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NGUYN L - K THUT- TIN B TRIU CHNG HC- NH GI TRONG SIU M Y HC Th.S L TUN LINHB MN CHN ON HNH NHTRNG I HC Y H NI

LCH S SIU M1900: P. Curie (Php) hiu ng p in. 1945: Firestone (M) siu m pht hin cc vt nt trong kim loi. Chin tranh th gii 2: d tu ngm, gi l Sonar.Y hc sau chin tranh: 1950 hi ngh Erlangen (CHLB c) tng kt iu tr bng siu m. 1950: Hi qun M d si mt bng my Sonar.

Sau cc cng trnh v p dng siu m chn on bng cc kiu khc nhau: Siu m kiu ASiu m kiu BSiu m kiu TMSiu m DopplerLCH S SIU M

TNH CHT VT L C BN CA SIU MRadiohng ngoi

TNH CHT VT L C BN CA SIU MTruyn qua ca sng siu m khi tng tc vi mi trng vt cht.Tnh cht b hp th khi truyn qua cc mi trng.Phn xKhc xTn x

TNH CHT VT L C BN CA SIU MTc truyn m Khng kh:350m/s, rt km, phi c mi trng trung gian (du nc) siu m vo c th. Mi trng khc: tt, parafin 1400, nc1500, thp 5000m/s.Mi trng sinh hc: phn mm, m 1400, c 1600, xng 3600 4000m/s.v.v. tc TB trong phn mm 1540m/s. Gip o khong cch trong siu m (thi gian i v v ca chm sng siu m).

TNH CHT VT L C BN CA SIU Mphn x

H s phn x:P1 v P2 l t trng ca 2 mi trngV1 v V2 l tc truyn ca 2 mi trngMi trng cng khc nhau phn x cng nhiu.M m-c R= 0,0007, xng s- no R= 0,36.

TNH CHT VT L C BN CA SIU M

TNH CHT VT L C BN CA SIU MKHC X

Khi chm sng m khng i vung gc vi mt phn cch n s b i hng v tip tc i, l hin tng khc x Lm sng: khi nghi ng phi tng gc qut chm sng ti vung gc vi vt s lm mt hin tng khc x v lm gim nh gi.

TNH CHT VT L C BN CA SIU Mtn x

Mt phn sng siu m i hng, to thnh sng khuych tn theo mi hng hay gi l hin tng tn x. Tn x max khi K cu trc

TNH CHT VT L C BN CA SIU MSuy gim ca chm sng siu m

Truyn qua mi trng vt cht, mt phn sng siu m s b hp thu v bin thnh nhit. Cng siu m ti mt su nht nh:Ix= Io- 2FX Io: Cng chm sng siu m b mt u d. Ix: Cng chm sng siu m su X.: H s hp th ca mi trng.F: Tn s ca chm sng siu m.X: Chiu dy ca m xuyn qua, tnh bng cm.

TNH CHT VT L C BN CA SIU MTn s cng cao hp th cng ln: u d tn s cao khm cc tng nngKhm cc tng su: s dng k thut khuych i b theo chiu su (DGC- depth gain control) hay b theo thi gian (TGC- time gain compensation).Suy gim ca chm sng siu m

NGUYN L CU TO MY V TO NH TRONG SIU Mu dX l tn hiuMn hnhLu gi

NGUYN L CU TO MY V TO NH TRONG SIU Mu dPht sng siu m, ghi sng phn x li (echo)

Nguyn tc: hiu ng p in Piezo electric thun, nghch.Tinh th p in (piezoelectric crystal) bin tn hiu in thnh tn hiu sng v ngc li.

NGUYN L CU TO MY V TO NH TRONG SIU M

NGUYN L CU TO MY V TO NH TRONG SIU Mx l tn hiu v hin th

Xung in qua b x l s c khuch i v x l bin thnh tn hiu in v c hin th ln mn nh tng ng vi cu trc phn x siu m.

NGUYN L CU TO MY V TO NH TRONG SIU M3 cch biu din v tr, tnh cht cu trc phn x:A-modeB-modeM-mode

NGUYN L CU TO MY V TO NH TRONG SIU MSiu m DopplerNguyn l chung: hiu ng Doppler, 1842 Johan Christian Doppler (o). Tn s ca chm siu m phn hi thay i so vi tn s ca chm pht i nu khong cch tng i gia ngun pht v vt thay i: tn s tng nu khong cch gim v ngc li.

NGUYN L CU TO MY V TO NH TRONG SIU M2 kiu siu m Doppler: Doppler lin tcDoppler xung

NGUYN L CU TO MY V TO NH TRONG SIU MDoppler lin tcu d: 2 tinh th gm p in, mt pht lin tc sng siu m, mt thu sng phn hi.u: my n gin, ghi dng chy cao, khng aliasing.Nhc: khng ghi chn lc mt vng, my ghi li tt c cc tn hiu dng chy m chm siu m i qua.

NGUYN L CU TO MY V TO NH TRONG SIU MDoppler xungu d: 1 tinh th gm p in, pht v thu sng siu m ngt qung (xung).V tr, th tch vng ghi tn hiu (ca ghi) Doppler c th thay i. V tr ca ghi Doppler: D. Kch thc ca ghi Doppler: L.

NGUYN L CU TO MY V TO NH TRONG SIU Mf > PRF/2: aliasing, nh ph Doppler b ct ct v c ghi sang pha i din ca ng 0.

f =1/4< PRF/2=1/2

f =1/4> PRF/2=(1/3)/2

NGUYN L CU TO MY V TO NH TRONG SIU Mf > PRF/2: aliasing, nh ph Doppler b ct ct v c ghi sang pha i din ca ng 0.4 bin php trnh aliasing:Chuyn ng 0 xung thp, b cc tn s m.Gim f: gim tn s pht fo, gim Cos (nhng < 600 gim sai s).Gim su (d): p bnh nhn.S dng my c PRF cao.

NGUYN L CU TO MY V TO NH TRONG SIU MTn hiu Doppler (lin tc, xung ) c phn tch di dng m thanh hay dng ph:- m sc v cng m thanh.Ph Doppler: phn tch tn hiu Doppler (f) bng php bin i nhanh ca Fourier (Fast Fourier Transform-FFT).Mu

NGUYN L CU TO MY V TO NH TRONG SIU MSiu m Doppler xung kt hp vi siu m ct lp (h thng Duplex).

NGUYN L CU TO MY V TO NH TRONG SIU MSiu m Doppler mu: p dng nguyn l siu m Doppler xung nhiu ca (multigate pulse Doppler) thu tn hiu Doppler trn mt vng trong mt mt ct. Tn hiu t cc ca ghi Doppler c m ho di dng mu v th hin chng ln nh siu m 2D to thnh Doppler mu cn c gi l bn mu ca dng chy (Color Flow Mapping- CFM)

NGUYN L CU TO MY V TO NH TRONG SIU Mc im siu m Doppler mu:

Cc dng chy v pha u d hay i xa u d c th hin bng mu , xanh. Dng chy tc cng ln mu cng sng.Tc dng chy ln: "aliasing" mu: ch tc qu cao thnh mu i lp, phai nht.Dng ri: khm mu (cc , xanh, vng nm xen ln nhau khng theo trt t no c).

NGUYN L CU TO MY V TO NH TRONG SIU MMy siu m c 3 kiu: hai chiu, hnh Doppler mu v ph Doppler gi l h thng Triplex.

NHNG TIN B TRONG TO NH SIU MSiu m Doppler nng lng :Tn hiu Doppler thp nn n c bin i m ho nng lng. Khng nhn bit c chiu ca dng chy.Ton b lng mch c lp y cc pixel mu do Doppler nng lng c nhy gp 3 ln Doppler mu. Cc mch mu nh cng c thy (cc ng mch lin thu thn).Khng cn "aliasing" mu.

NHNG TIN B TRONG TO NH SIU M

Cc tin b v cu to my: u d phn gii cao, u d bin tn, u d a tm im, u d ni soi, ni lng mch...Cc tin b v mode siu m: harmonic, elastic (ARFI), siu m 3D-4D, th tch khi t ng ABVS.

u d a tn

B dy tinh th gm quyt nh tn s ca u d:tinh th cng mng, bc sng cng ngn, tn s cng ln.Nu tinh th gm dy 1mm: u d c tn s 2 MHzTinh th dy 2mm: u d tn s 4MHz

Ngy nay vi s pht trin ca cng ngh vt liu tng hp, cc u d khng ch c mt tn s m c di t 2 n 8 tn s.Cc tin b v cu to my

Cc tin b v cu to myu d Hi t in t

Hi t ca u d:1. u d khng hi t2. u d hi t c hc xa3. u d hi t c hc gn4. Hi t in t

Cc tin b v cu to my phn gii

Phn gii dc ph thuc vo chiu di bc sng v thi gian pht xung.a) Xung ngn, tn s cao: phn gii tt.b) Xung di tn s thp: phn gii km, khng phn bit c hai im.

Cc tin b v cu to my phn giiCc my thi gian thc c th qut ti 250 ng trn 10cm v cho 30 hnh trong mt giy

Phn gii ngang ph thuc vo chiu rng ca chm sng m1.Trng sng m rng khng c hi t2 v 3. Trng sng m hp c hi t

Siu m ho hp mHarmonicCc tin b v mode siu m

Cc tin b v mode siu m

eSie Touch elasticity imagingVirtual Touch tissue imagingVirtual Touch tissue quantificationTt c cc loi u d:SIU M n hi m:nh gi rn ca tn thngCc tin b v mode siu m

SIU M n hi m:eSie Touch elasticity imagingCc tin b v mode siu m

LongitudinalWave Attenuation(~0.5dB/cm MHz)

Velocity :~1540 m/sIn tissue Displacement induced by acoustic push pulse

Detection pulses track displacement on axis to the push pulse within the ROI

The push/detect sequence is stepped across the ROI

Relative displacement difference locations are mapped to the image

STIFF LESIONSOFT TISSUETRANSDUCERREGION OFINTEREST

Virtual Touch tissue imaging: Di cn gan ca ung th v.* Not commercially available in the USA.

LongitudinalWave Attenuation(~0.5dB/cm MHz)

Velocity :~1540 m/sIn tissue Shear waves induced by a virtual extended shear wave source

Detection pulses track displacement vs. time off axis to the acoustic push pulse

Time to Peak (TTP) is measured along each detection beam and speed is computed

The speed of shear wave propagation is related to tissue stiffness

Shear wave attenuation (Approx 10,000x Longitudinal Attenuation)

VS = 1,14 m/sVS = 3,51 m/sVS = 1,4 m/s

SIU M BA CHIU 3D:CU TO U D HAI CHIU BNH THNG V CC LT CT C X L THNH HNH NH BA CHIU THNG QUA MY VI TNH V PHN MM C BIT TU MI HNGCc tin b v mode siu m

BA CHIU THI GIAN THC HAY SIU M BN CHIU -LIVE 3D HAY 4D

U D NHIU TINH TH XP NGANG HAY CONG V H THNG C HAY IN T QUT T NG BN TRONG U D. CH QUT 3D: TRC TRNG, THAI U D M O S THU C HNH NH A BNH DIN TRN MT LN CT. CH QUT 4D: MY SIU M C PHN MM X L HNH NH TRN MY TNH MNH TO HNH NH THI GIAN THC: TI TO B MT, CH XNG...


*ABVS Automated Breast Volumes SimplifiedCc tin b v mode siu mu d khi siu m v t ng

NHNG TIN B TRONG TO NH SIU MCht I m

NHNG TIN B TRONG TO NH SIU MHnh nh kt hp fusion

TRIU CHNG HC SIU M

NH GI TRN SIU MPhn hi lp li ca chm sng m1.1. Phn hi m gia hai mt phng1.2. Phn hi m bn trong mt cu trc1.3. Phn hi m qua mt phng cong2. Suy gim chm sng siu m 3. Tng cng truyn sng m 4. Khc x chm sng m 5. Chm sng m ph 6. Phn hi m chm7. Thay i tc truyn ca sng siu m8. Hiu ng th tch khi9. Hiu ng hnh i

NH GI TRN SIU MPhn hi m gia hai mt phng

A B Siu m u d phng vng thnh bng, c mt phng phn cch l di cn tng m, pha sau c nhng di tng m gi song song c cng khong cch vi mc tng m km r dn. B: S gii thch phn hi ca chm sng m qua li mt hoc nhiu ln gia mt phng phn cch v b mt u d.

NH GI TRN SIU M

Siu m bng bng u d cong. A: Hnh nhiu phn x do tip xc gia u d vi da khng tt, to nn nhng vt song song mp bn tri hnh nh (mi tn). B: Hnh nhiu phn x ca lp kh trong ng tiu ha (mi tn s1), to nn nhng vt sng pha sau (mi tn t s 2-4).

NH GI TRN SIU MPhn hi m bn trong mt cu trc

A: Siu m u d cong vng y phi, c mt phng phn cch l lp kh tng m, pha sau n c v s nhng vt tng m song song. B: S gii thch phn x ca chm sng m i qua li b mt xa v gn ca lp kh vi mt hoc v s ln ri mi tr v u d, to ra nhng vt sng trn hnh siu m, ging hnh ui sao chi.

NH GI TRN SIU M

A: Siu m ti mt u c tuyn c nhng ht cholesterol nm trong thnh c hnh ui sao chi. B: S gii thch phn x ca sng m di chuyn theo nhiu hng trong tinh th cholesterol sau mi tr v u d, to ra nhng vt sng pha sau.

NH GI TRN SIU MPhn hi m qua mt phng cong

A: Siu m gan thy khi u mu tng m soi gng qua c honh. B: S gii thch hin tng soi gng ny do lch hng ca chm sng phn hi khi ti c honh l mt phng phn cch cong.

NH GI TRN SIU MSuy gim chm sng siu m

A: Siu m si ti mt l hnh m m c bng cn lng. B: S gii thch hnh bng cn hnh nn pha sau ca u d hnh d qut, do cu trc c khng tr cao cn hon ton sng m.

NH GI TRN SIU MTng cng truyn sng m

A: Siu m ti mt, nhu m gan sau ti mt tng sng hn so vi nhu m k bn c cng su. B: S gii thch hnh tng sng pha sau hnh nn ca u d r qut, do chm sng m truyn qua cu trc dch (L) khng b suy gim so vi chm sng m qua t chc k bn.

NH GI TRN SIU M Khc x chm sng m

A: Siu m khi dch (1) trong nhu m gan (2), ngoi thy hnh tng sng pha sau cn thy hnh bng cn b (mi tn). B: S gii thch hin tng ny do lch hng ca chm sng m i qua hai b ca cu trc nang dch trn (L), to vng khng c sng m i qua (c) gii hn pha ngoi ca vng tng sng pha sau (R).

NH GI TRN SIU M Chm sng m ph

A: Siu m ti mt, trong lng vng thp ca ti mt c hnh nhiu gi bn mt do nh ca kh trong ng tiu ha k cn (mi tn vng) c dch chuyn v trong lng ti mt (mi tn trng). B: S gii thch hin tng ny: nh t mt vng cu trc (r) phn hi li t chm sng bn, u d nhn c m vang ny v ghi nhn chng vo chm sng chnh (a), nh vy n to nn hnh gi nm trong chm sng chnh.

NH GI TRN SIU M Phn hi m chm

A B A: Siu m bng quang, trong lng bng quang pha sau thnh trc c nhng im m vang (mi tn) l hnh nhiu nh do sng phn hi chm gy ra, ng thi chng l nguyn nhn lm cho thnh trc ca bng quang km r. B: S gii thch hin tng sng phn hi chm do sng phn hi trn ng i v u d b lch hng vi v s nhng khong cch khc nhau, to nn v s im nh ca mt phng phn cch nm xa hn, v c thy r khi pha sau mt phng phn cch ny l cu trc dch.

NH GI TRN SIU MThay i tc truyn ca sng siu m

Siu m qua vng gan, hnh khi u m tng m, km bng cn m nh pha sau. C honh on tng ng vng bng cn ny nm xa hn so vi on c honh sau nhu m gan bnh thng, to nn hnh t on c honh. Hin tng ny c gii thch do tc truyn sng m trong u m chm hn so vi nhu m gan.

NH GI TRN SIU MHiu ng th tch khi

A: Siu m v, gia nhu m tuyn v tng m c ba khi nang, khi ln nht l hnh rng m dch thun nht, hai khi nh hn k bn dng dch gim m; dch chuyn u d vo chnh gia hai khi nh ny th thy l khi dch rng m. B: S gii thch hin tng khi dch thun nht gim m khi lp ct siu m ln hai cu trc dch v t chc k cn (1), v khi dch ny s l khi rng m tht s nu ct vo chnh gia u d (2).

NH GI TRN SIU MHiu ng hnh i

A: Siu m ct ngang vng thng v, sau gan tri c hnh gi ng mch ch i. B: S gii thch hin tng ny l do chm sng m qua mt phng cong ca b c thng b khc x lch hng ti cu trc ri phn hi v u d, ni suy nh s dch chuyn nh ca cu trc l ng thng trc (ng nt ri); cu trc bn tri l hnh tht.

Xin chn thnh cm n!

*

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