Are prominent medullary veins better than prominent cortical veins as predictors of early clinical outcome in patients with acute ischemic stroke?

PURPOSEThe prominent vessel sign (PVS) on susceptibility-weighted imaging (SWI) can be dichotomized into prominent cortical veins (PCV) and prominent medullary veins (PMV). This study was designed to compare the predictive value of PCV and PMV in the evaluation of the severity of acute ischemic stroke (AIS) in patients within the reperfusion window.METHODSForty-seven consecutive patients with AIS within the middle cerebral artery territory were recruited. Magnetic resonance imaging was performed within 8 hours of symptom onset and at 7 days after stroke onset. Infarct volume was measured, and the early clinical outcome at 7 days was assessed using the modified Rankin Scale. PVS was dichotomized into cases with both PCV and PMV and cases with only PCV according to location.RESULTSPatients with both PCV and PMV (n=32) had higher admission National Institutes of Health Stroke Scale scores (p = 0.020), larger infarct volumes at baseline (p = 0.026) and 7 days (p = 0.007), and larger infarct growth at 7 days (p = 0.050) than those with PCV only. Multivariate regression analysis showed that both the time of onset at baseline (p = 0.013) and infarct growth at 7 days (p = 0.014) could independently predict poor early clinical outcome.CONCLUSIONPMV may predict poor early clinical outcome in AIS patients, and reperfusion therapy may, therefore, be required more urgently in patients with PMV.

Susceptibility-weighted imaging (SWI) is increasingly used in the assessment of ischemic stroke (1) because of the differences in magnetic susceptibility among various components such as blood and blood products (2). The prominent vessel sign (PVS) on SWI sequences has been correlated with the amount of deoxyhemoglobin in the cerebral venous compartments secondary to an increased oxygen extraction fraction in the ischemic tissue (3). It has been reported that patients with PVS have larger infarct volumes and worse clinical outcomes when compared with those without PVS (4). Although the PVS has been reported in patients with ischemic stroke beyond the reperfusion window (5), magnetic resonance changes in patients with acute ischemic stroke (AIS) beyond the time window were not as important as those within the time window. Meanwhile, several methods have been used to assess the PVS and their association with the clinical outcome. However, a more sensitive predictor of the prognosis of patients with AIS is still unknown. The most common method involves dichotomizing PVS into prominent cortical veins (PCV) and prominent medullary veins (PMV) according to their location. In most previous studies, the clinical significance of PCV and PMV have been analyzed, but rarely did the studies provide conclusive results on whether they had the same clinical value. Hence, in our study, we analyzed PVS in AIS patients within the time window and compared the PCV and PMV in the evaluation of the severity of stroke at baseline and the prognosis at follow-up.     

US diagnosis of choledocholithiasis: a reappraisal

Sonographic detectability of choledocholithiasis using real-time sector scanners appears to be improved in comparison with series previously reported. To establish this premise, 78 consecutive patients with choledocholithiasis were evaluated prospectively by ultrasound (US) prior to surgery or endoscopic retrograde cholangiopancreatography. Preoperative US analysis yielded a 55% sensitivity for detection of choledocholithiasis (43 patients), representing more than a threefold increase over previous series. Dilated extrahepatic ducts were seen in 52 patients (67%), 40 of whom (77%) were seen to have an intraluminal stone. Extrahepatic ducts were normal in size in 26 patients (33%), only three of whom were seen to have a stone. This marked improvement in detection rate probably is related to improvements in imaging technology as well as to increased diagnostic efforts based on cognizance of the difficulty in making the diagnosis of choledocholithiasis sonographically.     

Sonographic parallel channel sign: a reappraisal

Tubular structures proximal to the right and left hepatic ducts, when seen with ultrasonography, are generally considered to be abnormally dilated ducts. However, newer, electronically focused transducers reveal peripheral tubular structures paralleling portal venous branches. The diameters of all visible tubular structures that would have been thought to be bile ducts were measured in 50 persons with no evidence of hepatobiliary disease. "Ducts" were seen with the following frequencies: right hepatic, 100%; right anterior, 100%; right posterior, 88%; left hepatic, 98%; left medial, 62%; left lateral, 96%; left lateral superior, 54%; and left lateral inferior, 54%. All ducts proximal to the right and left hepatic ducts were 2 mm or less in diameter. Those proximal to the common hepatic ducts averaged approximately 20% of the diameters of their accompanying portal veins. Except for 4% of the left lateral inferior ducts, no ducts proximal to the common hepatic ducts were more than 40% the diameter of their respective portal vein branches. Mere observation of parallel channels proximal to the right and left hepatic ducts is therefore not evidence of biliary dilatation.     

Sonographic assessment of normal renal parenchymal and medullary pyramid thicknesses among children in Enugu,Southeast, Nigeria

BackgroundRenal parenchymal thickness (RPT) and renal medullary pyramid thickness (MPT) are important renal size parameters. This study was aimed at establishing normograms for RPT and MPT with respect to age and somatometric parameters among children.MethodsThis was a cross sectional study done in Enugu, Nigeria between May 2013 and April 2014. The subjects were 512 children aged 1–17 years scanned with ultrasound equipment with 3.5 MHz and 5 MHz curvilinear transducers. The RPT was measured perpendicularly to the long axis of the kidney from the medullary papilla to the renal capsule and MPT was measured from the apex to the base of the medullary pyramid on the same plane. The age and somatometric parameters of the subjects were recorded.ResultsThe mean ± SD of RPT and MPT for the right kidney were 12.62 ± 1.67 mm and 7.10 ± 0.92 mm and the left kidney were 12.81 ± 1.7 and 7.23 ± 0.94 mm respectively. There was a significant difference between the right and left RPT and MPT (p < 0.05). The right and left RPT correlated strongly with age, body surface area (BSA), height, and weight but moderately with body mass index (BMI). A moderate positive correlation was observed between MPT and age, BSA, height, and weight. However, a weak correlation was observed between MPT and BMI.ConclusionNormograms of RPT and MPT in relation to age could be useful for grading hydronephrosis in children.     

Bone scintigraphy in lung cancer: a reappraisal

The prognostic significance of bone scintigraphy was investigated by following 587 consecutive patients with lung cancer, in whom this investigation had been performed, for up to 9 years, or until death. Survival was unrelated to age, sex or cell type. However, pain and abnormal bone scintigraphy were both independently associated with a significantly reduced survival compared with those who were free of pain or who had normal bone scintigraphy. These factors were cumulative. The association remained equally valid for all cell types. Claims that a single metastasis is not prognostically significant are unfounded. It is suggested that the results of some chemotherapy trials must be reconsidered in the light of present findings, because of the lack of adequate control groups; the results could be construed to show a beneficial effect only in patients with bone metastases and a poor prognosis, but little or no effect in patients with normal bone scintigraphy. As judged by clinical and radiological follow-up and post-mortem examination, skeletal scintigraphy in patients with lung cancer had a sensitivity of 0.89, a non-specificity (false positives/true negatives) of 0.00 and an accuracy of 0.78. With existing radiopharmaceuticals there is an irreducible residue of false negatives due to deposits which provoke little or no osteoblastic response. Bone scintigraphy is, thus, indicated in any patient with lung cancer with unexplained symptoms and whenever staging is required, because of the prognostic implications. It should precede other staging investigations because the high detection rate may render other tests unnecessary.     

Obstructive pneumonitis: a pathologic and pathogenetic reappraisal

It is widely accepted that pneumonitis distal to an obstructing airway tumor is the result of infection. The authors performed a prospective study to reevaluate this concept and to clarify the nature of the pathologic findings underlying the observed radiographic changes. Specimens were examined for 50 consecutive patients undergoing resection of pulmonary carcinoma. Histologic changes interpreted as noninfectious were found in 42 cases. Findings suggestive of recent or remote infection were also present in nine of these 42 specimens and were localized predominantly in relation to small- to medium-sized airways (acute bronchitis or bronchiolitis); these changes were always present in a background of noninfectious pneumonitis. The authors conclude that the radiographic changes seen in airway obstruction in surgically excised lungs are usually due to consolidation of lung parenchyma by a noninfectious process. When infection does occur, it involves primarily the airways and is not likely to be radiographically detectable.     

一例儿童肾髓质癌的影像表现

患者女 ,11岁.尿液浑浊有泡沫2年,6个月前症状加重于2008年9月10日入院.无发热、恶心、呕吐,无血尿,偶伴腹痛.体检:腹部未扪及明显肿块.尿常规检查:隐血阳性(+++),尿蛋白阳性(+++).尿沉渣检查:白细胞25.3个/μl(正常参考值:0～25个/μl)、红细胞117个/μl(0～15个/μl);末梢血中查见镰状红细胞.     

Clean and dirty shadowing at US: a reappraisal

Clean and dirty shadowing are common phenomena in ultrasound (US) imaging. Clean shadowing is thought to be produced by sound-absorbing materials (ie, stones), and dirty shadowing is thought to be produced by sound-reflecting materials (ie, abdominal gas), but these properties are not consistent. To evaluate the characteristics of shadows behind different objects at US, the authors scanned two renal stones and a bovine femur (each of which had part of its surface artificially smoothed or roughened) and a tissue-mimicking phantom comprising air-containing cylinders of different radii of curvature. The rougher and/or smaller the radius of curvature of the surface insonified by the sound beam, the cleaner was the shadow, independent of the composition of the underlying reflecting medium. Clean and dirty shadowing were primarily related to the properties of the surface of the shadowing object and provided little information about the structural nature of the object.     

Radiogrammetry of the metacarpal: A critical reappraisal

The precise estimation of osteoporosis is hampered by the lack of a generally accepted method of evaluation. Measurement of the combined cortical thickness (CCT) of the centre point of the second metacarpal has been widely used for this purpose, but the wide normal variation found in population studies has reduced its value in the diagnosis of this condition in the individual. The factors leading to this normal variability are discussed and the three centre metacarpals are compared with each other. It is concluded that simple CCT measurement is preferable to any of the indices so far devised, but that a single measurement of a given metacarpal is too imprecise to be of real value. If a single metacarpal is to be chosen, three measurements of the third metacarpal gives a coefficient of variation lower than those of the second or fourth, and an average of nine measurements of the three centre metacarpals produces a further useful reduction in variability.     

Apparent cerebellar ectopia: a reappraisal using volumetric MRI

Cerebellar ectopia, once considered rare, is apparently extremely common on magnetic resonance imaging (MRI). However, assessment of cerebellar position relative to the foramen magnum is usually made from thick sagittal sections and therefore may not be as reliable as sometimes believed. Volumetric MRI, acquired in the coronal plane with section thickness 1.5 mm, was used to assess the position of the cerebel-lum in 144 subjects who also had two-dimensional sagittal imaging using 5.0 mm thick sections. On these images, the frequency of cerebellar ectopia appeared to be 19% (27 cases), but volumetric coronal images indicated that the biventral lobules protruded below the foramen magnum in only 3 (2%), and the cerebellar tonsils lay well above in all cases. Hence the actual frequency of cerebellar tonsillar ectopia in this sample was zero. We concluded that cerebellar ectopia really is rare.     

The nasopharyngeal soft tissue sign: a reappraisal.

An increase in the thickness of the soft tissues of the posterior nasopharyngeal wall has been described in patients with a fracture of the skull base (Andrew, 1978). Measurements of this soft tissue layer made in the same way, in Southampton, have shown a striking difference in the mean and in the normal range both in adolescents and adults. The normal measurements overlap those found in patients with a fracture of the skull base and the sign is not therefore a reliable indication of the presence of such a fracture.     

Brodie abscess: reappraisal.

Upon review, 25 cases of Brodie abscess demonstrated a radiological spectrum not previously appreciated. One third of the lesions were diaphyseal in location, and 50% had associated cortical thickening, while 40% showed a stimulated periosteal reaction, and 20% contained sequestra. The variable radiological appearance was underscored by the fact that the preoperative diagnosis was other than osteomyelitis in half the cases. A diverse nomenclature has proliferated to describe and catalogue bone abscess formation. Although the radiological spectrum is broad, the unanimity of clinical presentation, pathological findings, and response to surgical excision supports the concept of a single entity with variable expression.