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Vincent Y T Cheung

Publications and source records attributed to Vincent Y T Cheung.

8 recordsLinked to original sources
PubMed2005

Sonographic measurement of the lower uterine segment thickness in women with previous caesarean section.

OBJECTIVES: To evaluate the accuracy of prenatal sonography in determining the lower uterine segment (LUS) thickness in women with previous Caesarean section and to assess the usefulness of measuring LUS thickness in predicting the risk of uterine rupture during a trial of vaginal birth. METHODS: Sonographic examination was performed in 102 pregnant women with one or more previous Caesarean sections at between 36 and 38 weeks' gestation to assess the LUS thickness, which was defined as the shortest distance between the urinary bladder wall-myometrium interface and the myometrium/chorioamniotic membrane-amniotic fluid interface. Of the 102 women examined, 91 (89.2%) had transabdominal sonography only, and 11 (10.8%) had both transabdominal and transvaginal examinations. The sonographic measurements were correlated with the delivery outcome and the intraoperative LUS appearance. RESULTS: The mean sonographic LUS thickness was 1.8 mm, standard deviation (SD) 1.1 mm. An intraoperatively diagnosed paper-thin or dehisced LUS, when compared with an LUS of normal thickness, had a significantly smaller sonographic LUS measurement (0.9 mm, SD 0.5 mm, vs. 2.0 mm, SD 0.8 mm, respectively; P < 0.0001). Two women had uterine dehiscence, both of whom had prenatal LUS thickness of < 1 mm. Thirty-two women (31.4%) had a successful vaginal delivery, with a mean LUS thickness of 1.9 mm, SD 1.5 mm; none had clinical uterine rupture. A sonographic LUS thickness of 1.5 mm had a sensitivity of 88.9%, a specificity of 59.5%, a positive predictive value of 32.0%, and a negative predictive value of 96.2% in predicting a paper-thin or dehisced LUS. CONCLUSIONS: Sonography permits accurate assessment of the LUS thickness in women with previous Caesarean section and therefore can potentially be used to predict the risk of uterine rupture during trial of vaginal birth.

Adult↗
PubMed2005

Fallopian tube prolapse after laparoscopic resection of pelvic endometriosis.

BACKGROUND: Fallopian tube prolapse is an unusual but often reported complication after hysterectomy. This problem has not yet been reported in a patient undergoing laparoscopy but not hysterectomy. CASE: Fallopian tube prolapse was diagnosed in a patient after laparoscopic excision of pelvic endometriosis, without hysterectomy. The prolapsed fallopian tube was preserved by laparoscopic retrieval from the vagina and closure of the vaginoperitoneal fistula. CONCLUSION: Laparoscopic surgery, when associated with the creation of a vaginoperitoneal fistula, is a risk factor for fallopian tube prolapse. This problem can be diagnosed and safely managed with a laparoscopic approach.

Adult↗
PubMed2004

Sonographic evaluation of the lower uterine segment in patients with previous cesarean delivery.

OBJECTIVE: To evaluate the appearance of the lower uterine segment (LUS) in pregnant women with previous cesarean delivery and to compare the LUS thickness with that in women with unscarred uteri. METHODS: In a prospective study, sonographic examination was performed on 53 pregnant women with previous cesarean delivery (cesarean group), 40 nulliparas (nullip-control), and 40 women who had 1 or more childbirths with unscarred uteri (multip-control) between 36 and 38 weeks' gestation to assess the appearance and compare the thickness of the LUS. In the cesarean group, the sonographic findings were correlated with the delivery outcome and the intraoperative LUS appearance. RESULTS: In the cesarean group, 44 patients (83.0%) had a normal-appearing LUS indistinguishable from that of control groups; 2 patients (3.8%) had an LUS defect suggestive of dehiscence; and 7 patients (13.2%) had thickened areas of increased echogenicity with or without myometrial thinning. Although the cesarean group had a thinner LUS (1.9 +/- 1.4 mm) when compared with both the nullip-control group (2.3 +/- 1.1 mm; P > .05) and the multip-control group (3.4 +/- 2.2 mm; P < .001), only the latter difference achieved statistical significance. One of the 2 patients who had a sonographically suspected LUS defect had confirmed uterine dehiscence during surgery. An intraoperatively diagnosed paper-thin LUS, when compared with an LUS of normal thickness, had significantly smaller sonographic LUS measurements (1.1 +/- 0.6 versus 2.0 +/- 0.8 mm, respectively; P = .004). CONCLUSIONS: Prior cesarean delivery is associated with a sonographically thinner LUS when compared with those with prior vaginal delivery. Prenatal sonographic examination is potentially capable of diagnosing a uterine defect and determining the degree of LUS thinning in patients with previous cesarean delivery.

Adult↗
PubMed2002

Sonohysterographic appearances of endometrial carcinoma: an in vitro study of uterine specimens.

OBJECTIVE: To determine the sonohysterographic appearances of endometrial carcinoma by sonohysterographic examination of uterine specimens. METHODS: A prospective study of sonohysterographic examination on 30 uteri obtained immediately after hysterectomy from women 30 to 86 years of age, diagnosed preoperatively with endometrial carcinoma. The transducer was applied directly on the serosal surface of the anterior uterine wall for sonographic visualization. Sonographic examination was performed initially to assess the endometrial thickness, followed by infusion of normal saline into the endometrial cavity through a Foley catheter inserted into the cervix and repeat sonographic evaluation to characterize endometrial carcinoma. RESULTS: The mean (+/- SD) endometrial thickness on initial sonographic examination was 11.4 (+/- 6.6) mm. Sonohysterographic examination demonstrated 15 uteri to have large, irregular polyploid masses arising from the endometrium, 6 uteri to have focal endometrial thickening, 4 uteri to contain benign-appearing polyp(s), 2 uteri to contain benign-appearing polyp(s) with focal endometrial thickening, and 3 uteri to have normal endometria. CONCLUSION: The sonohysterographic appearance of endometrial carcinoma is variable. Although the majority of endometrial carcinomas appeared as large, irregular polyploid masses, a completely normal sonohysterographic appearance may occur.

Adult↗
PubMedDate not supplied

Pelvic meningocele can be missed during laparoscopy.

Pelvic meningocele is an uncommon condition and is frequently asymptomatic. The diagnosis easily can be mistaken as ovarian cyst on pelvic sonography. In many reported cases, the diagnosis was made during laparotomy for presumed ovarian cysts. Myelography, computerized tomography (CT), or magnetic resonance imaging (MRI) is useful for definitive diagnosis. A 49-year-old woman, who had a normal diagnostic laparoscopy 3 years prior, was referred for a persistent ovarian cyst. Repeat laparoscopy revealed a retroperitoneal cyst in the left pelvic sidewall. Both ovaries and fallopian tubes were normal. Subsequent CT and MRI were used to diagnose pelvic meningocele. We speculate that pelvic meningoceles can be missed during laparoscopy due to the increased intraperitoneal pressure and the potential reduction in the cerebrospinal fluid pressure at the lumbosacral level.

Diagnostic Errors↗