1.Outcome of 1,355 consecutive transabdominal chorionic villus samplings in 1,351 patients.
Kin Tze LAU ; Yeung Tak LEUNG ; Yuen Tak FUNG ; Lin Wai CHAN ; Daljit S SAHOTA ; Ngong Tse LEUNG
Chinese Medical Journal 2005;118(20):1675-1681
BACKGROUNDThe true risk of chronic villus sampling (CVS) is poorly defined. The objective of this study was to review the clinical outcome of transabdominal CVS performed in a university teaching unit, with an emphasis on the complication rate.
METHODSA comprehensive audit database was maintained for 1,351 pregnant women, including 17 sets of twin pregnancies, who had a CVS. Details and outcome of all CVSs made in the unit between May 1996 and May 2004 were reviewed. All CVSs were performed by one of 5 operators using the identical techniques.
RESULTSAll procedures were performed transabdominally. A total of 1,355 CVSs were performed because there were 4 dichorionic twin pregnancies which required 2 punctures. The mean gestation at CVS was (11.8 +/- 0.7) weeks, and 97.3% of the procedures were performed between 11 and 13 completed weeks. The majority (96.2%) required only 1 puncture to achieve correct needle placement. The procedure failed to obtain an adequate sample in 4 subjects (0.30%). A total of 1,351 chromosomal studies were requested and there was 1 case (0.07%) of culture failure. The results of chromosomal studies were available within 14 days in 36.7% of the cases and within 21 days in 94.0%. Overall, 77 chromosomal abnormalities (5.7%) and 5 cases of thalassemia major were detected. Pregnancy outcome was unknown in only 13 singleton subjects (0.96%). In the remaining 1,355 fetuses, there were 76 pregnancy terminations (5.56%), 10 fetal losses with obvious obstetric causes (0.73%), and 21 potentially procedure-related fetal losses (1.54%). In the last group, the majority had one or more co-existing obstetric complications. The background fetal loss rate for pregnancies at similar gestational age in the unit was about 0.8%. Therefore, the procedure-related fetal loss rate was estimated to be at the maximum of 0.74%.
CONCLUSIONSIn experienced hands, first trimester transabdominal CVS is an accurate and safe invasive prenatal diagnostic procedure. It should be one of the treatment options available to pregnant women who require prenatal genetic diagnosis.
Adult ; Chorionic Villi Sampling ; adverse effects ; methods ; Chromosome Aberrations ; Female ; Humans ; Pregnancy ; Pregnancy Outcome
2.Novel and Advanced Ultrasound Techniques for Thyroid Thermal Ablation
Wai-Kin CHAN ; Jui-Hung SUN ; Miaw-Jene LIOU ; Chia-Jung HSU ; Yu-Ling LU ; Wei-Yu CHOU ; Yan-Rong LI ; Feng-Hsuan LIU
Endocrinology and Metabolism 2024;39(1):40-46
Thyroid radiofrequency ablation and microwave ablation are widely adopted minimally invasive treatments for diverse thyroid conditions worldwide. Fundamental skills such as the trans-isthmic approach and the moving shot technique are crucial for performing thyroid ablation, and advanced techniques, including hydrodissection and vascular ablation, improve safety and efficacy and reduce complications. Given the learning curve associated with ultrasound-guided therapeutic procedures, operators need training and experience. While training models exist, limited attention has been given to ultrasound maneuvers in ablation needle manipulation. This article introduces two essential maneuvers, the zigzag moving technique and the alienate maneuver, while also reviewing the latest ultrasound techniques in thyroid ablation, contributing valuable insights into this evolving field.
3.Molecular basis of von Hippel-Lindau syndrome in Chinese patients.
Wai-Kwan SIU ; Ronald Ching-Wan MA ; Ching-Wan LAM ; Chloe Miu MAK ; Yuet-Ping YUEN ; Fai-Man Ivan LO ; Kin-Wah CHAN ; Siu-Fung LAM ; Siu-Cheung LING ; Sui-Fan TONG ; Wing-Yee SO ; Chun-Chung CHOW ; Mary Hoi-Yin TANG ; Wing-Hung TAM ; Albert Yan-Wo CHAN
Chinese Medical Journal 2011;124(2):237-241
BACKGROUNDVon Hippel-Lindau (VHL) syndrome is an autosomal dominant familial cancer syndrome predisposing the affected individuals to multiple tumours in various organs. The genetic basis of VHL in Southern Chinese is largely unknown. In this study, we characterized the mutation spectrum of VHL in nine unrelated Southern Chinese families.
METHODSNine probands with clinical features of VHL, two symptomatic and eight asymptomatic family members were included in this study. Prenatal diagnosis was performed twice for one proband. Two probands had only isolated bilateral phaeochromocytoma. The VHL gene was screened for mutations by polymerase chain reaction, direct sequencing and multiplex ligation-dependent probe amplification (MLPA).
RESULTSThe nine probands and the two symptomatic family members carried heterozygous germline mutations. Eight different VHL mutations were identified in the nine probands. One splicing mutation, NM_000551.2: c.463+1G > T, was novel. The other seven VHL mutations, c.233A > G [p.Asn78Ser], c.239G > T [p.Ser80Ile], c.319C > G [p.Arg107Gly], c.481C > T [p.Arg161X], c.482G > A [p.Arg161Gln], c.499C > T [p.Arg167Trp] and an exon 2 deletion, had been previously reported. Three asymptomatic family members were positive for the mutation and the other five tested negative. In prenatal diagnosis, the fetuses were positive for the mutation.
CONCLUSIONSGenetic analysis could accurately confirm VHL syndrome in patients with isolated tumours such as sporadic phaeochromocytoma or epididymal papillary cystadenoma. Mutation detection in asymptomatic family members allows regular tumour surveillance and early intervention to improve their prognosis. DNA-based diagnosis can have an important impact on clinical management for VHL families.
Asian Continental Ancestry Group ; DNA Mutational Analysis ; Humans ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Von Hippel-Lindau Tumor Suppressor Protein ; genetics ; von Hippel-Lindau Disease ; genetics
4.Evaluation of the relationship between cardiac calcification and cardiovascular disease using the echocardiographic calcium score in patients undergoing peritoneal dialysis: a cross-sectional study.
Ho-Kwan SIN ; Ping-Nam WONG ; Kin-Yee LO ; Man-Wai LO ; Shuk-Fan CHAN ; Kwok-Chi LO ; Yuk-Yi WONG ; Lo-Yi HO ; Wing-Tung KWOK ; Kai-Chun CHAN ; Andrew Kui-Man WONG ; Siu-Ka MAK
Singapore medical journal 2023;64(6):379-384
INTRODUCTION:
An echocardiographic calcium score (ECS) predicts cardiovascular disease (CVD) in the general population. Its utility in peritoneal dialysis (PD) patients is unknown.
METHODS:
This cross-sectional study assessed 125 patients on PD. The ECS (range 0-8) was compared between subjects with CVD and those without.
RESULTS:
Among the subjects, 54 had CVD and 71 did not. Subjects with CVD were older (69 years vs. 56 years, P < 0.001) and had a higher prevalence of diabetes mellitus (DM) (81.5% vs. 45.1%, P < 0.001). They had lower diastolic blood pressure (72 mmHg vs. 81 mmHg, P < 0.001), lower phosphate (1.6 mmol/L vs. 1.9 mmol/L, P = 0.002), albumin (30 g/L vs. 32 g/L, P = 0.001), parathyroid hormone (34.4 pmol/L vs. 55.8 pmol/L, P = 0.002), total cholesterol (4.5 vs. 4.9, P = 0.047), LDL cholesterol (2.4 mmol/L vs. 2.8 mmol/L, P = 0.019) and HDL cholesterol (0.8 mmol/L vs. 1.1 mmol/L, P = 0.002). The ECS was found to be higher in subjects with CVD than in those without (2 vs. 1, P = 0.001). On multivariate analysis, only DM and age were independently associated with CVD.
CONCLUSION
The ECS was significantly higher in PD patients with CVD than in those without, reflecting a higher vascular calcification burden in the former. It is a potentially useful tool to quantify vascular calcification in PD patients.
Humans
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Cardiovascular Diseases/diagnostic imaging*
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Cross-Sectional Studies
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Calcium
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Peritoneal Dialysis/adverse effects*
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Vascular Calcification/epidemiology*
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Echocardiography