Tìm hiểu mối liên quan giữa bất thường nhiễm sắc thể với tăng khoảng sáng sau gáy ở thai nhi

TCNCYH Phu trwong 74 (3) - 2011

T I M Hieu MOI LIEN QUAN GI&A BAT THU'QNG NHIEM SAC TH^ VQI

TANG KHOANG SANG SAU GAY O THAI NHI

Trin Danh Cu'd'ng^ Bill Hai Nam^

^Trwdng Dai hpc Y Ha Npi, ^Dai hpc Y Thii Nguyen

Nghien ciru nham xic anh ty le bit thudng NST a nhCrng trwdng hpp thai nhi cd tang khoang sing sau giy (KSSG).

Doi tuxyng vi phwang phip: thwc hipn tren 250 thai phu cd thai dwac dp KSSG a tudi thai 11-13 tuin 6 ngiy, xic dmh

la tang KSSG vdi ngwang li 3,0 mm vi dwac tw vin chpe hut nwdc di phan tich NST thai nhi. Kit qua: ty le bit thwdng

NST chung li 32,4% d nhung trwdng hap tang KSSG. Trong dd hdi chwng Down (trisomie 21) chiim 12,4%, hdi chung

Turner (45, X) chiim 12%,, hdi chimg Edwards (trisomie 18) chiem 5,6%, bit thwdng ciu true khic cua NST chiim

1,6%,. hpi chimg Patau (trisomie 13) chiim 0,8%,. Vdi sd do cua KSSG tir 3,0 - 3,9mm thi ty le bit thwdng NST li

10,1%, 4,0- 4,9mm li 29%,, 5,0- 5,9mm la 48%,, > 6mm la 64%,. Kit luin: ting KSSG li diu hieu sieu im cd gii tri

quan trpng de phit hien sdm bit thwdng NST, kheing sing sau giy cing Idn thi ty le dj dang NST cing cao.

Tip khda: bit thu'd'ng nhiim sic thi, ting khoang sang sau gay

I. DAT VAN Oe

Khoang sing sau gay (KSSG) l i khoang djch

nim giu-a to ehu-c phin mim eua cpt sdng v i da

vung giy, cd thi keo dii tCr viing cham cho din

lung cua thai. KSSG l i mdt ciu true ed tinh chit

sinh ly- xuit hien d tat ca cie thai nhi trong khoang

tir 11- 13 tuin 6 ngiy tuoi thai, cd the quan sit

dugc bing sieu i m d tuoi thai niy. Sau tuoi thai

niy viing giy eua thai ed hien tugng to ehu-e hda

lim giam ding k i khoang thua i m vang niy [1,6].

Cie nghien eCru ve khoang sang sau gay d i dugc

tiin hinh trdn thi gidi tCr nhirng nim 80 cua thi ky

trude. Cie nghien cu-u niy thiy ring kich thude

cua KSSG ting cd lien quan rit chat che vdi cie

bit thudng nhiim sic thi eua thai nhit l i trong hdi

ChCrng Down. Sieu i m do KSSG d 11- 13 tuin 6

ngiy l i mdt chf tidu bit budc trong sing Ipc v i

chin dpan cie bit thudng hinh thii cung nhu bit

thudng nhiim sic the cua thai. Ty Id bat thudng

NST trong pham vi tCr 19- 88%), tuang Crng vdi kit

qua do KSSG trong pham vi tCr 2 10mm [6,7]. O

Vidt Nam, sieu i m do KSSG cung d i

dugc thye hien trong mdt vii nim gin diy v i di

dugc khuyin cio lim mdt cich he'thong nhung

chua cd nghien eCru nio v i KSSG, nhit l i d

nhCrng trudng hgp KSSG bdnh ly hay nhu-ng

trudng hgp ting KSSG. Do viy, di tii thye hidn

vdi muc tieu: Xic djnh ty Id bit thudng NST d

nhCrng trudng hgp ting KSSG.

II. D6 I TU'QNG VA PHU'QNG PHAP

1. Ddi tipgng

250 thai phu dugc sieu am thai do KSSG d tuoi

thai 11-14 tuin 6 ngay, cd trj so KSSG tir 3,0 mm

trd len, tu vin chpe hut nude oi phin tich NST vio

tuoi thai 17-18 tuin tai benh vien Phu sin Trung

uang (6/2008-6/2011).

2. Phu-ang phap: Nghien eCru md ta tien cCru

3. Cie chi tieu

Do KSSG: dugc thye hien qua sidu im

dudng bung theo ky thuit eua Nicolaides md ta v i

theo chf so Hermann, su- dung ngudng sing Ipc l i

3,0 mm. NhCrng trudng hgp KSSG dudi 3,0mm

khdng lay vio nhdm nghien eu-u [6,7].

Hinh 1: KSSG binh thu'ang (1,4 mm) Hinh 2: KSSG benh ly hay tang KSSG (5,2 mm)

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