Development of a Head Scanner for Proton CT.

We describe a new head scanner developed for Proton Computed Tomography (pCT) in support of proton therapy treatment planning, aiming at reconstructing an accurate map of the stopping power (S.P.) in a phantom and, in the future, in patients. The system consists of two silicon telescopes which track the proton before and after the phantom/patient, and an energy detector which measures the residual energy or range of the proton to reconstruct the Water Equivalent Path Length (WEPL) in the phantom. Based on the experience of the existing prototype and extensive Geant4 simulations and CT reconstructions, the new pCT scanner will support clinically useful proton fluxes.

Imaging techniques for fibroid detection.

Ultrasound imaging techniques, both transabdominal and transvaginal, are the most accurate and widely used imaging modalities in the detection and characterization of uterine leiomyomas. The diagnosis of these tumours may be enhanced using ultrasound-guided uterine biopsy and hysterosonography. Magnetic resonance imaging provides accurate imaging information, but its cost and lack of significant superiority over ultrasound have hitherto limited its use. Computerized tomography, plain X-ray, and hysterosalpingography have little to offer in the assessment of fibroids.

Low intraovarian vascular resistance: a marker for severe ovarian hyperstimulation syndrome.

OBJECTIVE: To assess intraovarian blood flow in relation to the severity of ovarian hyperstimulation syndrome (OHSS) after controlled ovarian hyperstimulation. DESIGN: A prospective study. SETTING: Monash IVF, Clayton, Victoria, Australia. PATIENT(S): Thirty patients with OHSS after embryo or gamete transfer who also had sonographic evidence of ascites. MAIN OUTCOME MEASURE(S): The resistance to blood flow within the ovaries of 11 patients with severe OHSS and 19 patients with mild OHSS was measured by using transabdominal ultrasonography with color flow and pulsed Doppler imaging. RESULT(S): The pulsatility index (PI), resistance index (RI), and the S-D ratio, all measures of downstream vascular impedance, were significantly lower in those patients with severe OHSS. In cases with RI < 0.48, more than two thirds of the patients had a pleural effusion, whereas patients with either PI < 0.75 or S-D < 1.92 had pleural effusion in over one half of the cases. It was notable that blood flow velocity did not differ significantly between the two groups despite the changes in vascular impedance. CONCLUSION(S): There appears to be a close correlation between the severity of OHSS and the resistance to blood flow within the stimulated ovaries. Measurement of intraovarian vascular resistance before gamete transfer or ET in patients undergoing controlled ovarian hyperstimulation may help in predicting those patients at particular risk of developing severe OHSS.

The control of ovulation in mothers of dizygotic twins.

Dizygotic twinning is familial, suggesting that there may be an inherited abnormality of the control of ovulation that predisposes to double ovulation and, therefore, dizygotic twins. The present study examines 17 mothers of dizygotic twins (MODZT) and 8 control mothers of singletons by daily blood sampling throughout an entire menstrual cycle. Blood samples were assayed for LH, FSH, estradiol, progesterone, and inhibin. The process of follicular development was followed by transvaginal ultrasound. The pituitary LH response to iv GnRH was also assessed. Three of the 16 MODZT double ovulated during the study compared to none of the 8 control mothers (P < 0.05). The number of small follicles (<6 mm) declined significantly in control women at midcycle, but not in MODZT. There was no significant difference in serum FSH, LH, estradiol, or inhibin levels between the 2 groups at any stage of the menstrual cycle. During the follicular phase, serum progesterone levels were significantly higher in MODZT. The response to GnRH stimulation was not different between MODZT and controls. In conclusion, this study demonstrates an increased tendency to double ovulate in MODZT that may be due to a reduced rate of atresia in advanced follicles. Furthermore, the elevated progesterone levels in MODZT during the follicular phase suggest altered intrafollicular steroidogenesis that is independent of gonadotropins.

Urinary vascular endothelial growth factor concentrations in women undergoing gonadotrophin treatment.

A recently identified cytokine, vascular endothelial growth factor (VEGF, vascular permeability factor) has been implicated in ovarian hyperstimulation syndrome in women undergoing assisted reproduction. We postulate that circulating and urinary VEGF values increase following gonadotrophin stimulation, in parallel with the increased ovarian vascularity. A VEGF radioimmunoassay was developed using iodinated VEGF as tracer, a goat anti-VEGF serum as antiserum and recombinant human VEGF as standard. The specificity of the assay was confirmed by comparing the reverse phase high-performance liquid chromatography (HPLC) pattern of VEGF immunoactivity in urine and urine spiked with recombinant VEGF. Urine was concentrated 5-fold prior to measurement by the radioimmunoassay. VEGF:creatinine ratios in early morning urine samples were used to monitor daily urinary VEGF concentrations based on its high correlation (r = 0.77, P < 0.001) with VEGF concentrations in 24 h urine collections. No diurnal variation in VEGF:creatinine ratios was detected. VEGF:creatinine ratios were determined daily from nine women undergoing gonadotrophin-releasing hormone (GnRH) agonist/gonadotrophin treatment. In a further 16 women, early morning urine samples were collected in the peri-ovulatory period. A significant increase (P < 0.005, n = 25) was observed in VEGF:creatinine ratios following human chorionic gonadotrophin (HCG) administration. VEGF:creatinine ratios correlated poorly (r < 0.34) with plasma oestradiol, follicle number and size. It is concluded that urinary VEGF/creatinine ratios increase following HCG stimulation.

Uterine arteriovenous malformation--a rare cause of uterine haemorrhage.

Uterine arteriovenous malformation (AVM) is a rare cause of massive uterine bleeding, with 70 cases reported in the English literature. Although uterine AVM is a rare cause of menorrhagia or postmenopausal bleeding, it is important to consider in the assessment of a patient with abnormal (especially heavy) uterine bleeding because accurate diagnosis can allow appropriate treatment to be planned and avoid hysterectomy in women who wish to retain their reproductive capacity. Until relatively recently this condition was difficult to diagnose and management almost always required hysterectomy. Special investigations (hysteroscopy, Doppler flow ultrasound and pelvic angiography) are important for diagnosis and assessment. Transcatheter embolization has replaced hysterectomy as the treatment of choice in women who wish to retain their fertility. Curettage may precipitate life-threatening haemorrhage and is therefore contraindicated when uterine AVM is suspected.

The value of vaginal ultrasound in the management of menorrhagia.

Vaginal ultrasonography has been carried out on 97 patients with menorrhagia who were either not responding to or not suitable for drug therapy. Ultrasonography demonstrated normal uteri in 33, benign uterine enlargement in 4, bicornuate uteri in 2, intracavitary polyps or fibromyomas in 9, possible adenomyosis in 13 and intramural or subserous fibromyomas in 36. The ultrasound diagnosis markedly increased the accuracy of clinical diagnosis and assisted in the proper choice of treatment which included the avoidance of surgery and the selection of patients most suited to endometrial resection, intrauterine resection of polyps and fibromyomas, and open or laparoscopic myomectomy and hysterectomy. The routine use of high resolution vaginal ultrasound in the management of menorrhagia is recommended.

Percutaneous ultrasound guided uterine needle biopsy.

OBJECTIVE: To determine the safety, accuracy and usefulness of percutaneous ultrasound guided uterine needle biopsy. SETTING: Transabdominal uterine biopsy was performed with an ultrasound directed biopsy gun. The biopsy was performed as an outpatient procedure under local anaesthesia. MAIN OUTCOME MEASURES: The safety, accuracy and clinical value of the procedure; a comparison of the clinical and ultrasound diagnoses with the biopsy and surgical histological diagnoses; and the effect of the biopsy result on the choice of treatment by the surgeon and patient. RESULTS: There were no complications. Accuracy was validated in all seven patients who subsequently had surgical procedures and more extensive myometrial histological investigation. Biopsy diagnosis improved clinical diagnosis in nine of the ten patients, and altered or assisted in the ultrasound diagnosis in eight of the ten patients. Decisions concerning choice of treatment by the doctor or patient were assisted by the biopsy result in seven patients. CONCLUSION: Percutaneous ultrasound guided uterine needle biopsy is a useful procedure in the diagnosis of myometrial disease.

Ultrasound diagnosis and laparoscopic excision of an interstitial ectopic pregnancy.

Interstitial tubal pregnancy occurs in about 5% of ectopic tubal pregnancies and is associated with an increased risk of severe haemorrhage (1). Diagnosis prior to rupture of the pregnancy into the peritoneal cavity is very important to avoid haemorrhage. Its presence has been considered to be a contraindication to laparoscopic surgery (2), although most ectopic pregnancies can be managed laparoscopically by an experienced endoscopist. We report the diagnosis of an interstitial pregnancy by ultrasound before rupture and treatment by laparoscopic excision of the pregnancy.

Ultrasound-guided embryo transfer: a controlled trial.

Embryo transfer (ET) was performed in 94 patients using transvaginal ultrasound guidance. Pregnancy rates were increased over a control group of 246 patients, although statistical significance was reached only in the subgroup of single ETs. Advantages over the traditional blind technique of ET were observed. Acceptance of the procedure by both clinicians and patients was high.

Acute polyhydramnios in twin pregnancies.

This paper reports the experience with acute polyhydramnios complicating twin pregnancies at the Mercy Maternity Hospital for the 10-year and 2-month period from January, 1979 to February, 1989 during which time there were 13 such cases, an incidence of 1 in 4,044 pregnancies. Acute polyhydramnios complicated 1.7% of all twin pregnancies. The perinatal mortality rate was 88.5% and accounted for 16.7% of the perinatal deaths in twins. No major fetal malformations were found. One case of acute polyhydramnios was successfully managed with ultrasonographically guided serial amniocenteses. The management of this rare condition is considered.

A case of multiple (5) ectopic pregnancies, ultimately resulting in a twin pregnancy after in vitro fertilization and embryo transfer.

The history of a woman with anovulation, tubal disease and 5 ectopic pregnancies is presented. She finally succeeded in having a family by conceiving twins in her eighth attempt at in vitro fertilization.

Cervical incompetence in a pregnancy following a cervical ectopic pregnancy.

A case of cervical incompetence is reported which occurred in a pregnancy which followed soon after treatment of a cervical ectopic pregnancy using a Foley catheter. Very few pregnancies following cervical pregnancy have been reported. Although this isolated case is clouded by other risk factors, cervical incompetence should be considered as a potential complication of such pregnancies.

Cervical pregnancy: hysterectomy avoided with the use of a large Foley catheter balloon.

A case of cervical pregnancy in the late first trimester is reported where hysterectomy was avoided, when it seemed inevitable in the face of heavy uncontrolled haemorrhage. Having read the cases reporting easy control of massive haemorrhage from the expanded cervix in such cases by a Foley catheter, we decided to try this recently reported technique - it was magically effective.