acr–asnr practice guideline for the performance of myelography and ...

The American College of Radiology, with more than 30,000 members, is the principal organization of radiologists, radiation oncologists, and clinicalmedical physicists in the United States. The College is a nonprofit professional society whose primary purposes are to advance the science of radiology,improve radiologic services to the patient, study the socioeconomic aspects of the practice of radiology, and encourage continuing education for radiologists,radiation oncologists, medical physicists, and persons practicing in allied professional fields.The American College of Radiology will periodically define new practice guidelines and technical standards for radiologic practice to help advance thescience of radiology and to improve the quality of service to patients throughout the United States. Existing practice guidelines and technical standards willbe reviewed for revision or renewal, as appropriate, on their fifth anniversary or sooner, if indicated.Each practice guideline and technical standard, representing a policy statement by the College, has undergone a thorough consensus process in which ithas been subjected to extensive review, requiring the approval of the Commission on Quality and Safety as well as the ACR Board of Chancellors, the ACRCouncil Steering Committee, and the ACR Council. The practice guidelines and technical standards recognize that the safe and effective use of diagnosticand therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the publishedpractice guideline and technical standard by those entities not providing these services is not authorized.ACR–ASNR PRACTICE GUIDELINE FOR THE PERFORMANCE OFMYELOGRAPHY AND CISTERNOGRAPHYRevised 2008 (Resolution 20)*PREAMBLEThese guidelines are an educational tool designed to assistpractitioners in providing appropriate radiologic care forpatients. They are not inflexible rules or requirements ofpractice and are not intended, nor should they be used, toestablish a legal standard of care. For these reasons andthose set forth below, the American College of Radiologycautions against the use of these guidelines in litigation inwhich the clinical decisions of a practitioner are calledinto question.The ultimate judgment regarding the propriety of anyspecific procedure or course of action must be made bythe physician or medical physicist in light of all thecircumstances presented. Thus, an approach that differsfrom the guidelines, standing alone, does not necessarilyimply that the approach was below the standard of care.To the contrary, a conscientious practitioner mayresponsibly adopt a course of action different from thatset forth in the guidelines when, in the reasonablejudgment of the practitioner, such course of action isindicated by the condition of the patient, limitations ofavailable resources, or advances in knowledge ortechnology subsequent to publication of the guidelines.However, a practitioner who employs an approachsubstantially different from these guidelines is advised todocument in the patient record information sufficient toexplain the approach taken.The practice of medicine involves not only the science,but also the art of dealing with the prevention, diagnosis,alleviation, and treatment of disease. The variety andcomplexity of human conditions make it impossible toalways reach the most appropriate diagnosis or to predictwith certainty a particular response to treatment.Therefore, it should be recognized that adherence to theseguidelines will not assure an accurate diagnosis or asuccessful outcome. All that should be expected is that thepractitioner will follow a reasonable course of actionbased on current knowledge, available resources, and theneeds of the patient to deliver effective and safe medicalcare. The sole purpose of these guidelines is to assistpractitioners in achieving this objective.I. INTRODUCTIONThis guideline was revised collaboratively by theAmerican College of Radiology (ACR) and the AmericanSociety of Neuroradiology (ASNR).Myelography has been an important diagnostic modalityfor a wide range of spinal disease processes for more than80 years. Cisternography using intrathecal contrast mediahas also been used for many years in the diagnosticevaluation of disease processes involving the basalcisterns and skull base.These procedures typically involve performance of alumbar puncture under fluoroscopic guidance followed bythe fluoroscopically monitored introduction into thesubarachnoid space of a nonionic water soluble iodinatedcontrast medium that is FDA approved for intrathecaladministration. Alternatively, when the lumbar approachis contraindicated or less advantageous, the contrastmedium may be introduced into the thecal sac via a lateralC1 to C2 puncture, which is described in section V.C.9.Following the introduction of a sufficient quantity ofintrathecal contrast medium, the needle is withdrawn.With the aid of a tilting table, the opacified cerebrospinalfluid (CSF) is positioned in the desired region of thePRACTICE GUIDELINE Myelography / 1

spinal subarachnoid space (lumbar, thoracic, or cervical)or in the intracranial basal cisterns, and appropriateradiographic/fluoroscopic (conventional myelogram)and/or computed tomographic (CT) myelogram orcisternogram images are obtained.Institutions offering myelography should insist ondocumentation of appropriate training, demonstratedcompetence, and maintenance of skills for all physicianswho receive privileges to perform these procedures.II.INDICATIONSAlthough myelography and cisternography have largelybeen superseded by the development of high resolutionCT and magnetic resonance imaging (MRI), there remainthe following indications for these procedures:1. Demonstration of the site of a cerebrospinal fluidleak (postlumbar puncture headache, postspinalsurgery headache, rhinorrhea, or otorrhea).2. Surgical planning, especially in regard to thenerve roots.3. Radiation therapy planning.4. Diagnostic evaluation of spinal or basal cisternaldisease.5. Nondiagnostic MRI studies of the spine or skullbase.6. Poor correlation of physical findings with MRIstudies.7. Use of MRI precluded because of:a. Claustrophobiab. Technical issues, e.g., patient sizec. Safety reasons, e.g., pacemakerd. Surgical hardwareFor the pregnant or potentially pregnant patient, see theACR Practice Guideline for Imaging Pregnant orPotentially Pregnant Adolescents and Women withIonizing Radiation.III.A. PhysicianQUALIFICATIONS ANDRESPONSIBILITIES OF PERSONNELCertification in Radiology or Diagnostic Radiology by theAmerican Board of Radiology, the American OsteopathicBoard of Radiology, the Royal College of Physicians andSurgeons of Canada, or the Collège des Médecins duQuébec, and the performance of myelography withacceptable success and complication rates.orCompletion of a residency or fellowship training programapproved by the Accreditation Council for GraduateMedical Education (ACGME), the Royal College ofPhysicians and Surgeons of Canada (RCPSC), the Collègedes Médecins du Québec, or the American OsteopathicAssociation (AOA) to include evidence of training andcompetency in myelography. Adequate training shouldinclude the performance of a sufficient number ofmyelographic procedures to become facile in thetechnique.andInstruction in all of the following areas should besubstantiated by the director of the training program:1. Anatomy, physiology, and pathophysiology ofthe central and peripheral nervous systems.2. Physics of ionizing radiation, including anunderstanding of its production, detection, andrisks, and of techniques to minimize radiationexposure.3. Pharmacology and dosage of contrast media usedin myelography. (Use of only those agentsapproved for intrathecal use should beemphasized.)4. Indications for myelography and cisternography.5. Preprocedural assessment of the patient.6. Conduct of the myelographic examination. Thisincludes spinal puncture, patient positioning, andfluoroscopic and filming techniques.7. Conduct of the postmyelogram CT examination.This includes timing, patient positioning, andtechnical factors.8. Postprocedural patient management, especiallythe recognition and initial management ofcomplications.9. Interpretation of lumbar, thoracic, and cervicalmyelograms and cisternograms, as well asinterpretation of postmyelogram CT scans.10. Contraindications to myelography.11. Knowledge of the drugs that can increase risk ofmyelographic adverse events.Maintenance of CompetenceTo maintain privileges, physicians must perform asufficient number of myelographic procedures to maintaintheir skills with acceptable success and complicationrates.Continuing Medical EducationContinuing education should be in accordance with theACR Practice Guideline for Continuing MedicalEducation (CME).B. Registered Radiologist AssistantA registered radiologist assistant is an advanced levelradiographer who is certified and registered as aradiologist assistant by the American Registry ofRadiologic Technologists (ARRT) after havingsuccessfully completed an advanced academic programencompassing an ACR/ASRT (American Society of2 / Myelography PRACTICE GUIDELINE

Radiologic Technologists) radiologist assistant curriculumand a radiologist-directed clinical preceptorship. Underradiologist supervision, the radiologist assistant mayperform patient assessment, patient management andselected examinations as delineated in the Joint PolicyStatement of the ACR and the ASRT titled “RadiologistAssistant: Roles and Responsibilities” and as allowed bystate law. The radiologist assistant transmits to thesupervising radiologists those observations that have abearing on diagnosis. Performance of diagnosticinterpretations remains outside the scope of practice of theradiologist assistant. (ACR Resolution 34, adopted in2006)C. Radiologic TechnologistCertification by the American Registry of RadiologicTechnologists or unrestricted state licensure is required.In addition, the radiologic technologist should havetraining in and be skilled in performing fluoroscopicexaminations on patients with intrathecal contrast media,including patient positioning, fluoroscopic beamlimitation, and methods of applying safe physical restraintduring table tilting. Continuing education programs andon-the-job training under the supervision of qualifiedphysicians should be available.IV.EQUIPMENT SPECIFICATIONSA. Myelographic FacilityThe minimum requirements for the facility are:1. High-quality radiographic/fluoroscopic imagingequipment, film or digital records of theexamination, and a tilt table. The tilt table shouldbe capable of –30 degrees of tilt in the headdownward direction. A proper support device forsecuring the patient on the tilt table should beavailable.2. An adequate selection of spinal needles andappropriate nonionic contrast media approved forintrathecal use.3. Appropriate facilities and equipment for treatingadverse reactions (e.g., seizure, vasovagalreactions, and/or cardiorespiratory collapse).4. Appropriately trained personnel to provideproper patient care and operation of theequipment.5. A CT scanner to perform postmyelogram CTstudies. Multiplanar reconstruction capability forCT is highly desirable.B. Surgical and Emergency SupportAlthough serious complications of myelography areinfrequent, there should be prompt access to surgical andinterventional management of complications.V. SPECIFICATIONS OF THEEXAMINATIONA. Preprocedural Patient CareThe written or electronic request for myelography shouldprovide sufficient information to demonstrate the medicalnecessity of the examination and allow for its properperformance and interpretation.Documentation that satisfies medical necessity includes 1)signs and symptoms and/or 2) relevant history (includingknown diagnoses). Additional information regarding thespecific reason for the examination or a provisionaldiagnosis would be helpful and may at times be needed toallow for the proper performance and interpretation of theexamination.The request for the examination must be originated by aphysician or other appropriately licensed health careprovider. The accompanying clinical information shouldbe provided by a physician or other appropriately licensedhealth care provider familiar with the patient’s clinicalproblem or question and consistent with the state scope ofpractice requirements. (ACR Resolution 35, adopted in2006)The clinical history and findings are to be reviewed by theperforming physician.1. Prior to myelography, any prior pertinentimaging studies, including lumbar CT or MRI,should be reviewed. The review should includeevaluation for the position of the conus, as wellas lumbar stenosis or any other potential hazardprior to choosing the level for LP or myelogram.2. The patient should be asked specific questionsabout relevant medications, prior seizures, priorallergic reactions, and clotting ability.3. Patients who are taking Plavix (clopidogrel) forprophylaxis of myocardial or cerebral ischemiashould discontinue this drug for at least 5 daysprior to undergoing myelography.4. For patients with hematologic disorders or otherconditions affecting blood coagulation, a plateletcount and international normalized ratio (INR),prothrombin time (PT), and partialthromboplastin time (PTT) values within oneweek of the procedure should be available.5. Informed consent should be obtained anddocumented. The patient should be informed ofthe risks and the benefits of the procedure.6. The patient should be adequately hydrated.7. If utilized, sedation should be administered inaccordance with the ACR–SIR PracticeGuideline for Sedation/Analgesia.PRACTICE GUIDELINE Myelography / 3

B. Relative Contraindications to Myelography1. Known significant intracranial process withincreased intracranial pressure.2. Historical or laboratory evidence of bleedingdisorder or coagulopathy.3. Recent myelography performed within 1 week.4. Previous surgical procedure in anticipatedpuncture site (can choose alternative puncturesite).5. Generalized septicemia.6. History of significant adverse reaction toiodinated contrast media.7. History of seizures (patient may bepremedicated).8. Grossly bloody spinal tap (may proceed whenbenefit outweighs risk).9. Localized infection at region of puncture site.10. Pregnancy.11. Medications known to decrease seizurethreshold, (e.g., phenothiazines, tricyclicantidepressants, monoamine oxidase inhibitors,SSRI medications) should be discontinued for atleast 24 to 72 hours prior to myelography.C. Procedure1. The patient is placed prone on the table top, andthe skin of the midlumbar back is sterilized.2. Using the lumbar approach, typically, the L2 toL3 or L3 to L4 interlaminar or interspinous spaceis localized under fluoroscopy. Subcutaneousand intramuscular local anesthetic isadministered. A styletted spinal needle isintroduced through the anesthetized region anddirected toward the midline. The needle isadvanced under intermittent fluoroscopic controlin small increments. If a beveled needle isutilized, the bevel may be used to control thedirection of the needle. When the subarachnoidspace is reached, a pop may (but not always) befelt. The stylet is slowly removed to check forcerebrospinal fluid return. Fluid may be slowlywithdrawn for laboratory studies if requested.3. A nonionic iodinated contrast medium is slowlyadministered intrathecally through the lumbarneedle under fluoroscopic control. Forexamination of the lumbar subarachnoid space,up to 17 ml of a concentration of 180 mg I/dl orup to 12 ml of a concentration of 240 mg/dl canbe injected. For examination of the thoracic orcervical spinal canal or the basilar cisterns, up to10 ml of a concentration of 300 mg I/dl is used.Generally, the total dose of iodine should notexceed 3.0 gm.4. Prior to removing the needle from the back, ananteroposterior fluoroscopic “spot” image maybe obtained and documented on film or digitalmedia.5. The needle is then removed from the back, andthe patient is secured to the table top by asupport device prior to being tilted intoTrendelenburg or reverse Trendelenburgpositions.6. Using intermittent fluoroscopy, table tilting, andpatient rotation, anteroposterior, oblique, andcross-table lateral images of the region inquestion are documented on film or digitalmedia. For lumbar myelography, if the conushave not been recently visualized by othermeans, evaluation of that area should be includedin the study.7. For cervical myelography, and in some instancesthoracic myelography, the head is hyperextendedon the neck, thus creating a lordotic “trough,”and the table is then gradually and slowly tiltedhead downward until the opacified cerebrospinalfluid “column” flows through the area of interest.The myelographic table must have adequate andsecure shoulder support for the patient’s safety.The patient’s chin is supported in a chin rest toprevent rapid ascent of the contrast into theintracranial basal cisterns. The lead-gloved handsof the technologist may also support thepositioning of the patient’s head and neck. As inthe lumbar region, anteroposterior, oblique andcross-table lateral images can be documented onfilm or digital media.8. If cisternography is requested, with the opacifiedcerebrospinal fluid “column” in the cervicalspine canal, the table is restored to the horizontalposition, and then the hyperextended head isgradually and slowly lowered (flexed) into aneutral position. Imaging for cisternography istypically obtained with computed tomography;conventional radiographic images are not usuallyobtained.9. Using the lateral C1 to C2 approach, the patientis positioned prone on the table top, and the headis secured in a neutral position. Using C-armlateral fluoroscopy, the head and neck arepositioned in the true lateral projection, and localanesthesia is administered subcutaneously andintra-muscularly in the side of the neck at a pointoverlying the posterior aspect of the C1 to C2interlaminar space immediately anterior to thespinolaminar junction line and inferior to thearch of C1. If C-arm fluoroscopy is not availableor if the patient is unable to remain in a proneposition on the tabletop but can lie quietly andcomfortably in a nonrotated lateral decubitusposition, lateral C1 to C2 puncture can beperformed using vertical beam fluoroscopy.Under intermittent fluoroscopic control, thespinal needle is advanced incrementally into the4 / Myelography PRACTICE GUIDELINE

subarachnoid space at the posterior margin of thethecal sac behind the posterior margin of theupper cervical spinal cord. Great caution withfrequent fluoroscopic monitoring should alwaysbe used during needle advancement, as the durais punctured and as the iodinated contrastmedium is cautiously and slowly injected intothe subarachnoid space. When this is completed,a fluoroscopic “spot” image may be documented,and the needle is withdrawn from the neck. Thedesired area of the opacified subarachnoid spaceis then examined and documented.10. Following completion of the examination asdescribed above, the patient is transferred to theCT scanner for appropriate CT myelographic orcisternographic imaging.D. Postprocedural CareVI.1. The patient should be adequately hydrated.2. The patient should be observed following theexamination.3. If the myelogram is performed on an outpatientbasis, the patient should be properly instructedregarding limitations following the procedure(e.g., driving).4. Instructions regarding postprocedural care,including warning signs of adverse reactions andthe possibility of persistent headaches, should begiven to the patient by a trained professional.The instructions should include arecommendation that the patient should be in thecompany of a responsible adult for 12 hoursfollowing the procedure.5. A physician should be available to answerquestions and provide patient managementfollowing the procedure.DOCUMENTATIONReporting should be in accordance with the ACR PracticeGuideline for Communication of Diagnostic ImagingFindings.VII.RADIATION SAFETY IN IMAGINGRadiologists, medical physicists, radiologic technologists,and all supervising physicians have a responsibility tominimize radiation dose to individual patients, to staff,and to society as a whole, while maintaining the necessarydiagnostic image quality. This concept is known as “aslow as reasonably achievable (ALARA).”Facilities, in consultation with the medical physicist,should have in place and should adhere to policies andprocedures, in accordance with ALARA, to varyexamination protocols to take into account patient bodyhabitus, such as height and/or weight, body mass index orlateral width. The dose reduction devices that areavailable on imaging equipment should be active; if not,manual techniques should be used to moderate theexposure while maintaining the necessary diagnosticimage quality. Periodically, radiation exposures should bemeasured and patient radiation doses estimated by amedical physicist in accordance with the appropriate ACRTechnical Standard. (ACR Resolution 17, adopted in2006 – revised in 2009, Resolution 11)VIII.QUALITY CONTROL ANDIMPROVEMENT, SAFETY, INFECTIONCONTROL, AND PATIENT EDUCATIONPolicies and procedures related to quality, patienteducation, infection control, and safety should bedeveloped and implemented in accordance with the ACRPolicy on Quality Control and Improvement, Safety,Infection Control, and Patient Education appearing underthe heading Position Statement on QC & Improvement,Safety, Infection Control, and Patient Education on theACR web page (http://www.acr.org/guidelines).ACKNOWLEDGEMENTSThis guideline was revised according to the processdescribed under the heading The Process for DevelopingACR Practice Guidelines and Technical Standards on theACR web page (http://www.acr.org/guidelines) by theGuidelines and Standards Committee of the Commissionon Neuroradiology in collaboration with the ASNR.Principal Reviewer: Stephen A. Kieffer, MDACR Guidelines and Standards CommitteeSuresh K. Mukherji, MD, ChairCarol A. Dolinskas, MDSachin Gujar, MDJohn E. Jordan, MDStephen A. Kieffer, MDEdward J. O’Brien, Jr., MDJeffrey R. Petrella, MDEric J. Russell, MDJohn L. Ulmer, MDR. Nick Bryan, MD, Chair, CommissionASNR Guidelines CommitteeErin S. Schwartz, MDM.J. Bernadette Stallmeyer, MD, PhDComments Reconciliation CommitteeHoward B. Fleishon, MD, Co-Chair, CSCHarry C. Knipp, MD, Co-Chair, CSCTimothy A. Bernauer, MDR. Nick Bryan, MD, PhDWayne L. Davis, MDPRACTICE GUIDELINE Myelography / 5

Alan D. Kaye, MDStephen A. Kieffer, MDAmy L. Kotsenas, MDDavid C. Kushner, MDPaul A. Larson, MDWalter S. Lesley, MDRichard S. Levine, MDLawrence A. Liebscher, MDSuresh K. Mukherji, MDMichael I. Rothman, MDRichard A. Suss, MDSuggested Reading (Additional articles that are not citedin the document but that the committee recommends forfurther reading on this topic)1. ACR ASRT joint statement radiologist assistant rolesand responsibilities. In: Digest of Council Actions.Reston, Va: American College of Radiology;2007:149.2. Bartynski WS, Lin L. Lumbar root compression inthe lateral recess: MR imaging, conventionalmyelography, and CT myelography comparison withsurgical confirmation. AJNR 2003;24:348-360.3. Bohn HP, Reich L, Suljaga-Petchel K. Inadvertentintrathecal use of ionic contrast media formyelography. AJNR 1992;13:1515-1519.4. Dube LJ, Blair IG, Geoffroy G. Pediatricmyelography with iohexol. Pediatr Radiol1992;22:290-292.5. Ebersold MJ, Houser OW, Quast LM. Iopamidolmyelography: morbidity in patients with previousintolerance to iodine derivatives. J Neurosurg1991;74:60-63.6. Maly P, Sundgren P, Baath L, Golman K, Walday P.Adverse reactions in myelography. Acta Radiol1995;399:230-237.7. Manual on Contrast Media Version 5. Reston, Va:American College of Radiology; 2005.8. Orrison WW, Eldevik OP, Sackett JF. Lateral C1-2puncture for cervical myelography. Part III:historical, anatomic, and technical considerations.Radiology 1983;146:401-408.9. Peterman SB. Postmyelography headache: a review.Radiology 1996;200:765-770.10. Russell EJ. Computed tomography and myelographyin the evaluation of cervical degenerative disease.Neuroimaging Clin North Am 1995;5:329-348.11. Sandow BA, Donnal JF. Myelography complicationsand current practice patterns. AJR 2005;185:768-771.12. Schick RM. Myelographic techniques. PostgradRadiol 1989;9:40-54.13. Suss RA, Udvarhelyi GB, Wang H, Kumar AJ,Zinreich SJ, Rosenbaum AE. Myelography inachondroplasia: value of a lateral C1-2 puncture andnon-ionic, water-soluble contrast medium. Radiology1983;149:159-163.14. Wang H, Binet EF, Gabrielsen TO, Rosenbaum AE.Lumbar myelography with iohexol in outpatients:prospective multicenter evaluation of safety.Radiology 1989;173:239-242.*Guidelines and standards are published annually with aneffective date of October 1 in the year in which amended,revised, or approved by the ACR Council. For guidelinesand standards published before 1999, the effective datewas January 1 following the year in which the guidelineor standard was amended, revised, or approved by theACR Council.Development Chronology for this Guideline1994 (Resolution 3)Amended 1995 (Resolution 24, 53)Revised 1998 (Resolution 6)Revised 2003 (Resolution 20)Amended 2006 (Resolution 17, 34, 35, 36)Revised 2008 (Resolution 20)Amended 2009 (Resolution 11)6 / Myelography PRACTICE GUIDELINE