One of the most severe forms of psoriasis which significantly decreases the patients' life quality is the joints damage – Psoriatic arthritis (PsA).
According to the different authors data it varies from 5 to 47 % among all the cases of skin and joints simultaneous lesions [1–4].
Along with this,
PsA is diagnosed in 5–13 % patients with early-stage inflammatory joints diseases [2,
It was found out that about 60–70 % of psoriasis cutaneous manifestations precede the arthritis and only in 10–20 % of cases both these psoriasis symptoms develop concurrently.
But for all that the diagnosis is established only after the occurrence of joint damage in order of 20 % of the disease cases [2,
For example in the US population PsA affects an estimated 520,000 patients,
and many of them rate it as a large problem in everyday life.
The prevalence varies wide depending on the extent of skin involvement,
which demonstrates the importance of performing broadly representative studies to measure the prevalence of PsA .
The characteristic feature of PsA is the varying severity articular syndrome,
including acute asymmetrical polyarthritis with individual involvement of the joints of distal upper and lower limbs segments: distal interphalangeal joints (DIPJ),
metatarsophalangeal joints (MTPJ),
I carpometacarpal joints,
and I interphalangeal joints (IFJ),
as well as involvement of three or more axial joints – axial arthritis [1,
The first stage of radiodiagnostics in patients with PsA is remains to be the standard radiography (SR),
which could be supplemented by the polypositional researches or by the digital microfocus radiography with direct multiple images magnification if necessary.
Among leading radiographic signs of the pathology are: dislocations and subluxations,
as well as,
the presence of bone erosions and enthesophytes in the tendons attachments.
SR has not always allows assessment of bone structure changes in patients with PsA [2,
as a result of the development of up-to-date special-purpose cone-beam computed units,
it became possible to examine distal segments of the upper and lower limbs.
Cone-beam computed tomography (CBCT) imaging is based on scanning the region of interest with usage of a pulsed X-ray beam.
It is collimated so that the radiation is structured in the form of a cone.
The tissue-attenuated X-ray radiation then reaches a flat-panel detector.
The use of cone-beam technology means that a single turn of the X-ray tube around the target generates a primary image ready for further post-processing.
Another important advantage of CBCT vs.
multi-slice CT is the potential for a significant reduction in exposure dose,
due to the short duration of direct X-ray irradiation and high sensitivity of the flat-panel detector.
Recent numerous studies have demonstrated that CBCT of distal segments of upper and lower limbs with its high spatial resolution and wide spectrum of images post-processing has a high accuracy,
sensitivity and specificity in the detection of pathological bone structure remodeling.
This affect remains even in cases when its size do not exceed 1–2 mm [10–16].
These capabilities and advantages mean that CBCT provides an expedient alternative to multi-slice CT for the examination of the hands of PsA patients.
The actual literature indicates absence of publications on applicability of CBCT for PsA patients.
Despite the obvious advantages of the technique,
the hand and wrist CBCT opportunities in identification of the leading X-ray signs of PsA main forms are not detected; the pathological changes assessing mechanism of hand and wrist CBCT in patients with PsA,
including dynamic observation is not created; there is no standardized protocol for the description of the results of such examinations.
the role and place of CBCT in the diagnostic algorithm in patients with PsA has not been specified yet.
All these factors have become the basis for performing this study.
Before performing the study the following aims and objectives were formulated:
- to indicate the hand and wrist CBCT opportunities of the leading X-ray signs identification of the PsA main forms;
- to determine CBCT advantages compared to SR in hands and wrist joints studies in patients with PsA;
- to develop a standardized protocol for the hand and wrist CBCT pathological changes description in patients with PsA and unification of the received data;
- to clarify the role and place of the hand and wrist CBCT in the diagnostic algorithm in patients with PsA.