Ectopic pregnancy within a rudimentary horn in a case of unicornuate uterus

We report the MRI features of two cases of unicornuate uterus and occluded rudimentary horn. In one patient pregnancy had occurred in the occluded horn, prompting to urgent resection. The second patient illustrates more conventional findings in occluded rudimentary horn. In both cases MRI was able to correctly characterise the nature of the developmental anomaly. Furthermore, on the basis of signal intensities, differentiation between distended lumen due to blood accumulation and amniotic sac in the case of pregnancy could be made. Because of its high accuracy in determining the type of anomaly present, the lack of ionizing radiation, and the ability to evaluate, with the exception of the fallopian tubes, the entire genitourinary tract, MR imaging is essential and plays a key role in the evaluation of women who are consulting for infertility.     

Successful diagnosis and management of prerupture rudimentary horn pregnancy in the second trimester: a case report

Rudimentary horn pregnancy has concerns due to the high incidence of an extreme risk of a life-threatening rupture. Thus, early diagnosis and management are essential to preserving the patient''s life. We present a successful diagnosis and management of a prerupture rudimentary horn pregnancy in a 24-year-old woman presented with chronic pelvic pain and amenorrhea for the last 3 months. On physical examination, she had a mobile, nontender mass equals 16 weeks of gestation. Transvaginal ultrasound revealed an empty uterus with signs of a decidual reaction and a gestational sac adjacent to the uterus and surrounded by less than a 2 mm-in-thickness muscular wall with a positive fetal heart rate. The gestational age was 16 weeks based on biparietal diameter and femur length. Based on these findings rudimentary horn pregnancy was suspected. Laparotomy was performed, unicornuate uterus with unruptured, left rudimentary horn pregnancy was observed, and the pregnant horn with the ipsilateral tube was excised. To conclude, an empty uterus and extrauterine gestational sac surrounded by a thin muscular wall (<2 mm) on ultrasound should raise the suspicion of rudimentary horn pregnancy.     

New developments in magnetic resonance imaging of the nasopharynx and face

New developments such as three-dimensional imaging and MR angiography have improved MR imaging as compared with other radiologic modalities. In the differential diagnosis of tumors and inflammatory changes in the nasopharynx and face, MR imaging is preferable to CT in most cases. An advantage of gadolinium diethylenetriamine penta-acetic acid-enhanced MR imaging in tumorous lesions is the capability to estimate the degree of vascularization. Three-dimensional imaging can show the topographic relationship of lesions to surrounding tissues precisely, allowing better preoperative treatment planning. MR angiography provides the radiologist and the surgeon with further information concerning vessel anatomy and pathology in the neck. MR angiography can be performed without contrast media using fast low-angle shot and flash image with steady precession techniques. Technical and therapeutic aspects of the management of facial and nasopharyngeal lesions as well as clinical findings and the MR imaging appearance of various lesions are discussed.     

46例脑动静脉畸形的MRI和MRA分析

目的：探讨MRI和MRA检查在脑AVM临床诊断中的价值。方法：46例脑动静脉畸形作了常规MRI和MR血管造影,MRI采用SET1、T2加权成像,MRA采用三维时飞跃法。结果：MRI准确显示了46例AVM的瘤巢,11例可见亚急性出血灶,5例可见含铁血黄素沉积,23例病灶区组织软化或萎缩,4例有占位效应。3D-TOF RMA显示41例AVM供血动脉、23例引流静脉。5例加做增强3D-TOF及6例加做2D-TOF后,引流静脉显示明显改善。结论：MRI和MRA结合应用能对脑血管畸形作出较准确的诊断,为临床治疗提供所需的基本信息并对治疗效果作出客观的评价。     

Osteosarcoma. A new diagnostic approach in presurgical loco-regional staging

The value of Magnetic Resonance (MR) imaging was examined in the anatomical staging of bone osteosarcomas. Eleven patients were studied--8 central and 3 parosteal osteosarcomas. The accuracy of MR imaging was compared to that of plain film, scintigraphy, CT, and angiography. MR imaging was superior to both CT and radionuclide scanning in defining intramedullary extension and in showing skip metastases. Cortical erosion in central osteosarcomas was demonstrated by MR imaging, CT, and plain film; in 1 case of parosteal osteosarcoma MR imaging was superior to CT in showing cortical penetration. In two cases MR imaging did not accurately demonstrate the relationship of the tumor to the major vessels; only angiography showed vascular involvement. MR imaging was useful in delineating extraosseous extension. The importance is stressed of a correct use of MR imaging towards an accurate diagnosis. In fact, intramedullary extension and skip metastases were better demonstrated on T1-weighted images with large fields, while T2-weighted images and small fields were needed for the best overall evaluation of extraosseous involvement. In conclusion, MR imaging should be used for preoperative staging of osteosarcomas in those cases where diagnosis was made on the basis of clinical, radiographic, and bioptic findings.     

Intraventricular meningiomas: MR imaging and MR spectroscopic findings in two cases.

CT, MR imaging, MR spectroscopy, and angiography were performed in two men (ages 21 and 48, respectively) with intraventricular meningioma. In both cases, CT and MR imaging showed large tumors located in the trigone of the right lateral ventricle that enhanced intensely after contrast administration. MR spectroscopy was helpful in supporting a preoperative diagnosis of meningioma in both cases.     

Sonographic findings of early pregnancy in the rudimentary horn of a unicornuate uterus: A two case report

Congenital uterine anomalies have a profound impact on reproductive outcomes. The unicornuate uterus accounts for approximately 20% of all congenital uterine anomalies. Unicornuate uterine anomalies with non-communicating rudimentary horns are at risk of developing ectopic pregnancy in the rudimentary horn. Given increased risked of uterine rupture, rudimentary horn pregnancies pose significant maternal health risks. Understanding the sonographic appearance of early pregnancy within the rudimentary horn of the unicornuate uterine configuration is imperative for appropriate and timely clinical management. We present two cases of pregnancy in the rudimentary horn of a unicornuate uterus diagnosed sonographically in the first trimester.     

Imaging techniques in the preoperative diagnosis of soft tissue tumors. A comparison of MRT, CT, sonography, angiography and conventional x-rays]

In a study on 51 patients with histologically confirmed soft tissue tumors (STT), we retrospectively evaluated the preoperative use of imaging procedures (MRI, CT, ultrasound, angiography, plain film) for identification of tumor size, delineation, and determination of malignancy and tissue type. The findings were correlated with intraoperative findings and histological diagnosis. The overall diagnostic method of choice for preoperative imaging of STT is MRI, followed by CT. Ultrasound, although sensitive, lacks the required specificity. Angiography and plain film can only be used for specific indications, as they generally do not make it possible to stage the tumor. Combining our results with those from the more recent literature, we propose a diagnostic algorithm according to which MRI would generally be performed for preoperative staging of STT. CT and plain film should only be used if bony infiltration is suspected; angiography is indicated for planning intraarterial chemotherapy or embolization or if vascular infiltration is probable.     

Recognition and importance of an infraoptic anterior cerebral artery: case report

Although variations of the anterior cerebral artery (ACA)-anterior communicating artery complex are commonly identified on imaging studies, an infraoptic course of the ACA is exceedingly rare. What is believed to be the first case of an infraoptic course of the ACA discovered with MR angiography and further characterized with conventional angiography is presented. The high prevalence of associated aneurysms and the implications for surgical planning make preoperative recognition of this anomaly critical.     

Pancreatic carcinoma: MR, MR angiography and dynamic helical CT in the evaluation of vascular invasion

OBJECTIVE: To assess the value of MR angiography in combination with contrast-enhanced MR imaging, and to compare MR imaging including MR angiography with dynamic contrast-enhanced dual phase helical CT in the preoperative assessment of vascular invasion in patients with suspected pancreatic carcinoma. METHODS AND MATERIAL: MR imaging only, MR imaging including MR angiography and dynamic contrast-enhanced dual phase helical CT images of 48 patients who were operated due to suspicion of pancreas cancer were correlated with the surgery results in terms of vascular invasion. Pathologic diagnosis were pancreatic adenocarcinoma in 31 patients of which nine had surgically confirmed vascular invasion. Sensitivity, specificity, predictive values (including 95% confidence intervals) and accuracy of MR imaging only, MR imaging including MR angiography and helical CT were calculated. RESULTS: Sensitivity, specificity, positive and negative predictive values and accuracy were 56, 100, 100, 85, 87%; 67, 100, 100, 88, 90% and 67, 100, 100, 88, 90%, respectively, for MR imaging only, MR imaging including MR angiography and helical CT in the adenocarcinoma group. The corresponding figures in the overall study group were 56, 97, 83, 90, 90%; 67, 97, 86, 93, 92% and 67, 97, 86, 93, 92%. Confidence intervals (95%) showed that the differences in the diagnostic efficacy of the techniques were not statistically significant in the overall study group, but the confidence intervals were undefined in the adenocarcinoma group due to the small sample size. CONCLUSION: Diagnostic efficacy of MR imaging when combined with MR angiography is equal to that of dynamic contrast-enhanced dual phase helical CT in the assessment of vascular invasion of pancreatic tumors.     

Right lobe living donor liver transplantation: preoperative evaluation of the donor with MR imaging

OBJECTIVE: The purpose of this study was to report our experience in preoperative evaluation of right hepatic lobe donors with a comprehensive MR examination and to compare abdominal MR images, MR cholangiograms, and MR angiograms with findings at surgery, intraoperative cholangiography, and digital subtraction angiography. MATERIALS AND METHODS: Twenty-eight right hepatic lobe donors underwent preoperative evaluation with MR imaging, MR cholangiography, and MR angiography. Two abdominal radiologists independently and randomly reviewed these studies. Points of assessment included focal and diffuse liver disease, calculation of right lobe volumes, depiction of the biliary tract and ductal anomalies, and depiction of the liver vasculature and vascular anomalies. Comparison was made with intraoperative cholangiograms (n = 20) and digital subtraction angiograms (n = 28). RESULTS: MR imaging revealed and characterized focal liver lesions in eight of 28 patients. Calculated right lobe volumes agreed with surgically determined volumes within 7% for reviewer 1 and within 15% for reviewer 2. Intrahepatic bile ducts were depicted completely with MR cholangiography in 25 of 28 patients and with intraoperative cholangiography in nine of 20 patients. MR cholangiography revealed ductal anomalies in six patients. MR imaging and MR angiography depicted the portal veins more completely than digital subtraction angiography. MR imaging and MR angiography correctly excluded portal venous anomalies in all patients and revealed surgically confirmed accessory hepatic veins in six of 28 patients. Angiographically confirmed arterial anomalies were correctly detected in three of 28 patients by at least one reviewer on MR imaging and MR angiography. CONCLUSION: MR imaging, MR cholangiography, and MR angiography provide a comprehensive, accurate means of evaluating donors for factors that may preclude or complicate right hepatic lobe donation.     

Pulmonary arterial hypertension: diagnosis with fast perfusion MR imaging and high-spatial-resolution MR angiography--preliminary experience

PURPOSE: To determine prospectively the accuracy of a magnetic resonance (MR) perfusion imaging and MR angiography protocol for differentiation of chronic thromboembolic pulmonary arterial hypertension (CTEPH) and primary pulmonary hypertension (PPH) by using parallel acquisition techniques. MATERIALS AND METHODS: The study was approved by the institution's internal review board, and all patients gave written consent prior to participation. A total of 29 patients (16 women; mean age, 54 years +/- 17 [+/- standard deviation]; 13 men; mean age, 57 years +/- 15) with known pulmonary hypertension were examined with a 1.5-T MR imager. MR perfusion imaging (temporal resolution, 1.1 seconds per phase) and MR angiography (matrix, 512; voxel size, 1.0 x 0.7 x 1.6 mm) were performed with parallel acquisition techniques. Dynamic perfusion images and reformatted three-dimensional MR angiograms were analyzed for occlusive and nonocclusive changes of the pulmonary arteries, including perfusion defects, caliber irregularities, and intravascular thrombi. MR perfusion imaging results were compared with those of radionuclide perfusion scintigraphy, and MR angiography results were compared with those of digital subtraction angiography (DSA) and/or contrast material-enhanced multi-detector row computed tomography (CT). Sensitivity, specificity, and diagnostic accuracy of MR perfusion imaging and MR angiography were calculated. Receiver operator characteristic analyses were performed to compare the diagnostic value of MR angiography, MR perfusion imaging, and both modalities combined. For MR angiography and MR perfusion imaging, kappa values were used to assess interobserver agreement. RESULTS: A correct diagnosis was made in 26 (90%) of 29 patients by using this comprehensive MR imaging protocol. Results of MR perfusion imaging demonstrated 79% agreement (ie, identical diagnosis on a per-patient basis) with those of perfusion scintigraphy, and results of MR angiography demonstrated 86% agreement with those of DSA and/or CT angiography. Interobserver agreement was good for both MR perfusion imaging and MR angiography (kappa = 0.63 and 0.70, respectively). CONCLUSION: The combination of fast MR perfusion imaging and high-spatial-resolution MR angiography with parallel acquisition techniques enables the differentiation of PPH from CTEPH with high accuracy.     

Assessment of functional MR imaging in neurosurgical planning.

BACKGROUND AND PURPOSE: Presurgical sensorimotor mapping with functional MR imaging is gaining acceptance in clinical practice; however, to our knowledge, its therapeutic efficacy has not been assessed in a sizable group of patients. Our goal was to identify how preoperative sensorimotor functional studies were used to guide the treatment of neuro-oncologic and epilepsy surgery patients. METHODS: We retrospectively reviewed the medical records of 46 patients who had undergone preoperative sensorimotor functional MR imaging to document how often and in what ways the imaging studies had influenced their management. Clinical management decisions were grouped into three categories: for assessing the feasibility of surgical resection, for surgical planning, and for selecting patients for invasive functional mapping procedures. RESULTS: Functional MR imaging studies successfully identified the functional central sulcus ipsilateral to the abnormality in 32 of the 46 patients, and these 32 patients are the focus of this report. In epilepsy surgery candidates, the functional MR imaging results were used to determine in part the feasibility of a proposed surgical resection in 70% of patients, to aid in surgical planning in 43%, and to select patients for invasive surgical functional mapping in 52%. In tumor patients, the functional MR imaging results were used to determine in part the feasibility of surgical resection in 55%, to aid in surgical planning in 22%, and to select patients for invasive surgical functional mapping in 78%. Overall, functional MR imaging studies were used in one or more of the three clinical decision-making categories in 89% of tumor patients and 91% of epilepsy surgery patients. CONCLUSION: Preoperative functional MR imaging is useful to clinicians at three key stages in the preoperative clinical management paradigm of a substantial percentage of patients who are being considered for resective tumor or epilepsy surgery.     

Imaging of carotid artery stenosis: clinical efficacy and cost-effectiveness.

PURPOSETo determine the most accurate, safe, and cost-effective imaging protocol for selecting patients for carotid endarterectomy.METHODSThe actual costs of carotid angiography, ultrasound, and MR angiography were calculated. The diagnostic accuracy with different confidence levels was assessed for carotid ultrasound and MR angiography in 45 patients. The cost-effectiveness and theoretical impact on patient outcome of hypothetical screening models were compared.RESULTSUltrasound before angiography is more effective and considerably cheaper than performing angiography in all patients presenting with transient ischemic attacks ($25 216 versus $48 708 imaging costs per one prevented stroke). When the more costly MR angiography was used to select patients for angiography the slightly higher diagnostic accuracy did not result in a greater number of prevented strokes. As the only preoperative scrutiny, the combination of ultrasound and MR angiography would have resulted in a greater number of prevented strokes than invasive angiography (27.9 versus 23.3) but at the expense of unnecessary surgery (6.6% of all surgeries).CONCLUSIONSUltrasound followed by confirmatory angiography is a cost-effective way to image patients suspected of carotid artery stenosis. MR angiography may become cost effective and lead to a better final patient outcome only when it can reliably replace invasive angiography as the preoperative examination.     

Living renal donors: optimizing the imaging strategy--decision- and cost-effectiveness analysis

PURPOSE: To determine the most cost-effective strategy for preoperative imaging performed in potential living renal donors. MATERIALS AND METHODS: In a decision-analytic model, the societal cost-effectiveness of digital subtraction angiography (DSA), gadolinium-enhanced magnetic resonance (MR) angiography, contrast material-enhanced spiral computed tomographic (CT) angiography, and combinations of these imaging techniques was evaluated. Outcome measures included lifetime cost, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios. A base-case analysis was performed with a 40-year-old female donor and a 40-year-old female recipient. RESULTS: For the donor, MR angiography (24.05 QALYs and 9,000 dollars) dominated all strategies except for MR angiography with CT angiography, which had an incremental ratio of 245,000 dollars per QALY. For the recipient, DSA and DSA with MR angiography yielded similar results (10.46 QALYs and 179,000 dollars) and dominated all other strategies. When results for donor and recipient were combined, DSA dominated all other strategies (34.51 QALYs and 188,000 dollars). If DSA was associated with a 99% specificity or less for detection of renal disease, MR angiography with CT angiography was superior (34.47 QALYs and 190,000 dollars). CONCLUSION: For preoperative imaging in a potential renal donor, DSA is the most cost-effective strategy if it has a specificity greater than 99% for detection of renal disease; otherwise, MR angiography with CT angiography is the most cost-effective strategy.     

Dural arteriovenous fistulas: evaluation with MR imaging

The preangiographic diagnosis of cerebral dural arteriovenous fistula (DAVF) can be difficult. The magnetic resonance (MR) images of 12 patients with angiographically proved DAVF were evaluated to characterize the appearance of these lesions and to identify those patients at increased risk for complications. Patients with DAVF demonstrating venous occlusive disease are at higher risk for complications from the arterialized collateral venous system. This venous occlusive disease is demonstrated best at arteriography. The MR imaging appearance of dilated cortical veins without a parenchymal nidus is suggestive of a DAVF with veno-occlusive disease. Eight of the 12 patients in our series demonstrated this finding at angiography. Complications, including infarction and hemorrhage, were identified at MR imaging in eight patients with MR imaging evidence of veno-occlusive disease. At angiography 42% of these complications were not apparent. In one patient with a DAVF draining into an unobstructed right sigmoid sinus, results of MR study were normal. Although patients with DAVF without veno-occlusive disease may have normal findings at MR imaging, DAVF associated with veno-occlusive disease and dilated pial venous drainage can be documented on MR images. This subset of DAVF patients, many of whom were identified only at MR imaging, is at higher risk for complications due to veno-occlusive disease. These patients are believed to require more urgent therapy. MR imaging is useful in the pretherapeutic planning for patients with DAVF.     

Diagnosis of liver disease in children: value of MR angiography.

We retrospectively studied the clinical use of MR angiography, a gradient-echo technique susceptible to motion, in the preoperative evaluation of the hepatic vasculature in children with liver disease. Twenty imaging examinations were performed in 18 patients 3 months to 10 years old (mean, 2.3 years). Eleven patients had liver tumors and seven had cirrhosis associated with biliary atresia, cystic fibrosis, and short-bowel syndrome. Respiratory motion artifacts were present in most patients, but all MR angiographic studies were technically adequate. Comparing MR angiograms with spin-echo images, we found that vascular visualization was better with MR angiography in 12 cases (60%), equal in five (25%), and worse in three (15%). In 10 of 20 cases, MR angiography provided additional vascular information not present on spin-echo images. MR angiography is a useful adjunct to spin-echo imaging for assessing hepatic vascular anatomy in children with liver disease.     

Evaluation of congenital diseases of the heart

Three different new developments have taken place in the evaluation of congenital heart diseases. First, in the fetal period, intravaginal echocardiography allows earlier diagnosis of significant cardiac abnormalities that could lead to a wanted termination of pregnancy. Second, in adults and children, MR imaging has become a standard imaging modality in complex congenital heart diseases. Moreover MR imaging has become the best noninvasive imaging method in visualization of the great vessels. Finally, in surgery, the intraoperative epicardial echocardiography could improve operation results in the future (solving the regurgitation problem). Postoperatively, MR imaging has become an important diagnostic tool that helps to reduce repeated catheterization and angiography.     

MR imaging of meniscal bucket-handle tears: a review of signs and their relation to arthroscopic classification

Our objective was to review the MR imaging signs of meniscal bucket-handle tears and assess the relevance of these signs to the arthroscopic classification of displaced meniscal tears. Forty-five menisci in 42 patients who had a diagnosis of bucket-handle tear either on MR imaging or on subsequent arthroscopy (in which Dandy's classification of meniscal tears was used) were retrospectively analyzed for MR imaging findings of double posterior cruciate ligament (PCL), fragment within the intercondylar notch, absent bow tie, flipped meniscus, double-anterior horn, and disproportional posterior horn signs. Arthroscopy, which was considered as the gold standard, revealed 41 bucket-handle tears (either diagnosed or not diagnosed by MR imaging) in 38 patients (33 males, 5 females). There was a stastistically significant male preponderance for the occurrence of meniscal bucket-handle tears. Overall, sensitivity and positive predictive value of MR imaging for the detection of meniscal bucket-handle tears were calculated as 90%. Common MR imaging signs of meniscal bucket-handle tears in arthroscopically proven cases of such tears were the fragment in the notch and absent bow tie signs (98% frequency for each). Double-PCL, flipped meniscus, double-anterior horn, and disproportional posterior horn signs, however, were less common (32, 29, 29, and 27%, respectively). An arthroscopically proven bucket-handle tear was found in all patients who displayed at least three of the six MR imaging signs of meniscal bucket-handle tears. The presence of three or more MR imaging signs of meniscal bucket-handle tears is highly suggestive of this condition. Electronic Publication     

MR angiography as a screening tool for intracranial aneurysms: feasibility, test characteristics, and interobserver agreement

OBJECTIVE: MR angiography may be an appropriate tool to screen for unruptured intracranial aneurysms. Feasibility, test characteristics, and interobserver agreement in evaluation of MR angiograms were assessed by members of the MARS (Magnetic resonance Angiography in Relatives of patients with Subarachnoid hemorrhage) Study Group. SUBJECTS AND METHODS: We screened 626 first-degree relatives of a consecutive series of 193 patients with subarachnoid hemorrhage examined at two institutions. We used MR imaging and MR angiography (three-dimensional time-of-flight imaging at both institutions and additional three-dimensional phase-contrast imaging at one institution). Three observers independently assessed the MR angiograms. Conventional angiography was performed in relatives with possible or definite aneurysms on MR angiography and was considered the standard of reference. RESULTS: Thirty-three aneurysms were found in 25 (4%; 95% confidence interval [CI], 3-6%) of 626 relatives. Thirteen (8%) of 169 relatives who refused screening had MR-related reasons; an additional six persons could not be screened because of contraindications for MR imaging (pregnancy, n = 1; claustrophobia, n = 5). The positive predictive value of MR angiography was 100% (95% CI, 79-100%) for "definite" aneurysms and 58% (95% CI, 28-85%) for "possible" aneurysms. Sensitivity of MR angiography was estimated at 83% (95% CI, 65-94%) and specificity at 97% (95% CI, 94-98%). Interobserver agreement in the evaluation of MR angiograms was poor (kappa < .30), probably because different diagnostic strategies used by individual observers resulted in different use of the assessment category "possible aneurysm." CONCLUSION: MR angiography is a feasible screening tool for detection of intracranial aneurysms. Positive predictive value, sensitivity, and specificity are acceptable when at least two neuroradiologists independently assess MR angiograms.