46 Medical Imaging and Radiotherapy Journal (MIRTJ) 39 (Suppl. 1) Medical Imaging and Radiotherapy Journal (MIRTJ) 39 (Suppl. 1) TOČKOVNA ORIENTACIJA PRI RENTGENSKEM SLIKANJU PRSNIH ORGANOV V POSTERIO-ANTERIORNI PROJEKCIJI ORIENTATION POINTS ON CHEST RADIOGRAMS IN POSTERIOR ANTERIOR PROJECTION Sašo Muc 1, Nejc Mekiš 2, Igor Kocijančič 1 1 Univerzitetni klinični center Ljubljana, Klinični inštitut za radiologijo, Zaloška cesta 7, 1000 Ljubljana, Slovenija / University medical centre Ljubljana, Institute of Radiology, Zaloška cesta 7, 1000 Ljubljana, Slovenia 2 Univerza v Ljubljani, Zdravstvena fakulteta, Oddelek za radiološko tehnologijo, Zdravstvena pot 5, 1000 Ljubljana, Slovenija / University of Ljubljana, Faculty of health sciences, Medical Imaging and Radiotherapy Department, Zdravstvena pot 5, 1000 Ljubljana, Slovenia Korespondenca / Corresponding author: muc.saso@gmail.com Prejeto/Recived: 11. 3. 2022 Sprejeto/Accepted: 6. 4. 2022 IZVLEČEK Uvod: Standardno slikanje prsnih organov je najbolj pogosta preiskava v diagnostični radiologiji. Pri slikanju prsnih organov sevalno obremenimo večje področje človeškega telesa, zato je pomembna natančnost pri nastavljanju v izogib ponavljanju slikanja. Namen: Namen magistrske raziskave je bil izboljšanje postavitev in zaslanjanje rentgenskega snopa s pomočjo orientacijskih točk na telesu. S tem zmanjšamo obsevalno polje in hkrati zmanjšamo število neuspelih rentgenogramov. Metode: V raziskavi smo obravnavali 4 orientacijske točke in 6 tarčnih struktur. Na 2544 rentgenogramih prsnih organov v PA projekciji smo meritve neodvisno opravili trije radiološki inženirji. Beležili smo relativne položaje točk na rentgenogramih, ki smo jih kasneje pretvorili v relativne razdalje med njimi. Razdalje so bile popravljene za oddaljenost 5 cm od detektorja. Rezultati: Relativni položaji točk in velika baza podatkov so nam omogočili širok nabor primerjave ter tudi pozicijo lege individualnih pljuč glede na skelet prsnega koša – to nam omogoča zaslanjanje in centriranje s pomočjo orientacijskih točk. V 95 odstotkih so se pljučni apeksi nahajali 1,2 cm pod trnom C7 in 3,1 cm nad AC sklepoma. Če želimo prikazati celotna pljuča z zadnjimi frenikokostalnimi sinusi, moramo centralni žarek nastaviti 3,5 cm kavdalno od trna Th7 oziroma za 1,1 cm kavdalno od trna Th7, če želimo prikazati pljuča do sprednjih frenikokostalnih sinusov. Širina pljuč skoraj vedno zahteva horizontalno lego slikovnega sprejemnika. Razprava in zaključek: Večina literature omenja center slike pri Th7. Z raziskavo smo dokazali, da je optimalni center nižje. Prav tako smo bolje defi nirali optimalni rob slike oziroma velikost pljuč s pomočjo tipljivih orientacijskih točk. Ključne besede: centriranje, prsni organi, orientacijske točke, Th7. ABSTRACT Introduction: Standard chest imaging is the most common examination in diagnostic radiology. When imaging the thoracic organs, a larger area of the human body is exposed to radiation, so accuracy in adjustment is important to avoid repeating the imaging. Purpose: The purpose of this master's research was to improve the placement and screening of the X-ray beam with the help of orientation points on the body. This reduces the radiation fi eld and at the same time reduces the number of failed radiographs. Methods: In the research, we considered four orientation points and six target structures. Measurements were independently performed by three radiological engineers on 2,544 chest radiographs in the PA projection. We recorded the relative positions of the points on the radiographs, which we later converted into relative distances between those points. The distances were corrected by a distance of 5 cm from the detector. Results: The relative positions of points and a large database provided us a wide range of comparisons, as well as the position of individual lungs relative to the skeleton of the chest. This, in turn, allowed us to screen and centre with the help of orientation points. In 95% of cases, the pulmonary apexes were located 1.2 cm below the C7 mandrel and 3.1 cm above the AC joints. To show the entire lung with the posterior phrenicocostal sinuses, the central beam must be adjusted 3.5 cm caudally from the Th7 mandrel or 1.1 cm caudally from the Th7 mandrel to show the lungs to the anterior phrenicocostal sinuses. The width of the lungs almost always requires the image receiver to be in a horizontal position. Discussion and Conclusion: Most of the literature mentions the image centre at Th7. Through research, we have proven that the optimal centre is lower. We also better defi ned the optimal edge of the image or the size of the lungs with the help of tactile orientation points. Keywords: cantering, thoracic organs, orientation points, Th7. Medical Imaging and Radiotherapy Journal (MIRTJ) 39 (Suppl. 1) 47 Medical Imaging and Radiotherapy Journal (MIRTJ) 39 (Suppl. 1) LITERATURA / REFERENCES Lipovec V (2005). Rentgenske slikovne metode in protokoli. Ljubljana: Univerza v Ljubljani, Visoka šola za zdravstvo, 199–226. Angeline M C (1992). Optimizing radiographic positioning. Henrietta, New York: J. B. Lippincott Company, 179–208. Sutton D (2003). Textbook of radiology and imagin Volume 1. 7th edition. London: Elsevier Science Limited. Gajšek B, Šoba P (2005). Analiza ponovljenih rentgenogramov na radiološkem oddelku centralnega urgentnega bloka Kliničnega centra v Ljubljani. Bilten 22 1/2: 3–25. Kenneth L B (1997). Textbook of radiographic positioning and related anatomy. 4th edition. USA: Mosby, 55–84. Kenneth L B (2014). Textbook of radiographic positioning and related anatomy. 8th edition. USA: Mosby, 70–102. Torsten B M, Emil R (1997). Pocket Atlas of Radiographic Positioning. New York, Stuttgart: Georg Thieme Verlag, 206–208. Philip W B, Eugene D F (2003). Pocket Guide to Radiography,. 5th edition. USA: Mosby. Kathy MQ M (2006). Radiographic Image Analysis,. 2nd edition. USA: Elsevier. 53–61. KC Clark (1973). Positioning in Radiography, Volume One, 9th edition. London, 352–353. Swallow RA, Naylor E et al. (1986). Clark's Positioning in Radiography, 11th edition. Great Britain, 286–289. Philip WB, Eugene D F (1999). Merrill's Atlas of Radiographic Positions and Radiologic Procedures,: Volume One. 9th edition. USA: Mosby, 507–543. Scanlon VC, Anders T. (2011). Essentials of anatomy and physiology. 6th edition. Philadelphia: F.A. Davis. Drake RL, Vogl W, Mitchell AW, Gray H. ( 2010). Gray's anatomy for Students 2nd edition. Philadelphia: Churchill Livingstone/Elsevier. European Commission (2014). Medical Radiation Exposure of the European Population Part 1/2; RADIATION PROTECTION N°180. Dostopno na: http://ddmed.eu/ Dose DataMed II https://ec.europa.eu/energy/sites/ener/fi les/documents/ RP180.pdf <20.6.2017