Y HQC VI$T NAM THANG 9 - S6 1/2013 l^e xu'ng: TSVKHK 19,8.10'': gap >20 lan,
Coiiforms 118.5 gap > 1 1 lan.
Nhom thit: E.coll 9,5: gap 3 lan; TSVKHK 1,8.10^: gap 1,8 lan; Coiiforms 75,9: gap 1,5 lan;
CI. Perfringens 155,5: gap 1,5 lan.
I ^ u , qua: Nam moc gap >2 lan ; TSVKHK, Coliform gap >1,2 lan.
Thuy, hai san: Coliform 130 gap >13 lan;
TSVKHK 9,0.10^: gap >9 lan; nam moc 43,5 gap 4,3 lan.
Kem: TSVKHK 4,0.10^ gap >4 lan;
Coiiforms 207,5: gap >2 lan; CI. Perfringens 20:
gap 2 lan.
Nu'dc da: TSVKHK 7,7.10^: gap 1,5 lan;
Coiiforms 121,9: gap 1,2 lan.
TAI LIEU THAM KHAO
1. Ban chi dao li£n nganh ve v^ sinh an toan ttiiTc pham (2007), "Danh gia thu'c hien cong tac t)ao dam an toan tinuc pham giai doan 2001-2006 va cac bien phap trong tam bao dam an toan thUc pham giai doan 2007-2015", Bao cao hgi nghi toan guSc ve cong tac bao dan? ve sinh an toan thut pham, Nha xuat ban Ha Noi, tr. 66-67.
2. Bp Y te (2001), Quyet dinh sd 5432/ 2001/ QD- BYT cua 86 tn/dng Bo Y te ngay 19/12/ 2001 ve viec ban hanh thudng quy ky thuat djnh ti'nh va bin dinh idOng dgc td vi nam Anatoxin trong thdc pham, Ha Npi.
3. B$ Y t6' (2007), Qui dinh gidi h§n toi da 6 nhiem sinh hgc vi hoa hgc trong thut pham. Ban hanh kem theo quyet djnh so 46/2007/QD-BYT cua Bo trudng Bg y te, Ha Noi.
- I r a n Sang (2007), "6 nhiem thUc pham, an toan thu'c pham", Cue An toan ve sinh thuc pham, Nha xuat ban Ha Not, trang 17- 23.
5. Ha Thj Anh Oao, Le Ngpc Bao (2000), "Giao due kien thu'c ket hop huidlng dan thu'c hanh cho ngu'di i^m dich vu va tieu diing ve an uong gop phan nang cao chat IUdng ve sinh thu'c 3n di/dng pho", Tap chiy hoc dUphong, tap X, so 4.
u. Labo phan tich-Khoa sure khoe moi tru'dng (2009), "Chat lUdng nUdc uong dong chai tren d|a ban thanh pho Ho Chi Minh tir nam 2006 den nam 2008", Ky yeu hgi nghi khoa hoc ve smh an toan thdc pham ian thd 5 nam 2009, Bo V te, Nha xuat ban y hoc, tr. 261-264.
7. Nguyin Thj Loan, Nguyen Quoc Tuan (2004),
"Khao sat chat lu'dng nUdc da du'dng pho ve mat vi smh tai cac quan-TP.HCM nSm 2004", Tap chi y hoc thanh phd Ho Chi Minh, so 4, 2006.
DO DO DAY GIAC MAC BANG SIEU AM
T6MTAT
Muc tieu: Danh gia do day giac mac va phan tich m6t so yeu to lien quan den do day giac mac ciia benh nhan kham tai benh vien mat trung u'dng
Phu'dng phap: Do dp day giac mac trung tam tKeophUOng phap sieu am du'dc thUc hien bSng may do do day giac mac (pachymeter) ciia Alcon tren cac benh nhan tuoi tir 18 trd len va khong co benh cap tfnh 6 mat.
Ketqua: Nghien cuU du'dc thUc hien d 274 benh nhan (548 mat), tuoi tir 18 den 79. Do day giac mac trung binh la 0,526 mm ± 0,Q34. Op day giac mac co li^n quan vdi tuoi (tuoi cang cao thi dp day giac mac cang giam) va khuc xa giac mac (dp day giac mac cao
bai hoc YHa Ngi
Phan biin khoa hpc: PGS.TS. Pham Trpng Van
Nguyen Dire Anh
nhat d nhom khuc xa giac mac du'di 44 D va thap nhat is nhom khiic xa giac mac tren 45 D), sU khac biet co y nghia thong ke (p < 0,05). Khong co su" khac biet co y nghia ciia do day giac mac theo gidi, ben mat va dp dai true nhan cau.
ket luan: Do do day giac mac bSng sieu am la mpt kham nghiem can thiet trong nhan khoa. Can thUc hien dung ki thuat de dam bao so do chfnh xac va khong gay anh hu'dng den giac mac.
Tu'khda: Dp day giac mac, do do day giac mac bang sieu am.
S U M M A R Y
CORNEAL THICKNESS MEASUREMENT W I T H ULTRASOUND PACHYMETER Objective: Evaluation of corneal thickness and analysis of the factors related to the corneal thickness of patients seen at the national eye hospital.
Y HOC VigT NAM THANG 9 - S6 1/2013 Methods: Measurement of central corneal
thickness by ultrasound technique with Alcon pachymeter in patients aged from 18 without having acute ocular diseases.
Results: The study was conducted in 274 patients (548 eyes), aged from 18 to 79. The average corneal thickness was 0.034 ± 0.526 mm. Corneal thickness Is associated with age (older patients have reduced corneal thickness) and corneal refractive power (the corneal thickness was highest in corneas of less 44 D and lowest in corneas of above 45 D), the difference is statistically significant (p <0.05). No significant difference of corneal thickness by gender, nght or left eye, and axial length.
Conclusion: Ultrasound measurement of corneal thickness is an essential exploration in in ophthalmology. It is necessary to perform the technique properly to ensure accurate measurements without affecting the cornea.
Keywords: corneal thickness, ultrasound corneal thickness measurement.
I.
DAT VANOE
Do day giac mac la mot yeu to co the thay doi tnang mpt so tinh trang benh ly cua mat, vi the do dp day giac mac co the giup fch cho chan doan va dieu t n . Tren the gldl da co nhieu cong trinh nghien cu'u ve dp day giac mac, trong do co do do day bang phu'dng phap quang hpc va sieu am. O Viet nam, til tru'dc den nay van de dp day giac mac con ft du'dc chu y tren lam sang. Trong nhuTig nam gan day, do do day giac mac da t r d thanh mot kham nghiem khong the thieu du'q(c trong chan doan benh glocom va trong dieu tri phau thuat khuc xa giac mac. Vdi may do do day giac mac dau tien du'dc trang bj d benh vien mat trung u'dng de phuc vu nghien cii'u phau thuat dieu tri rach giac mac hinh nan hoa dieu tri can thi, chung toi nhan thay can m d rpng them doi tu'dng do de danh gia day dii hdn ve do day giac mac tren benh nhan viet nam, giiip cho kham nghiem nay t r d thanh pho bien trong chan doan va dieu tri them mot so benh mSt khac.
II. OOI Tl/QNG VA PHirONG PHAP NGHIEN CLTU 2 . 1 . Tieu chulin lu'a chon benh nhan:
nhu'ng benh nhan tuoi tu" 18 t r d len, den kham tai benh vien mat trung u'dng.
2.2. Tieu chuan loai truT: benh nhan dang cd benh cap tfnh tai mUt, benh nhan khong phoi hdp trong khi kham.
Kham m^t bao g o m : kham sinh hien vl, do khuc xa khach quan va khiic x a g i a c m?c, nhan ap, do dp d^i true nhan cau va dp day giac mac.
Cac b$nh nhan duHc chia theo 3 nhdm tuoi:
du'di 4 1 tuoi, 4 1 den 60 tuoi va tren 60 tuoi.
Khuc xa giac mac du'dc chia thanh 3 nhdm:
du'di 40 D, >40 D den 46 D, va tren 46 D. Dp dai true nhan a u du'dc chia thanh 4 nhdm: du'di 22mm, 22 den 2 4 m m , > 24 den 26mm, tren 26mm. Nhan ap du'dc chia thanh 3 nhdm: du'di 15 den 18mm Hg, 19 den 20mm Hg, 21 den 23mm Hg.
Dung cu do dp day giac mac du'dc sir dung trong nghien ciTu la may do dp day giac mac (pachymeter) ciia Alcon cd nhu'ng dac diem sau:
- Dau do du'dng kinh 1,5 mm va gap goc cho phep de quan sat hdn.
~ Tan so: 20 MHZ.
- Gidi han d o : 0,2 mm - 1,3 m m . - Do chinh xac: ± 5 micron.
- Bd nhd Idn: cho phep IU\J giff tir 1 den 33 so do.
- Cd nhieu che dp do, hien dong thdi so do thi/c te va sd do cai dat theo yeu cau.
2 . 3 . Phu'dng p h a p d o :
Dat benh nhan nam tren ban kham, tra thuoc te tai mat dicain 1 % 2 lan. Yeu cau benh nhan m d to mat, nhin thang phia tren.
Dat dau do tiep tuyen vdi t m n g tam giac mac, khi dau do tiep xiic dung thi se cd mpt tiep bip ngan va so do hien ngay, neu khdng de che dp tu" dpng thi phai an ban dap mdi hien so do.
Neu dau do tiep xuc khdng t o t thi se cd tieng tut keo dai va khong hien so d o . Sau khi do d trung t a m , may se tu" dpng chuyen sang vj t r i do khac.
Do 5 lan d moi mat, in ra ket qua do va chpn so do hdp ly.
Nghien ciTu mo ta va so sanh cat ngang. Sit dung phan mem thong ke Medcalc 12.1 de phan tich ket qua nghien ciTu.
III. K E T Q U A
So benh nhan du'dc kham la 274 ngu'di (548 mat). Tuoi ciia cac benh nhan trong khoang tir 18 den 79. Nhffng benh nhan nay bao gom: mat binh thu'dng, mat can thj, mat due the thiiy tinh tuoi gia. Nhan ap cua ta ca cac benh nhan trong khoang tff 15 den 23 mm Hg. Khuc xa giac mac du'dc chia thanh 3 nhdm: du'di 44 D, 44 D den 45 D, va tren 45 D. Dp dai true nhan cau du'dc chia thanh 4 nhdm: du'di 22 m m , 22 den <24 m m , 24
Y Hpc VIST NAM THANB 9 - s 6 ia013 (35n <26 mm va tren 26 m m . Nhan ap du'dc chia
thanh 3 nhom; 15 den 18 mm Hg, 19 den 20 mm Hg, 21 den 23 mm Hg.
Dp day giac mac trung tam trung binh do dlTcIc ia 0,526 mm ± 0,034. So do nay xap xi ket qua do bang phu'dng phap quang hoc cua nhieu tac gia ishac (Bang 3). Tuy nhien, co s i / ctienh iech kha idn giQ:a so toi da va so toi thieu (0,610 mm so vdi 0,442 mm). Co sU i<hac biet dp day giac mac theo tuoi, d nhom benh nhan du'di 40
tuoi dp day giac mac ia 0,534 ± 0,033 mm, d nhom benh nhan 41 den 60 tuoi dp day giac mac la 0,522 ± 0,027, d nhom benh nhan 61 den 79 tuoi th^ dp day giac mac ia 0,498 ± 0,025. Nhu v$y tuoi cang cao thi dp day giac mac trung binh cang giam, su ichac biet nay co y nghia thong i<e (p < 0,05). 0 6 day giac mac khong khac biet co y nghTa giii'a nam va nD' cung nhiT giii'a mat phai va mat trai (p>0,05). (Bang 1).
gl:Oo day qiac mac the
Tuoi
Gidi Ben mat
1 8 - 4 0 4 1 - 6 0 6 1 - 7 9 Nam
NO- Phai Trai
3 tuoi, qidi, va ben mat.
0 6 day (mm) 0,534 ± 0,033 0,522 ± 0,027 0,498 ± 0,025 0,531 ± 0,031 0,526 ± 0,035 0,533 ± 0,032 0,534 ± 0,031
Sd mat (%) 228 (41,8) 182 (33,2) 138 (25) 256 (46,7) 292 (53,3) 274 (50) 274 (50)
Tonq 548
548 548 L^n quan vdi khuc xa giac mac, kit qua cho
thay do day giac mac cao nhat d nhom benh nhan co khuc xa giac mac dddi 44 D (0,534 ± 0,033 mm), va thap nhat d nhdm khuc xa giac mac tin 45 D (0,498 ± 0,025 mm), sd khac biet cd y nghia thong ki (p < 0,05). Dp day giac mac
khong cd khac biet cd y nghia thong ke (p >
0,05) gida cac nhdm cd do dai true nhan cau khac nhau va cac nhom nhan ap khac nhau (chi nghien cdU d nhutig benh nhan co nhan ap trong gidi han binh thu'dng).
Bang 2:^0 day giac mac theo khiic xa giac mac, true nhan cau, va nhan ap.
Khuc xa giac mac (D)
True nhan cau (mm)
Nhan ap (mm Hg)
40 - <44 4 4 - 4 5
>45 - 47 20 - <22 22 - <24 24 - <26 2 6 - 3 2 1 5 - 18 1 9 - 2 0 2 1 - 2 3
Do day (mm) 0,534 ± 0,033 0,522 ± 0,027 0,498 ± 0,025 0,531 ± 0,031 0,531 ± 0,031 0,531 ± 0,031 0,526 ± 0,035 0,530 ± 0,028 0,536 ± 0,032 0,533 ± 0,034
Sdmat 188 (34,3) 302 (55,1) 58 (10,6) 146 (26,6) 213 (38,9) 125 (22,8) 37 (6,8) 162 (29,6) 211 (38,5) 175 (31,9)
Tonq 548
548
548
iV. BAN LUiikN
Dp day giac mac la mot so do rat gia tr; de giiip cho chan doan va dieu tr; cac benh mat. Dp day giac mac da dffdc nhieu tac gia tren the gldl nghien cu'u, chii yeu bang phu'dng phap quang hpc va ket qua phan Idn cho thay dd glay giac mac trung tam trung binh trong khoang 0,52 den 0,56 mm (Bang 3).
Bang 3: Dp day giac mac trung tam ciia mot sd nghien cffu.
Nam
SantonI
1952
l-avergne & Kelecom Donaldson
So mat
198_
268
Dp day (mm)
0,524 ±0,041 "
0i_5_l±_Q,04
0,522 ± 0,041
Y HOC VI$T NAM THANG 9 - s 6 1/2013 I Martola & Baum
Lowe
! Tomlinson I belmarcell & Colllgnon
Bron et al.
1968 1 1969 I 1972 i 1973 1999 1
209 157 65 30 134
0,523 ± 0^039
0,517 ± p,0_340^552±0,039_
b/56 ± 0,(M5 _ ] 0,548 ± 0 , 0 4 5 _ _ I
l^ot so nghiin cdu cua Giasson va Nissan [2] da so sanh do day giac mac trung tam do bang phudng phap siiu am va do bSng phudng phap quang hpc da cho thay khong cd sd khac biet co y nghia thdng ke giO^ 2 phudng phap do (Bang 4).Bang 4: So sanh do bSnq sieu am va do bSng quang hoc.
Tac gia Sd mSt Quang hpc
(mm)
0,541± 0,029
Sieu am ( m m )
0,524± 0,039
Nghien cffu cua chiing toi sff dung phffdngphap sieu am. Ket qua cho thay dd day giac mac trung tam la 0,526 mm ± 0,034, tffdng uTig vdi ket qua cua cac tac gia khac. Chiing tdi cho rang dii do bang phffdng phap nao thi ket qua do cung phu thupc rat nhieu vao kT thuat do. Trong phffdng phap do bang sieu am, neu ngffdi do khong thanh thao va nhat quan thi ket qua do ciing sai lech dang ke ngay trong ciing mpt thdi diem.
Sff chenh lech dang ke va cd y nghia thong ke giffa so toi da va sd tdi thieu (0,610 mm so vdi 0,442 mm) la mot yeu to dang lu'u y. Ngoai sff lien quan vdi tuo'i (tuoi cang cao thi dd day giac mac cang giam), cdn cd nhiieu yeu to anh hffdng den dp day giac mac nhu' tuoi, yeu t d di truyen, tat kliue xa, dd cong giac mac, sff bien ddi hinh dang nhan cau. Mac dii trong nghien ciru khong thay ro sff chenh lech dp day giac mac lien quan vdi true nhan eau nhffng tren thffc te lam sang, ehiing tdi nhan thay cd nhieu benh nhan cd dp can thi nang thffdng cd dp day giac mac thap. Sir giam do day giac mac nay cd the do bien dang nhan cSu, thanh gian cau bj cang ra cd the khien cho dp day giac mac va ciing mac bi giam di.
Van de lien quan dp day giac mac vdi nhan ap da dffdc mdt so nghien cffu, tuy nhien van cdn cd ket luan chffa thdng nhat. Bron A va cs [2] khdng thay sff khac biet ve dd day giac mac d nhCr'ng benh nhan gidcdm gdc m d va ngffdi binh thffdng, nhffng lai thay d nhffng ngffdi gloedm nhan ap binh thffdng thi dd day giac mac mdng hdn ngffdi binh thffdng hoac ngffdi glocom gdc md. Nghien cffu ciia mpt so tac gia khac [1,3] lai cho thay cd sff khac biet ed y nghTa thong ke ve dp day giac mac d ngu'di glocom va ngu'di binh thu'dng. Nghien cffu ciia chiing tdi cd han che la chi thu'c hien d nhffng benh nhan cd nhan ap trong gidi han binh thffdng (15 mmHg den 23 mm Hg) da cho thay khong cd sff khac biet ed y
nghia thong ke ve d p day giac mac trong nhom benh nhan nghien c i i l j . Chung tdi thay can phai ed nghien cffu them vdi so Iffdng benh nhan nhieu hdn de danh gia day dii hdn ve dp day giac mac d cac nhdm benh nhan cd nhan ap khac nhau hoac nhffng benh nhan dac biet nhff: can thj nang, vien thi, dai thao dffdng, dang dung mdt so thuoc dieu trj benh toan than.
V. KET LUAN
Do dp day giac mac la mdt kham nghiem can thiet de giup cho chan doan va dieu tri trong nhan khoa. Phffdng phap do bang sieu am cho ket qua chinh xac neu thffc hien diing ki thuat.
Dp day giac mac trung tam trung binh la 0,500 den 0,550 m m . Dp day giac mac cd thay doi nhe theo tuoi va dp khuc xa ciia mat.
T A I LIEU T H A M K H A O
1. Agossou K, Saragoussi JJ, Assouline M, et al (1995). Charactenstiques de la topographic comeenne des candidats a la chirurgie de la myopie. J Fr. Ophtalmol., 18: 688-693.
2. Argus WA: Ocular hypertention and central corneal thickness. Ophthalmology 1995; 102:1801- 1802.
3. Bron A, Chapard J , e t al (1999). La mesure de I'epaisseur comeenne est-elle fiable et utile. J Fr.
Ophtalmol., 22, 2: 160-168.
1. Shah S, Chatterjee A, et al (1999). Relationship between comeal thickness and measured intraocular pressure in a general ophthalmology clinic 106: 2154-2160.
5. Rainer G. et a l : Comparison of ultrasound pachymetry and partial coherence interi^rometry in the measument of central corneal thickness. J Cataract Refract Surg 2002; 28:2142-2145 6. Wickham et a l : Central corneal ttiickness: will one
measurement suffice? Ophthalmoloqv 2005;
112:225-228.
