Adrenal nonhyperfunctioning adenoma and nonadenoma: CT attenuation value as discriminative index

Background When an asymptomatic adrenal mass is incidentally discovered on abdominal CT scans, the distinction between a nonhyperfunctioning adenoma and a nonadenoma would be important.Methods We evaluated the CT findings of 36 adrenal masses (14 nonhyperfunctioning adenomas, 22 nonadenomas) in 34 patients with no evidence of hormonal hypersecretion. CT attenuation values of adrenal masses on CT scans were calculated by setting a circular region of interest as large as possible in the center of each adrenal mass.Results Below 20 HU in CT attenuation values, all adrenal masses, except one case of ganglioneuroma with myxomatous change, were nonhyperfunctioning adenomas. With an arbitrary threshold of 20 HU, the sensitivity of CT attenuation values in distinguishing nonhyperfunctioning adenomas from nonadenomas was 64%, the specificity was 95%, and the accuracy was 83%. When decreasing the threshold to 15 HU, the sensitivity was 64%, the specificity was 100%, and the accuracy was 86%. The CT attenuation value on noncontrast CT was more useful for making this distinction than the size and interior homogeneity.Conclusions Our data suggest that an asymptomatic adrenal mass with homogeneous low attenuation (15 HU) and less than or equal to 4 cm indicates a nonhyperfunctioning adenoma, and no further examinations are necessary. CT attenuation value on non-contrast CT is the most important discriminatory factor.     

超声检查与CT对肾上腺肿瘤的定位与定性诊断价值

目的 探讨超声检查与CT对肾上腺肿瘤的定位及定性诊断价值.方法 回顾性分析我院经手术及病理确诊的80例肾上腺肿瘤患者84个病灶超声检查及CT检查资料,并与手术及病理诊断结果进行比较.其中4例患者2个病灶,其余76例患者肿瘤单发.84个肿瘤包括库欣皮质腺瘤13个,醛固酮皮质腺瘤22个,皮质腺癌7个,无功能皮质腺瘤6个,肾上腺转移癌22个,嗜铬细胞瘤14个.结果 本组84个肾上腺肿瘤超声检查检出78个,CT检出80个,超声检查与CT定位诊断符合率分别为92.9%(78/84)、95.2%(80/84),差异无统计学意义(χ2=0.003,P>0.05);结合检出病灶超声表现、CT表现与患者临床症状、体征及实验室检查结果综合分析判断,最终超声检查及CT定性诊断符合率分别为90.5%(76/84)、88.1%(74/84),差异亦无统计学意义(χ2=0.248,P>0.05).本组超声检查检出的78个肿瘤中,38个肾上腺皮质腺瘤及13个嗜铬细胞瘤超声声像图表现为低、弱或等回声结节与团块,境界清楚,有7个瘤体因伴液化坏死及钙化,内部回声不均匀;7个皮质腺癌及20个肾上腺转移癌表现为低、弱回声结节或团块,形态不规则,境界不清或呈浸润生长,内部回声不均匀,5个瘤体伴液化坏死及钙化.CT检出80个肿瘤中,39个肾上腺皮质腺瘤及13个嗜铬细胞瘤多表现为境界清楚、密度均匀的结节与团块,其中5个瘤体伴液化坏死及钙化密度不均匀;7个皮质腺癌及21个肾上腺转移癌CT表现为形态不规则、边界欠清或不清、密度尚均匀或不均匀的结节与团块;增强扫描13个嗜铬细胞瘤均呈明显不均匀强化,其中1个同时检出大网膜异常强化灶;7个皮质腺癌为中度或明显不均匀强化;其余多为轻-中度强化.结论 超声检查和CT诊断肾上腺肿瘤的符合率均较高,但也都存在不足之处,因此应根据肾上腺肿瘤大小和患者自身情况选择合适的影像学检查方法.超声检查简便易行,且无辐射,可作为肾上腺肿瘤首选检查方法.     

Adrenal imaging

CT provides exquisite anatomic detail of normal and pathologic adrenal glands but little specificity as to the nature of adrenal masses. MR reliably distinguishes non-functioning and hyperfunctioning adenomas (adrenal mass/liver ratio less than 1.2) and pheochromocytomas (adrenal mass liver ratio greater than 2.5). Metastases to the adrenal gland and primary adrenocortical carcinomas lie in the intermediate range (adrenal mass/liver ratio 1.4-2.5). Particularly problematic are masses with ratios in the 1.2-1.4 range since some non-functioning adenomas and some metastases will have similar signal intensities and cannot be distinguished.     

肾上腺髓脂瘤的CT诊断

目的 探讨肾上腺髓脂瘤的ＣＴ诊断。方法 收集手术病理证实的８例肾上腺髓脂瘤ＣＴ检查资料,分析其临床资料和ＣＴ表现。结果 ＣＴ表现为：平扫示肾上腺区脂肪及软组织混杂密度肿块,边界清晰,２０％伴零星点状钙化,增强后肿块周边及内部软组织密度稍增高,脂肪区密度无变化。结论 ＣＴ对肾上腺髓脂瘤具有特殊的诊断价值。     

Adrenal histoplasmosis: clinical presentation and imaging features in nine cases

Background: We describe a retrospective analysis of the clinical presentation and imaging features in nine patients with adrenal histoplasmosis in nonimmunocompromised patients from a nonendemic region.Methods: Clinically, a tuberculosis-like presentation in four patients and a tumor-like presentation in five patients were seen. All patients were seronegative for the human immunodeficiency virus. Ultrasound (US) in all patients, computed tomography (CT) in six, and magnetic resonance imaging (MRI) in three showed suprarenal masses. CT-guided (in five) and US-guided (in four) biopsy and fine-needle aspiration cytology established a definite diagnosis. The work-up for malignancy and tuberculosis was negative.Results: On cross-sectional imaging, eight patients had bilateral adrenal masses and one had a unilateral adrenal mass. Imaging features were variable. All adrenal masses were hypoechoic on US, homogeneous in five, and heterogeneous in four patients. All adrenal masses were hypodense on CT, homogeneous in four, and heterogeneous in two. Heterogeneous enhancement was seen in three, homogeneous enhancement in two, and no enhancement in one patient. MRI in three patients showed that the masses were of variable signal intensity on all pulse sequences.Conclusion: Our case series showed that adrenal histoplasmosis does occur in immunocompetent persons living in areas not endemic for the disease. The imaging features were variable.     

Adrenal and pseudoadrenal masses: CT and US findings

Computed tomography (CT) is currently the imaging modality of choice for assessing the morphology of the adrenal glands in adult patients. Much useful information can be gained using CT in disease processes which primarily involve one or both of the adrenal glands, such as adenomas, as well as in entities which secondarily affect the adrenals, such as pituitary or metastatic disease. The size and configuration of the glands can be readily determined, and masses may be detected. We discuss CT of normal and abnormal adrenal glands with sonographic (US) and pathological correlation, when available. Entities which may mimic adrenal abnormalities are emphasized. Relative advantages of US over CT in the pediatric patient are discussed.     

肾上腺假性囊肿的CT诊断

目的探讨肾上腺假性囊肿的CT表现,以提高诊断的准确率。方法回顾性分析手术病理证实的6例肾上腺假性囊肿的CT表现。结果6例肾上腺假性囊肿2例呈圆形,4例呈椭圆形,平扫囊肿密度均匀,CT值15～35Hu,6例囊内及囊壁均无强化,厚薄均匀,边缘光滑。结论CT是肾上腺假性囊肿定位诊断较为可靠和准确的方法。     

儿童后腹膜肿块CT与B超表现

目的：报告儿童后腹膜肿块常见与不常见的占位性病变的ＣＴ与Ｂ超表现。材料和方法：对３８例儿童后腹膜肿块病变进行临床，ＣＴ与Ｂ超资料的回顾性分析。结果：本组儿童后腹膜肿块共有１１种病变，以肾上腺和后腹膜神经母细胞瘤最常见，畸胎瘤与肾胚胎瘤其次，肾上腺皮质癌与新生儿肾上腺出血较少见。１１种儿童后腹膜肿块的临床，ＣＴ与Ｂ超特点各不相同。结论：结合临床、ＣＴ与Ｂ超特点对大部分儿童后腹膜肿块能作出明确的诊断。     

Imaging of tumours of the adrenal gland

For differentiation of benign and malignant adrenal lesions, sensitivities and specificities of 85-100% can be reached by unenhanced computed tomography (CT)-methods, chemical shift techniques in magnetic resonance imaging (MRI), delayed enhanced CT-techniques, and by evaluation of wash-out curves in contrast enhanced CT or MRI. An increasing number of adrenal lesions that are detected on imaging studies for indications unrelated to the adrenals can be immediately characterized by delayed series nowadays. According to excellent results of CT and MRI in characterization of adrenal masses, the indications for fine needle aspiration biopsy have already regressed as well as complications associated with this invasive technique.     

Analysis of adrenal masses by 18F-FDG positron emission tomography scanning

This study aimed to analyse the characteristics of adrenal masses visible in the computerised tomography (CT) scans which have been also evaluated by 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (18F-FDG PET), and to characterise the features of 18F-FDG PET scans associated with various adrenal endocrine tumours, especially benign functional tumours. 18F-FDG PET scans of 105 patients with adrenal masses on the CT scan were analysed. Positive uptakes in the 18F-FDG PET scans were seen in 60 malignant tumours (54 metastasic lesions, six primary adrenal cancers) and seven benign tumours. The positive predictive value of 18F-FDG PET imaging to characterise an adrenal mass as a malignant tumour was 90%; the corresponding negative predictive value to rule out malignancy was also 90%. Benign adrenal tumours were smaller than that of malignant lesions (p<0.05). The mean standardised uptake value max (SUVmax) of the metastatic lesions [8.4+/-6.5 (microCi/g)/microCi/kg] was significantly higher than that of the benign adrenal tumours [2.4+/-1.2 (microCi/g)/microCi/kg, p<0.001]. Examination of only the primary adrenal lesions revealed that all adrenocortical carcinomas, two of three cases of pheochromocytomas, three of five neuroblastomas and two of four cases of primary aldosteronism showed positive 18F-FDG uptake. In conclusion, for patients presenting adrenal masses with a high probability of malignancy, 18F-FDG PET can be used to differentiate malignant from benign adrenal lesions. However, the 18F-FDG PET uptake did not show an always consistent pattern for endocrine tumours, which was probably due to the variability inherent in 18F-FDG uptake. This study suggests that 18F-FDG PET scanning can offer supporting data to localise and characterise adrenal tumours.     

肾上腺钝性损伤的CT分析

目的：探讨腹部钝性伤所致肾上腺损伤的CT征象。方法：回顾分析15例因腹部钝伤而行CT检查示有肾上腺损伤的资料，其中男性13例，女性2例。9例行CT平扫及增强检查，6例平扫；11例行CT随访。结果：15例肾上腺损伤均为单侧性损伤并伴同侧胸腹部损伤，位于右侧11例（73％），左侧4例，1例伴肾上腺肿瘤。10例CT主要表现为肾上腺区类圆形或卵圆形血肿（67％），3例（20％）表现为伤侧肾上腺增粗，1例（7％）表现为肾上腺区较弥漫的出血，1例原有肾上腺肿瘤存在。10例（67％）肾上腺邻近脂肪内出血呈条束状或局限性密度增高影，3例（20％）后肾周间隙的出血表现为类似膈脚增厚改变。结论：肾上腺损伤右侧远多于左侧，常伴有同侧胸腹腔和腹膜后损伤，肾上腺血肿有时需与肾上腺原发肿瘤相鉴别，鉴别主要方法是随访及增强CT检查。     

外伤性肾上腺血肿的CT表现

目的:探讨外伤性肾上腺血肿的形成机制、CT诊断特征及临床应用价值。材料与方法:回顾分析19例经CT复查证实的外伤性肾上腺血肿CT扫描资料。结果:19例肾上腺血肿均发生在单侧,其中右侧16例、左侧3例。CT表现为肾上腺区域长椭圆形、类圆形肿块影,CT值50～69Hu,大多数血肿密度均匀、边缘清楚,长径2～4cm,长径与肾上腺前后径一致。合并肾上腺周围组织器官损伤15例,远离肾上腺的下腹部、盆腔损伤3例,单纯性右侧肾上腺血肿1例。本组19例均在外伤后5～192天内做了1～4次CT复查,其中11例从血肿中央开始密度减低,5例从血肿边缘开始密度减低,其余3例不具备上述特点。本组病例中只有2例追踪到6个月后复查血肿吸收消失,肾上腺形态逐渐恢复正常。结论:外伤性肾上腺血肿应首选CT检查,CT诊断具有特征性,有别于其它肾上腺占位,可避免不必要的腹部手术探查。     

Adrenal tumors with late enhancement on CT and MRI

Objectives To identify adrenal masses showing gradual persistent enhancement on delayed contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI). Materials and methods Computed tomography or magnetic resonance images of pathologically proven 400 adrenal tumors were retrospectively reviewed over a 10-year period. We included only adrenal tumors showing gradual persistent enhancement on CT and MRI performed at 15 and 5 min, respectively, after contrast material injection. Results Four tumors in four patients (three men and one woman; mean age, 51 years) met the inclusion criteria. These lesions were as follows: two ganglioneuromas, one myelolipoma with infarction, and one angiomyolipoma with minimal fat. All of these tumors showed gradual persistent enhancement, and highest attenuation during delayed contrast-enhanced CT or strongest enhancement during delayed contrast-enhanced MRI. Conclusion The differential diagnosis of adrenal tumors showing gradual persistent enhancement on delayed contrast-enhanced CT and MRI should include ganglioneuroma, myelolipoma with infarction, and angiomyolipoma with minimal fat.     

肾上腺髓性脂肪瘤的CT诊断与鉴别诊断

目的 :分析肾上腺髓性脂肪瘤的典型及不典型CT表现,并探讨其诊断及鉴别诊断要点。方法 :收集2011至2014年本院经手术病理证实的肾上腺髓性脂肪瘤患者26例,术前行CT平扫、增强动脉期(延迟时间30 s)和门脉期(延迟时间70 s)扫描,分析其CT征象并与病理结果对照。结果:26例患者共发现27个病灶,其中22例患者计23个肿块呈类圆形,有完整纤维包膜,内部密度不均匀,可见较多的脂肪密度内混杂少量轻、中度强化的软组织密度影,术前CT诊断为髓性脂肪瘤,诊断准确。另4例患者术前CT误诊,其中2例病灶内未见成熟脂肪成分,1例术前诊断为肾上腺腺瘤,1例诊断为节细胞神经瘤;其余2例中,1例病灶边缘有粗大钙化,诊断为畸胎瘤或错构瘤,另1例体积较大,向肾上腺前下方生长,考虑为腹膜后脂肪肉瘤。结论:肾上腺髓性脂肪瘤的一般CT征象较典型,当肿块体积较大、合并出血或脂肪成分较少时,应与其他肾上腺及肾上腺外肿瘤鉴别。     

肾上腺非霍奇金淋巴瘤的超声影像学表现

目的 探讨肾上腺非霍奇金淋巴瘤的声像图特征。方法 回顾性分析经穿刺活检或手术病理证实的13例肾上腺淋巴瘤的超声声像图特征。结果 13例肾上腺淋巴瘤患者累及双侧6例,单侧7例,共19个病灶,均为非霍奇金淋巴瘤弥漫大B细胞型。肿块大小3.0~14.0 cm,平均(7.99±3.08)cm。18个病灶为低回声,1个表现为杂乱回声。内部回声均匀者10个,不均匀者9个,其中内部可见条索状稍强回声者7个,伴小片状无回声区4个。彩色多普勒示68.42%(13/19)肿块内未见明显血流信号,仅31.58%(6/19)内探及点状血流信号。此外,3个较大病灶不同程度累及同侧肾脏及其周围组织,1个伴下腔静脉栓子形成。结论 肾上腺非霍奇金淋巴瘤超声声像图多表现为边界清楚的规则低回声团块,肿瘤内无明显或仅见少许点状血流信号,但对于内部回声不均匀伴有液化等征象的病灶,不能完全除外淋巴瘤的可能。     

肾上腺皮质癌的CT表现

目的探讨肾上腺皮质癌(ACC)的CT表现以及其与病理组织学的关系。方法回顾性分析7例ACC患者的CT表现和病理资料。结果所有肿瘤均表现为占据肾上腺区的直径>4cm的巨大分叶状肿块,边缘清晰,具有明显的包膜结构,其中1例突破包膜侵犯肾静脉。肿瘤中央存在囊变结构和瘢痕组织,其中5例为星芒状,2为十字形。4例中心存在沙粒样钙化,所有肿瘤内部均有不同程度出血。结论 ACC具有特征性CT表现,与病理相结合有助于确诊。     

肾上腺肿瘤的平扫CT值与磁共振化学位移成像反相位信号丢失程度相关性的研究

目的探讨肾上腺肿瘤的平扫CT值与磁共振化学位移成像(CSI)反相位信号丢失程度的相关性。方法对36例肾上腺肿瘤进行CT平扫及CSI检查。测量H(平扫CT值)及SII(信号强度指数)、ASR(肾上腺-脾脏化学位移比率)、ALR(肾上腺-肝脏化学位移比率)、AMR(肾上腺-肌肉化学位移比率)。分别对腺瘤组和非腺瘤组的H及其他四项参数进行直线相关性分析,并进行直线回归;用t检验,比较腺瘤与非腺瘤组的这五项参数是否具有显著差异。结果腺瘤组SII(Y)与H(X)呈线性相关(r=0.887),直线回归方程为Y=67.74-1.12X,常数及回归系数的95%可信区间分别为(63.00,72.48),(-1.36,-0.89);同样,其他三项参数(ASR、ALR、AMR)与H间也存在线性相关性,相关系数分别为0.875、0.856、0.750。非腺瘤组H与其他四参数间不存在显著的相关性。腺瘤组与非腺瘤组的五项参数的均值均有显著差异。结论肾上腺腺瘤的平扫CT值与CSI反相位信号丢失的程度之间存在显著线性相关性,二者可以相互印证;但非腺瘤的平扫CT值与CSI反相位信号丢失的程度之间无相关性。     

肾上腺骨髓脂肪瘤的CT表现(附五例报告)

本文报告5例经手术、病理证实的肾上腺骨髓脂肪瘤CT表现。肿瘤多见右侧,典型CT表现:(1)边界清晰、锐利、光滑、无包膜;(2)由低密度脂肪与稍高密度纤维间质而产生密度不均;(3)乎扫、增强无明显变化。并讨论了不常见合并症及不典型CT表现的鉴别诊断。     

嗜铬细胞瘤的CT诊断及评价

目的 评估ＣＴ对嗜铬细胞瘤的诊断价值。方法 分析４３例（良性４０例,恶性３例）经病理证实的嗜铬细胞瘤ＣＴ征象并与Ｂ超结果对照。结果 肾上腺区肿瘤３４例,异位瘤９例（２１％）。ＣＴ表现：８１％（３５／４３）肿块直径大于３ｃｍ。肿瘤实质均显著强化,３２例（７４．４％）密度不均匀,常伴有坏死、液化、囊变或钙化。良笥病变边界清晰,恶性病变易侵犯邻近组织。ＣＴ定位率为９３．３％、定性率为８８．４％均高于Ｂ超（Ｐ〈０．０５）。结论 ＣＴ对嗜铬细胞瘤的定位、定性诊断具有较高价值,是主要的影像检查方法。     

肾上腺节细胞神经瘤的多层螺旋CT诊断（附8例报告）

目的：探讨。肾上腺节细胞神经瘤的CT表现特征,以提高此病CT诊断的准确性。方法：回顾性分析8例经病理确诊为节细胞神经瘤的CT表现,并与病理结果对照研究。结果：8例肿瘤边界均清晰,无周围组织和血管侵犯征象。CT平扫呈均匀稍低密度,CT值约18～35HU,其中内有点状钙化者3例（37．5％）。CT增强扫描有轻度强化,CT值约30～45Hu。CT征象符合病理表现。结论：肾上腺节细胞神经瘤有一定的CT表现特点,多层螺旋CT扫描有助于提高。肾上腺节细胞神经瘤诊断的准确性。