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Odd Job
06-19-2006, 06:03
@ SS

I need to have a part of this discussion put to bed.....the x-rays of the ammo explain the dispersion pattern not the lethality if you are trying to compare to conventional ammunition x-rays.

I agree fully. It is the dispersion and the final configuration of fragments that I am interested in, in lieu of seeing them in gel.

I have alot of x-rays of people shot in the head, chest, face, abdomen, extremities that are very much alive and I can put 2 x-rays side by side (one patient alive, the other one dead) and it tells nothing of the wound ballistic characteristics other than a 2 dimensional idea of where the bullet is.

Agreed and ditto. The X-rays don't indicate fully the nature of the injuries. If this was the case there would be no need for clinical diagnosis, it would all be radiological. Primary and secondary surveys in the resus room would be replaced by a Lodox Statscan and a radiologist. Never gonna happen. However, you must surely agree with me that the production of daughter fragments is likely to produce more wounding than if the projectile remains intact, provided that such secondary projectiles have the ability to penetrate and damage structures of vital importance. That would be what separates this LeMas ammunition from something like a Glaser for instance. The final distribution of these fragments indicates their potential to cause damage, even though the nature of the damage may not be fully described by means of radiology. That is what I am interested in: the potential of the ammunition to wound.

The idea of using x-rays to determine anything else is negated by the fact that we don't have 64 slice CT scan images to see all of the tiny metallic fragments (dust) disperses in the tissues in a manner that reveals useful information.

I am not sure that CT would be the best modality to detect metallic fragments of 'dust' size. Certainly single emulsion X-ray film has far better resolution for that purpose. Perhaps something along the lines of mammography film or very detailed extremity film/screen combination. A mammography film can detect the smallest opacities: if it can resolve micro-calcs I am willing to bet it will detect micro-dust of a metallic nature. The limitation would be film size and the tissue for analysis would have to be sectioned carefully because there is a thickness limitation at those low penetration voltages.
Ordinary films: I have not ever seen the 'dust' that you speak of: in all the cases I have seen the projectile fragments have been detectable on X-ray as long as they are lead. I would estimate the smallest size lead fragment I can detect on film/screen combinations as found in an ER setting to be sub-millimetre in size. (I have numerous examples of this and I can provide them here if necessary.) However if this LeMas ammunition produces smaller fragments then the imaging required to demonstrate that may have to be very precise indeed. I haven't seen the X-rays (not ones I feel do LeMas or me any favours at any rate) so I will have to reserve comment until then.

The x-rays I do have of the LeMas ammo simply shows wide scatter of the particles...

Well that is good news because it tells me that standard imaging CAN detect these fragments, unless I have misunderstood you. The distribution of these fragments is of great interest to me.

you need to see and touch the tissue to really appreciate the effects that are germain to this discussion. X-rays are again a small piece of the puzzle that make up the entire picture of the LeMas injury pattern in tissue.

I agree that X-rays are not 100% going to document the effects of the projectile. After all much of the damage is not detectable on film as an obvious opaque or lucent phenomenon. Vascular damage in particular, as you know, is very difficult to nail down by radiology alone unless the bleed is substantial or it has a gross compression effect on nearby anatomy. However, given the nature of the fragmentation of these LeMas projectiles and the fine distribution of ultrafine particles I have to say that purely from a projectile fragment distribution view point, X-ray imaging has to be more sensitive to the detection of these particles than a macroscopic surface study. What I mean is that no matter how detailed your invasive inspection is, you cannot visually make contact with all the projectile fragments. Once again there is a real-life scenario that supports my statement: the autopsy of the gunshot victim. The reason why they are all X-rayed is because it is understood that no matter how thorough the autopsy is, the detection of projectile fragments by means of autopsy is not 100% sensitive. It just cannot be. You would have to slice the victim in a bacon slicer and produce slices of sub-millimere thickness to detect all of the fragments without X-rays. And if you have not visually pinpointed all of the projectiles, you will (by definition) have failed to document the entire wound track of that projectile fragment.

So in this case, where gel is excluded and the test tissue is opaque and you are specifying fine projectile fragments, X-rays are of paramount utility in the discussion of the effects and terminal configuration of this LeMas projectile.

Edit: nice CT scan there. I have seen enough of those also, to say that the patient could easily survive that. I have a case very similar to that in my file (no 3D recon though) and the patient survived, although he did have a prolonged stay in hospital because of an iatrogenic infection.

APLP
06-19-2006, 14:07
Sample performance in ballistic gelatin and living tissue for the Le Mas 5.56 Short Range Armor Piercing LW is shown below.

APLP
06-19-2006, 14:13
Same animal, same gelatin block penetration as previous post is shown below.

APLP
06-19-2006, 14:42
Mr. Roberts published the Le Mas SRAP 5.56 UW / SD gelatin block performance data in March 2002 shown in the below left attachement in March 2002. Mr. Roberts has repeatedly remarked that that the Le Mas Ltd. 5.56 UW bullet lacked sufficient penetration unless the target was the size of a small furry squirrel.

The accompanining Le Mas Ltd. SRAP 5.56 UW gelatin block impact data was provided by HP White Labs.

Odd Job
06-19-2006, 17:15
@ APLP

Are there originals of those X-ray films? There are too many compression artefacts for me to see what's going on with the fragments. The other thing is were the X-rays taken before SS opened the pig or after?
The compression artefact can be seen here in the image I have zoomed and marked:

http://i55.photobucket.com/albums/g154/Odd_Job/15_Xray_LW556.jpg

The yellow arrows point to image artefact or 'bleed' that was either caused by aggressive jpeg compression or colour aliasing (reduction of the number of colours in the image palette). That degree of compression artefact makes analysis of fine projectile fragment densities almost impossible. One curious thing I found in that AP/PA view of the pig's thorax is a linear parallel distribution of projectile fragments. I have outlined that in orange. I am puzzled by that...is it an artefact? I am guessing it is because it is at right angles to the indicated direction of projectile travel and is 'too straight' if you know what I mean.

The other image is good enough for me to work out the anatomy, but only because there are obvious landmarks:

http://i55.photobucket.com/albums/g154/Odd_Job/17_Xray_LW556.jpg

The small red circle added to the image therefore covers the foreleg/shoulder area of the animal as well as the upper thorax. That is an educated guess, I'm not a veterinary radiographer but the position of the spine and the tapering of the sternum is very helpful and I reckon I am right (but apologise if I am wrong). It is very difficult to comment further though, and if I am truly objective I must say I can't really use those radiographs.

The overall penetration of the projectile in the gel is obvious in the photos but there has been some sort of manipulation (whether intended or not) between the wide and close views of the gel block. The close views have an artificial grain to them, and this could also be due to file compression. It is difficult therefore to determine which black specks are projectile fragments and which are artefacts. Evidence of the artefactual nature of those images can be found when comparing the graduations on the ruler from the wide and close view images. The close images are very noisy.

But what I would really like to see are images of the 9mm ammunition. I am keen as mustard to see those...

APLP
06-19-2006, 19:22
@ APLP

Are there originals of those X-ray films? There are too many compression artefacts for me to see what's going on with the fragments. The other thing is were the X-rays taken before SS opened the pig or after?
The compression artefact can be seen here in the image I have zoomed and marked:

http://i55.photobucket.com/albums/g154/Odd_Job/15_Xray_LW556.jpg

The yellow arrows point to image artefact or 'bleed' that was either caused by aggressive jpeg compression or colour aliasing (reduction of the number of colours in the image palette). That degree of compression artefact makes analysis of fine projectile fragment densities almost impossible. One curious thing I found in that AP/PA view of the pig's thorax is a linear parallel distribution of projectile fragments. I have outlined that in orange. I am puzzled by that...is it an artefact? I am guessing it is because it is at right angles to the indicated direction of projectile travel and is 'too straight' if you know what I mean.

The other image is good enough for me to work out the anatomy, but only because there are obvious landmarks:

http://i55.photobucket.com/albums/g154/Odd_Job/17_Xray_LW556.jpg

The small red circle added to the image therefore covers the foreleg/shoulder area of the animal as well as the upper thorax. That is an educated guess, I'm not a veterinary radiographer but the position of the spine and the tapering of the sternum is very helpful and I reckon I am right (but apologise if I am wrong). It is very difficult to comment further though, and if I am truly objective I must say I can't really use those radiographs.

The overall penetration of the projectile in the gel is obvious in the photos but there has been some sort of manipulation (whether intended or not) between the wide and close views of the gel block. The close views have an artificial grain to them, and this could also be due to file compression. It is difficult therefore to determine which black specks are projectile fragments and which are artefacts. Evidence of the artefactual nature of those images can be found when comparing the graduations on the ruler from the wide and close view images. The close images are very noisy.

But what I would really like to see are images of the 9mm ammunition. I am keen as mustard to see those...

Odd Job,
Those are pictures of the oringinal X-rays from a different shoot, but are typical of what is seen with each bullet deployment. The x-rays from the shoot Dr. Vail attended are not available for posting. There will be another event in the near future where similar data can be posted, and if digital equipment is on site the transmission and recordings will be easily shared.

The yellow is bleed, the orange area as you have identified is an accurate depiction of bullet particulate distribution patterns, and you are also correct with respect to the immediate bullet particulate at right angles to the bullet trajectory. You have guessed your anatomy correctly.

All of the black specs are bullet particulate. HP White Labs labeled those particles as dust particles. It is reasonable to assume some of the bullet particulates escaped the overall dimensions of the gelatin block.

Doc
06-19-2006, 19:44
It was brought to my attention we needed to split this thread from the original. I went back to the start of the radiological discussion posted by Odd Job and decided that this new thread starts there.

Carry on. :munchin

Odd Job
06-20-2006, 02:00
@ APLP

The x-rays from the shoot Dr. Vail attended are not available for posting.

When they are available or when another test is done, I will be back.