility that it can cause a cord compression which is considered an emergency.  MRI's allow quick diagnosis of this.  There are not many emergency MRI's, but cord compressions top the list.  If a patient has a cord compression it can completely block the nerves and cause a patient to loss control of their body in many ways including bowel and bladder incontinence, inability to walk and loss of use of extremities.  These patients will usually present with uncontrolled or intractable pain in the spine.  http://www.merck.com/mmhe/sec06/ch093/ch093c.html is an educational website on cord compressions of all different types.  Usual imaging of cord compression with MRI include T1, T2 fatsats and sometimes STIR sagitals and T1 and T2 fatsat axials.  Post contrast imaging is also usually performed with repeating the T1 images.  The following are images of a slight cord compression laterally with bony metastatic disease.

 T1 SAGITAL

 T1 STIR SAGITAL

 T1 AXIAL

 T1 SAGITAL POST CONTRAST

T1 AXIAL POST CONTRAST

MRI Trachea Tumor

Tumors of the trachea sometimes hard to diagnose as many patients don't realize they have some pathological reason for their problems so they do not immediately go to the doctor.  Sometimes tumors of the trachea prevent people from swallowing or breathing easily as the tumor may be blocking this function.  Most tumors of the trachea are malignant, but fortunately these tumors occur very infrequently.  Smoking is a risk factor for these tumors.  Here is a website with valuable information on these types of tumors:  http://emedicine.medscape.com/article/425904-overview

MRI can be used for diagnosis of these tumors.  Ultimately a biopsy would need to be performed, but with excellent soft tissue imaging this is sometimes the first step in diagnosis.  A basic protocol of T1 and T2 imaging with post contrast T1 imaging is pretty much all one needs to image this area.  Usual neck imaging contains axial and coronal imaging, but since this structure is midline, sagital imaging should also be performed.  Attached are some images of this:

 T1 SAG

 T1 COR

 T1 AXIAL

 T1 SAG POST CONTRAST

T1 AXIAL POST CONTRAST

Aneurysm COW

MRA's of the brain are done for cerebral aneurysms.Some patients with acute ruptures present with a stabbing headache out of nowhere.  Others present with history of headaches in particular areas, eye pain, pulsing or family history of aneurysm.  Sometimes larger aneurysms can be harder to see on MR due to the fact of getting lack of flow in the bulb of the aneurysm.  If flow in the aneurysm is not flowing frequent enough it will not show up on the MRA as well due to the nature of the imaging.  Since brain MRA's are usually done non contrast, this can make a diagnosis difficult.  If a patient has an aneurysm they will usually require surgery and have a coil or clip placed to stop the progression and the possibility of rupture. The following website has great information regarding the whole aspect of cerebral aneurysms:  http://www.ninds.nih.gov/disorders/cerebral_aneurysm/cerebral_aneurysm.htm

The following images are of a middle cerebral brain aneurysm:

Cavernous Sinus Fistula

A cavernous sinus fistula happens when the internal and external carotid arteries and the cavernous sinus gets their "communication" mixed up.  These patients usually see an eye doctor first with eye pain or proptosis.  Sometimes these happen spontaneously but more often by trauma.  A usual protocol for our facility would be images of the entire brain,but also including:
Pre-contrast of orbits

• T1 fatsat coronal      
•  T1 Axial 
•  thin slice Cor T2 

Post contrast of orbits:

• Fat sat Axial T1
• Fat sat Cor T1
• Fat sat Sagital Oblique (angled with optic nerve) of both orbits

The following web site has some basic information:  http://emedicine.medscape.com/article/1217766-overview

The following images are from a patient with a cavernous sinus fistula right side seen posterior orbit cavity.  You can also see the proptosis in the right eye compared to the left.

T2 Axial

T2 coronal

T1 axial

T1 axial post contrast fatsat

T1 Sagital oblique post contrast fatsat



Pituitary Microadenomas MRI

Micoradenomas, on MRI imaging, can be seen best by using a pre and post contrast gadolinium enhanced study detailed to the pituitary gland.  Dynamic imaging of the pituitary gland can increase the sensitivity of seeing the microadenoma in some instances.  This article shows some studies related to the sensitivity and specificity of the dynamic imaging.  http://www.endocrinology.org/education/resource/summerschool/2004/ss04/ss04_byr.htm
Many of these patients will present with some kind of metabolic or hormonal imbalance, including, but not limited to:  absence of menstruation, lactating breast, breast development in males, any many other hormone regulated problems.  I have included some imaging of a patient with a microadenoma on the right side of the patients pituitary gland, displacing the infundibulum slightly to the patients left.  I have also included a dynamic image showing the actual absence of contrast enhancement as the pituitary gland enhances.

T1 Coronal pre contrast

T1 Coronal post contrast

T1 Sagital pre contrast

T1 Sagital post contrast

Dynamic Coronal about 30 seconds post injection