03/08/03

To clarify, this series is FOR the ACR not in anyway BY the ACR.  The American Council on Radiology has published statements relating to ultrasound spinal scanning which suggests that they have grave questions relative to the physics and protocols employed to obtain meaningful images of the spine transdermally using ultrasound technology.  Since to my knowledge I have not instructed any member of the ACR this series is BY me, (Dr. John D. Reid D.C.) (the United States Patent holder for ultrasound scan to detect nerve root inflammation signs) FOR THE ACR MEMBERS to allow a confidential study by ACR members and hopefully allow an informed review to some extent, since as far as I know no ACR members have been certified by me in ultrasound spinal scanning, though some of my medical doctor, radiologist, and nuclear medicine doctor students may have gone on to train ACR members without letting me know.  

BACKGROUND: During our patent search in 1992 the professional patent team (auspices of Merchant & Gould, Minneapolis Mn.) did discover that we were in good company with 14 patents active for the BACK of the body, approximately 4 by Medtronics Inc. (One of the most respected medical corporations in the World).  The front of the BODY had received over 1,000 patents, and thus the back of the body presented somewhat of a virgin territory for discoveries and consequential patents.  Some years later after re-submission and modification the experts in the United States Patent office did grant 26 of 28 claims for my patent, and I received the US patent in 1992.  CPT codes have been in place since 1982 for most procedures employed.  Over 100 science articles supporting orthopedic ultrasound imaging were found during the patent search.  The FDA considers spinal scanning as "grandfathered" since the Picker 80L device literature in 1978 mentioned any-all body tissues and showed spinal images (non invasive, non surgical) in 1977.

I am publishing this educational series to hopefully aid the ACR to revise its opinions and discontinue spiritual opposition to  the prayers of millions of patients who every day live in pain due to confusion of diagnosis in physical medicine.   Blinded studies (without ultrasound scan)  generate statistics relative to cross correlation between Medical experts as to causes of back pain in any given patient examined as producing percentages ranging from only 6% (six percent) to 10% (ten percent) cross correlation in diagnosis.  This state of affairs is pitiful.  Even EKG is 50% reliable!  For the sake of patients and in line with the Hypocratic Oath the technology of Ultrasound Scan should be given careful study since obviously something in addition to CT, MRI, and plain film X-ray is desparately needed and PRAYED for by patients. Additionally at least 5,000 primary care practicioners, many of them Medical (directly trained by me and my students) presently employ ultrasound scan either via their own machine systems, or via mobile services.  Finally, ultrasound scan of the spine is not turf intrusive, but in all instances complementary to X-ray, MRI, and CT imaging by providing signs of Wolf's Law reactivity which make these other modalities "come alive".  Under FDA regulations (and I agree fully) ultrasound is a diagnostic adjunctive to other testing (just like MRI,CT, and plain film X-ray).  Bonne practice rarely if ever relies upon ONE diagnostic, but rather enjoys the benefit of a multitude of diagnostic tests all correlated by the treating doctor's experienced judgement.  (Note: At last check approx. 3 yrs ago X-ray still was only accepted as stand alone by the FDA in cases of bone fracture, and then only for positive fracture findings, negatives were considered unreliable since angulation effects can hide hair-lines, for all other purposes plain film X-ray was FDA classified as "adjunctive":  So, even in cases of suspected rib fracture ultrasound is useful since imaging the epicostal membrane can help find hairline fractures since the membrane swells over the fracture site no matter how small the fracture disturbance:)

LET'S BEGIN THE EDUCATIONAL PROCESS:

The anatomy is similar to MRI or CT tomography.  Spinous is toward the top of the picture, facets and body of the vertebra is below.  On average sized adults nerve roots occur at approx. the 5.5 to 6.5 cm depth level similar to MRI.  The images are "fuzzy" compared to MRI or CT but differentially echogenic directly related to inflammation reactions under Wolf's Law, and so the "fuzziness" if it can be personally tolerated by the radiologist is an extremely valuable diagnostic aspect of the images.  (Some radiologists cannot tolerate less than sharp edged images and probably should avoid ultrasound images and especially avoid spinal ultrasound images which depend upon the fuzzy edges to aid interpretations. In spinal scanning ultrasound is deeply  and fully appreciated cum ultrasound and no attempt is needed to try to force it into MRI or CT sharpness since the relatively "big fat sound waves"  of ultrasound cannot ever really match the razor sharpness of angstrom tiny X-ray photons.  In spinal scanning the BOUNCINESS of the sound waves is fully appreciated and the fuzziness is enjoyed as of great value.  X-rays of course cannot be bounced, and thus my prior statement: "ultrasound is deeply and fully appreciated cum ultraSOUND".)

The key fact is that the spine from the posterior aspect presents a relatively dry tissues challenge to penetration with ultrasound with amplitude sufficient for imaging.  This burden however also represents a potential blessing.  When frequency is dropped to 3.5 megahertz (linear transducer) penetration becomes possible. Most orthopedic structures of value are fairly large so 3.5 megahertz  with its relatively long wave length is quite useful for imaging these big structures on average sized adults.  5.0 megahertz (linear) can be employed on smaller humans or in many cases with ultra-modern high quality systems 5.0 megahertz can even be employed on average sized humans with good (modern LSC chip driven amplifiers)  penetration assurances and diagnostic value.  Large people will require 3.5 megahertz and all students are best started on 3.5 megahertz for ease of learning. The primary positioning is transverse to the course of the spine and with spinous contact and a slight upward (cephalad) aim of about 10 degrees.  L4 is a "best bet" first attempt target: Linear transducers with a slightly medial inward pinch to the interpretation computer/software algorithm are best since the facets present an "umbrella effect" which can hide nerve roots unless the algorithm can work around it with some inward pinching.   Definitions and differentiations  of value however will be lacking unless the gains are turned down to just allow an outline of the periosteum to be displayed. The periosteum absorbs sound waves, but if gains or power are too high the bone will reflect sound waves and obscure the vertebral outline, thus gains settings and power settings are critical.  On most hospital units such as ATL Mark series or the newest ATL systems power must also be turned down to 50% or less,  lest the periosteum become both penetrated (ruining the image through bone reflectivity-echogenicity) as well as stimulated.  (Periosteal stimulation is a therapeutic side effect of too high power and should be avoided unless ordered as a therapeutic approach by the treating doctor.) On hospital units the gains are left at medium settings and the power is turned down until the periosteal outline is just barely discernible, then the gain is employed (up a smidge with general gain) to enhance the periosteal outline.  finally the slice gains are all adjusted one at a time to further enhance the one through 7 cm. range vertebral (periosteal) outline. Gamma should be set for a very contrasty image with approx 25% Dark levels compaction to black and approx 25% light levels compacted to white to help definition of the periosteal outline.  (Gamma curve on a graphic resembles a 45' right tilted "S".)

The secondary key fact is that since the spinal ligaments etc. are very "dry", then histamine related fluid gathering aids penetration and definitions.  A simple rule is that normal people generate boring images with little if any details, BUT people with spine stress and or injuries generate beautiful images of high detail and minute definition.  Histamine and the consequential fluid gathering (echo permissive) as well as lymphatic dilations and repair processes (echogenic) provide a medium for ultrasound scan which becomes better and better directly related to the severity of the post traumatic repair or defense processes.  But this set of secondary principles illustrates the reasoning for labelling the technology "adjunctive" similar to X-ray, MRI, and CT. since allergies, infections, and auto immune syndromes can raise histamine levels generally (or in the case of a spinal bone infection, then the histamine levels are raised both generally and more so locally), and thus a treating doctor's clinical interpretation based upon good history and other tests as indicated is always needed.

• NOTE: Senior citizens who may have some porosis seem also to (as etiology or consequence) have thin somewhat avascular periosteum and may not present very good dark periosteal outlines, but rather present partial echogenicity from the bone surface itself thus confusing periosteal outline definition as well as surpassing the low dark gamma compaction and are the worst subjects for initial studies.

This adjunctive nature of the technology brings us to the report format considered of added value:  Reports should consist of three sections, two by radiology and a third final section by either radiology or the treating doctor.  Preceeding the "sections" THE INTRODUCTION should outline the technique, frequency, transducer type and size, and approach,  as minimas.  Then: Section #1: FINDINGS: This is usually indisputable since it should be phrased in terms of normo-echogenicity, hyperechogenicity, or hypoechogenicity.  For example "T6 reveals signs of bilateral moderate ligaments hyperechogenicity."  This would mean the ligaments appeared quite white relative to the surrounding tissues   It is social in that anyone can look at the images and agree or disagree that the ligaments appeared quite white basically, and that the gains were set correctly so a periosteal outline was noted as present.

Section #2: INTERPRETATION:  If the expert accepts that (fat laden) lymphatic dilations cause hyperechogenicity and free fluid edema as well as muscle spasms cause hypoechogenicity then the interpretation section basically is a conversion of hyperechogenicity to "inflammation signs" and hypoechogenicity converted into either "signs of edema" or "signs of muscle spasms/hypertonicity".  More perfectionistic experts might prefer "hypertonicity" to "spasm" as a term since "spasm" as a term is fairly pat, where as "hypertonicity" can be graded.  THIS SECTION IS VERY SOCIAL IN THAT AN EXPERT WHO DOES NOT ACCEPT these physiologic principles can debate the "Interpretation" section.   Spinal/paraspinal "interpretation" is now commonly employed by both Medical and other primary care doctors as based upon Wolf's Law of orthopedic stress reactivity and a high density of tiny lymphatics which service the ligaments and bones.  Anterior organ scan techniques look upon the more dispersed tiny lymphatics of the abdomen  as "clutter"  to be "imaged past/through"  in many cases and thus there is a difference in protocols, techniques, and training for anterior organ scanning verses posterior spinal scanning.  The tiny lymphatics of the near spinal structures lie along ligaments, muscle interfaces, and facet/periosteal surfaces in a very closely related and structured fashion which is valuable for diagnosis.  This is most probably related to the inability of bone and adult ligaments to self heal, but which structures require osteophytes and osteoblasts to be poured from the lymphatics in order to accomplish any repairs needed post traumatically, or defense actions needed in cases of infection.

Section #3: CLINICAL IMPRESSION:  This is where the treating doctor either disagrees with the interpretation or agrees with the interpretation and reveals his vision for clinical implications of the inflammation signs noted, as well as impact upon treatment planning.  An expert reviewer might engage this section if the treating doctor sent the patient with a somewhat wide open referral note as well as clinical records and history asking for second opinion help with clinical planning:  This is more an informative section as verses a social section since who has better knowledge of the patient day to day than the treating doctor?  HOWEVER With two scan session results on-hand (spanning a period of time between exams) this section could be employed by a second opinion expert to adjudge progress or lack of progress and recommend continuation of similar therapies or call for a consideration of a change of therapeutic course.

So, I hope I've been helpful, any questions can be directed to me via E-mail at soniclin@aol.com..... ....  detailed training courses are available, since this was just a bare outline of principles and protocols employed for Ultrasound Spine Scan (tm.):

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