18F-NaF PET/CT骨显像在甲状旁腺功能亢进性骨病中的应用

目的 探讨甲状旁腺功能亢进性骨病18F-NaF PET/CT骨显像的影像学特点及其应用价值。 方法 收集30例经临床及术后病理证实为甲状旁腺功能亢进症患者[男性11例、女性19例,年龄18～71（52.3±13.5）岁]的18F-NaF PET/CT骨显像及99Tcm -亚甲基二膦酸盐（99Tcm-MDP）全身骨显像资料,回顾性分析其18F-NaF PET/CT骨显像特点,对比两种骨显像方法对该病局部骨骼病灶的检出情况,并根据Mirels评分标准对棕色瘤进行评分。 结果 两种骨显像方法定性结果一致,即骨显像阴性15例,阳性15例。甲状旁腺功能亢进性骨病在18F-NaF PET图像上大部分表现为以全身多骨弥漫性骨代谢增高为主的多种代谢性骨病征象,并发棕色瘤、骨硬化及病理性骨折等时表现为单发或多发局灶性显像剂异常分布,其中棕色瘤表现为局灶性显像剂浓聚、显像剂稀疏或病灶中心显像剂分布缺损伴边缘显像剂不均匀浓聚;同机CT图像上均表现为全身多骨多种形式的骨质吸收,其中,表现为广泛骨质疏松13例、伴棕色瘤7例、骨质硬化6例、骨质软化3例、病理性骨折3例。15例甲状旁腺功能亢进性骨病患者共检出局部骨骼病灶（棕色瘤、骨硬化、病理性骨折、假骨折）53个,其中,18F-NaF PET/CT骨显像全部检出,99Tcm-MDP全身骨显像检出32个。7例甲状旁腺功能亢进性骨病患者伴棕色瘤,位于长骨的棕色瘤病灶数共24个,其中9个Mirels评分大于9分。 结论 甲状旁腺功能亢进性骨病在18F-NaF PET/CT骨显像上的全身骨代谢及解剖学表现有一定的特征性表现,18F-NaF PET/CT骨显像结合同机CT上全身骨骼病灶的详细信息,在甲状旁腺功能亢进性骨病的诊断、鉴别诊断及病情严重程度评估中有更好的应用价值。     

Evaluating the perfusion of occupying lesions of kidney and bladder with contrast-enhanced ultrasound

PurposeTo evaluate the clinical diagnostic value of contrast-enhanced ultrasound (CEUS) for occupying lesions of kidney and bladder.Materials and MethodsCEUS was performed for a total of 50 kidney and bladder occupying lesions in 47 cases, and CEUS manifestations of these lesions were observed and analyzed. Patterns of dynamic changes in perfusion phases of CEUS were summarized and compared with results of postoperative pathology, enhanced computed tomography (CT), magnetic resonance imaging (MRI), and follow-ups.ResultsCEUS results showed that there were 22 cases of malignant renal tumors, 11 cases of benign lesions, two cases of renal column hypertrophy, and 12 cases of malignant bladder tumors (15 lesions). Renal cell carcinoma exhibited various CEUS manifestation, with the majority showing fast filling and hyper-enhancement. CEUS manifestation of renal hamartoma was characterized by slow filling and slow outflow. Renal cystic lesions always exhibited no enhancement within the cysts. Renal column hypertrophy exhibited the same enhancement pattern as the renal cortex. CEUS manifestation of bladder carcinoma was mainly characterized by quick filling, quick outflow, and hyperenhancement.ConclusionsCEUS offers real-time observation of perfusion in occupying lesions of kidney and bladder, but the enhancement pattern of kidney occupying lesions was complex; therefore, combination of enhanced CT, MRI, and CEUS may be necessary.     

Bone abnormalities of the knee: prevalence and significance at MR imaging

Focal abnormal signal intensity within the distal femoral condyles or proximal tibial plateaus is frequently seen on T1- or intermediate-weighted magnetic resonance (MR) images of the knee. To characterize the prevalence and significance of these findings better, a retrospective study of MR imaging of the knee, performed on the first 434 consecutive patients at a primarily outpatient community MR imaging center, was undertaken. A signal intensity loss demonstrated on images with a short echo time (20 or 25 msec) was divided into three types based on morphologic criteria. A type 1 finding was a diffuse, often reticulated signal intensity loss in the metaphyseal and epiphyseal regions of bone. A type 2 loss was associated with an interruption in the smooth, black cortical line. A type 3 finding was a profound signal intensity loss primarily restricted to the immediate subcortical region. Seventeen percent of all cases revealed a type 1 or 2 loss that may have been compatible with acute bone injuries. These bone lesions were frequently associated with tears of the anterior cruciate ligament and contralateral collateral ligament, but infrequently these lesions were detected with plain radiography and arthroscopy. When associated with a weight-bearing cortex, bone injuries detected with MR imaging may explain clinical symptoms of pain on weight bearing, and type 1 injuries may represent regions of bone at increased risk for the subsequent development of insufficiency fractures if the bone is not adequately protected during trabecular healing.     

Gamma camera renography with 99Tcm-MDP and 131I-Hippuran

Nineteen patients with urologic disorders referred to bone scintigraphy were evaluated with a dual radioisotope technique using simultaneous injection of 99Tcm-MDP and 131I-Hippuran. The MDP and Hippuran renograms showed in general the same pattern and there was no difference between the kidney function determined with the two radionuclides. The peak of the MDP curves occurred later and was less distinct than that of the Hippuran curves. The residual activity of the kidneys 20 min after the injection was higher on the MDP renograms compared with the Hippuran renograms. The early sequential MDP images were superior in quality to the Hippuran images and to the renal images obtained at bone scintigraphy. The early MDP images correlated well with the findings at urography performed in 12 patients, as all cases of radiologically diagnosed hydronephrosis, reduction of renal parenchyma and renal mass lesions became demonstrated. Renal calculi were only diagnosed at urography. In conclusion, MDP cannot replace Hippuran as a renal radionuclide agent, mainly due to its lower extraction ratio and the high bone uptake. However, an increased use of early dynamic renal imaging is recommended in urologic patients referred to bone scintigraphy as valuable information about renal function may be obtained by this procedure.     

MR imaging of bone metastasis]

One hundred and three patients with known malignancy and suspected bone metastasis underwent magnetic resonance imaging. In 93%, the metastatic lesions, detected both on plain films and radionuclide bone scans, showed decreased signal intensity on T1-weighted images and increased signal intensity on T2-weighted images. All lesions, except one lesion showing much blastic change on plain films, showed contrast enhancement with Gd-DTPA administration. Although further investigation is needed, a correlation between the type of primary malignancy and the signal intensity of the metastatic lesion is suggested. Among 312 metastatic lesions detected by MR imaging, 272 lesions (87%) and 134 lesions (40%) were also detected by radionuclide bone scans and plain films, respectively. In five cases, MR imaging clearly revealed the lesion compressing the spinal cord, which helped us formulate a therapeutic plan. We conclude that MR imaging is the most sensitive examination for detecting bone metastasis and is necessary for planning treatment.     

非典型肾血管平滑肌脂肪瘤的影像诊断

目的分析肾脏无或少脂肪血管平滑肌脂肪瘤的影象学表现,探讨CT和MRI在其鉴别诊断中的价值。方法回顾分析13例经手术病理证实的非典型肾血管平滑肌脂肪瘤的影象学表现,所有病例均做CT检查,其中6例做MRI检查。结果肾血管平滑肌脂肪瘤13例共15个病灶,其中仅4例含少量脂肪成分,余所有病例均未见明显脂肪成分。CT平扫除4例呈等密度外,余均呈略高密度,动态增强扫描在肾皮质期呈明显均匀强化。MRI显示所有肿瘤在T2WI脂肪抑制时均呈低信号。结论非典型肾血管平滑肌脂肪瘤易与和肾癌相混淆,CT表现具有一定的特征性和鉴别诊断价值,如鉴别诊断仍有困难,应做MRI检查以提供进一步的诊断依据。     

Whole body MRI for detecting metastatic bone tumor: comparison with bone scintigrams.

PURPOSE: To compare the effectiveness of whole body MRI (WB-MRI [magnetic resonance imaging]) and bone scintigram (BS) at detecting bone metastasis. MATERIALS AND METHODS: WB-MRI was performed on 16 patients for detecting bone metastasis (6 breast carcinoma, 7 prostatic carcinoma, 1 renal cell carcinoma [RCC], 1 hepatocellular carcinoma [HCC], and 1 primary unknown). BS was also performed in all cases. Patients were placed on a table top extender (Philips Medical Systems). The maximal longitudinal field of view (FOV) was 200 cm. At first, the total spine was imaged in the sagittal plane with a three-station approach for two image sets (fast spin-echo [SE] T1-weighted images [T1WI] and short tau inversion recovery [STIR] images). The whole body was then imaged in the coronal plane with a seven-station approach for two image sets (fast field echo [FFE] T1WI and STIR). Total examination time, including patient positioning, was within 40 min. Three independent radiologists interpreted the imaging data. RESULTS: WB-MRI identified 5 cases of 24 lesions as bone metastasis, while BS identified 3 cases of 25 lesions. Concordance between WB-MRI and BS was seen in 3 cases of 22 lesions (81%). For two cases of 2 lesions, which were identified only with WB-MRI, the lesions were located in the sacrum and thoracic spine. For one case of 3 lesions, which was identified only with BS, the lesions were located in the skull and rib. CONCLUSION: WB-MRI was an excellent method for screening bone metastasis, especially the vertebral body.     

False-normal bone imaging in spinal tuberculosis

Tc-99m MDP bone imaging in spinal tuberculosis usually shows increased radioactivity at the sites of involvement. Uncommonly, the bone scan can be normal if the infection is low grade, indolent, or severely destructive. Two cases of spinal tuberculosis with normal bone imaging are reported. A normal bone image does not exclude tuberculous spondylitis. If there is clinical suspicion of this disease, further investigations, including tissue specimens, should be obtained.     

CT findings in fire arm injuries of the pelvis. Personal experience

PURPOSE: We investigated the yield of CT in firearms wounds with pelvis involvement by evaluating the CT features of pelvis, bone walls, and associated injuries, if any. CT plays a major role, while conventional radiography remains an important integration in the workup of pelvis bone injuries. MATERIAL AND METHODS: We report a retrospective series of pelvis gunshot wounds studied with CT in a 5-year period; the patients were all men, with a mean age of 38 years (range 18-56). When only the pelvis was involved, CT was performed from the transverse umbilical plane to the pubis, in order to include the continuous abdomen. We used an intravenous contrast agent to study the aorta and its iliac branches, pelvic vessels, active hemorrhagic effusions and bladder filling. RESULTS: Penetrating firearms wounds were found in 21 cases and perforating ones in 7. In the penetrating wounds, the bullet course was most frequently (75%) stopped by the pelvic bones, with retention and CT visualization within muscular and bone structures. The incidence of bone injuries, especially crash wounds, was high, with 18 cases (64%). In both types of wounds with anterior course, we demonstrated bladder perforation in 2 cases, vascular damage in 2 and perforation of intestinal loops in 6. DISCUSSION AND CONCLUSION: Paradoxically, pelvic bone fractures may be "protective" for the pelvic content; however the involvement of large arteries and veins and multiple perforations of intestinal loops are no less dangerous than the upper abdominal wounds. CT is an important diagnostic tool that permits accurate and prompt evaluation of pelvic organs such as intestine, bladder and bone structures. Thus, CT permits prompt assessment of pelvic structures involvement by firearms wounds, which provides the clinician with useful imaging findings of bullet damage.     

原发性骨恶性纤维组织细胞瘤的CT和MRI诊断

目的:探讨原发性骨恶性纤维组织细胞瘤(BMFH)的CT和MRI表现,以提高影像诊断水平。方法:收集经手术病理证实的原发性BMFH 13例,9例行CT检查,其中行增强扫描3例;6例行MRI检查,其中行增强扫描2例;2例同时行CT和MRI检查。分析原发性BMFH的CT和MRI表现,并与组织病理学表现相对照。结果:13例中,长骨骨端11例,长骨骨干1例,髂骨1例。骨质表现为溶骨性破坏,其中6例病灶边缘有轻度骨硬化,7例骨质破坏区间夹杂粗细不等的骨嵴,骨膜反应1例;MRI表现为T1WI等低信号,T2WI混杂高信号。13例均见超过骨破坏范围的软组织肿块,钙化1例;T1WI表现为等或等低信号,T2WI为等高或混杂高信号。CT、MRI增强扫描病变不均匀强化。结论:原发性BMFH的CT、MRI表现有一定的特征,能较好地反映病变的病理特点,对术前明确诊断具有重要意义。     

Bladder candidosis after renal transplantation: contribution of ultrasonography

Candidosis of the ureter and the bladder is an infrequent complication after renal transplantation. A case occurring early after kidney transplantation is reported in a patient presenting with candiduria. Ultrasound examination detected several fungal bezoars, presenting as a proliferating, avascular lesions, located within the ureter and the bladder. It allowed to demonstrate the rapid extension of lesions, in spite of a medical treatment, leading to a successful endoscopic removal of fungus balls.     

Clinical use of urinary tract magnetic resonance imaging

MR imaging should not be used to evaluate the majority of the lesions described herein but should be reserved for specific clinical situations. The detection and differential diagnosis of adrenal masses is a legitimate application of this technique. The staging of renal tumors in patients in whom CT fails to do so may be accomplished by MR imaging. Establishment of patency of the renal veins and of surgical shunts involving these veins may be performed by MR imaging if Doppler ultrasonography proves unsatisfactory. MR imaging may differentiate between stable retroperitoneal fibrosis and malignant disease in patients in whom this differential is a problem. Hematomas may be distinguished from nonhemorrhagic fluid collections anywhere in the abdomen or pelvis. In selected patients, the local extent of certain bladder tumors may be evaluated by MR imaging when CT and biopsy fail to do so. In testicular disease, MR imaging may aid in the differential diagnosis of abnormalities that are not sufficiently characterized by ultrasonography, and MR imaging may detect undescended testes in some patients in whom ultrasonography fails to do so. In the future, wider application of fast scanning with bolus administration of soluble paramagnetic contrast agents may refine the differential diagnosis of adrenal masses and aid in the detection of renal masses. MR angiographic techniques ultimately may constitute a screening procedure for renal arteriostenosis. A subset of patients with prostate carcinoma may prove to benefit from local staging of the disease by MR imaging.     

Secondary foci of primary tumors of the bladder in the upper urinary tract

In 10 years the authors have observed 16 cases of upper urinary tract tumors, appearing from 2 to 16 years after the initial diagnosis of bladder carcinoma. Such lesions are more frequent than has been suggested in the literature and represent 25% of all tumors of the renal pelvis and ureter seen in our service during this period. We have shown vesicoureteral reflux directly in 6 cases, indirectly in a further 6 with suggestive signs in 3 more. We believe that reflux causing the implantation of desquamated tumor cells from the bladder tumor is the most important pathogenetic mechanism for upper urinary tract “recurrences.” The interval between the initial diagnosis of bladder tumor and the appearance of secondary foci may be longer than 20 years. Prolonged surveillance is therefore necessary, particularly if vesicoureteral reflux has been shown.     

Fusion images of Tl-201 SPECT and FDG PET with CT in detection of cervical carcinoma with bladder invasion

Thallium-201 single-photon emission computed tomography (Tl-201 SPECT) and F-18 fluorodeoxyglucose positron emission tomography (FDG PET) are accurate and excellent methods for detecting malignant tumors and related metabolic abnormalities. However, there are still some limitations in clinical application. The major limitation of SPECT is poor image resolution. PET is less sensitive for detecting lesions of the urinary system adjacent to the bladder because of bladder radioactivity. Both T1-201 and F-18 FDG PET often provide less information than x-ray computed tomography (CT) about the anatomic landmarks needed to precisely locate lesions. Recent development of multimodality image registration and fusion has been shown to be an excellent tool to resolve these drawbacks. The authors present a rare case of residual cervical carcinoma with bladder invasion, which was detected by fusion imaging of Tl-201 SPECT and FDG PET with CT. This noninvasive image technique may become a valuable alternative to identify bladder invasion in cervical cancer.     

Successful visualization of cortical malignant lesions on renal scintigram using 99mTc-dimercaptosuccinic acid.

The early (dynamic) and late (static) renal images obtained with 99mTc-dimercaptosuccinic acid (DMSA) were utilized to evaluate renal cortical malignant tumors in 30 cases of renal cell carcinoma each of which had been confirmed by operation or autopsy. Early images, performed 20--50 seconds after radionuclide administration, demonstrated abnormal vascular pools in the cortex. A cold area without DMSA uptake was demonstrated on the 2-hour or late images, reflecting a non-functioning renal mass. Lesions demonstrated with combined early and late images showed a good correlation with those demonstrated by renal angiography in 25 out of 27 cases. However, when almost all the renal tumor was replaced by necrotic lesions, the early image did not reveal hypervascularity. When a highly vascular renal tumor extended to the perinephric tissues, the tumor area was sometimes overestimated on the early image. It is almost impossible to diagnose renal cell carcinoma using radionuclide imaging alone. However, 99mTc-DMSA renal studies, using both early and late imaging, have proven to be a useful, noninvasive adjunct in the detection of malignant cortical lesions.     

<Superscript>99m</Superscript>Tc-depreotide scintigraphy of bone lesions in patients with lung cancer

Purpose Scintigraphy with ^99mTc-depreotide, a somatostatin analogue–technetium ligand, has been used for evaluation of various malignant neoplasms, including lung cancer. The diagnosis of bone metastases in patients with lung cancer is not always definitive with current imaging methods. Visualisation of somatostatin receptors (SSTRs) in bone lesions, when the primary tumour exhibits such receptors, could be helpful in characterising them as metastatic. The aim of this study was to assess the value of ^99mTc-depreotide in differentiating between benign and malignant bone lesions in patients with lung cancer.Methods The study population comprised 20 patients (17 males and three females, mean age 63 years) with proven lung cancer in whom bone lesions had been detected by conventional imaging methods. All patients underwent ^99mTc-hydroxydiethylene diphosphonate and ^99mTc-depreotide scintigraphy within 2 weeks. Bone lesions were classified as benign or malignant on the basis of clinical, imaging and/or histological criteria.Results ^99mTc-depreotide uptake in the primary tumour was seen in 19 of the 20 patients. Conventional imaging methods detected 55 bone lesions, 31 of which were classified as malignant. Twenty-eight (90%) of these lesions showed ^99mTc-depreotide uptake, suggesting bone metastases, while three did not. Twenty-four bone lesions were classified as benign by conventional imaging methods, and none of them showed ^99mTc-depreotide uptake. In addition, ^99mTc-depreotide demonstrated extra-osseous lesions in six patients.Conclusion In patients with lung cancer and bone lesions, ^99mTc-depreotide scintigraphy uptake in the bone lesions supports the diagnosis of malignancy, in particular if the primary lung tumour also exhibits SSTRs. Furthermore, whole-body ^99mTc-depreotide scintigraphy may disclose extra-osseous disease.     

Intraosseous hibernoma: characterization of five cases and literature review

Objective

To describe the imaging and histopathological findings and provide an overview of a recently described and rare cause of bone sclerosis.

Materials and methods

Five cases of intra-osseous hibernoma of bone that presented over the last year. The imaging and histopathology is reviewed.

Results

All cases were identified in asymptomatic middle-aged to elderly adults as incidental findings with bone sclerosis in the axial skeleton. MRI showed lesions that were T1 hypointense to subcutaneous fat and hyperintense to skeletal muscle and one showed contrast enhancement. Glucose avidity was demonstrated on FDGPET in both cases tested and isotope bone scan performed in three cases showed strong positivity in two, but uptake was inconspicuous in one case.

Conclusions

Intra-osseous hibernoma is a rare cause of sclerotic bone lesions, predominating in the axial skeleton of middle-aged and elderly adults. They have a non-aggressive appearance on CT and on MRI are T1 hypointense to subcutaneous fat and hyperintense to skeletal muscle. They are usually T2 hyperintense and may show peripheral contrast enhancement. They may show increased glucose avidity on FDGPET and may or may not be positive on isotope bone scans. We suspect that with ever-increasing use of a variety of imaging techniques, particularly in a setting of staging for malignant disease, more such cases will come to light. This diagnosis should be added to the differential diagnosis of sclerotic bone lesions.     

浸润性肾盂癌 MRI 诊断价值

目的：分析并评价浸润性肾盂癌的 MRI 影像学特征,以提高对其诊断与鉴别诊断的能力。方法回顾性分析病理证实为浸润性肾盂癌的21例患者资料,所有患者均接受 MRI 平扫及 DWI 检查,其中3例进行 PWI 检查。结果21例浸润性肾盂癌中心均位于肾脏集合系统,肾脏轮廓大多无明显变化。病灶在 MRI 平扫上大多呈稍长 T1稍短 T2信号,5例病灶呈混杂 T1混杂 T2信号,病灶在 DWI 均呈高信号。3例行 PWI 扫描呈轻-中度强化。3例行肾 AMRA 检查显示肾动脉受包绕推挤,4例伴有静脉癌栓形成,11例伴有腹膜后淋巴结转移,3例伴有肾上腺转移。1例伴有输尿管尿路上皮癌,2例伴有膀胱癌。结论MRI 具有多参数成像能力及较高的软组织分辨率,可清晰显示病灶部位及周围关系,对浸润性肾盂癌诊断及鉴别诊断具有较高的价值。     

儿童恶性肿瘤股骨转移的骨显像和MRI比较

目的比较骨显像和MRI在儿童恶性肿瘤股骨转移中的应用价值.方法对经病理检查确诊的25例恶性肿瘤患儿（神经母细胞瘤12例,淋巴瘤8例,原始神经外胚层肿瘤2例,横纹肌肉瘤3例）分别行全身骨显像和双侧股骨MRI,MRI采用自旋回波T1WI及短时反转恢复（STIR）序列冠状面成像.结果12例神经母细胞瘤患儿中骨显像阳性7例,可疑2例,阴性3例,7例阳性、2例可疑及1例阴性病例MRI检查均阳性;8例淋巴瘤骨显像阳性5例,阴性3例,5例阳性及2例阴性患儿MRI阳性;2例原始神经外胚层肿瘤骨显像与MRI均阳性;3例横纹肌肉瘤骨显像阳性2例,阴性1例,MRI均阳性.此外,MRI发现股骨的异常信号范围大于骨显像.结论在儿童恶性肿瘤骨转移中联合应用骨显像和MRI有助于尽早诊断及提高诊断准确性.     

Lumbosacral osseous tumors in children

A wide variety of benign and malignant neoplasms in children involve the lumbosacral region. When a solitary lesion of the lower spine occurs, tumors or tumor-like lesions represent an important group of entities for diagnostic consideration. Diagnostic investigation should begin with a patient history, physical examination, laboratory testing, and radiography. Roentgenograms, which demonstrate bone deviations, should be used as an initial examination. The results should direct further imaging studies, such as computed tomography (CT), magnetic resonance imaging (MRI), and bone scintigraphy. CT should be the chosen modality for delineating tumoral osteoid matrix formation. MRI shows soft-tissue masses and medullary infiltration better than any other radiological modality. A multimodal radiological approach is helpful in the overall evaluation and differential diagnosis of vertebral lesions in children. Although imaging features, especially of benign lesions, may yield a high percentage of accurate diagnoses, in cases with radiological findings highly suggestive of malignancy, a specific diagnosis cannot always be made, and histopathological findings are essential to achieve the diagnosis that will guide the therapy.