妊娠高血压综合征致后部可逆性脑病综合征的影像学表现

目的 探讨妊娠高血压综合征(pregnancy-induced hypertension,PIH)致后部可逆性脑病综合征(posterior reversible encephalopathy syndrome,PRES)的影像学特点.方法 3l例PHI患者均行CT平扫,MPd平扫+弥散加权成像(diffusion-weighted imaging,DWI).结果 31例PIH患者CT平扫均可见顶枕叶分水岭区低密度影,CT值19～23 Hu;其中11例MRI表现为T1稍低信号,T2稍高信号,液体衰减反转恢复序列旱高信号,DWI旱等信号,表观弥散系数不下降;临床症状恢复时间早于MRI影像学恢复时间.结论 PIH妊娠晚期发生的PRES的CT和MRI病变部位具有一定特征性,结合病史可明确诊断.     

Study of subclinical cerebral edema in diabetic ketoacidosis by magnetic resonance imaging T2 relaxometry and apparent diffusion coefficient maps

Cerebral edema is the most significant complication in children with diabetic ketoacidosis (DKA). Our goal was to study whether subclinical cerebral edema was preferentially vasogenic or cytotoxic. Magnetic resonance imaging (MRI)--diffusion-weighted imaging (DWI) and T2 relaxometry (T2R)--were obtained in pediatric patients presenting with severe diabetic ketoacidosis (DKA) 6-12 hours after initial DKA treatment and stabilization and 96 hours after correction of DKA. T2 relaxometry was significantly increased during treatment in both white and gray matter, in comparison to the absolute T2R values 96 hours after correction of DKA (p = .034). Classic intracellular cytotoxic edema could not be detected, based on the lack of a statistically significant decrease in ADC values. ADC values were instead elevated, implying a large component of cell membrane water diffusion, correlating with the elevated white and gray matter T2R We discuss the findings in relation to cerebral blood volume, cerebral vasoregulatory dysfunction, and cerebral hyperemia.     

系统性红斑狼疮合并脑后部可逆性脑病综合征的临床分析

目的 脑后部可逆性脑病综合征(PRES)是一种有特征性临床和影像学改变的神经精神综合征.通过分析系统性红斑狼疮(SLE)合并PRES患者的临床表现和复习文献,探讨其发病特点.方法 分析4例确诊为SLE合并PRES患者的临床特点,收集其临床表现、发病诱因和影像学检查资料.结果 4例和文献报道共48例SLE合并PRES患者,发生高血压为42例(88%),血肌酐升高为30例(63%),39例使用激素、免疫抑制剂或细胞毒药物(81%).头痛46例(96%),视觉障碍28例(58%),意识障碍20例(42%),癫痫发作43例(90%),CT及磁共振成像(MRI)显示多发病灶主要位于双侧枕叶、顶叶、额叶、颞叶和小脑.降压和及时处理诱因症状可缓解.结论 PRES是一种临床-影像综合征,常与高血压、肾功能衰竭、免疫抑制剂等药物相关,SLE合并PRES若能快速诊断并给予正确治疗可使症状缓解,病变可逆.     

可逆性后部白质脑病综合征的临床和影像学特征:9例回顾性病例系列研究

目的 探讨可逆性后部白质脑病综合征(reversible posterior leukoencephalopathy syndrome,RPLS)的临床和影像学特征.方法 回顾性分析9例RPLS患者的临床和影像学资料.结果 继发于妊娠高血压综合征4例(44%),短肠综合征1例(11%),急性淋巴细胞白血病1例(11%)...     

Posterior reversible encephalopathy syndrome: another manifestation of CNS SLE?

A variety of neuropsychiatric findings may complicate systemic lupus erythematosus (SLE) and pose diagnostic and therapeutic dilemmas. We describe the clinical and radiographic features of posterior reversible encephalopathy syndrome (PRES) and distinguish PRES from other conditions seen in SLE. Patient charts and magnetic resonance imaging (MRI) findings of four patients with SLE on immunosuppressive therapy with acute or subacute neurologic changes initially suggesting cerebritis or stroke were reviewed. The English language literature was reviewed using the Medline databases from 1996-2006 for other reports of PRES with SLE. Literature review yielded 26 other SLE cases reported with PRES. SLE patients with PRES were more commonly on immunosuppressive drugs, had episodes of relative hypertension, and had renal involvement. Characteristic findings are seen on MRI, which differentiate PRES from other CNS complications of SLE. Clinical and radiographic resolution of abnormalities within 1-4 weeks is typically seen. PRES has been increasingly recognized. Reversible changes are found on brain MRI accompanied by sometimes dramatic signs and symptoms. The therapeutic implications for separating PRES from stroke or cerebritis are important. We propose that PRES should be considered in the differential diagnosis in SLE patients with new-onset neurologic signs and symptoms.     

磁共振扩散加权成像对肝癌TACE术后的影像分析及指导价值

目的探讨磁共振（MR I）扩散加权成像（DW I）对肝癌经导管动脉化疗栓塞术（TACE）术后疗效的影像评估及指导价值。方法搜集30例行TACE治疗的巨块型肝癌患者,于术前24～48 h、术后24～48 h、14～16 d及30～32 d（二次TACE术前）行MR I平扫、增强及DW I扫描,b值选300、600及800 s/mm2,比较不同时间段瘤区组织的平均表现扩散示数（ADC）值的变化并观察同期肿瘤MR I信号变化。结果术后各组肝癌组织的ADC值较术前明显升高（P〈0.05）,术后14～16 d病变ADC值最高,是肿瘤细胞液化、坏死高峰期。术后30～32 d ADC值下降,与二次TACE对比,肿瘤细胞都有不同程度的复发。二次TACE发现病变18处,MR I平扫及增强诊断相符率85.7%。DW I诊断相符率94.7%。不同b值图像分析,b值选600 s/mm2时,图像较清晰,病变敏感性高。结论核磁功能成像DW I对肝癌TACE术后肿瘤细胞残存、复发具有高敏感性、特异性,可有效评估肝癌TACE术后疗效,指导临床治疗方案。     

The pathogenesis of the white matter abnormalities in phenylketonuria. A multimodal 3.0 tesla MRI and magnetic resonance spectroscopy (1H MRS) study

Objective: To gain insights into the nature and pathogenesis of white matter (WM) abnormalities in PKU. Methods: Thirty-two patients with phenylalanine hydroxylase deficiency (21 with early and 11 with late diagnosis and treatment) and 30 healthy controls underwent an integrated clinical, neuroimaging (3.0 T MRI, diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI)) and neurochemical (¹H MRS) investigation. Results: All patients had white matter abnormalities on T2-weighted (T2W) and fluid-attenuated inversion recovery (FLAIR) scans; parietal white was consistently affected, followed by occipital, frontal and temporal white matter. T1-weighted hypointense alterations were also found in 8 of 32 patients. DWI hyperintense areas overlapped with those detected on T2W/FLAIR. The apparent diffusion coefficient (ADC) was reduced and correlated inversely with severity of white matter involvement. Fractional anisotropy index, eigenvalues λ_min, λ_middle, λ_max obtained from DTI data, and the principal brain metabolites assessed by ¹H MRS (except brain phenylalanine (Phe)) were normal. Brain Phe peak was detected in all but two subjects. Brain and blood Phe were strictly associated. Blood Phe at the diagnosis, patient’s age, and concurrent brain Phe independently influence white matter alteration (as expressed by conventional MRI or ADC values). Conclusions: (a) MRI abnormalities in phenylketonuria are the result of a distinctive alteration of white matter suggesting the intracellular accumulation of a hydrophilic metabolite, which leaves unaffected white matter architecture and structure. (b) White matter abnormalities do not seem to reflect the mechanisms involved in the derangement of mental development in PKU. (c) Our data do not support the usefulness of conventional brain MRI examination in the clinical monitoring of phenylketonuria patients. Communicating editor: Georg Hoffmann Competing interests: None declared     

Coincidence of Apical Ballooning Syndrome (Tako-Tsubo/Stress Cardiomyopathy) and Posterior Reversible Encephalopathy Syndrome: Potential Common Substrate and Pathophysiology?

BackgroundApical ballooning syndrome (ABS) and posterior reversible encephalopathy syndrome (PRES) are recently described, seemingly unrelated, reversible conditions. The precise pathophysiology of these syndromes remains unknown. The aim of this study was to describe the clinical characteristics and outcomes of a unique series of patients with both ABS and PRES.Methods and ResultsIn a retrospective study of 224 consecutive patients diagnosed with ABS between 2002 and 2010, 6 (2.7%) were also diagnosed with PRES. All were female with a mean age of 63.7 ± 12.5 years. All patients had preceding medical comorbidities and physical stress triggers that precipitated ABS and PRES. Mean peak troponin T levels and left ventricular ejection fraction at presentation were 0.47 ± 0.48 mg/dL and 31.5 ± 8.2%, respectively. Characteristic left ventricular wall motion abnormalities (regional wall motion score index 2.22 ± 0.37) were noted in all patients, and magnetic resonance imaging of the brain was significant for vasogenic edema, predominantly in the posterior circulation. All patients recovered left ventricular (ejection fraction at follow-up 60.2 ± 6.0%) and neurologic function with supportive management. Two patients had recurrence of ABS and 1 of PRES during follow-up.ConclusionsABS and PRES can occur simultaneously during an acute illness. Patients with ABS who develop neurologic dysfunction should be evaluated for PRES and vice versa. Because transient sympathetic overactivity and microvascular dysfunction have been observed in both reversible syndromes, we speculate that they may represent the shared pathophysiologic mechanism.     

Posterior reversible encephalopathy syndrome--an underrecognized manifestation of systemic lupus erythematosus

OBJECTIVE: Posterior reversible encephalopathy syndrome (PRES) is a rare, recently described neurologic condition identifiable by clinical presentation and magnetic resonance image (MRI) appearance. It is associated with renal insufficiency, hypertension, and rheumatologic diseases. Patients present with headache, seizures, loss of vision and altered mental function, and a pattern on imaging studies of predominantly transient, posterior cerebral hyperintensities on T2-weighted MRI. There is a high likelihood of presentation of this syndrome to a rheumatologist. METHODS: Three recent cases of systemic lupus erythematosus (SLE) with PRES, along with 9 previously reported cases, are reviewed. RESULTS: All 3 patients presented with seizures and subacute visual changes in association with lupus nephritis. The first presented with hypertension, complete visual field loss, and status epilepticus 2 weeks after starting oral cyclosporine therapy for refractory lupus nephritis. The second patient was normotensive and presented with seizures and visual symptoms while in hospital with SLE-related pancreatitis and nephritis. The third patient had headache and seizures with severe lupus disease activity including nephritis, pancytopenia, and pulmonary hemorrhage. Cranial MRI showed predominantly posterior signal abnormalities on T2-weighted images, which resolved after cessation of cyclosporine in the first case, treatment with IV cyclophosphamide in the second case, and treatment with cyclophosphamide and plasmapheresis in the final case. Literature review showed that PRES is a manifestation of SLE or a consequence of therapy with calcineurin inhibitors or rituximab. The hallmark features are visual loss and seizures. Severe hypertension (> 170/110 mm Hg) and renal failure were present in the majority of previously identified cases of SLE and PRES. Our second case was normotensive but had marked lupus disease activity. PRES can lead to cerebral infarction. CONCLUSION: With increasing availability of MRI, PRES will be identified more frequently. Swift action to identify potential offending agents, controlling hypertension, and treating active disease can lead to reversal of radiologic and neurologic findings.     

Role of diffusion-weighted magnetic resonance imaging in the diagnosis of extrahepatic cholangiocarcinoma

AIM: To determine the clinical value of diffusion-weight- ed imaging (DWI) for the diagnosis of extrahepatic cholangiocarcinoma (EHCC) by comparing the diagnostic sensitivity of DWI and magnetic resonance cholan-giopancreatography (MRCP). METHODS: Magnetic resonance imaging examination was performed in 56 patients with suspected EHCC. T1- weighted imaging, T2-weighted imaging, MRCP and DWI sequence, DWI using single-shot spin-echo echoplanar imaging sequence with different b values (100, 300, 500, 800 and 1...     

Posterior reversible encephalopathy syndrome during systemic lupus erythematosus: four new cases and review of the literature

Posterior reversible encephalopathy syndrome (PRES) associates various neurological manifestations (headaches, seizures, altered mental status, cortical blindness, focal neurological deficits, vomiting) and transient changes on neuroimaging consistent with cerebral edema. Posterior reversible encephalopathy syndrome mainly occurs in the setting of hypertension, eclampsia, renal failure and/or use of immunosuppressive drugs.We report four cases of PRES complicating systemic lupus erythematosus (SLE). In all our cases, renal involvement and hypertension were present. Neurological symptoms were typical. Magnetic resonance imaging showed posterior cerebral edema and in one case hemorrhagic complication. With symptomatic treatment and immunosuppressor withdrawal when they were previously used, symptoms fully resolved within 15 days in all cases, but one who had only partial regression related to cerebral hemorrhage.Including our cases, we reviewed a total of 46 patients with SLE and PRES. Their clinical and radiological presentation was not specific. The peculiar role of SLE itself in the occurrence of PRES was not clear, since hypertension (95%), renal involvement (91%), recent onset of immunosuppressive drugs (54%) and/or recent treatment with high intravenous dose of steroids (43%) were often present. The hypertension and other worsening factors should be treated. Finally, the evolution of this clinical and radiological spectacular syndrome is generally rapidly favorable.     

Nephrotic Syndrome and Atypical Posterior Reversible Encephalopathy Syndrome in a Patient with Parkinson's Disease

A 59-year-old man with advanced Parkinson''s disease treated using levodopa-carbidopa intestinal gel (LCIG) presented with leg edema, hypoalbuminemia, and proteinuria at 1 year after the treatment. He subsequently developed a generalized tonic-clonic seizure, and brain magnetic resonance imaging indicated vasogenic edema in the white matter of the left frontal subcortex. He was diagnosed with nephrotic syndrome (NS) and atypical posterior reversible encephalopathy syndrome (PRES). LCIG cessation and corticosteroid treatment improved the NS. To our knowledge, this is the first case report of NS and atypical PRES in patients with Parkinson''s disease. Patients being treated with LCIG should be closely monitored for NS.     

Two similar cases of encephalopathy, possibly a reversible posterior leukoencephalopathy syndrome: serial findings of magnetic resonance imaging, SPECT and angiography

Two young women who had encephalopathy that resembled reversible posterior leukoencephalopathy syndrome are presented. The brain magnetic resonance imaging (MRI) of these patients exhibited similar T2-high signal lesions, mostly in the white matter of the posterior hemispheres. Xe-SPECT during the patients' symptomatic period showed hypoperfusion in the corresponding areas, and angiography demonstrated irregular narrowing of the posterior cerebral artery. Clinical manifestations subsided soon after treatment, and the abnormal radiological findings also were almost completely resolved. Thus, we concluded that transient hypoperfusion followed by ischemia and cytotoxic edema might have had a pivotal role in these cases.     

磁共振弥散加权成像ADC值和骨髓对比率在脊柱转移瘤的应用研究

目的探讨MR弥散加权成像（DWI）的表观弥散系数（ADC）值和骨髓对比率对脊柱转移瘤的诊断价值。方法脊柱占位性病变组和正常对照组各40例,均进行MRI常规扫描和b值为500 s/mm2的DWI,测量ADC值和骨髓对比率。结果椎体转移瘤病灶的ADC值比正常椎体高（P〈0.05）,DWI骨髓对比率高于常规MR增强扫描（P〈0.05）。结论应用DWI的ADC值和骨髓对比率可提高对脊柱转移瘤的诊断和鉴别诊断能力。     

Role of diffusion-weighted magnetic resonance imaging in the differential diagnosis of focal hepatic lesions

AIM: To evaluate the utility of diffusion-weighted imaging (DWI) in screening and differential diagnosis of benign and malignant focal hepatic lesions. METHODS: Magnetic resonance imaging (MRI) examinations were performed using the Signa Excite Xl Twin Speed 1.5T system (GE Healthcare, Milwaukee, WI, USA). Seventy patients who had undergone MRI of the liver [29 hepatocellular carcinomas (HCC), four cholangiocarcinomas, 34 metastatic liver cancers, 10 hemangiomas, and eight cysts] between April 2004 and August 2008 were retrospectively evaluated. Visualization of lesions, relative contrast ratio (RCR), and apparent diffusion coefficient (ADC) were compared between benign and malignant lesions on DWI. Superparamagnetic iron oxide (SPIO) was administered to 59 patients, and RCR was compared pre- and postadministration. RESULTS: DWI showed higher contrast between malignant lesions (especially in multiple small metastatic cancers) and surrounding liver parenchyma than did contrast-enhanced computed tomography. ADCs (mean ± SD × 10~(-3) mm~2/s) were significantly lower ( P < 0.05) in malignant lesions (HCC: 1.31 ± 0.28 and liver metastasis: 1.11 ± 0.22) and were significantly higher in benign lesions (hemangioma: 1.84 ± 0.37 and cyst: 2.61 ± 0.45) than in the surrounding hepatic tissues. RCR between malignant lesions and surrounding hepatic tissues significantly improved after SPIO administration, but RCRs in benign lesions were not improved. CONCLUSION: DWI is a simple and sensitive method for screening focal hepatic lesions and is useful for differential diagnosis.     

中老年人自身免疫性胰腺炎的磁共振表现

目的 探讨中老年人自身免疫性胰腺炎(AIP)的磁共振(MRI)特征. 方法 17例经组织学或类固醇激素治疗证实的中老年AIP患者,均接受MRI检查,对患者的临床和MRI资料进行回顾性分析. 结果 17例中老年AIP中,13例AIP表现为胰腺弥漫性肿大,4例为局限性肿大或局限性信号异常.病变T_1WI上呈明显低信号,在T_2WI上呈轻度高信号,动脉期强化减弱但呈现明显的延时强化.13例在胰腺病变周围环绕包膜样结构.15例AIP伴有胰腺段胆总管的狭窄,5例胰胆管磁共振显示胰管不规则狭窄.11例AIP的平均表观扩散系数值为1.64×10~3mm~2/s. 结论 AIP好发于中老年人;其MRI特征包括胰腺呈香肠样或香蕉样肿大、病变胰腺周围延迟强化的包膜样影、胰管弥漫不规则狭窄等,MRI既可用于诊断AIP,也是评价其疗效的重要手段.     

Lupus anticoagulant: correlation with magnetic resonance imaging of brain lesions.

Brain magnetic resonance imaging (MRI) was performed in 21 patients with systemic lupus erythematosus (SLE) with and without lupus anticoagulant (LAC), one lupus-like patient and 5 patients with primary antiphospholipid antibody syndrome. Thirteen patients had white matter focal brain lesions on MRI, 10 of whom had LAC (p = 0.03). We found no correlation between these lesions and neurologic manifestations, nor any clinical or serologic indices of activity of SLE. Our MRI lesions were similar to those described in multiple sclerosis and may indicate a similar pathologic process.     

Primary Hyperparathyroidism Presenting as Posterior Reversible Encephalopathy Syndrome: A Report of Two Cases

Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological entity characterized by subcortical vasogenic edema presenting with acute neurological symptoms. Common precipitating causes include renal failure, pre-eclampsia/eclampsia, post-organ transplant, and cytotoxic drugs. Hypercalcemia is a rare cause of PRES; most cases occur in the setting of severe hypercalcemia secondary to malignancy or iatrogenic vitamin D/calcium overdose. Primary hyperparathyroidism (PHPT), as a cause of PRES, is an oddity. We report two cases of adolescent PHPT presenting with generalized tonic-clonic seizures and altered sensorium. On evaluation, both had hypertension, severe hypercalcemia (serum calcium 14.1 mg/dL and 14.5 mg/dL, respectively) and elevated parathyroid hormone levels. Magnetic resonance imaging (MRI) revealed T2/fluid-attenuated inversion recovery hyperintensities located predominantly in the parieto-occipital regions, suggestive of PRES. Identification and excision of parathyroid adenoma led to the restoration of normocalcemia. Neurological symptoms and MRI changes improved subsequently. An extensive literature search revealed only four cases of PHPTassociated PRES; none of them being in the pediatric/adolescent age group. The predominant clinical manifestations were seizures and altered sensorium. All had severe hypercalcemia; three had hypertension at presentation, while one was normotensive. Parathyroid adenomectomy led to normalization of serum calcium and resolution of neurological symptoms and radiological changes. Thus, severe hypercalcemia, although rare in PHPT, can lead to hypercalcemic crisis precipitating acute hypertension that can result in cerebral endothelial dysfunction with the breakdown of the blood-brain barrier, culminating in PRES. We therefore recommend that serum calcium levels should be checked in all patients with PRES and that PHPT be regarded as a differential diagnosis in those with underlying hypercalcemia.     

Acute pancreatitis successfully diagnosed by difffusion-weighted imaging: A case report

Diffusion-weighted imaging (DWI) is an established diagnostic method of acute stroke.The latest advances in magnetic resonance imaging (MRI) technology have greatly expanded the utility of DWI in the examination of various organs.Recent studies have revealed the usefulness of DWI for imaging of the liver,kidney,ovary,and breast.We report a patient with acute pancreatitis detected by DWI and discussed the efficacy of DWI in diagnosing acute pancreatitis.A 50-year old man presented with a primary complaint of abdominal pain.We performed both DWI and computed tomography (CT) for this patient.The signal intensity in a series of DWI was measured and the apparent diffusion coefficient (ADC) values were calculated to differentiate inflammation from normal tissue.Two experienced radiologists evaluated the grade of acute pancreatitis by comparing the CT findings.Initially,the pancreas and multiple ascites around the pancreas produced a bright signal and ADC values were reduced on DWI.As the inflammation decreased,the bright signal faded to an iso-signal and the ADC values returned to their normal level.There was no difference in the abilities of DWI and CT images to detect acute pancreatitis.However,our case indicates that DWI can evaluate the manifestations of acute pancreatitis using no enhancement material and has the potential to replace CT as a primary diagnostic strategy for acute pancreatitis.     

磁共振弥散加权成像对急性胰腺炎严重性分级的诊断价值

目的 探讨磁共振弥散加权成像（DWI）及表观弥散系数（ADC）值对急性胰腺炎（AP）严重性分级的诊断价值.方法 收集57例AP及13例正常胰腺含有DWI的磁共振成像（MRI）资料.参照Balthazar CT分级标准,将AP的MRI表现分为相应的A、B、C、D、E5级,测量炎症胰腺及正常胰腺的ADC值.应用单因素方差分析（ANOVA）对各级别AP之间、各级别与正常胰腺之间的ADC值进行统计学分析.结果 57例AP的MRI分为A级6例,B级9例,C级11例,D级10例,E级21例.炎症胰腺在DWI图像均呈高信号（100％）.A、B、C、D、E级AP的平均ADC值分别为（1.138 ±0.024）、（1.289±0.179）、（1.513 ±0.156）、（1.554 ±0.248）、（1.938±0.567） ×10-3 mm2/s,正常胰腺的ADC值为（1.687±0.129）×10-3mm2/s.A、B级AP的ADC值显著低于E级（P值均＜0.01）及正常胰腺（P值均＜0.05）,C级的ADC值低于E级（P＜0.05）,其余各级别之间,C、D、E级与正常胰腺之间的ADC值差异均无统计学意义（P值均＞0.05）.结论 磁共振DWI有利于Balthazar分级中形态变化不明显的A级及B级AP的早期诊断,但ADC值对AP严重性的分级诊断无明显价值.