TU' NGHIEN CQU DEN TRIEN KHAI - SAN XUAT
May X quang ky thuat so
va trien vong oho tao tai Viet Nam
PHAM GIA KHOI, CAO VAN DIEM, PHAM MINH QUAN Vien Trang thie't bj va Cdng trinh Y te
Cung vol s^ phat trien cua khoa hoc va cong nghe, cac thiet b| chan doan hinh anh cung dang trai qua nhifng hti6c phat trien khong ngihig. Vai thap ky trvidc, ta't ca cac may X quang deu suf dung cong nghe tiAAig tiT vdi bo phan thu nhan hinh anh la phim. Ngay nay, vdi sti phat trien cue cong nghe so', may X quang so'hoa dang dan thay the'cac may X quang the he cii. Viet Nam cung dat diftfc nhifng ket qua bifdc dau trong viec nghien culU, lam chu cong nghe che tao may X quang ky thuat so'suf dung tam cam bien ban phang.
V
iec chuyen ddi anh chup tren phim sang dang anh ky thuat sd cho phep cac bac si, ky thuat vien xfl ly hinh anh de dang thong qua cac phan mem hd trtf.Viec Iflu trfl anh vdi sd Ifltfng Idn ciing di dang htfn rat nhieu nhd sfl dung cac may chu co d cflng dung Iflpng Idn. May X quang sd ciing giup giam thieu chi phi tieu hao phim va boa chat rfla cua may X quang the he cu. Dong thdi, viec sfl dung cac anh ky thuat sd da keo theo sif ra ddi he thd^ng mang co chflc nang Iflu trfl, xfl ly va truyen hinh anh y te (PACS). He thdng nay tao nen sfl linh dong, thuan tien cho viec chan doan va dieu tri tai cac ctf sd y te.
Ngoai ra, may X quang sd tra anh rat nhanh, chi khoang 5 giay ke tfl khi chum tia X dfltfc phat ra, khong can qua bfldc rfla phim. Dieu nay cung giup cac ky thuat vien va bac si CO the giai quyet nhanh gpn cong viec, tang nang suat lam viec. Cac may X quang sd hien nay bao gdm 3 loai: May X quang CR (Computed Radiography), may X quang sfl dung cam bien CCD va may X quang sfl dung tam cam bien ban phang (Flat panel).
B^nhnhan
May X quang CR da dfltfc sfl dung tfl nam 1983 va hien la may X quang sd^ dfltfc sfl dung nhieu nhat, vdi htfn 10.000 he thdng tren khap the gidi. Cot Idi cua cong nghe nay la tam thu anh. Tam thu anh dfltfc che tao bdi mot loai htfp chat cua bari, halogen cd kha nang Iflu trfl nang Ifltfng tia
X. Khi tien hanh chup X quang cho benh nhan, nang Ifltfng tia X sau khi di qua ctf the benh nhan dfltfc Iflu gifl trong mot tam thu thong qua sfl chuyen mflc nang Ifltfng cua cac electron, tao thanh mot tam "anh an" Sau do, tam thu nay se dfltfc quet bang tia laze de giai phdng nang Ifltfng thu dfltfc tfl tia X. Cac tia sang phat ra tfl qua trtnh giai phdng nang Ifltfng se dfltfc thu nhan, tang sang, chuyen hda ve tin hieu dien, khuech dai va sd hda. Anh sd se hoan chinh sau khoang 30-90 giay. Tam thu anh sau khi dfltfc sfl
Quet laze
Nguon sang Hien thi
dung se dfltfc quet bang ludng sang CO cfldng dp manh, ddng nhat de xoa cac vung bien ddi nang Ifltfng tfl tia X. Sau dd tam thu anh cd the sfl dung lai d cac lan chup tiep theo.
Ltfi the cua may X quang CR so vdi may X quang thfldng la kha nang tai sfl dung tam thu anh va anh thu dfltfc da d dang anh sd. Tuy nhien, chat Iflpng anh cua may X quang CR chfla cao do sfl tan xa cua tia laze trong qua trtnh quet anh.
Khac vdi may X quang CR, may X quang sfl dung cam bidn CCD tSn dung dfltfc sfl phat trien cua cdng
HoatdOng^.. ^. „ „ „ , , K H O A I • So thang 9.2011
TQ NGHIEN CL/U DEN TRIEN KHAI - SAN XUAT
TiaX
nghe anh sd, dfla cac cam bien CCD vao tam thu anh de thu nhan dfl lieu. May X quang sfl dung cam bien CCD cho td^c do ra anh nhanh htfn, khong phai qua bfldc quet laze nhfl mdy X quang CR. Ddi vdi may X quang sfl dung cam bien CCD, tia X sau khi di qua ngfldi benh nhan se qua mot tam chuyen ddi, giup chuyen ddi tia X thanh anh sang thfldng.
Tam chuyen ddi thfldng dflpc lam tfl phosphor, mot sd^ loai dat hiem hoac Csl. Cac tia anh sang thfldng sau khi dflpc dieu chinh bdi cac thau kinh se dfltfc thu nhan bdi cac cam bien CCD, dfltfc chuyen ddi sang dang dien va xfl ly sd^. Tuy nhien, chat Ifltfng anh cua may X quang sfl dung cam bien CCD vSn con nhieu ban che. Nguyen nhan chu yeu cua van de nay la do phan Idn cac tia sang phat ra tfl tam chuyen ddi khong lot dfltfc vao cam bien CCD vi dien tich cam bien nho htfn dang ke so vdi tam chuyen ddi. Dieu nay dan den viec mat dfl lieu chup trong qua trinh tdi tao anh.
Han che tren cua cam bien CCD thuc day cac nha khoa hpc tim kiem phfltfng phap thay the bSng mot loai cam bien khac dii Idn de thu nhan anh tfl tam phat sang. Bang each nay, dfl lieu thu dflpc se dfltfc bao toan, giup cai thien chat Ifldng anh
chup - yeu td quan trpng nhat ddi vdi mot may X quang. Cam bien ban phang "gian tiep" ra ddi vdi muc dich khac phuc ban che tren. Chfl "gian tiep"
d day chi viec chuyen ddi tfl tia X sang tin hieu dien van phai qua mot bfldc trung gian la chuyen ddi thanh anh sang thfldng. Hien nay, da co cam bien ban phang trflc tiep, co kha nang chuyen trflc tiep nang Ifltfng tia X sang tin hieu dien.
Tam cam bien" ban phang dfltfc phu Idp chat co kha nang chuyen ddi tia X thanh anh sang thfldng (phosphor, Csl...) tfltfng tfl nhfl cam bien CCD. Ngay dfldi tam chuyen ddi la ma tran cac cam bien ban phang. Cac cam bien nay la cac transistor TFT/diode quang, thfldng dfltfc che tao bang
Cam bien CCD
silicon v6 dinh hinh. Mdi transistor ddng vai tro la mot cam bien anh sang rieng re, co chflc nang thu
TiaX
Anh sang Tam phosphor
(Csl)
T F T ' / Di^ntii | Diode quang Tu d i ^ lini trd
Chuyen dot gian tiep
nhan anh sang va chuyen nang Ifltfng anh sang phat ra thanh dang dien. He thdng cam bien ban phang gian tiep da giup tang cfldng dang ke chat Ifltfng anh so vdi he thdng sfl dung cam bien CCD. Tuy nhien, he thdng tren van phai chuyen ddi tia X thanh anh sang thfldng. Sfl tan xa cua anh sang thfldng sau khi dfltfc chuyen ddi lam anh hfldng den chat Ifltfng anh.
He thdng cam bien ban phang trflc tiep da khac phuc dfltfc van de neu tren. He thdng nay khong sfl dung phosphor hoac Csl lam moi trfldng trung gian ma thay vao do la mot Idp chat quang dSn, thfldng dfltfc lam bang selen v6 dinh hinh.
Cac hat photon cua tia X sau khi den tam cam bien tfltfng tac vdi Idp chat quang dSn, nang Ifltfng cua chung dfltfc chuyen ddi trflc tiep thanh cac hat dan ma khong can gian tiep thong qua anh sang thfldng. Cac dien tfl mdi sinh ra nay dfltfc dat trong dien trfldng co hfldng cfldng do dien trfldng vuong goc vdi tam cam bien. Dudi anh hfldng cua dien trfldng, cac electron bay ve phia dien cifc va dfltfc tich lai d tu dien lifu trfl. Cac dien tich d tflng pixel nay sau do se dfltfc doc va xfl ly sd de tao anh. Khong bi anh hfldng bdi sfl tan xa anh sang, he thdng cam bien ban phang trflc tiep giup tao anh vdi do net gan nhfl hoan hao.
Do net cua anh con phu thuoc vao kich tbfldc pixel thu nhan anh.
Tfltfng tfl nhfl may anh sd, kich
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Dien arc Selen v6 dvnh hinh Di?ncuc
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IDientu
Chuyen doi true tiep
TFT i - Tu dten Imi tri*
Di
S6 thang 9 . 2 0 1 1 ^ ^ » f y « * * ^ " » 39 rav^Nw
TL/ NGHIEN CL/U DEN TRIEN KHAI - SAN XUAT
tbfldc pixel nho se giup anh cd do min cao. Hien nay, cac tam cam bien ban phang ban tren thi trfldng cd kich tbfldc pixel nhan anh da dat dfltfc mflc 120-140 |xm.
Hien nay, Vien Trang thiet bi va Cong trinh Y te dang thflc hien de tai cap nha nfldc "Nghien cflu thiet ke, che tao may X quang ky thuat sd di dong sfl dung trong y te" va dang trong giai doan hoan thien san pham. Nhom nghien cflu da dfla cdng nghe cam bien ban phang trflc tiep vao san pham may X quang cua de tai (sfl dung tam cam bien FLAATZ 560 cda hang Dr.Tech
Han Qudc). Phan mem tich htfp dfltfc viet tren giao dien tieng Viet va CO day du cac tinh nang xfl ly anh can thiet cho viec chan doan.
Tam ban phang FLAATZ 560 co kich tbfldc diem anh la 139 x 139
|im, dp phan giai 3072 x 2560 pixels.
Dien tich thu nhan anh la 344 x 421 mm. Kich tbfldc nay tfltfng tfl so vdi cac cat set phim cua may X quang the he cu. Trong Ifltfng cua tam la 3,7 kg, tao dieu kien cho cac bac si va ky thuat vien co the linh dong vi tri dat cua tam trong qua trtnh chup.
He thdng dieu khien cung vdi cac chi tiet, vd may dfltfc che tao hoan toan tai Viet Nam, co kha nang tich
htfp vdi tam cam bien ban phang FLAATZ 560.
Toan bo he thd^ng dfltfc dieu khien bdi bo dieu khien trung tam MaxxControl MC-300 vdi vi xfl ly la Core™ 2 Duo Mobile T7400 2.16 GHz. Bo dieu khien sfl dung firmware chuyen dung de dieu khien boat dong cua toan bp he thong, dung he dieu hanh thdi gian thflc RTOS Real time Operating System (Windows XP embeded).
Phan mem xfl ly anh bao gdm nhieu module tich htfp: Cac module doc anh va xfl ly anh, module dieu khien boat ddng cua he thdng, module do Ifldng va dieu khien Bo
truyen dfl lieu tdi he thdng chan doan hinh anh khac. Cac module phan mem tren dam bao cho qua trinh boat ddng, ddng bp tin hieu va thao tac xfl ly hinh anh.
May X quang cua de tai sfl dung man hinh cam flng TFT 17"'de hien thi anh chup, hien thi trang thai cua may. Ddng thdi, tren man hinh con cd cac phim bam de thao tac dieu khien may trong qua trinh boat ddng. thiet bi nay nd^i vdi bo dieu khien qua cap chuyen dung vdi chuan LVDS.
Thdng so cua may X quang do Vien che tao nhfl sau:
Cong nghe p h a t tia Cong suat
Bong X quang D a i k V Cac mile mA Dai mAs
Dai thcji gian chup Yeu cau nguon dien chinh
P h a t cao t a n
> 3 0 k W
Anode quay, 2 tieu diem: 0,3/1,0 m m 40-125 kVp, dieu chinh 1 kVp 10-300 mA trong 14 mflc 0,5-500 mAs
1 ms - 10 s
230 VAC, 50 Hz, 13 A, 1 pha, dong xung < 100 A
tao tin hieu cao ap, module bao ve dam bao boat ddng an toan cua may, nhat la cac qua trinh lien quan den cao ap, qua trinh interlock khi may hoat dong, module giao tiep
Sau khi dflpc kiem dinh cac chi tieu, thdng sd ky thuat, san pham may X quang ky thuat sd do Vien che tao se dfltfc thfl nghiem tren dong vat, tien tdi thfl nghiem lam sang tren ngfldi. Viec che tao thanh cdng may X quang ky thuat sd the he mdi nhat vdi ty le noi dia hoa tren 40%, gia thanh canh tranh vdi san pham ngoai nhap se giup chiing ta chu dong trong viec cung cap cac thiet hi ky thuat cao, mdi, nang cao chat Ifltfng kham va dieu tri benh cho nhan dan •
Tdm cam biin bdn phdng vd md hinh mdy X quang cda de tdi
40 K H a A H o " c ^ ° * ^ ^ " 9 9 20ii
