Volume 3 Number 3 Fall 97

Master List
Volume 3 Number 3
Fall 1997

IN THIS ISSUE

Technologic Improvements Expand MRI Services at TKC

FAQs

Magnetic Resonance Imaging

Radiology Department
Update

TECHNOLOGIC IMPROVEMENTS EXPAND MRI SERVICES AT TKC

Major upgrades at the Magnetic Resonance Imaging (MRI) facility in The Kirklin Clinic enhance the quality, versatility, and efficiency of MRI services.
The first phase, completed in late 1996, involved installing the Impact Expert package on the facility's Siemens 1.0 Tesla magnet. The second phase, to be completed in July, 1997, rebuilds the older 1.5 T unit as a GE Signa Horizon LX machine. During the latter upgrade, a mobile scanner has been added to maintain services.
The upgrades result in faster studies with higher quality images. Faster imaging occurs primarily through two mechanisms. First, new data processing features enable formation of images with smaller sets of data. Second, faster manipulation of magnetic fields allows acquisition of more data in a given amount of time. Improvements in scan prescription and image filming further decrease the time needed for each patient. Many new capabilities of the facility pertain to abdominal imaging. Abdominal MRI has lagged behind MRI of the central nervous system and musculoskeletal system because of long exam times, motion artifacts, and poor image quality. Traditional abdominal MRI required sequences up to 20 minutes long, with total examination times over one hour. TKC's upgraded scanners can obtain high quality images of entire abdominal organs during a single breathhold. Sequences are as short as twenty seconds, and total exam time is a fraction of what it had been previously. Improved signal comes from a new vest-like phased array coil specifically designed for imaging the torso.

Sagittal T2 weighted Pelvic MRI shows presacral mass.

Breathhold T1 weighted post gadolinium MRI shows a cystic enhancing renal mass.

T2 breathhold images through the liver and right kidney utilizing Feridex.

7 sescond breathhold Magnetic Resonance Choloangio-Pancreatography (MRCP).

Abdominal applications improved with this new technology include imaging of the liver, kidneys, biliary tree, pancreas, and abdominal vasculature. MRI is a high quality alternative to CT in many patients with hepatic or renal disease, and MR is superior to CT when the patient cannot receive iodinated contrast. Magnetic Resonance Cholangio-Pancreatography (MRCP) is a noninvasive alternative to endoscopy for evaluating the biliary and pancreatic ductal system. If MRCP shows that a patient does not have a condition warranting endoscopic therapy, then the patient can be spared endoscopy (with its inherent risks).
MRI can also provide valuable information about patients with pancreatic neoplasms or with complications of pancreatitis. Faster imaging with decreased motion artifact allows higher quality studies of abdominal vessels, such as renal arteries.
Neuroradiology still accounts for the majority of MRI studies, and will continue to do so. In fact, the high demand for studies of the central nervous system is the driving force behind the upgrades. The new equipment will eliminate long waits to get exams, improving responsiveness to the requests of referring physicians. Patients will appreciate shorter waits and faster examinations. The same can be said for patients with musculoskeletal disorders. TKC can now offer rapid, high quality service which can effectively operate in Birmingham's highly competitive musculoskeletal MR arena. Both technologists and radiologists at TKC's MRI center are excited about this new opportunity to provide better services for their patients and referring physicians.

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FAQs - Frequently Asked Questions

Q: What types of MR contrast material are available for use?

There are two types of intravenous contrast approved by the FDA for use in Magnetic Resonance Imaging. The most commonly utilized contrast agents contain gadolinium and have distribution properties similar to iodinated IV contrast agents typically used for CT scans, IVPs and arteriography. Gadolinium helps to enhance contrast differences between normal tissue and tumors or inflammatory processes in the abdomen and pelvis. However, there is no iodine in gadolinium containing contrast agents, and thus, gadolinium enhanced MRI of the kidneys, liver, pancreas, or gynecologic structures may be substituted for CT scanning in patients with iodinated contrast allergies. Gadolinium also improves the vascular signal in 3D MR angiography, a newer noninvasive way to evaluate the aorta and peripheral vessels. Another MRI contrast agent which contains super paramagnetic iron oxides (SPIOs) has recently been approved by the FDA specifically for use in the liver. This compound is taken up by the reticuloendothelial system and makes normal hepatic tissue dark on T2 sequences, allowing liver metastases or primary tumors to stand out brightly against the dark background. Other types of hepatic and blood pool specific contrast agents are undergoing clinical trials, but are not presently available for use.

Q: What is the role of MR in evaluating recurrent cervical CA?

Because of innate tissue contrast, or signal differences in the endometrial, myometrial, and parametrial structures brought out by T2 sequences, MRI is much more accurate than either CT or physical exam combined with IVP for staging cervical carcinoma. Recent studies have shown that when MRI is the first study used to evaluate patients, money is saved and more invasive diagnostic procedures are avoided. For evaluation of patients with suspected recurrent carcinoma of the cervix, MRI with gadolinium enhancement is useful for differentiating post radiation fibrosis (which often appears mass-like) from recurrent neoplastic tissue.

Q: What is the role of MR in evaluating liver tumors?

Again because of innate contrast differences between normal hepatic parenchyma and most neoplastic tissue, tumor detection rates with MRI are similar to those with contrast enhanced CT. Adding gadolinium contrast enhancement to the MRI protocols often enables better characterization of the lesion or lesions. The multiplanar capability of MRI may also better delineate the relationship of the tumor to adjacent structures such as hepatic vessels or the diaphragm, and is helpful for surgical planning. Early trials have shown SPIO agents to be as accurate as CT portography in the detection of hepatic metastases; this type of examination may eventually replace standard contrast enhanced CT in screening for metastases, or be required prior to surgical therapy for hepatic metastases. Some centers routinely use MRI for evaluation of the liver in cirrhotic patients. At UAB, we utilize MRI to solve questions left unanswered by CT in these patients, but we do preferentially perform MRI of the liver in hemochromatosis patients as well as in patients who cannot receive the iodinated contrast which is necessary to evaluate the liver with CT.

Q: What is the role of MR in evaluating pancreatic disease?

Gadolinium enhanced MRI has been used to evaluate patients with pancreatic carcinoma prior to surgical resection. MRI readily identifies lymph node or liver metastases similar to CT scanning, but MR angiography sequences also provide more detailed information regarding the vessels surrounding the pancreas in determining local resectability. At UAB, we have studied the use of MRI to evaluate the pancreas in patients with severe, necrotizing pancreatitis to establish the feasibility of nonsurgical drainage. In the near future we plan to study the accuracy of gadolinium enhanced MRI compared to the standard, contrast enhanced CT in establishing the presence of pancreatic necrosis, and subsequently a hospitalization cost effective comparison of the two modalities will also be undertaken.

Q: What advantage can MR offer in evaluating biliary disease?

Magnetic resonance cholangiopancreatography, or MRCP, has developed over the past two years into an effective tool for evaluating the bile and pancreatic ducts. In some academic centers, MRCP has substantially displaced diagnostic ERCP. Studies have shown that MRCP is equivalent to diagnostic ERCP in detecting the level as well as the etiology of bile duct obstruction. MRCP is equivalent to ERCP and better than ultrasound for the detection of common bile duct stones. There are several methods used to obtain MRCP images, which look very similar to spot radiographs obtained during standard ERCP. Because the MRCP images are acquired during breath holds ranging from 7 seconds to 35 seconds on the MRI scanners at The Kirklin Clinic and University Hospital, this exam takes only 10 minutes to perform. However, unlike ERCP, no sedation of the patient is necessary and the procedure is completely noninvasive.

Q: How can MRI be used to evaluate the pregnant patient?

Because no ionizing radiation is used for MRI, it is the cross sectional imaging modality of choice in pregnant women. MRI is often used to evaluate abdominal or pelvic masses in pregnant patients, particularly during the second trimester when surgical options are contemplated. Certain MRI protocol modifications are made to lessen the energy deposited within the patient during the MRI scan, and we generally refrain from using gadolinium enhancement as there has been no testing of its affects on the human fetus. MRI is often used specifically to evaluate complications of pregnancy such as rapidly enlarging leiomyoma or adnexal masses, uterine dehiscence, and congenital uterine malformations.

Q: How do I schedule an outpatient for body or musculoskeletal MRI?

The telephone number for MRI scheduling at TKC is 731-9380. When calling this number, be prepared to hold for possible several minutes while scheduling personnel answer other calls.

Q: What if I need to schedule an patient who needs anesthesia, extensive pain control, etc requiring more than PO medications?

These patients will be scanned at the West Pavilion with the assistance of the Anesthesiology Department. Call 934-2796 to discuss the patient with the MRI technologists. A patient information form will need to be completed and Faxed to MRI. The case will then be scheduled with Anesthesiology. You will need to call one Day Surgery (934-2627) to schedule admission of your patient in order to obtain monitoring after the procedure.

Q: What if I need to schedule a patient for a body or musculoskeletal MRI to be done more quickly that routine scheduling will allow?

Please call the body or musculoskeletal radiologist scheduled to cover MRI on that day and discuss the case. We will try to accommodate reasonable requests. If you have difficulty contacting the scheduled MRI radiologist, please page any of the Body MRI faculty
Therese Weber, Phil Kenney, Jay Listinsky, Kevin Smith, Desiree Morgan, or Brian Jones.

Q: How do I schedule an inpatient for body or musculoskeletal MRI?

Call 934-2796 and discuss the patient with the technologists prior to generating a computer request. Factors to keep in mind when scheduling an inpatient for MRI include that:

1) the patient will be capable of holding still for the examination. Motion artifact degrades the images.

2) the patient weighs less than 300 lb and will fit within the bore of the scanner

3) the patient is able to lie flat and breath evenly. Panting respiration again will cause extensive motion artifact which will degrade the images

4) the patient does not have any contraindications for MRI

There are several conditions that will automatically exclude patients from having a MRI exam. These would include:
1. cardiac pacemaker
2. pacer wires from a prior pacemaker
3. cranial aneurysm clips
4. implanted infusion pumps, TENS units, etc.

Other circumstances that may or may not exclude a patient from having a MRI exam should be addressed prior to scheduling the MRI appointment and include:
1. history of metal in the eyes. This should be excluded by appropriate radiographs.
2. cochlear implants: most are unsafe to scan
3. penile implants: some are unsafe to scan
4. artificial heart valves: while most are safe to scan, there are a couple which are not.
5. insurance precertification: some insurance companies require that MRI exams be approved prior to being done.

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Superficial Femoral Vein Name Change

At a recent American College of Radiology Standards Meeting, it was decided to return to the "old name" for the superficial femoral vein - the femoral vein (FV). This is in response to the recent JAMA article which stated that there was significant confusion on the part of physicians with respect to the superficial or deep nature of the superficial femoral vein. This is a critical issue, as if a clot is in the deep venous system, anticoagulation is usually indicated; if it is in the superficial veins, then anticoagulation usually is not performed.

According to experts in the field, anatomists have called the "superficial femoral vein" the "femoral vein" for years. The common usage of superficial femoral vein has been a recent phenomena.

Thus, at the American College of Radiology Standards Meeting, it was agreed that the superficial femoral vein would from now on be called the femoral vein. The deep femoral vein or profunda femoral vein will be called the profunda femoral vein. Note that both the femoral vein and profunda femoral vein are deep veins.

On the PIN system, under Radiology Ultrasound, order lower extremity or upper extremity veins. When you are ordering a DVT examination, please note any focal areas of tenderness or swelling in either the upper or lower extremity. After a thorough evaluation of the deep venous system (common femoral vein, femoral vein, and popliteal veins in their entirety), we examine any focal areas of tenderness for superficial thrombosed veins that may be causing the patient's symptoms.

This is part of our continuing efforts to improve the clarity and usefulness of our ultrasound reports.

New 24/7 service from Radiology Film Library

"Effective immediately, there is now 24 hour, seven day per week service from the UABH 6th floor Radiology Film Library. Rather than requesting that films be located by technologists on duty, a new night shift of film library personnel has been established. They can be reached by the usual number: 4-5135 or by walk-up service. We hope that you will find that this is convenient and worthwhile. Please let us know if you have comments.

Additionally, a major renovation project involving the main Radiology Film Library will begin in September, 1997. We will be temporarily moving the Film Library for about two months while the renovation is being performed. Please follow the signs to our temporary facility on the sixth floor. Thank you for tolerating this inconvenience."

We need your help! The Department of Radiology is developing a pamphlet for outpatients to provide general information on procedure locations, directions, and waiting room information. These pamphlets will be distributed to referring clinics soon. As you refer patients to the hospital for radiological procedures, please give them a Radiology pamphlet and a "Hospital Walkways" map. The maps are available now at no charge from Central Supply.

This information will enable the patients to come to the correct area and will clarify where families should wait. If questions arise, call Carol Lord at 934-0160.

Visions is published quarterly by the University of Alabama Hospital, Department of Radiology. Professor and Chairman: Robert J. Stanley, MD, Vice-Chairman for Operations and Academic Affairs: Robert E. Koehler, MD, Vice Chairman for Planning and Administration: Lincoln L. Berland, MD, Director of Outpatient Services: Peter Dempsey, MD. Visions Staff - Managing Editor: Pat Moore. Editors/Writers: Lincoln L. Berland, MD, Rachel Oser, MD, Robert Lopez, MD. Web Master: J. Kevin Smith, MD, PhD. Creative Services Staff - Editor: Jo Lynn Orr. Art Director: Jason Bickell. Please direct questions, comments, and suggestions as follows: Attention Angie French or Lincoln L. Berland, MD. Fax: 975-7213 Address: NHB 623B E-Mail lberland@uabmc.edu
UAB Radiology Home Page: www.rad.uab.edu

Q: What types of MR contrast material are available for use?	There are two types of intravenous contrast approved by the FDA for use in Magnetic Resonance Imaging. The most commonly utilized contrast agents contain gadolinium and have distribution properties similar to iodinated IV contrast agents typically used for CT scans, IVPs and arteriography. Gadolinium helps to enhance contrast differences between normal tissue and tumors or inflammatory processes in the abdomen and pelvis. However, there is no iodine in gadolinium containing contrast agents, and thus, gadolinium enhanced MRI of the kidneys, liver, pancreas, or gynecologic structures may be substituted for CT scanning in patients with iodinated contrast allergies. Gadolinium also improves the vascular signal in 3D MR angiography, a newer noninvasive way to evaluate the aorta and peripheral vessels. Another MRI contrast agent which contains super paramagnetic iron oxides (SPIOs) has recently been approved by the FDA specifically for use in the liver. This compound is taken up by the reticuloendothelial system and makes normal hepatic tissue dark on T2 sequences, allowing liver metastases or primary tumors to stand out brightly against the dark background. Other types of hepatic and blood pool specific contrast agents are undergoing clinical trials, but are not presently available for use.
Q: What is the role of MR in evaluating recurrent cervical CA?	Because of innate tissue contrast, or signal differences in the endometrial, myometrial, and parametrial structures brought out by T2 sequences, MRI is much more accurate than either CT or physical exam combined with IVP for staging cervical carcinoma. Recent studies have shown that when MRI is the first study used to evaluate patients, money is saved and more invasive diagnostic procedures are avoided. For evaluation of patients with suspected recurrent carcinoma of the cervix, MRI with gadolinium enhancement is useful for differentiating post radiation fibrosis (which often appears mass-like) from recurrent neoplastic tissue.
Q: What is the role of MR in evaluating liver tumors?	Again because of innate contrast differences between normal hepatic parenchyma and most neoplastic tissue, tumor detection rates with MRI are similar to those with contrast enhanced CT. Adding gadolinium contrast enhancement to the MRI protocols often enables better characterization of the lesion or lesions. The multiplanar capability of MRI may also better delineate the relationship of the tumor to adjacent structures such as hepatic vessels or the diaphragm, and is helpful for surgical planning. Early trials have shown SPIO agents to be as accurate as CT portography in the detection of hepatic metastases; this type of examination may eventually replace standard contrast enhanced CT in screening for metastases, or be required prior to surgical therapy for hepatic metastases. Some centers routinely use MRI for evaluation of the liver in cirrhotic patients. At UAB, we utilize MRI to solve questions left unanswered by CT in these patients, but we do preferentially perform MRI of the liver in hemochromatosis patients as well as in patients who cannot receive the iodinated contrast which is necessary to evaluate the liver with CT.
Q: What is the role of MR in evaluating pancreatic disease?	Gadolinium enhanced MRI has been used to evaluate patients with pancreatic carcinoma prior to surgical resection. MRI readily identifies lymph node or liver metastases similar to CT scanning, but MR angiography sequences also provide more detailed information regarding the vessels surrounding the pancreas in determining local resectability. At UAB, we have studied the use of MRI to evaluate the pancreas in patients with severe, necrotizing pancreatitis to establish the feasibility of nonsurgical drainage. In the near future we plan to study the accuracy of gadolinium enhanced MRI compared to the standard, contrast enhanced CT in establishing the presence of pancreatic necrosis, and subsequently a hospitalization cost effective comparison of the two modalities will also be undertaken.
Q: What advantage can MR offer in evaluating biliary disease?	Magnetic resonance cholangiopancreatography, or MRCP, has developed over the past two years into an effective tool for evaluating the bile and pancreatic ducts. In some academic centers, MRCP has substantially displaced diagnostic ERCP. Studies have shown that MRCP is equivalent to diagnostic ERCP in detecting the level as well as the etiology of bile duct obstruction. MRCP is equivalent to ERCP and better than ultrasound for the detection of common bile duct stones. There are several methods used to obtain MRCP images, which look very similar to spot radiographs obtained during standard ERCP. Because the MRCP images are acquired during breath holds ranging from 7 seconds to 35 seconds on the MRI scanners at The Kirklin Clinic and University Hospital, this exam takes only 10 minutes to perform. However, unlike ERCP, no sedation of the patient is necessary and the procedure is completely noninvasive.
Q: How can MRI be used to evaluate the pregnant patient?	Because no ionizing radiation is used for MRI, it is the cross sectional imaging modality of choice in pregnant women. MRI is often used to evaluate abdominal or pelvic masses in pregnant patients, particularly during the second trimester when surgical options are contemplated. Certain MRI protocol modifications are made to lessen the energy deposited within the patient during the MRI scan, and we generally refrain from using gadolinium enhancement as there has been no testing of its affects on the human fetus. MRI is often used specifically to evaluate complications of pregnancy such as rapidly enlarging leiomyoma or adnexal masses, uterine dehiscence, and congenital uterine malformations.
Q: How do I schedule an outpatient for body or musculoskeletal MRI?	The telephone number for MRI scheduling at TKC is 731-9380. When calling this number, be prepared to hold for possible several minutes while scheduling personnel answer other calls.
Q: What if I need to schedule an patient who needs anesthesia, extensive pain control, etc requiring more than PO medications?	These patients will be scanned at the West Pavilion with the assistance of the Anesthesiology Department. Call 934-2796 to discuss the patient with the MRI technologists. A patient information form will need to be completed and Faxed to MRI. The case will then be scheduled with Anesthesiology. You will need to call one Day Surgery (934-2627) to schedule admission of your patient in order to obtain monitoring after the procedure.
Q: What if I need to schedule a patient for a body or musculoskeletal MRI to be done more quickly that routine scheduling will allow?	Please call the body or musculoskeletal radiologist scheduled to cover MRI on that day and discuss the case. We will try to accommodate reasonable requests. If you have difficulty contacting the scheduled MRI radiologist, please page any of the Body MRI faculty Therese Weber, Phil Kenney, Jay Listinsky, Kevin Smith, Desiree Morgan, or Brian Jones.
Q: How do I schedule an inpatient for body or musculoskeletal MRI?	Call 934-2796 and discuss the patient with the technologists prior to generating a computer request. Factors to keep in mind when scheduling an inpatient for MRI include that: 1) the patient will be capable of holding still for the examination. Motion artifact degrades the images. 2) the patient weighs less than 300 lb and will fit within the bore of the scanner 3) the patient is able to lie flat and breath evenly. Panting respiration again will cause extensive motion artifact which will degrade the images 4) the patient does not have any contraindications for MRI There are several conditions that will automatically exclude patients from having a MRI exam. These would include: 1. cardiac pacemaker 2. pacer wires from a prior pacemaker 3. cranial aneurysm clips 4. implanted infusion pumps, TENS units, etc. Other circumstances that may or may not exclude a patient from having a MRI exam should be addressed prior to scheduling the MRI appointment and include: 1. history of metal in the eyes. This should be excluded by appropriate radiographs. 2. cochlear implants: most are unsafe to scan 3. penile implants: some are unsafe to scan 4. artificial heart valves: while most are safe to scan, there are a couple which are not. 5. insurance precertification: some insurance companies require that MRI exams be approved prior to being done.