NGHIEN ciiu VA TRAO DOI
D ay dugc coi la mot phat minh Ion cua nhan loai noi chung va cua y hgc noi rieng, Ke tir do, tia X da dugc su dyng rong rai trong nhieu ITnh vyc nhung duge irng dung nhieu nhat van la trong ITnh vyc y hgc. Tia X cd khd nang xuyen qua nhieu vat chat (nhu CO the ngudi) nen thudng dugc dimg trong chyp anh y te.
Sir dyng dnh tia X va cac ky thuat khac phoi hgp de chan doan hinh anh phuc -vy dieu tri benh. Ddc biet img dyng tia X de chyp anh nham xac dinh cac benh ve xuong va cd the dd ra cac benh ly d phan mem. Ben canh do, tia X con dugc dimg de khdo sat long nguc, giup chan dodn benh ve phoi nhu viem phdi, ung thu phoi, phii ne phdi,.,, Ung dyng tia X cung cd the phdt bien tac rugt (tac ong thyc quan), tran khi (trong noi tang), tran dich (trong cac khoang byng), Ngoai ra, xa tri bang tia X de dieu tri ung thu dang dugc dp dyng kha pho bien tai Viet Nam va tren the gidi. Day la phuang phap sir dung birc xa ion hoa va tia X mang ndng lugng cao de phd vo cdc te bao ung thu. C) Viet Nam, hau nhu benh vien Idn nhd nao cung CO may X-quang.
Ben canh nhung lgi ich to Idn trong viee khai thac, irng dyng tia X trong y hgc thi cdn phai luu y rdng, trong qua trinh van hanh may X-quang trong chan doan y khoa se tao ra birc
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Phdng Qudn ly KHCN chuyen ngdnh, Sd KH&CN
Tia X (X-ray) hay quang tuyen X hay X quang hay tia Rontgen la mot song dien tir CO bu'O'c song trong khoang 10 nanomet den 100 picomet (tu'c la tan so til' 30 PHz den 3EHz). Ngay 8/11/1895 Wil- helm Conrad Rontgen (1845 - 1923) phat hien ra tia X khi dang lam thi nghiem ve xa tuyen am circ.
xa nguy hiem. Tuy may phat tia thap hon so vdi nguon phdng xa nhung chung anh hudng khong nhd den siic khoe con ngudi, dac biet la cdc doi tugng thuong xuyen tiep xiic. Chi 6 thang sau khi phat hien ra tia X quang, ngudi ta da nhan biet dugc hieu img doe hai cua chiing, birc xa ion hoa co the gay ra tinh trang lao hoa sdm, due thuy tinh the, di tat bao thai, gay dan don d tre em, ung thu da va phoi, v.v.
N8u tiep xiic true tiep, thudng xuyen vdi birc xa nay trong pham vi ban kinh 7 mm ma khong CO yem chi, ghe ngdi an toan va kinh chi bao ve se rat nguy hiem. Chinh vi tia X cd kha nang gay ion hda hoac cac phan img nguy hiem cho con ngudi nen trong chyp anh y te luon phai dieu chinh can than bude song, cudng dp va thdi gian chyp anh de han che den miic thap nhat tac hai cua chiing den siic khde.
Tuy nhien, hien nay van de kiem soat chat che va tuan thu cac nguyen tac ve an todn birc xa tai mot so co so cd sir dung may X-quang van chua dugc thyc hien tot. Mot so phdng chyp X quang chua dam bao theo quy chuan nhu dien tich nhd hon mirc quy dinh, chieu cao tran thap, bo tri chieu ddi va chieu rong phdng khdng phii hgp. Yeu cau kich thude toi thieu phdng chyp cat ldp CT scanner hai chieu la 28m-;
ba chi6u la 40 m^; phdng chup rang la 12 m^; phdng chyp nhii anh la 18 m-. Trong dd chieu rong toi thieu la 4,5m va chieu cao toi thieu la 3m (TCVN6561/1999). Khi diSu kien phong chup kliong dam bao quy each thi cudng dp phdt tia se cao hon nhieu lan so vdi mirc cho phep. Mot so ea sd cdn chua quan tam den trang bi den tin bieu cdnh bao khi may dang boat dong hay nhan vien biic xa chua duoe trane bi
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KHOA HOC & Thong Tin CONG NGHENGHIEN cdu VA TRAO 001
Chuyen gia ATBXdang kiem tra thiet hi X-quang. Anh: Quang Dao dung cu che chdn nhu do chi,
lieu ke ca nhan,... Dieu nay khong chi cd dnh hudng tdi sire khoe cua ngudi van hanh mdy X-quang ma cdn dnh hudng tdi ca nhung ngudi xung quanh, nhat la nhii'ng ngudi tdi kham va dieu tri benh, Ben canh dd.
trinh dp ciia ky thuat vien van hanh thiet bj, the he va trinh dp cdng nghe thiet bi ciia nhd sdn xuat cung quyet djnh den mirc dp lieu chieu tren benh nhan vd Ipt ra ngoai. Can bp y te thudng xuyen tiep xiic vdi tia X neu vugt "lieu gidi ban" thi se gap phdi nhung bieu hien tir viee anh hudng birc xa, co thS bi rdi loai he thdng tieu hda, gidm bach cau, vd sinh, sinh con di dang, ung thu, rung tdc, ndn mira hoac nhe thi mdn cdm dj irng. Thiet bi "lieu kc ca nhdn"
se rat hiiu ich \i chung giup
biet dugc thdng tin ve lieu gidi han doi vdi ca nhan, cdc nhan vien van hanh mdy, Cu mdi 3 thdng cdc nhdn vien van hdnh may phdi giri lieu ke cd nhdn di kiem tra mot lan, Thdng thudng, lieu hieu dyng ddi vdi CO the moi nam khdng clugc vugt qud 20inSv (miliSievert) vd trong nam nam lien tiep khong dugc vugt qua 50mSv, Ngoai viee phdi thudng xuyen kiem tra lieu ke ca nhdn. cdc nhan vien birc xa tia X cdn phdi kiem tra sire khde dinh ky it nhat mpt nam mpt lan.
Ben canh do. khi su dung cdc may X-quang da qua sir dung hoac the he cu thi cdc co sd y te nen can nhac den dp an toan ciia chiing, Tuoi thp trung binh ciia may X-quang la tir 7-10 ndm. Tuv vav. hien nav d nhieu co sd khdm chiia benh
sir dyng mdy x-quang den?,..
nam. May cang cu thi chiim tia X khuech tdn trong khdng khi cang nhieu nen dnh hudng len CO the benh nhan va nhdn vien chyp X - quang cang Idn.
Thyc te cha thay, ngudi benh bi chieu xa X-quang vdi mirc lieu cao thi ngoai nhung trieu chirng bieu hien nhu da neu d tren cdn cd the dan den cdc tdn thuong ve phdng xa, gay ra cdc hieu img mupn vdi hai trang thai la tang xac suat ung thu cho ngud'i bi chieu vd, tang hieu iing di truyen.
That ra, khdng cd "lieu an toan" trong chyp X-ray vdi bat ky ddi tugng nao nen tuan thu cdc quy tdc an toan khi Idm viee la bet sire quan trpng, Mac du, mdy X-quang trong chan doan y khoa la loai thiet bj birc xa mang tinh nguy hiem thap so vdi ngudn phdng xa vi mu'c do dnh hudng chi mang tinh eye bp, nhdt thdi, de dang qudn ly vd khde phyc neu xdy ra sy cd ve thiet bi nhung khong cd nghTa la lieu suat birc xa tir cdc phdng X-quang la khdng nguy hiem. Bdi vi cdc co sd y te cd chup X-quang ciing Id nhiing noi tap trung dong ngudi, ddc biet la nhirng ngudi den de kham chu'a benh - hp la nhung ngudi dang cd sire khde kem.
Do vay. cac phdng X-quang phyc vy cho chuan dodn vd dieu tri benh can phai nghiem tiic tuan thii quy dinh \c an toan bii'c xa./.
Thing Tin
i/ijr\A uxdr s.
