Is there a role for magnetic resonance imaging in renal trauma?

BACKGROUND: Computed tomography (CT) has been the most informative imaging method in renal trauma. Despite the good sensitivity of magnetic resonance imaging (MRI) to the presence of hematoma, edema and ischemia, MRI has not been widely studied in patients with renal trauma. The present study was initiated to evaluate the role of MRI in patients with renal trauma. METHODS: Between June 1998 and September 1999, CT and MRI were prospectively performed on 12 patients who suffered from renal trauma and the results reviewed. RESULTS: The presence and size of perirenal hematoma could be detected by both CT and MRI. Magnetic resonance imaging could differentiate intrarenal hematoma from perirenal hematoma more accurately, and provided additional information about the hematoma as T1- and T2-weighted MRI were able to determine recent bleeding in the hematoma by regional differences in signal intensity. Magnetic resonance imaging clearly revealed renal fracture with non-viable fragment and detected focal renal laceration that was not detected on CT due to perirenal hematoma associated with renal infarction. However, although MRI had many advantages over CT, it had also major drawbacks, which were that it required longer imaging time and increased the cost. CONCLUSIONS: Magnetic resonance imaging may be useful in renal trauma. However, it is suggested that MRI should be limited to carefully selected patients, such as those with severe renal injury or equivocal findings on CT.     

Magnetic resonance imaging of brain tumors: Application of gadolinium-DTPA and comparison to computed tomography

In general, CT examinations still seem to be necessary for preoperative classification of brain masses. With increasing experience it should become clear whether sensitivity and specifity of MRI in the diagnosis of brain tumors can be further improved. Although much more work will be necessary in order to establish the optimal dose, timing, and pulse sequences when using Gd-DTPA, this study demonstrates that contrast changes due to Gd-DTPA can have clinical value.     

Computed tomography in cases of multiple sclerosis: Problems of differential diagnosis in cases with atypical findings

The value of computed tomography in the diagnosis of multiple sclerosis is undisputed. The examination is usually carried out as a routine part of the examination program.We report on the CT results of 112 patients with confirmed or suspected MS. Seventy-three patients were examined without, 39 with intravenous administration of a contrast medium. In 41% of the patients, isolated or multiple hypodense foci were found as a manifestation of a multilocular demyelinization process. In 17.8%, only cerebro-at-rophic changes were encountered. In 30.3% of the cases the CT showed normal results. In the group of patients examined with a contrast medium, a pathological contrast medium concentration was found in 30.7%.The differential diagnostic demarcation against other diseases of the CNS with similar CT findings and problems of differential diagnosis with MRI are discussed.     

Imaging medullary cystic kidney disease with magnetic resonance

Medullary cystic kidney disease is characterized by multiple renal cysts at the corticomedullary boundary area, by autosomal dominant inheritance, and by onset of chronic renal failure in the third decade of life. Its clinical manifestations are often insignificant and nonspecific. Furthermore, its diagnosis may be difficult in sporadic forms where genetic linkage analysis cannot be performed. The authors report the case of a patient presenting with a sporadic form of medullary cystic kidney disease whose diagnosis was confirmed using computerized tomography with 3-dimensional reconstruction at the nephrography-excretion time and magnetic resonance imaging (MRI) with magnetic resonance angiography and urography after the injection of gadolinium, a nonnephrotoxic compound. Both imaging techniques showed normal-sized, normal-shaped kidneys containing multiple cysts from 1 to 30 mm in diameter in the medulla and at the corticomedullary junction. A characteristic medullary nephrogram appeared after injection of iodinated contrast medium or gadolinium corresponding to contrast-filled dilated collecting ducts. This report shows that MRI with gadolinium injection can substitute for computerized tomography in azotemic patients. MRI seems particularly promising for the diagnosis of cystic diseases of the kidney and must also be considered when investigating a patient with chronic renal failure of unknown origin.     

子宫内膜间质肉瘤CT、MRI表现

目的分析子宫内膜间质肉瘤(ESS)的CT、MRI表现。方法回顾性分析经术后病理证实为ESS的11例患者的CT、MRI资料。11例中,5例接受CT检查,6例接受MR检查,均包括平扫及增强扫描。结果病理结果为低级别ESS 9例,未分化肉瘤2例。11例病灶均为单发,病灶位于宫腔内7例、肌壁间4例,其中类圆形肿块8例、不规则形肿块3例,病灶最大径(9.18±1.36)cm,肿块边界清晰4例、边界不清7例;病灶CT、MRI表现以实性为主4例、呈囊实性6例、以囊性为主1例。CT平扫示5例病灶实性部分密度均近似于或低于子宫肌层,其中4例病灶密度不均,1例密度均匀。MRI平扫示6例病灶ADC图信号均减低,其中5例呈T1WI等或低信号、T2WI高或稍高信号且DWI呈明显高信号,另1例(以囊性为主)呈T1WI稍高信号、T2WI高信号且DWI呈中心高信号。10例增强扫描表现为渐进性、持续性强化,1例以囊性为主的病灶未见强化。8例肿块内可见囊变、坏死,6例肿瘤浸润、破坏子宫深肌层。11例中,伴子宫腺肌症2例、子宫肌瘤5例,合并少量盆腔积液5例、宫腔内积血1例、输卵管积液2例。结论 ESS的CT、MRI表现具有一定特征,可为诊断提供依据。     

Entrapment radiculopathy: Hypothesis that explains spinal nerve root disorders after spontaneous resorption of lumbar disc herniation

This paper presents ten cases of lumbar spinal nerve root disorder differing from ordinary lumbar disc herniation (LDH) in pathology. The lumbar spinal nerve roots of the ten patients were entrapped or anchored to the posterior longitudinal ligament (PLL), as in entrapment peripheral neuropathy, causing symptoms of radiculopathy similar to LDH. Regression or complete resorption of LDH has been frequently reported. The pathology of perineural conditions after spontaneous resorption, however, has not been expensively studied. We compared disc degeneration in these patients with degeneration in patients with ordinary LDH, based on magnetic resonance imaging (MRI). We also compared the clinical courses in the two groups. The affected discs of 106 patients with low back pain and sciatica, treated operatively for LDH from July 1989 to October 1994 were studied and graded by MRI to assess disc degeneration. Of these 106 patients, 10 exhibited lumbar spinal nerve adhesion to the PLL (entrapment radiculopathy) without herniation mass on myelogram, computed tomography (CT)-myelogram, and MRI. The disc degeneration in the 10 patients showing nerve root entrapment corresponded to that in the 96 patients with LDH. All ten patients had a similar clinical history of recurrent sciatica and low back pain after remission of the first onset, and good results were obtained after neurolysis with free fat grafting, performed to protect against perineural scar formation or adhesions. One patient was follow-up from onset to recurrence by MRI. The pathology “entrapment radiculopathy” may be present in some patients with LDH after spontaneous resorption. Careful follow-up is necessary, even when spontaneous resorption of LDH is recognized by MRI or CT.     

Can magnetic resonance imaging–derived bone models be used for accurate motion measurement with single‐plane three‐dimensional shape registration?

The purpose of this study was to compare three-dimensional (3D) kinematic measurements from single-plane radiographic projections using bone models created from magnetic resonance imaging (MRI) and computed tomography (CT). MRI is attractive because there is no ionizing radiation, but geometric field distortion and poor bone contrast degrade model fidelity compared to CT. We created knee bone models of three healthy volunteers from both MRI and CT and performed three quantitative comparisons. First, differences between MRI- and CT-derived bone model surfaces were measured. Second, shape matching motion measurements were done with bone models for X-ray image sequences of a squat activity. Third, synthetic X-ray images in known poses were created and shape matching was again performed. Differences in kinematic results were quantified in terms of root mean square (RMS) error. Mean differences between CT and MRI model surfaces for the femur and tibia were -0.08 mm and -0.14 mm, respectively. There were significant differences in three of six kinematic parameters comparing matching results from MRI-derived bone models and CT-derived bone models. RMS errors for tibiofemoral poses averaged 0.74 mm for sagittal translations, 2.0 mm for mediolateral translations, and 1.4 degrees for all rotations with MRI models. Average RMS errors were 0.53 mm for sagittal translations, 1.6 mm for mediolateral translations, and 0.54 degrees for all rotations with the CT models. Single-plane X-ray imaging with model-based shape matching provides kinematic measurements with sufficient accuracy to assess knee motions using either MRI- or CT-derived bone models. However, extra care should be taken when using MRI-derived bone models because model inaccuracies will affect the quality of the shape matching results.     

胰腺腺泡细胞癌的CT及MRI影像学分析

目的 分析胰腺腺泡细胞癌（ACC）的CT和MRI特征,提高对该病影像学表现的认识。方法 回顾性分析2007年1月至2016年1月在我院经手术病理或穿刺活检证实的7例ACC患者的CT及MRI影像学资料,其中3例行CT平扫及增强扫描,4例行MRI平扫及增强扫描,观察其影像学表现。结果 男4例,女3例,平均年龄51岁;7例均为单发,病灶位于胰体尾部5例,胰头2例;最大直径约2~13 cm,平均直径5.2 cm,边界较清楚;CT平扫为略低密度,病灶内见不规则更低密度区,未见明显钙化。MRI扫描示病灶T1WI上为混杂稍低信号、T2WI上为混杂稍高信号。CT、MRI增强扫描均见瘤内实性成分动脉期轻度强化,门脉期呈渐进性强化,强化程度低于正常胰腺组织。7例中1例肝转移,1例侵犯临近脾脏,2例显示胰管侵犯并扩张,3例出现腹膜后淋巴结转移。结论 胰腺腺泡细胞癌CT、MRI表现具有一定特征性。     

Two cases of retained foreign bodies after cholecystectomy: Diagnosis by sonography,CT, angiography,and MRI

We encountered two cases of subphrenic abscesses around surgical sponges that had eeen left at cholecystectomy. These cases had been operated on either eight years or seven years earlier, respectively. These lesions resembled another diseases, especially, liver tumors. In order to make a differential diagnosis, various diagnostic procedures were carried out. Sonography showed a cystic mass with spongiform structures in one case. But in another case, no information of internal structures could be obtained because of the presence of a calcified wall. On CT, the lesions appeared as either round or elliptic masses that contained calcified foci in both cases. Angiography showed the extended and compressed branches of the hepatic artery. Spotty stains were also observed in one case. This appearance resembled a hepatic tumor. MR demonstrated both T1 and T2 elongated masses. The internal structures of the mass were clearly revealed by the improved version of the MR machine. MR proved to be extremely useful in making a differential diagnosis. It is, however, important to evaluate the findings of these imaging procedures synthetically and in association with a careful review of a patient's prior surgical history.     

胆囊腺肌瘤病的CT与MRI诊断价值

目的 探讨胆囊腺肌增生症的CT和MRI表现特点,提高诊断正确性.方法 回顾性分析我院2011年8月至2014年3月34例经病理检查证实的胆囊腺肌瘤病(adenomyomatosis of gallbl-adder,GBA)患者的CT和MRI资料.结果 本组行CT检查34例,其中术前确诊为GBA 25例,诊断为慢性胆囊炎5例,漏诊4例;行MRI检查20例,其中术前确诊为GBA 17例,诊断为慢性胆囊炎3例.CT及MRI平扫表现为胆囊壁弥漫性或局限性增厚,部分腔内、外面毛糙不整.增强表现为动脉期黏膜强化,门静脉期强化范围进展,延迟期持续强化,罗-阿氏窦腔内无强化.结论 CT与MRI对胆囊腺肌瘤病有较高的诊断价值,而罗阿氏窦的显示可作为定性的主要诊断依据.     

An unusual case of back pain: A large Pheochromocytoma in an 85 year old woman

INTRODUCTIONLow back ache is a common complaint in the elderly and in the absence of red flag symptoms can be easily dismissed as benign. Pheochromocytoma presenting as back pain is unusual and to our knowledge, only two previous cases have been reported in the literature with back pain as the ‘only’ presenting symptom.CASE PRESENTATIONWe illustrate the case of an 85 year-old woman who presented with a 6 month history of back pain due to a very large Pheochromocytoma. This was incidentally picked up during a routine Lumbar spine plain radiograph and was noted to be a large Pheochromocytoma occupying the whole of the left abdomen. She required an open adrenalectomy to remove the large left adrenal tumour weighing 2.3 kg.CONCLUSIONPheochromocytoma can present as a mimic of musculoskeletal conditions and hence due care should be exercised in assessing such presentations both in the young and elderly patients. Our patient is different from the other reported cases, as she is an 85 year-old and ‘back pain’ can be easily dismissed without investigating in such age groups, thereby missing serious conditions.     

Multi-modality imaging approach to bone tumors - State-of-the art

The approach to the radiographic diagnosis of bone tumors is much beyond the conventional radiographs in present era of multiplanar and functional imaging. Radiographs is still the most pertinent part of initial diagnosis of bone tumors, however, there are few limitations, like lesions in complex anatomy, marrow assessment, soft tissue resolution, which are important for staging. Diagnosis is just one aspect of the tumor evaluation, extent of marrow involvement by the tumor growth, involvement of overlying soft tissue, involvement of adjacent joint, and knowledge about skip lesions and metastasis are equally important for staging and treatment of the disease. Multimodality imaging like CT, MRI helps cover all these aspects. Emerging role of PETCT/PET MRI has further revolutionized the imaging of bone tumors by providing anatomical and morphological characteristics simultaneously and combining the whole body scan in same sitting.This article will discuss the role of various imaging modalities along with illustrative examples of few cases. Team work between radiologist with orthopedic oncologist and pathologist will help in deciding a road map for diagnosing and treatment of bone tumors. Follow up scanning with MRI and PET FDG scan has also been well established in assessing therapeutic response.     

盆腔深部侵袭性血管黏液瘤1例

<正>患者女,29岁,因"发现左下腹包块6个月"入院。查体:左下腹可触及约5 cm×10 cm包块,质硬,活动度可,局部无压痛;肛门指诊胸膝位进指6 cm,未触及肿物,退指后未见指套染血、带脓。CT:盆腔及右侧盆底可见不规则团块样稍低密度肿块影(图1A),约6.5 cm×11.0 cm,边界不清,CT值21～25 HU。MRI:平扫示子宫及阴道后方、直肠右前方团块状异常信号,T1WI呈低信号,T2WI呈高信号(图1B),其内可见条束状、结节状     

肿块型慢性胰腺炎的影像学特征

肿块型慢性胰腺炎包括以纤维化的肉芽组织增生为特征的普通型肿块型慢性胰腺炎和以致密的淋巴浆细胞浸润伴丰富纤维化增生为特征的肿块型自身免疫性胰腺炎两种病理类型,在临床上有时均很难与胰腺癌鉴别。准确的术前诊断与鉴别对于其治疗及预后有着极为重要的意义。肿块型慢性胰腺炎与胰腺癌在CT和MRI上分别具有一定特征性的影像学表现,特别是磁共振动态增强后信号强度-时间（signal intensity-time,SI-T）曲线及弥散加权成像（DWI）更有助于两者的鉴别,肿块型慢性胰腺炎呈慢升慢降型曲线,而胰腺癌呈渐进性升高曲线;肿块型慢性胰腺炎的表现弥漫系数（ADC）值低于胰腺癌的ADC值等。