Imaging and clinical features of xanthogranulomatous pancreatitis: an analysis of 10 cases at a single institution

Purpose

The purpose of the study was to investigate the imaging and clinical features of xanthogranulomatous pancreatitis (XGP).

Methods

This retrospective series study included 10 patients with pathology-proven XGP. Two radiologists reviewed the computed tomography (CT) and magnetic resonance imaging (MRI) in consensus to determine the morphological features of XGP. The lesion enhancement pattern on dynamic contrast-enhanced scans and the MR signal intensity were also evaluated. Clinical data including symptoms, underlying pancreatic disease, and laboratory findings were reviewed.

Results

Two XGP cases were of a solid type; six were of cystic type, and two were mixed type. XGP usually showed a lobulated contour (90%) and heterogeneous enhancement (100%), with lesion size varying from 2 to 11 cm. Perilesional infiltration was common (90%), but pancreatic duct dilatation was less frequent (30%). Cystic type XGP mostly had an irregular thick wall (83%). On dynamic contrast-enhanced CT/MRI, XGP enhanced progressively from arterial to portal or delayed phases. Lesions appeared hypointense on T1-weighted images (89%) and hyperintense on T2-weighted images (100%). All lesions appeared hyperintense on diffusion-weighted images, with the majority (78%) showing diffusion restriction on apparent diffusion coefficient maps. The patients often had abdominal pain (80%) and underlying pancreatic disease (80%), but mostly had normal or clinically insignificant laboratory findings.

Conclusions

XGP typically manifests as a clinically silent lobulated heterogeneous mass, with a progressive enhancement pattern and/or irregular thick wall, and diffusion restriction on CT/MRI. Awareness of the imaging and clinical features of XGP may help differentiate it from pancreatic neoplasms, thereby reducing unnecessary surgery.

     

脊椎骨巨细胞瘤的CT、MRI表现及临床研究

目的分析脊椎骨巨细胞瘤的CT、MRI表现,提高对该病的术前诊断及更好地指导临床。方法回顾性分析经临床病理证实的11例脊椎骨巨细胞瘤的CT和MRI。结果11例中肿瘤位于颈椎2例,胸椎4例,腰椎4例,骶椎1例。CT表现为椎体和/或附件溶骨性破坏区;内见不规则骨嵴分隔;椎旁软组织肿块内部或周边见线样高密度钙化影。MRI信号表现具有多样性,T1WI呈等/低信号;T2WI和STIR上肿瘤实性部分呈中等或稍高信号,囊变和出血区呈高信号;1例可见液-液平面。结论脊椎骨巨细胞瘤具有一定的CT、MRI表现特征,对术前正确诊断、临床分期、手术方式选择和术后处理有重要价值。     

胰岛素瘤的MSCT和MRI特征

目的 探讨胰岛素瘤的MSCT和MRI特征,提高对该肿瘤的定位和定性诊断能力.方法 回顾性分析经手术病理证实的18例胰岛素瘤患者的影像学资料,对12例行CT检查,1例仅行CT平扫,7例仅行三期动态增强扫描,4例同时行平扫和增强检查;16例行MR检查,其中4例同时行三期动态增强扫描;9例同时行CT和MR检查.结果 18例均为单发胰岛素瘤;8例发生在胰头(5例在钩突部),1例在胰颈,5例在胰体,4例在胰尾.CT平扫均为阴性;三期动态增强检查,11例中9例呈富血供表现,1例呈乏血供表现,1例漏诊.MR平扫肿瘤在T1WI上呈低信号,T2WI上呈等、稍高或混杂信号;4例行MR动态增强检查,均呈富血供表现.所有肿瘤边界清楚,均无血管、胰管和胆管受侵及肝转移表现.结论 胰岛素瘤有较为典型的MSCT和MRI表现,MSCT及MR检查对胰岛素瘤的定位和定性诊断有重要价值.     

肾血管瘤CT和MRI特征分析

目的 探讨肾血管瘤的CT和MRI特征,为其诊断进一步提供参考。方法 回顾性分析经手术病理证实的10例肾血管瘤患者的临床特征及影像表现,其中3例行CT、5例行MRI、2例同时行CT和MRI检查,总结其影像特征。结果 10例肾血管瘤中,7例为吻合状血管瘤,6例位于肾髓质、3例位于肾窦、1例位于肾实质,肿瘤最大径1.4～6.4 cm,8个病灶表现为类圆形。所有病灶均以实性为主,3例有包膜。4例T₂WI呈明显高信号,6例DWI呈高信号;在ADC图上3例呈等信号,2例呈高信号,2例呈低信号;8例表现为皮髓质期瘤周明显结节、斑片状强化,后期逐渐向中心填充,1例明显不均匀强化,1例不强化。CT多期增强扫描中,肾血管瘤实质期强化率高于腹主动脉(P<0.05),皮髓质期强化率与腹主动脉差异无统计学意义;肾血管瘤在MRI增强扫描皮髓质期及肾实质期的强化率与肾皮质及腹主动脉差异无统计学意义。结论 肾血管瘤好发于肾髓质或肾窦部,多为吻合状血管瘤;影像表现具有一定的特征性：T₂WI多呈明显高信号,动态增强扫描中皮髓质期病灶周边明显结节样强化,逐渐向中心填充,强化...     

Antenatal sonographic appearance of a large orbital encephalocele: A case report and differential diagnosis of orbital cystic mass

Orbital meningoceles and encephaloceles are rare extracranial extensions of the brain and meninges with or without direct communication between the central nervous system and the abnormal mass. We reported a rare case of large fetal orbital encephalocele; the diagnosis was suspected initially by prenatal ultrasound and confirmed by postnatal MRI and CT scans. The differential diagnosis of an intrauterine fetal cystic orbital mass includes orbital teratoma, epidermoid inclusion cysts, hemangioma or lymphangioma, congenital cystic eye, dacryocystocele, and orbital cephalocele. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 41:327–331, 2013     

SAPHO综合征的影像表现

目的 探讨SAPHO综合征的影像学表现。方法 回顾性分析20例SAPHO综合征患者的影像学表现。结果 19例病变累及前上胸壁,X线、CT表现为骨及肋软骨硬化、肥厚,关节破坏、强直,胸骨柄、锁骨近端和第1肋软骨受累,其中双侧不对称受累8例,双侧对称性受累7例,单侧受累4例。10例柄胸联合受累,6例第2肋软骨受累。5例伴有脊柱病变,X线、CT表现为多发椎体终板侵蚀、硬化,椎旁骨化,椎间隙变窄,椎体楔形变;MRI表现为椎体不均匀长T1长T2信号。3例伴骶髂关节受累,X线和CT表现为关节破坏、强直。结论 前上胸壁病变是SAPHO综合征最具特征性的影像学表现。     

颅骨动脉瘤样骨囊肿CT及MRI表现

目的 观察颅骨动脉瘤样骨囊肿的CT和MRI表现。方法 回顾性分析8例经手术病理证实的颅骨ABC患者的CT和MRI图像,发生于脑颅骨者5例,其中枕骨3例,顶骨1例,颞顶枕骨1例,发生于颌骨2例,发生于颅中凹1例、累及蝶骨、颞颌关节。对8例均行CT平扫和MRI常规平扫,位于脑颅骨的5例同时行MR常规增强扫描,位于颅中凹的1例加做MR动态增强扫描、并后处理得到时间-信号强度曲线(TIC)及其半定量参数。结果 CT表现:8例均表现为单房或多房状膨胀性骨质破坏区伴内部骨质分隔影,其内软组织肿块密度不均匀,内见斑片状低密度区。位于颅中凹的1例骨质破坏范围较大,对周围组织具有侵袭性。MRI表现:8例病变均表现为病变主体呈等长T1长T2信号,病变内部含有数量、大小不等的囊性部分,信号不均一,其中5例病灶囊内可见液-液平面,8例病变边缘均可见低信号界线。位于颅中凹的1例TIC呈平坦型,峰值信号强度(SI_peak)为1080,峰值时间(T_peak)为第9个时相,最大上升斜率(MSI)为0.81%。结论 颅骨ABC具有较为典型的影像学征象。     

Usefulness of 18FDG-PET/CT and MRI in an immunocompetent patient with fever of unknown origin and following diagnosis of skeletal tuberculosis: A case report

IntroductionFever of unknown origin (FUO) is one of the most difficult diagnostic dilemmas in current medicine. The main causes of FUO in developed countries are non-infectious inflammatory diseases, while infections are predominant in developing countries. Among infections, Mycobacterium Tuberculosis (TB) is the most frequent cause and it can involve multiple tissues and organs.Case and outcomesWe report a case of FUO in an immunocompetent patient with fever of unknown origin, finally diagnosed with skeletal TB thanks to a multidisciplinary approach, using FDG-PET/CT, MRI, and biopsy. PET/CT findings were non-specific (infection or inflammation versus malignancy); therefore, hip Magnetic Resonance Imaging (MRI) was performed and infection was suspected on basis of MRI findings, so a bone biopsy was then performed and skeletal TB was diagnosed.DiscussionA successful diagnostic workup of FUO has to take into account detailed medical history, physical examination, laboratory tests, blood and urine cultures, and standard imaging (Ultrasonography, CT, or MRI). However, this combination of clinical evaluation, standardized laboratory tests and simple imaging procedures often do not lead to a definite diagnosis; ⁸F-FDG-PET-CT could be performed to help in diagnosis and also to guide additional diagnostic tests such as MRI and biopsy.ConclusionThis case demonstrates the importance of the integration of different imaging modalities, in particular, MRI and FDG-PET/CT in patients with FUO. Skeletal TB should always be included in the diagnostic hypothesis of FUO, even in immunocompetent patients of non-endemic countries.     

舌根异位甲状腺的CT和MRI表现

目的 探讨舌根异位甲状腺的CT和MRI表现. 方法 回顾性分析8例经核素扫描或手术证实的舌根异位甲状腺患者的CT或MRI资料,其中6例接受颈部CT检查,2例接受颈部MR检查. 结果 8例病灶均位于舌根中线区,6例呈类圆形,2例呈分叶状,边界清楚,最大径16～36 mm,平均24 mm.与舌根肌肉比较,2例CT平扫呈高密度,其中1例密度不均匀;5例增强后明显强化,其中2例病灶内有散在的小囊状低密度区;3例病变密度不均匀,结合其他检查考虑伴发结节状甲状腺肿,其中1例经病理证实.2例MR T1WI、T2WI均呈较高信号,增强后明显强化,病变信号较均匀.颈部均未发现正常位置的甲状腺. 结论 舌根中线区高密度或高信号并明显强化的结节是舌根异位甲状腺的特征性影像学表现,密度或信号不均匀常提示其发生病变;结合颈部无正常位置甲状腺,比较容易作出诊断.     

胰腺损伤的影像学诊断

目的 探讨多层螺旋CT及MRI检查在评价胰腺损伤中的价值.方法 回顾性分析经手术和临床随访证实的10例闭合性腹部外伤致胰腺损伤的CT/MRI表现.男6例,女4例,年龄5～52岁,平均年龄(27.60±12.34)岁.CT检查7例,MRI检查5例,其中2例分别进行了CT和MRI检查.结果胰腺损伤CT/MRI表现为胰腺肿大(CT 5例,MR 2例);胰腺断裂(CT 5例,MR 4例);主胰管断裂(CT 1例,MR 4例);胰腺内/胰周出血(CT 3例,MR 1例);胰腺裂伤(CT 2例,MR 1例);胰周改变 胰周被膜和肾周筋膜增厚以及胰周、肾旁间隙广泛积液(CT 6例,MR 5例);假性囊肿形成(CT 4例,MR 2例);合并腹部其他脏器损伤CT显示肝、肾损伤各1例,脾损伤2例,MR显示脾损伤1例.结论 多层螺旋CT和MRI在胰腺损伤的诊断中有重要价值.     

黏液性脂肪肉瘤的CT、MRI表现

目的 探讨黏液性脂肪肉瘤的CT、MRI表现特征。 方法 回顾性分析经手术病理证实的24例黏液性脂肪肉瘤的CT、MRI表现特点。18例术前接受CT平扫,其中9例同时接受增强扫描;6例接受MR平扫,其中5例同时接受增强检查。 结果 24例黏液性脂肪肉瘤均表现为单发结节或肿块;发生于下肢(n=12)尤其大腿(n=9)最为多见,其次是腹膜后(n=7);发生于四肢的14例患者中,病变位于肌间隙10例(n=10),肌肉内2例(n=2),皮下脂肪层内2例(n=2);15例肿瘤形态规则,边界尚清,9例形态不规则,边界不光整,可见分叶等征象;病灶最大径2.0~38.0 cm,平均(12.5±8.0)cm。18例CT平扫CT值11.0~30.0 HU,平均(19.4±6.8)HU;6例MR平扫T1WI病变与肌肉相比以等或稍低信号为主,2例内见云絮状高信号;4例T2WI病变与皮下脂肪相比以明显高信号为主,内有稍高信号区和(或)线样低信号分隔,2例呈均匀显著高信号;14例CT和MR增强后病变均表现为明显不均匀强化;CT强化最显著区CT值35.0~112.0 HU,平均(62.7±27.0)HU。 结论 黏液性脂肪肉瘤的CT、MRI表现有一定特征,CT平扫多为囊样低密度影,MRI以T1WI低信号、T2WI显著高信号为主,T2WI可伴稍高信号区和(或)线样低信号分隔,增强后多呈显著不均匀强化。     

亚病灶肝细胞癌变的发育不良性结节的CT诊断

目的研究亚病灶肝细胞癌变的发育不良性结节(DN-SF-HCC)的CT表现和诊断.方法回顾性分析3个病理确诊的DN-SF-HCC者的CT资料.结果在常规的UCT和增强CT上呈"混杂-等"、在螺旋CT的UCT、HACT、PVCT和DCT上分别呈"高-高-等"和"低-高-等-等"密度者各1例;1例确诊,2例诊为肝癌.结论 DN-SF-HCC的CT表现多种多样,为提高诊断水平,需进一步研究.     

The Performance of Radiographic Criteria for Bone Malignancy When Applied to Computed Tomography and Magnetic Resonance Imaging

BackgroundThe conventional radiologic features that differentiate benign from malignant bone lesions were originally described using radiography (x-ray [XR]). When evaluating sectional imaging studies such as magnetic resonance imaging (MRI) and computed tomography (CT), one may apply these principles to identify malignant bone lesions. The aim of this study was to evaluate the performances of these radiographic features for detecting malignity when applied to CT and MRI.Materials and MethodsThis retrospective study was approved by our institutional ethical board. Thirty-nine patients with histopathologic proof of a high-grade bone malignancy and preoperative imaging data obtained with a minimum of two different modalities were included in the study. Four radiologists reviewed the images and scored the lesions for distinctness of margins, presence and type of periosteal reaction, matrix mineralization, and presence of soft tissue mass. The average score for each modality was then tested for accuracy with regard to the histopathology.ResultsWhen lesion margins were considered, XR was the best modality to detect a high-grade malignancy. MRI, especially postcontrast T1-weighted sequence, was the least helpful in this regard. There was no significant difference between CT and XR and between CT and MRI. When the periosteal reaction was considered, XR was the best modality to detect the malignant type of periosteal reaction. In this regard, MRI and CT were misleading; either by not detecting or undergrading periosteal reaction. MRI was the best modality to detect soft tissue mass.ConclusionConventional imaging criteria for bone malignancy can be misleading when applied to MRI or CT. When cross-sectional imaging features contradict those from XR, the latter should be the guide for clinical management.     

细支气管肺泡癌的薄层CT诊断(附65例报告)

目的：探讨细支气管肺泡癌在簿层ＣＴ上的表现与意义。资料与方法：搜集１９９４年１２月至１９９６年１２月经薄层ＣＴ扫描和病理证实的６５例细支气管肺泡癌。扫描方法：先以１０ｍｍ层厚，１２５ｋＶｐ，２５０ｍＡｓ，自肺尖到肺底逐层扫描，然后对病变区行１～１．５ｍｍ层厚薄层扫描并放大。结果：６５例细支气管肺泡癌的ＣＴ表现可分为五型：（１）孤立结节型，（２）肿块型，（３）斑片型，（４）弥漫型，（５）混合型。结论：薄层ＣＴ扫描对细支气管肺泡癌的诊断很有价值。     

Hepatopulmonary shunting on Tc99m-MAA liver mapping: correlation with dynamic cross-sectional imaging and description of different shunting patterns

Purpose

The purpose of the study was to correlate lung shunt fraction (LSF) calculated by intra-arterial injection of Technetium-99m (Tc-99m)-labeled macroaggregated albumin (MAA) in a hepatic artery branch with the presence of certain patterns of vascular shunts on dynamic CT or MRI of the liver.

Methods

This retrospective study was approved by the institutional review board and informed consent was waived. We reviewed 523 MAA scans in 453 patients (301 men, 152 women) performed from July 2007 to June 2015 and their correlative cross-sectional imaging. Patterns of vascular shunts on dynamic CT or MRI performed within 3 months of the MAA study and that potentially divert hepatic arterial inflow to the systemic venous return were defined as “target shunts.” Dynamic CT or MRI was classified into three groups with target shunt present, absent, or indeterminate. The mean LSF was compared across the first and second groups using paired t test.

Results

342 CT and MRI studies met inclusion criteria: target shunts were present in 63 studies, absent in 271 studies, and 8 studies were indeterminate. When target shunts were visualized, the mean LSF on corresponding MAA scans was 12.9 ± 10.36% (95% CI 10.29–15.15%) compared to 4.3 ± 3.17% (95% CI 3.93–4.68%) when no target shunt was visualized. The difference was statistically significant (p value < 0.001). Identified target shunts were either direct (arteriohepatic venous shunt) or indirect (arterioportal shunt combined with a portosystemic shunt).

Conclusions

Visualizing certain patterns of vascular shunting on a dynamic CT or MRI scan is associated with high LSF.

     

肾脏罕见良性肿瘤的影像学表现与临床病理对照分析

目的 分析肾脏罕见良性肿瘤的影像学表现.方法 回顾性分析15例经手术病理证实的肾脏罕见良性肿瘤的影像学资料,包括肾嗜酸细胞腺瘤5例,上皮样血管平滑肌脂肪瘤3例,孤立型纤维瘤3例,后肾腺瘤、血管瘤、平滑肌瘤和球旁细胞瘤各1例;其中12例接受CT检查,3例接受MR检查.结果 11例CT或MR平扫显示边界清楚的实性肿块.肾嗜酸细胞腺瘤明显不均匀强化,体积较大者可出现中央瘢痕.上皮样血管平滑肌脂肪瘤MR T1WI、T2WI均以低信号为主,内夹杂索条状、斑片状高信号以及流空信号.血管瘤呈渐进性向心性强化,易发生囊变;孤立型纤维瘤T1WI和T2WI均为低信号,增强后延迟强化.后肾腺瘤、平滑肌瘤和球旁细胞瘤缺少特征性影像学表现.结论 肾脏罕见良性肿瘤大多边界清晰,影像学表现多有一定特征性,对术前诊断有所帮助.     

肝脏血管平滑肌脂肪瘤的CT及MRI表现

目的 分析肝脏血管平滑肌脂肪瘤的CT及MRI征象特点。方法 回顾性分析经手术病理证实的7例肝脏血管平滑肌脂肪瘤患者的CT和/或MRI表现,并与病理结果进行对照。结果 CT及MRI平扫共8个病灶,CT显示6个病灶中,5个呈稍低密度,1个病灶大部分呈低密度,其内可见小片状等密度。MR显示的4个病灶中,2个脂肪抑制T2WI呈低信号,T1WI呈较均匀低信号,1病灶未显示脂肪信号特点,病灶内未见囊变、血肿、坏死等信号。增强扫描动脉期7个病灶表现为明显不均匀强化,1个病灶呈均匀强化;3个病灶呈"快进快出"强化改变,5个病灶呈持续强化改变;3个病灶内部见粗大畸形血管,5个病灶可见引流静脉。结论 肝脏血管平滑肌脂肪瘤的影像学表现有一定特征性,影像学检查有助于诊断和鉴别诊断。     

眼眶孤立性纤维瘤的CT及MRI特点

目的 探讨眼眶孤立性纤维瘤(SFT)的CT及MRI表现特点.方法 回顾性分析7例经手术病理证实的眼眶SFT的CT及MRI资料.结果 7例SFT均为单发,边缘界限清晰,病灶最大直径17～4 5 mm;跨肌锥内、外生长1例,肌锥外2例,肌锥内4例. 6例接受CT平扫,均表现为等密度肿块,内未见出血、囊变及钙化. 4例接受MR平扫,其中3例T1WI呈等信号,1例呈稍低信号;3例T2WI呈稍高信号,1例呈等信号;2例于T2Wl可见小囊样高信号囊变区;4例于T1WI或T2WI可见管状或分支状的血管流空信号. 6例CT或MRI增强后明显强化,其中3例CT强化方式为快进快出.结论 增强后病灶呈快进快出的强化方式及MR见流空信号是眼眶SFT的特征性影像学表现.     

Characteristics of primary giant cell tumor in soft tissue on magnetic resonance imaging: A case report

BACKGROUNDPrimary soft tissue giant cell tumor (GCT-ST) is rare and has relatively low malignant potential. Most reports are pathological and clinical studies, while imaging studies have only been reported in cases of adjacent bone or with atypical cystic degeneration. With regard to the findings on magnetic resonance imaging (MRI) or ultrasonography, superficial masses can be further identified based on facial edema, skin thickening, skin contact, internal hemorrhage or necrosis and lobulation of the mass. Unlike deep-seated masses, MRI features do not always provide an accurate diagnosis for benign and malignant patients with superficial soft-tissue lesions. Thus, the application of diffusion-weighted imaging (DWI) to evaluate superficial soft tissue tumors is necessary.CASE SUMMARYA 36-year-old woman who had a suspected malignant tumor in the upper limb on ultrasound and computed tomography is reported. The signal intensity of the suspected tumor was heterogeneous on plain MRI; nodular and heterogeneous enhancement was observed in the tumor with irregular shapes and blurred margins on dynamic contrast-enhanced MRI. The lesion on DWI was hyperintense with a higher mean apparent diffusion coefficient (ADC) value. Finally, a GCT-ST was confirmed by pathology. This case suggests that GCT-ST should be distinguished as a benign soft tissue mass from giant cell-rich soft tissue neoplasms or malignant tumors.CONCLUSIONThe MRI features of the superficial GCT-ST in the upper limb included heterogeneous signal intensity within the lesion on T2-weighted image (T2WI) and T1-weighted fat-saturation spoiled gradient recalled echo (T1 FSPGR), nodular enhancement with blurred margins, irregular shapes, and a slow-increased enhancement. DWI could be used to differentiate a benign soft tissue mass from a malignant mass by the mean ADC value and provide more radiologic-pathologic information for the diagnosis of GCT-ST. Comprehensive imaging of primary GCT-ST could help complete tumor resection, and in turn likely prolong survival after surgery.     

肾上腺神经鞘瘤的CT和MR表现

目的 探讨肾上腺神经鞘瘤的CT和MR表现。方法 回顾性分析12例经手术病理证实的肾上腺神经鞘瘤的临床及影像学资料,所有患者接受CT平扫及增强扫描,4例接受MR平扫及增强扫描。结果 12例肾上腺神经鞘瘤均单发,其中左侧8例,右侧4例,肿瘤体积1.75 cm×1.64 cm×2.91 cm~12.56 cm×9.63 cm×25.26 cm,CT平扫8例为均匀等密度或略低密度,4例密度不均,内有坏死、囊变,其中1例伴少许钙化,平均CT值15~40 HU,增强后呈轻至明显强化,实质部分强化均匀,囊性部分无强化。MR平扫示肿瘤在T1WI表现为等或低信号,T2WI为稍高信号,1例肿瘤信号均匀,增强扫描明显均匀强化;3例由于坏死、囊性变信号不均。结论 CT和MRI显示肾上腺区病变具有完整包膜、内部囊性变、出血、钙化及渐进式强化等为肾上腺神经鞘瘤主要影像学特征,可提示肾上腺神经鞘瘤诊断、并为临床诊治提供重要信息。