Tracking tumor growth rates in patients with malignant gliomas: a test of two algorithms.
(33/8132)
BACKGROUND AND PURPOSE: Two 3D image analysis algorithms, nearest-neighbor tissue segmentation and surface modeling, were applied separately to serial MR images in patients with glioblastoma multiforme (GBM). Rates of volumetric change were tracked for contrast-enhancing tumor tissue. Our purpose was to compare the two image analysis algorithms in their ability to track tumor volume relative to a manually defined standard of reference. METHODS: Three-dimensional T2-weighted and contrast-enhanced T1-weighted spoiled gradient-echo MR volumes were acquired in 10 patients with GBM. One of two protocols was observed: 1) a nearest-neighbor algorithm, which used manually determined or propagated tags and automatically segmented tissues into specific classes to determine tissue volume; or 2) a surface modeling algorithm, which used operator-defined contrast-enhancing boundaries to convert traced points into a parametric mesh model. Volumes were automatically calculated from the mesh models. Volumes determined by each algorithm were compared with the standard of reference, generated by manual segmentation of contrast-enhancing tissue in each cross section of a scan. RESULTS: Nearest-neighbor algorithm enhancement volumes were highly correlated with manually segmented volumes, as were growth rates, which were measured in terms of halving and doubling times. Enhancement volumes generated by the surface modeling algorithm were also highly correlated with the standard of reference, although growth rates were not. CONCLUSION: The nearest-neighbor tissue segmentation algorithm provides significant power in quantifying tumor volume and in tracking growth rates of contrast-enhancing tissue in patients with GBM. The surface modeling algorithm is able to quantify tumor volume reliably as well. (+info)
Bony orbital development after early enucleation in humans.
(34/8132)
AIM: To analyse the extent of bony orbital volume reduction after enucleation in humans. METHODS: Volumetric studies on bony orbital volumes based on three dimensional reconstructions acquired from high resolution computed tomograph (CT) scans were performed in 29 patients with acquired anophthalmia and four patients before enucleation (controls). Eight patients (follow up 25-52 years) were enucleated in childhood aged between 0.4 and 8 years (group I), 21 in adulthood aged between 15 and 53 years. Fifteen of these patients (group IIa) had long standing anophthalmia (follow up 7-53 years), six patients (group IIb) were enucleated 9 months to 4 years before CT. RESULTS: Bony orbital volumes were reduced in all patients with long standing anophthalmia. The median percentage reduction in enucleated orbits was 7.0% in group I, 3.8% in group IIa, and 1.9% in group IIb. In patients with long standing anophthalmia (I and IIa) the reductions were statistically significantly different (p <0.01) from zero. There was some evidence of a correlation between orbital volume reduction and age at enucleation (rho = 0.36, p = 0.09, Spearman rank correlation coefficient) and a statistically significant correlation between volume reduction and time interval since enucleation (rho = -0.5, p = 0.003). Clinically none of the patients showed significant facial asymmetry. CONCLUSIONS: These data provide strong evidence that enucleation both in children and adults is associated with a reduction of bony orbital volume and that this decrease in volume is associated with increasing time. However, the reduction is smaller than generally assumed and does not cause obvious facial asymmetry. It is more related to the time interval since enucleation than the age at enucleation, which makes a mechanism of volume adaptation more likely than just retardation of growth. (+info)
A quantitative MR measure of the fornix in schizophrenia.
(35/8132)
Some cognitive disturbances accompanying schizophrenia may be due to abnormalities in the thalamus and components of the limbic system. The fornix is an important white-matter relay pathway connecting these structures and is likely to be affected in schizophrenia as well.Magnetic resonance images of the fornix were analyzed in 15 schizophrenic patients and 15 matched comparison group subjects. Fornix volume was compared between the two groups and was also correlated with the volumes of other neuroanatomical structures, as well as with illness presentation, clinical status, and cognitive/psychological measures. There was no significant difference in fornix volume between the two groups. Of note, fornix volume correlated significantly with the volumes of the hippocampus, parahippocampus, and the superior temporal gyrus in the schizophrenic subjects, but not in the controls. Moreover, the correlation between fornix and parahippocampal gyrus volumes differed significantly between the two groups. No association was found between fornix volume and illness presentation or between fornix and cognitive/clinical measures.Results suggest that there are no marked changes in fornix volume in schizophrenia by MRI. The fornix, however, may be part of a network of structures affected in schizophrenia, as indicated by correlated volumetric changes. (+info)
Cumulus assessment by three-dimensional ultrasound for in vitro fertilization.
(36/8132)
OBJECTIVE: To correlate the appearances of intrafollicular cumulus-like structures using three-dimensional (3D) ultrasound technology with the recovery of mature oocytes. MATERIALS AND METHODS: A prospective, observational study using 3D ultrasound examination was performed in 50 women undergoing in vitro fertilization (IVF) after ovarian stimulation. Examination was performed on the day of human chorionic gonadotropin (hCG)-ovulation induction. Estradiol-17-beta (E2) levels were measured on the same day. The ovaries were examined for the presence of cumuli in all follicles greater than 15 mm in diameter. Only cumuli demonstrable in all three planes, or in a computer-animated 3D reconstruction, were recorded as 'visible'. The number, maturity, and fertilization rate of retrieved oocytes were compared with the pre-ovulatory assessment of cumuli by 3D ultrasound. STATISTICS: Correlation coefficients (Pearson) between the variables were calculated and stepwise regression analyses performed. RESULTS: A total of 262 cumuli were visualized within 318 follicles from which 296 mature oocytes were retrieved and 218 fertilized. There was a significant correlation between the number of detected cumuli and the number of retrieved oocytes (r2 = 0.83; P < 0.0001), mature oocytes (r2 = 0.78; P < 0.0001), and the number of the fertilized oocytes (r2 = 0.65; P < 0.0001). There was a marked correlation between E2 and the number of follicles and the number of fertilized oocytes. CONCLUSIONS: Cumulus visualization by 3D ultrasound appears to be an indicator for mature oocytes and successful fertilization. Follicles in which the cumulus cannot be visualized in all three planes are unlikely to contain mature oocytes or oocytes in which fertilization is achieved. (+info)
Prenatal evaluation of cephalopagus conjoined twins by means of three-dimensional ultrasound at 13 weeks of pregnancy.
(37/8132)
Cephalopagus twinning, an extremely rare type of conjoined twins, is characterized by the anterior union of the upper half of the body, with two faces each situated on the opposite side of a conjoined head. The prognosis for cephalopagus twins is extremely poor because surgical separation is not an option. Thus early prenatal diagnosis of cephalopagus twins is important to provide an opportunity for pregnancy termination if desired. However, in many instances, cephalopagus twins are misdiagnosed as a singleton pregnancy because of the extreme degree of fusion which makes accurate demonstration of the abnormalities very difficult. This report presents a case of cephalopagus twins which was confirmed at 13 weeks of gestation using three-dimensional ultrasound. (+info)
Value of the electronic scalpel (cut mode) in the evaluation of the fetal face.
(38/8132)
OBJECTIVES: To evaluate the improvement of image quality and diagnostic value of fetal face examinations using the electric scalpel. METHODS: A total of 232 cases were examined. The fetuses were separated into two groups: Group A, including normal fetuses (n = 152) and Group B, fetuses with facial pathology (n = 80). The fetuses were divided into eight subgroups according to gestational age (9-12 weeks, 13-16 weeks, 17-20 weeks, 21-24 weeks, 25-28 weeks, 29-32 weeks, 33-36 weeks and 37-40 weeks). RESULTS: The number of cutting steps for the improvement of image quality ranged from 1 to 9 (mean value 3) in the group of normal fetuses and from 1 to 10 (mean value 3) in the group of fetuses with facial pathology. In the group of normal fetuses, superior image quality improvement was achieved in 68.4% of cases, moderate improvement in 28.9% and poor improvement in 2.6%. In the group of fetuses with facial pathology, high image quality improvement was obtained in 72.5% of cases, moderate improvement in 25.0% and insufficient improvement in 2.5%. There were no differences among the eight subgroups in the number of steps required relating to gestational age. CONCLUSIONS: The use of the electronic scalpel was associated with diagnostic improvement in 71.1% of cases in the group of normal fetuses, and in 75.0% in the group of fetuses with facial pathology. (+info)
Three-dimensional power Doppler imaging in the assessment of Fallopian tube patency.
(39/8132)
OBJECTIVE: The aim of the study was to evaluate the feasibility of three-dimensional power Doppler imaging (3D-PDI) in the assessment of the patency of the Fallopian tubes during hysterosalpingo-contrast sonography (HyCoSy). METHODS: Women attending the fertility clinic were offered a Fallopian tubal patency test as part of the initial investigation. Hysterosalpingo-contrast sonography using contrast medium Echovist was performed on 67 women. Findings on the two-dimensional (2D) gray-scale scanning and three-dimensional power Doppler imaging were compared. The first technique visualizes positive contrast in the Fallopian tube; the second demonstrates flow of medium through the tube. RESULTS: Contrast medium Echovist produced prominent signals on the 3D-PDI image. Free spill from the fimbrial end of the Fallopian tubes was demonstrated in 114 (91%) tubes using the 3D-PDI technique and in 58 (46%) of tubes using conventional HyCoSy. The mean duration of the imaging procedure was less with 3D-PDI, but the operator time which included postprocedure analysis of the stored information was similar. A significantly lower volume of contrast medium (5.9 +/- 0.6 mL) was used for 3D-PDI in comparison with that (11.2 +/- 1.9 mL) used for conventional 2D HyCoSy. CONCLUSION: Color coded 3D-PDI with surface rendering allowed visualization of the flow of contrast through the entire tubal length and free spill of contrast was clearly identified in the majority of cases. The 3D-PDI method appeared to have advantages over the conventional HyCoSy technique, especially in terms of visualization of spill from the distal end of the tube, which was achieved twice as often with the 3D technique. Although the design of the investigation did not allow the side effects of the two techniques to be compared, the shorter duration of the imaging and lower volume of the contrast medium used suggested that the 3D-PDI technique might have a better side-effect profile. The 3D-PDI technique allowed better storage of the information for re-analysis and archiving than conventional HyCoSy. (+info)
Three-dimensional hysterosalpingo-contrast sonography (3D-HyCoSy) as an outpatient procedure to assess infertile women: a pilot study.
(40/8132)
OBJECTIVES: This study aimed to assess the use of three-dimensional hysterosalpingo-contrast sonography (3D-HyCoSy) as a routine outpatient procedure for evaluating infertile women. METHODS: In 25 unselected infertile patients, tubal patency and uterine cavity were investigated by 3D-HyCoSy with saline as a contrast medium. The efficacy of the procedure was evaluated with X-ray hysterosalpingography (XHSG) as reference. RESULTS: The positive predictive value, negative predictive value, sensitivity, and specificity of predicting tubal patency by 3D-HyCoSy were 100, 33.3, 84.4, and 100%, respectively. The full contour of the uterine cavity was depicted in 96% of cases by 3D-HyCoSy and 64% by XHSG (P < 0.005). The uterine cavity area measured on 3D-HyCoSy correlated well with the volume of contrast medium required on XHSG (r2 = 0.8166). CONCLUSIONS: 3D-HyCoSy provided advantages of better assessment of uterine cavity over XHSG. Compared with conventional XHSG, the efficacy of 3D-HyCoSy to assess tubal patency was acceptable. In addition, the procedure of 3D-HyCoSy appears to be better tolerated, requiring no sedation or anesthesia and a reduced examination time. Thus, 3D-HyCoSy with saline as a contrast medium is feasible and could comprise a routine outpatient procedure in the initial evaluation of infertile women. (+info)