Laboratory of radionuclide diagnostics

Chief of the dept. Tatjana A. Larionova

Research area investigation of conditions of osteogenesis and blood circulation after fractures and limb lengthening investigation of regenerated tissue's mineralization and entire skeleton investigation of lymph nodes and lymph flow in the extremity after trauma and its lengthening valuation of functional condition of marrow endocrine regulation of reparative osteogenesis valuation of functional condition of gastrointestinal tract (liver, gallbladder) valuation of kidney function, especially in purulent infection

About our laboratory

Nowadays it is actual to find out age-related changes of skeleton mineralization of almost healthy people to use these data as normal in prophylaxis of fractures in aged patients and senility. One of main objectives is to carry out complex of measures in prophylaxis of fractures, which consist of prescription of sex hormones in small dosage, Ca with vitamin D3 and specific preparations, developed in our Center. The laboratory carries out all necessary investigations on the instructions of physicians. Particularly, different investigation with use of marked compounds are carried out. For such procedures standard special preparations are used, which are accumulated selectively in bones, either circulate in vessels or move with flow of interstitial fluid. To determine the location of the compoud it is marked previously with Tc-99m (technecium), that guarantees minimal radiation dose.

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One of examined indexes is characteristics of condition of distracted regenerated tissue. Unripe regenerated tissue is poor mineralized. Therefore it accumulates much of osteotropic compound (pic.1 - scanning image of tibia after 4 weeks of distraction and after 6 weeks of fixation), but as mineralization finishes the intensity of its accumulation decreases (pic.2 - scanning image of cannon-bones after 4 weeks of distraction and after 6 months apparatus had been removed).

Our laboratory investigates mineral density of bones after fractures and trauma already 30 years. Essential attention is payed to early detection, prophylaxis and treatment of osteoporosis. Now Ural database of age-related changes of mineral density is created, which will allow to compare mineral density of every person according to standard of local region, but not according to foreign standards.

The condition of blood circulation in extremity is quite important for regeneration. It is detected by different methods. One of them is the following: after intravenous injection of necessary diagnostic preparation researcher detects how much time it takes the preparation to reach, for example, capillaries of big toe, i.e. reveals the speed of preparation flow in the greater circulation. This index is extremely important for physician. If a patient suffers from atherosclerosis or endarteritis blood flow meets resistance and the speed of preparation flow decreases.

Another method is following: researcher injects preparation in the muscle and detects how much time it takes the preparation to leave the place of injection. When blood flow is disturbed the preparation leaves the place of injection slowly. As a result physician receives the information about the volume of blood which passes the muscle in a definite period. There are preparations that do not leave circulatory system that appears to be an important index of blood circulation and structure of extremity's circulatory system (pic.3). Vital importance has the detection of duration of period of capillaries' filling and total volume of capillaries (pic.4).

pic.3-4 Graphical record of blood volume in foot capillaries in patient, suffered from endarteritis (III stage of ischemia).
Injured extremity (lower curve A) has volume considerably decreased	Three months later after stimulation of blood supply the curve A draw to norm.

Radionuclide methods are widely used in diagnostics of different kinds of pathology. Below there are two examples of reparative process control. First displays the dynamics during the treatment of deforming arthrosis by repeated osteoperforations (pic.5). The treatment considerably enhanced condition of knee joint.

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The second example displays changes of mineral density of spine during deformity treatment.

Densitograms of patient, suffered from spondylolisthesis L5
before operation density is increased on the level of instability	3 months after apparatus was installed decreased density is on the level of discotomy	1.5 years after the apparatus removement the increasing of mineral density is displayed

Before treatment it is very important to evaluate the speed of fluid's outflow from tissues. To detect this index preparations with the smallest particles are used, therefore, they are easily moved by natural flow of interstitial fluid, revealing its speed. Due to this the probability of swelling is excluded. Lymph accumulates and flows by several manifolds (three of them are on the upper extremity, four - are on the lower one). There are no any data about the speed of lymph flow. Our laboratory could detect how lymph penetrates into capillaries and how their valves functionate.

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Fig. 1. Examination of a patient. Bone densitometer Lunar DPX-NT: a)Position of a patient on the table of the device. b)Densitogram in the mode Total Body.
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Fig. 2. Densitogram of patient, 22 y.o. Estimation of bone mineral density using Custom function: a) system in skeleton, b) locally in projection of a aregenerate

In the case of lengthening the reduction of mineral density in the area of the regenerate by the 60th distraction day is compensated by intensive augmentation of bone density in the period of fixation (60-80 days). Once the frame is removed, bone mineral density in the regenerate continues to grow.

Fig. 3. Bone mineral density in the regenerate area in patients undergoing tibial lengthening

We also carry out examination of heart function and functional condition of stomach, liver, gallbladder and kidneys.