Usefulness of transvaginal ultrasound and hysteroscopy in diagnosing endometrial hyperplasia and endometrial carcinoma

Modern methods enabling evaluation of endometrium in all phases of the menstrual cycle were presented. Transvaginal ultrasound does not give characteristic pictures. The most frequently observed sonographic features in endometrial hyperplasia and endometrial carcinoma were compared. Most frequently, in 29% we observed the thickening of the endometrium. The enlargement of the uterine body was detected in 27%. The dominant feature in endometrial carcinoma was distortion or lack of medium-focus echo-90%. Different echogenicity was observed in 69% of all cases. Application of hysteroscopy enables us to visualize changed endometrium and also to sample focal lesions for histopathological examination. Endometrial carcinoma was detected in all analyzed cases with application of hysteroscopy and ultrasound. Pathological endometrial hyperplasia was diagnosed by ultrasound only in 44% and with application of hysteroscopy in 84% of all material.     

The first three weeks assessed by transvaginal color Doppler

Transvaginal color Doppler has made possible to study ovarian and uterine perfusion in non-pregnant and pregnant patients, thus advancing the understanding of the early human development. RI of follicular blood flow starts decreasing prior to ovulation reaching its nadir at ovulation. It is considered that apart from hormonal factors the angiogenesis is also involved. The mature corpus luteum shows increased blood flow velocity in relation to preovulatory follicle. Comparing RI values of luteal blood flow of normal and ectopic pregnancy no difference was found. But in threatened, incomplete and missed abortions the resistance and pulsatility indices were significantly higher than in normal pregnancy. The follow up of the luteal flow might have a prognostic value in a group of patients with threatened abortion. In women with spontaneous cycles the day preceding the ovulation impedance to uterine flow velocity starts decreasing. Alterations in flow velocity patterns of the radial and spiral arteries in spontaneous ovulatory cycles are paralleling blood flow dynamics of the uterine arteries. In stimulated cycles RI increases the day before ovulation in both the uterine arteries and their branches. It seems that endometrial perfusion presents more accurate noninvasive assay of uterine receptivity than uterine artery perfusion alone. Endometrial receptivity is maximum during the time of peak luteal function during which implantation is most likely to occur. During the pregnancy impedance to blood flow decrease from the main uterine to the spiral arteries as well as with the advancing gestational age. The spiral arteries in pregnancy become the vessels with completely different haemodynamic characteristics in relation to other arteries of uteroplacental circulation. Color Doppler adds new information on perfusion and pathophysiological changes connected with the ectopic trophoblast implantation.     

Fetal intracranial hemorrhage. Imaging by ultrasound and magnetic resonance imaging

OBJECTIVE: To describe the magnetic resonance imaging (MRI) findings associated with fetal intracranial hemorrhage and to compare them with ultrasound findings. STUDY DESIGN: In four pregnancies complicated by fetal intracranial hemorrhage, fetal imaging was carried out using T2-weighted fast spin echo sequences and T1-weighted fast low angle shot imaging sequences and by transabdominal ultrasonography. RESULTS: An antepartum diagnosis of hemorrhage was made by ultrasound in one case and by MRI in two. Retrospectively, the hemorrhagic area could be identified from the MRI images in an additional two cases and from the ultrasound images in one case. In the cases of intraventricular hemorrhage, the MRI signal intensity in the T1-weighted images was increased in the hemorrhagic area as compared to the contralateral ventricle and brain parenchyma. In a case with subdural hemorrhage, T2-weighted MRI signals from the hemorrhagic area changed from low-to high-intensity signals during four weeks of follow-up. Better imaging of the intracranial anatomy was possible by MRI than by transabdominal ultrasonography. CONCLUSION: MRI can be used for imaging and dating fetal intracranial hemorrhages. Variable ultrasound and MRI findings are associated with this complication, depending on the age and location of the hemorrhage.     

A comparative study of velocity measurements in major blood vessels using magnetic resonance imaging and Doppler ultrasound

Velocity measurements in major blood vessels were obtained in studies of volunteers using magnetic resonance imaging (MRI) and compared with Doppler ultrasound (US). The vessels studied were the abdominal aorta, superior mesenteric artery, common carotid artery, superficial femoral artery and middle cerebral artery. Using a paired t-test, no significant difference was found between velocity values estimated by MRI and US (p > 0.08). The relative advantages of each technique in radiological practice are discussed.     

Congenital muscular torticollis: magnetic resonance imaging and ultrasound diagnosis

According to figures published by the College of Health, 34,837 patients were waiting for in-patient plastic surgery treatment nationwide in 1986. By 1989 this number had increased to 40,085--an increase of 15%. Out of this waiting list, nearly 2000 patients were waiting in Manchester in 1990. Increasing public concern over the length of surgical waiting lists forced the Government to allocate extra resources to reduce both waiting lists and waiting times. We have reviewed the extra work done on a waiting list initiative scheme in Manchester in one year, from 1 August 1990 to 31 July 1991. The waiting list was reduced by 932 patients in one year. The attendance rate of the patients for surgery was excellent and the patients in general were very grateful for having had the treatment. The problems associated with setting us such schemes are enormous and are discussed in detail, with alternative suggestions for preventing waiting lists from building up again in future.     

The morphology of articular cartilage assessed by magnetic resonance imaging (MRI). Reproducibility and anatomical correlation

Quantitative assessment of cartilage volume and thickness in a formalin-alcohol fixed specimen of a human patella was conducted with magnetic resonance imaging (MRI), as it is still unclear whether the morphology of normal and damaged cartilage can be accurately demonstrated with this technique. MR imaging was carried out at 1.0 T (section thickness 2 mm, in-plane-resolution 0.39-0.58 mm) with the following pulse sequences: 1) T1-weighted spin-echo, 2) 3D-MPRAGE, 3) 3D-FISP, 4) 3D-MTC-FISP, 5) 3D-DESS, 6) 3D-FLASH. Following imaging, the patella was sectioned perpendicular to the articular surface at intervals of 2 mm with a diamond band-saw. The volume of its cartilage was determined from the anatomical sections and the MR images, using a Vidas IPS 10 image analysing system (Kontron). Measurements were carried out with and without the low-signal layer in the transitional zone between the articular cartilage and the subchondral bone. If the low-signal layer was included, the volume was overestimated with MRI by 16 to 19%. Without the low-signal layer the volumes were less than those determined from the anatomical sections: T1-SE-18.2%, MPRAGE -22.6%, FISP -17.1%, MTC-FISP -9.5%, DESS -9.3% and FLASH -6.1%. The coefficient of variation for a 6-fold determination of the volume amounted to between 6.2% (T1-SE) and 2.6% (FLASH). The FLASH sequence allowed the most valid and reproducible assessment of the cartilage morphology. The remaining difference from the real volume of the cartilage may be due to the fact that the calcified zone of the cartilage is not delineated by MRI.     

Regional myocardial motion and thickening assessed at rest by ECG-gated 99mTc-MIBI emission tomography and by magnetic resonance imaging

We have validated ECG-gated emission tomography using technetium-99m methoxyisobutylisonitrile for the assessment of regional ventricular function by comparing it with cine magnetic resonance imaging (MRI). Gated tomography was performed at rest in 24 patients referred for myocardial perfusion imaging [17 males and seven females with a mean age of 58 years, nine of whom had had a previous myocardial infarction (MI)]. Scores were assigned to each of nine myocardial segments for wall motion and for thickening. Cine MRI was analysed in an identical fashion. Four out of 216 (2%) segments were uninterpretable by gated tomography because of inadequate tracer uptake. In eight patients without coronary artery disease (CAD), wall motion and thickening were normal by both methods. Gated tomography showed abnormal wall motion or thickening in all patients with previous MI and in five of seven patients with CAD but no prior MI. Association between wall motion and thickening was good (rs=0. 86). Overall, there was good agreement between gated tomography and MRI for both wall motion (178/212 segments, kappa=0.66) and wall thickening (184/212 segments, kappa=0.69). In segments with severely reduced perfusion, however, there was poorer agreement (kappa=0.31). Interobserver and intraobserver agreement was high (kappa from 0.61 to 0.78). Thus, in patients investigated for CAD, there is good overall agreement between gated tomography and MRI but the agreement is lower in segments with severe perfusion defects.     

Functionality and connectivity analysis by magnetic resonance imaging

Magnetic resonance (MR is a remarkably versatile technology applicable to various aspects of medical science. Currently, there are three categories of MR techniques available for probing human brain function in detail. The first category comprises the most widely utilized techniques which make use of the metabolic effects of brain activation, represented by BOLD (blood oxygenation level dependent) functional magnetic resonance imaging (fMRI). The second category of techniques deals with apparent diffusion tensor probing the axonal connectivity and is represented by three dimensional anisotropy contrast (3DAC) axonography. The third category of techniques is a biological application of classical nuclear magnetic resonance (NMR) spectroscopy capable of providing biochemical information in vivo and is represented by spectroscopic imaging (SI). As techniques directly applicable to clinical medicine, BOLD fMRI and 3DAC axonography possess the highest potential.     

Regionally specific pattern of neurochemical pathology in schizophrenia as assessed by multislice proton magnetic resonance spectroscopic imaging

OBJECTIVE: Several single-voxel proton magnetic resonance spectroscopy (1H-MRS) studies of patients with schizophrenia have found evidence of reductions of N-acetyl-aspartate (NAA) concentrations in the temporal lobes. Multislice proton magnetic resonance spectroscopy imaging (1H-MRSI) permits simultaneous acquisition and mapping of NAA, choline-containing compounds (CHO), and creatine/phosphocreatine (CRE) signal intensities from multiple whole brain slices consisting of 1.4-ml single-volume elements. We have used 1H-MRSI to assess the regional specificity of previously reported changes of metabolite signal intensities in schizophrenia. Hippocampal volume was also measured to test the relationship between 1H-MRSI findings and tissue volume in this region. METHOD: Ratios of areas under the metabolite peaks of the proton spectra were determined (i.e., NAA/CRE, NAA/CHO, CHO/CRE) for multiple cortical and subcortical regions in 10 inpatients with schizophrenia. RESULTS: Patients showed significant reductions of NAA/CRE and NAA/CHO bilaterally in the hippocampal region and in the dorsolateral prefrontal cortex. There were no significant changes in CHO/CRE or in NAA ratios in any other area sampled. No significant correlation was found between metabolite ratios in the hippocampal region and its volume. CONCLUSIONS: NAA-relative signal intensity reductions in schizophrenia appear to be remarkably localized, involving primarily the hippocampal region and the dorsolateral prefrontal cortex, two regions implicated prominently in the pathophysiology of this disorder.     

Multipolar laminated electromagnet for low-field magnetic resonance imaging and electron paramagnetic resonance imaging

A cylindrical 16-pole electromagnet (EM) for electron paramagnetic resonance imaging (EPRI) and low-field magnetic resonance imaging (MRI) has been designed by means of two-dimensional and three-dimensional (3-D) finite element analysis (FEA). The use of an automatic procedure that combines FEA with a minimization routine allowed the optimization of the design, in order to improve the homogeneity along the axis of the EM. A prototype has been built by using electrical steel sheets that were cut by laser; this solution reduced significantly the manufacturing cost. The EM operates with a maximum flux density, in the bore, of 0.08 T and has a homogeneity along the axis of about 40 parts per million (ppm) in a spherical region 10 cm in diameter. It generates the main field and two of the three field gradients required in the 3-D image reconstruction. Good agreement was found between the results of simulation and the measured values.     

Predictive value of clinical examination, transrectal ultrasound and magnetic resonance imaging prior to radiotherapy in carcinoma of the cervix

The objectives of this study were to compare tumour staging and volume assessment by examination under anaesthesia (EUA), transrectal ultrasound (TRU) and magnetic resonance imaging (MRI) in patients with invasive carcinoma of the cervix, and to correlate findings with long-term outcome following treatment by radiotherapy. Tumour staging was performed on 60 patients immediately before starting radiotherapy. Clinicians and radiologists performing EUA, TRU or MRI were blinded to the results of other investigations. Tumour stage and dimensions were recorded prospectively for each technique, and analysed for concordance. The relationship between pre-treatment stage, size of tumour and patient outcome after radiotherapy was assessed, using clinical status 5 years after treatment as the truth measure. EUA, TRU and MRI assigned the same tumour stage in only 30% of patients and EUA and MRI agreed tumour stage in a further 27%. In cases of disagreement, the MRI stage correlated better with outcome than the TRU or EUA stage. There was a significant difference between tumour volume obtained from measurements made on MRI and those from TRU. 62% of patients with enlarged lymph nodes on pre-treatment MRI either died, or developed tumour recurrence or metastases. The ability of MRI to assess the full extent of bulky tumours and the presence of lymph node enlargement was an advantage over both EUA and TRU in identifying patients with a poor prognosis.     

Preoperative staging of rectal carcinoma by magnetic resonance imaging with a pelvic phased-array coil

BACKGROUND: The use of surface coils for magnetic resonance imaging (MRI) allows enhanced image definition and so potentially more accurate staging of colorectal cancer. Endorectal coil imaging is invasive, operator dependent and impossible in a high proportion of patients due to rectal stricture. The phased-array pelvic coil, however, is non-invasive and applicable to all rectal tumours. METHODS: A pelvic phased-array coil was used for preoperative MRI staging of 38 primary rectal carcinomas. Results were expressed according to the Dukes and tumour nodes metastasis (TNM) classifications. After resection of the tumour, the stage predicted on MRI was compared with the pathological classification. RESULTS: The overall accuracy of preoperative staging with the pelvic phased-array coil was 55 per cent for both Dukes class and T stage. Assessment of nodal involvement gave an overall accuracy for MRI of 76 per cent with a sensitivity of 57 per cent and specificity of 88 per cent. CONCLUSION: Use of a pelvic phased-array coil did not improve the staging accuracy of MRI to a clinically useful level.     

Regression of increased left ventricular masses in elderly hypertensive patients on lisinopril as assessed by magnetic resonance imaging

RATIONALE AND OBJECTIVES: We investigated, using magnetic resonance imaging, whether the addition of lisinopril could reduce increased left ventricular (LV) masses in hypertensive patients whose blood pressure was well controlled with nifedipine. METHODS: Fourteen hypertensive patients being treated with nifedipine and having an interventricular septum thickness of more than 12 mm were studied. Half of them were given 5 mg lisinopril, and the others were not. Short-axis images of the left ventricle from the base to the apex were obtained by a standard spin-echo pulse sequence. The entire LV mass was calculated from the area of short-axis slices of the left ventricle multiplied by slice thickness. RESULTS: Blood pressure fell slightly and almost equally in both groups. The LV mass and LV mass index showed a significant decrease in the lisinopril-treated group but not in the control group. CONCLUSION: Results demonstrate the effectiveness of lisinopril in reducing increased LV masses, at least in combination with nifedipine.     

Post-transplant cerebral toxoplasmosis diagnosed by magnetic resonance imaging

We report on a case of an endogenous frontal sinolith and a literature review of classification and use of the terms rhinolith, and sinolith.     

Cardiac metastatic melanoma investigated by magnetic resonance imaging

A case of tricuspid valve regurgitation due to a non-penetrating chest trauma was presented. This case involves a 20-year-old man, who was admitted to a nearby hospital because of rib fracture, mandibular fracture, and hemorrhage of the left hemopneumothorax, caused by a traffic accident. Palpitation and chest discomfort were observed at admission time, but there was no follow-up. Tricuspid regurgitation was pointed out during surgery for the mandibular fracture, and he continued follow up treatment at an outpatient clinic. However his palpitation and chest discomfort worsened, and he was admitted to our department 8 month after injury. During surgery to repair the tricuspid valve, a papillary muscle rupture, valve cusp laceration, and anulus dilatation were found. We performed a papillary muscle repair (chorda tendineae reconstruction), valve cusp suture, and annuloplasty. Absence of the left pericardium was observed during the operation. We reported valve repair of traumatic tricuspid regurgitation which with papillary muscle rupture. Due to its rarity and the fact that there has been no reported cases of papillary muscle repair for traumatic tricuspid regurgitation in Japan, we used researched information on the subject.     

Asbestos-related pericardial thickening detected by magnetic resonance imaging

Magnetic resonance imaging was performed in four male asbestos workers in whom the chest radiograph revealed pleural but not pulmonary or pericardial disease. Patients underwent thoracic multislice spin echo imaging, with measurement of left and right ventricular volumes at end-diastole and end-systole, and a study of the flow in the superior vena cava as an indirect measure to the filling of the right ventricle. Patients also underwent respiratory function tests and high-resolution computed tomography (HRCT). Magnetic resonance, but not HRCT, showed pericardial thickening in two patients. Magnetic resonance demonstrated reduced diastolic flow in the superior vena cava in one patient, reflecting impaired right ventricular filling. All other magnetic resonance measurements of cardiac function were normal. HRCT demonstrated mild asbestosis in three patients in which neither the chest radiograph nor magnetic resonance showed signs of parenchymal disease, and pericardiac calcification without thickening in one patient. It is concluded that magnetic resonance is superior to HRCT in identifying pericardial thickening, but that HRCT is superior to magnetic resonance in identifying asbestos-related pleural and pulmonary disease.     

Tests for DNA and chromosomal damage induced by nuclear magnetic resonance imaging

Chinese hamster ovary (CHO) cells in culture were exposed in a nuclear magnetic resonance (NMR) imaging apparatus to a strong magnetic field, pulsed field gradients, and radio frequency emissions. No chromosomal aberrations were induced even after an exposure of approximately 14 hours. No sister chromatid exchanges were induced by four-hour exposures to either low (average 7.2 mW) or high (average 61.2 mW) radio frequency power. When HeLa cells were exposed for 16 hours to an average radio frequency power of 61.2 mW, no inhibition of DNA synthesis was detectable. These data indicate that the conditions used for NMR imaging do not cause genetic damage which is detectable by any of these methods.     

The processing of first- and second-order motion in human visual cortex assessed by functional magnetic resonance imaging (fMRI)

We have examined the activity levels produced in various areas of the human occipital cortex in response to various motion stimuli using functional magnetic resonance imaging (fMRI) methods. In addition to standard luminance-defined (first-order) motion, three types of second-order motion were used. The areas examined were the motion area V5 (MT) and the following areas that were delineated using retinotopic mapping procedures: V1, V2, V3, VP, V3A, and a new area that we refer to as V3B. Area V5 is strongly activated by second-order as well as by first-order motion. This activation is highly motion-specific. Areas V1 and V2 give good responses to all motion stimuli, but the activity seems to be related primarily to the local spatial and temporal structure in the image rather than to motion processing. Area V3 and its ventral counterpart VP also respond well to all our stimuli and show a slightly greater degree of motion specificity than do V1 and V2. Unlike V1 and V2, the response in V3 and VP is significantly greater for second-order motion than for first-order motion. This trend is evident, but less marked, in V3A and V3B and absent in V5. The results are consistent with the hypothesis that first-order motion sensitivity arises in V1, that second-order motion is first represented explicitly in V3 and VP, and that V5 (and perhaps also V3A and V3B) is involved in further processing of motion information, including the integration of motion signals of the two types.