NEAR INFRARED LIGHT AS AN INNOVATIVE TOOL FOR A THREE-DIMENSIONAL EVALUATION OF THE SUPERFICIAL VENOUS SYSTEM AND OF THE VEINS PERFORATING THE DEEP MUSCULAR FASCIA OF LOWER LIMBS
- The Chemiometry is a new imaging language that allows the visualization of the pathological venous refluxes of the incontinent perforating veins located in the anatomy between the muscular fascia and the epidermis with a three-dimensional view. Many are the human tissues which contain various bio-molecular components that can draw in or reflect the wavelength of the near infrared light. This allows an high definition physio-pathological imaging.
- Approaching the Phlebology with the Chemiometry is really interesting. The absorption of the near infrared light is in a spectrum relationship with the deoxy-haemoglobin of the blood cells. It’ s already applied, due to its various implications, in a lot of scientific fields and also by some Phlebologists. With the Chemiometry we can reconstruct the superficial venous flux, as in a high definition phlebography: imaging of vessels until 0.15 mm and hair bulbs until 60 micron.
- The Chemiometry construct an imaging with a mathematical model applied to the spectroscopical science, according to a one-to-one correspondence with the not visible infrared light and independent from the operator. We have to consider that the majority of the therapeutic or imaging procedures on the pathological venous reflux are performed above the muscular fascia and that the wavelength, through the atmosphere, of the visible light is between 380 and 750 nm.
It’s well known that in the visible light spectrum the oxygenated blood has a red color, the venous blood is blue instead. At 760 nm there is a significant spectrum absorption in the superficial venous reflux.
While the wavelength peak of the near infrared light given out by the viewer is 760 nm, when it’s given out by the same viewer on the skin the wavelength becomes 530 nm, in the green layer.
SLIDE B (paziente sana)
This is the typical imaging of an healthy patient, with intact valves and without venous refluxes. The patient is 22 years old, 1.74 mt tall and 62 kg weight. This imaging shows a succession of various green reflection areas in a intact muscular fascia. The holes, which cross the fascia and through which run perforating veins, nerves and lymphatic vessels, are intact, without loosening. The reflection area, in this case, can appear homogeneously green because of the reflection of the collagen amino acids without polarity.
Only the valves opening, while stretching or flexing the calf, allows the visualization of the continent perforating veins.
In accordance with theory of the one-to-one relationship sets, we will call A the set of non observable photons and B the set of the visible photons projected in a rectangular area.
They will appear green when reflected by the muscular fascia and black when the near infrared light of the viewer will be absorbed by the iron present in the non-oxygenate haemoglobin (deoxy–haemoglobine).
The variability (the difference) between standing and sitting position is not influent and the evaluation is not affected by the operator but only by the due calibration of the viewer.
SLIDE C (paziente con perforanti)
In the imaging of patients with perforating veins pathology, we will point out a circular absorption due to the morbid venous reflow of the fascial perforating veins.
This little areas appear in black due to the absorption of the near infrared light by the deoxy-haemoglobin. In this way the surrounding fascial plane is identified in green due to the reflexion of infra red light by the amino acids belonging to the strong muscular fascia.
The muscular fascia assure a main anatomical and physiological barrier between the superficial and the deep nervous system.
The muscular fascia presents several little holes and a multiple plains structure set up by collagen triple-helical fibres and differently oriented depending on the different planes, which are parallel among them.
According to spectroscopy this white and multifaceted plane is principally constituted by collagen amino acids with high electrostatic polarization index.
Among them, more then one-third is constituted only by glycine amino acids. His apolar, white crystal-looking is, from the optical point of view, neutral to the spectrum reflection of the light at 760 nm.
Considering the near infrared light, this will ensure a high reflection index of the non-visible light in the infra-red spectrum.
A meta analysis carried out on 180 patients between March 2009 and March 2010 shows that the refraction index of the near infrared light is only due to the muscular fascia. The image of this is equivalent to the veins perforating the muscular fascia allowing us to measure the penetration of the of the non-
visible light. The muscular fascia is white and, in the lower limbs, is very thick and strong in order to assure the best anelastic resistance. Thanks to the ecoduplex methodology we can see the perforating veins and their deepness using the muscular fascia as reflecting plane. In this way we can obtained two group of patients depending on their build.
In 120 of the patients studied, the reflecting fascia was at about 10 mm in depth, while in the remaining 60 patients the muscular fascia was seen between 15 and 20 mm in depth. In this study we cannot include strongly fat patients.
In these cases we have to consider an increase of the light scattering phenomenon due to the small size of the particles.
With the near infrared light and so the chemiometric imaging we can lay the basis for a new common language among radiologists, phlebologists, vascular surgeons and patients thanks to an easy and accurate examination.
Chemiometry puts into correlation the wavelengths, allowing the identification of the pathological venous refluxes in the anatomy above the fascia.
Considering the quantitative chemical value of the superficial venous reflux reduces the operator’s influence in the eco duplex methodology because is no more necessary performing the standard manoeuvres required in order to obtain velocity and flux direction when we cannot register them. In conclusion, this kind of analysis of the pathological venous refluxes, besides the clear imaging of the incontinent perforating veins, confirms their functional importance.
L’ articolo del Dott. Marco Cosimi sulla chemiometria con near infrared light e il suo apporto diagnostico in ambito flebologico è stato selezionato tra i migliori 12 articoli del congresso mondiale dell’ American College of Phlebology 2010 in florida Orlando, ed esposto per i colleghi nella hall congressuale per 5 giorni.