FDG-PET is able to detect pancreatic carcinoma in chronic pancreatitis

Purpose 2-(¹⁸F)-Fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is an imaging technique which enables detection of malignancies. FDG-PET has been established as a tool for the diagnosis of pancreatic carcinoma (CA). Early detection is mandatory as cure can only be achieved in non-advanced disease. This is, however, very difficult with conventional radiological techniques. Patients with chronic pancreatitis (CP) are at risk of developing CA. A simple, reliable screening method for malignant degeneration is highly desirable. We set out to investigate whether FDG-PET is able to detect CA in the setting of CP and can fulfil a potential role in the early detection of CA in CP.Methods FDG-PET was performed in 77 CP patients and in six patients with CP complicated by CA (CP + CA). We included 26 CA patients as a positive control. A positive scan was defined as focal FDG accumulation in the pancreas region.Results In 67 of the 77 CP (87%) patients, pancreatic FDG accumulation was absent. Six patients had significant accumulation. In CA, 24/26 patients had a positive PET. Five out of the six patients with CP + CA had focal uptake, while minor uptake was seen in one patient. FDG-PET was positive in almost all CA patients and CP + CA patients. FDG-PET was negative in the large majority (87%) of CP patients, which suggests that a positive PET scan in CP patients must lead to efforts to exclude a malignancy.Conclusion These data suggest that FDG-PET has a potential role as a diagnostic tool for detecting CA in longstanding CP.     

Contrast-enhanced transabdominal ultrasonography in the diagnosis of pancreatic mass lesions

Purpose:
In this study, we evaluated the diagnostic usefulness of contrast-enhanced transabdominal ultrasonography (CE-US) in pancreatic mass lesions that could be detected by US. Material and Methods:
CE-US was performed in 37 patients with various pancreatic mass lesions to evaluate the characteristic vascular findings. Results:
Pancreatic tubular adenocarcinoma showed negative enhancement pattern in 16 cases and a slight spotty enhancement pattern in 5 cases. Poorly differentiated adenocarcinoma showed slight homogeneous enhancement pattern in 1 case and acinar cell carcinoma was expressed as a heterogeneous enhancement pattern in 3 cases on CE-US. Endocrine cell tumor had a strong homogeneous enhancement pattern in 3 cases, a strong central enhancement in 1 case and a strong peripheral enhancement in 2 cases. Pseudotumorous pancreatitis showed an iso-enhancement pattern in 6 cases. Conclusion:
CE-US is useful in evaluating the vascularity of the lesions in various pancreatic mass lesions in real-time images, and may be useful for the differential diagnosis of pancreatic mass lesions.     

Phase-inversion tissue harmonic imaging compared with conventional B-mode ultrasound in the evaluation of pancreatic lesions

The aim of this study was to compare the diagnostic sensitivity, specificity, and image quality of conventional B-mode US (BM) and phase-inversion tissue harmonic imaging (PTHI) regarding pancreatic pathology. In a prospective study, 107 patients, aged between 28 and 85 years, underwent US examinations of the pancreas with both BM and PTHI in a randomly chosen order. As diagnostic reference, either contrast-enhanced CT or MRI examinations of the upper abdomen were obtained in all patients. Sensitivity and specificity were evaluated using the Students t test. Differences in overall image quality, lesion conspicuity, fluid–solid differentiation, and delineation of the pancreatic tail were analyzed using Wilcoxons signed ranks test and Bowkers symmetry test. Sixteen of 107 examined patients (15%) were non-diagnostic and excluded due to technical limitations such as abdominal gas. A total of 60 pancreatic lesions (cysts, acute pancreatitis, dilatation of the pancreatic duct, calcifications, and solid tumors) were diagnosed by CT or MRI. Phase-inversion tissue harmonic imaging had a higher sensitivity of 70% (14 of 20) than BM (60%; 24 of 40) for the detection of pancreatic lesions; however, the difference was not statistically significant (p=0.46). In the assessment of lesions <1 cm of size, PTHI had a sensitivity of 70% and BM 46.7%, whereby the difference again was not statistically significant. Phase-inversion tissue harmonic imaging proved to be superior to BM regarding overall image quality (p<0.0001), lesion conspicuity (p=0.0045), and fluid–solid differentiation (p=0.0002), as well as the delineation of the pancreatic tail (p<0.0001). These differences were statistically significant. The statistically significant improvement of image quality with regards to lesion conspicuity, fluid–solid differentiation, and delineation of the pancreatic tail favors the use of PTHI when evaluating the pancreas with US. Sensitivity for pancreatic lesions is increased with PTHI in comparison with conventional sonography (BM), especially in lesions <1 cm in diameter, although the difference was not statistically significant.     

A special case on the use of ultrasonography for evaluation of the spinal canal and its contents in adults

In this article we present a 70-year-old man with a history of severe trauma in the upper thoracic spine. This patient presented at our emergency department with a leaking wound in the lower neck after removal of osteosynthetic material. He had undergone a laminectomy of the third thoracic vertebra in the past. As an incidental finding, while examining the region of the lower neck by transcutaneous ultrasonography, we diagnosed a post-traumatic syrinx of the spinal medulla at this level.     

青年胰腺肿瘤16例临床诊治体会

目的探讨青年胰腺肿瘤的临床特点,以提高青年胰腺肿瘤的早期诊断率和治疗效果。方法分析16例青年胰腺肿瘤的临床表现,影像学检查结果,实验室检查结果,临床病理,治疗方法。结果青年胰腺肿瘤首发主要表现为上腹饱胀不适,上腹痛或背部疼;病理类型以腺癌多见;辅助影像学检查中,B超符合率75.0%,CT符合率92.0%,MRI符合率83.0%;根治性手术率为37.5%。患者预后差,5年生存率31.3%。结论青年胰腺肿瘤根治性手术率低,预后差,生存时间较短,应重视青年胰腺肿瘤的临床早期诊断。     

The ability of67ga scintigraphy to detect the lesions ofEchinococcus multilocularis infection: Preliminary results

AIM: To assess the ability of 67Ga scintigraphy to detect the lesions of Echinococcus multilocularis (EM) infection. MATERIALS AND METHODS: An animal model of EM infection was developed. The infected tissues taken from stock infection were placed into the abdominal cavity of uninfected animals operatively. The success of implantation was controlled 20-25 days after implantation. Five infected and 2 healthy animals were studied. All of the animals were examined by ultrasound before the scintigraphic evaluation. After the injection of 7.4 MBq (200 microCi) 67Ga citrate intravenously, static images from the whole anterior thorax and abdomen were obtained at 24, 48 and 72 hours. Visual and semiquantitative analyses were performed. In semiquantitative analysis, an irregular region of interest was drawn over the thorax as the background, excluding the heart and a second region of interest was drawn over the abdomen, excluding the liver and spleen. Abdomen/ background ratios were calculated using the mean counts. RESULTS: In the visual evaluation, it was noticed that there was considerably increased 67Ga uptake in the abdomens of the infected animals. In infected animals, mean abdomen/background ratios at 48 and 72 hours (3.76 +/- 1.04, 4.13 +/- 0.72, respectively) were increased compared with mean abdomen/background ratios at 24 hours (2.94 +/- 0.77). These increases in abdomen/background ratios were statistically significant at 72 hours (p = 0.04). Between the infected animals and control group, mean abdomen/background ratios were compared, and statistically significant differences were found in the images obtained at 48 and 72 hours. CONCLUSION: Imaging at 72 hours seems to be more suitable imaging time for the diagnosis of alveolar echinococcosis. 67Ga scintigraphy may successfully demonstrate the lesions of EM infection localized intraperitoneally. The method of 67Ga scintigraphy is useful because it is simple, non-invasive and relatively safe.     

DCE-MRI药代动力学参数预估胰腺癌增殖及侵袭转移的可行性初探

目的 探讨DCE-MRI药代动力学参数无创评估胰腺癌Ki67、MMP14表达状况,进而探讨其预估胰腺癌增殖及侵袭转移的可行性.方法 前瞻性连续收集经病理证实的胰腺癌患者21例,术前行胰腺DCE-MRI扫描并测量癌灶的药代动力学参数Ktrans、Kep、Ve和Vp.采用独立样本T检验分别比较Ki67、MMP14高、低表达...     

Complete transection of the pancreas due to a single stamping injury: a case report

Complete transection of the pancreas due to a single stamping injury is reported. A 47-year-old female was stamped on in the epigastric region by her common-law husband when lying on her back. Immediately after the stamping, she complained of severe abdominal pain. In an emergency hospital, the abdominal CT (computed tomography) scan showed a large haematoma around the pancreas head. In the surgical operation that followed, a complete transection of the pancreas between the head and body was unexpectedly discovered. Furthermore, severe traumatic changes were found in the liver, mesentery, splenic artery and vein. The medico-legal autopsy revealed marked haemorrhaging in the abdominal subcutaneous adipose tissue and rectus muscle in the epigastric region. The external blunt force that acted on the abdomen had forcibly compressed the pancreas against the spinal column. Blunt pancreatic injury is relatively uncommon, but pancreatic injuries should always be considered in patients or autopsy cases after external blunt force to the abdomen. Received: 17 July 2000 / Accepted: 7 January 2001     

术前预测胰腺癌分化程度的临床-影像组学模型的建立和验证

目的：建立预测胰腺癌分化程度的临床-影像组学模型,并在独立队列中进行验证。方法：收集56例经病理学检查确诊为胰腺癌的患者。基于MaZda将整个病灶作为感兴趣区（region of interest,ROI）,采用软件自带的3种提取方式提取共计30个影像组学特征,并去除重复的特征。然后对影像组学特征进行检测,剔除高共线性特征。依据正态性检验,分别行独立样本t检验和Mann-Whitney U检验。再联合临床指标糖类抗原（carbohydrate antigen,CA）19-9,构建临床-影像组学预测模型。结果：特征Teta2和S(1,0)Entropy在高、中低分化组胰腺癌中存在显著差异,曲线下面积（area under curve,AUC）分别为0.68和0.70。两者联合得到的AUC为0.74。联合肿瘤标志物CA19-9建立的临床-影像组学模型的AUC为0.82,该临床-影像组学模型在验证组中同样获得了较好的诊断效力（AUC为0.78）。结论：联合影像组学特征和临床指标构建的临床-影像组学预测模型可辅助评判胰腺癌分化程度。     

Effect of a delay in commencing imaging on the ability to detect transient thallium defects

Sixty patients, 42 with coronary disease and 18 normals, were studied to assess the impact of a delay following exercise in commencing thallium imaging on the sensitivity for detecting ischemic transient defects. Three sets of images were obtained beginning 2 min, 18 min, and 2 hr after exercise. Each patient's images were separated into two pairs of studies for analysis: 2 min-2 hr and 18 min-2 hr. Of the 42 patients with coronary disease, a greater number had transient defects detected on the 2 min-2 hr compared with the 18 min-2 hr study (22 compared with 14, p less than 0.05). False positives were not increased by earlier imaging. We conclude that a modest (18 min) delay obtaining the first set of images causes a significant reduction in the ability to detect transient thallium defects, and that imaging should begin several minutes after exercise.     

影像技术在胰腺脂肪浸润与2型糖尿病相关性研究中的应用进展

胰腺脂肪浸润与2型糖尿病(T2DM)的发病有相关性,通过测量胰腺的脂肪含量可以评估胰腺的脂肪浸润情况,对T2DM的预防、早期诊断有非常重要的临床意义。相对于组织病理学活检技术,通过影像学方法测量胰腺脂肪含量具有安全、简单、可重复性高等优点。就基于超声、CT及多种MRI脂肪定量技术在胰腺脂肪浸润与T2DM相关性分析中的研究进展予以综述。     

DCE-MRI定量参数预测胰腺癌组织生物学特征的初步研究

目的:探讨DCE-MRI药代动力学参数术前无创性评估胰腺癌组织生物学状况的可行性。方法:21例经病理证实的胰腺癌患者术前均行胰腺DCE-MRI扫描,测量病灶的药代动力学参数K_trans、K_ep、V_e和V_p。采用独立样本t检验比较不同临床及病理状况时各项定量参数的差异。采用ROC曲线评估各项定量参数对胰腺癌不同组织生物学状况的诊断效能。结果:胰头区肿瘤的V_p高于体尾部(P=0.014);最大径>3 cm和Ⅱ~Ⅲ期胰腺癌的K_trans、K_ep分别高于最大径≤3 cm(P=0.036、0.026)及Ⅰ期胰腺癌(P=0.005、0.037);低分化胰腺癌的K_trans、K_ep和V_p均高于中~高分化胰腺癌(P=0.007、0.003和0.036),而V_e低于中~高分化胰腺癌(P<0.001);伴血管侵犯胰腺癌的K_trans、K_ep和V_p均高于不伴血管侵犯者(P=0.007、0.015和0.003);伴淋巴转移胰腺癌的K_trans、K_ep和V_e均高于不伴淋巴转移者(P=0.012、0.028和0.049)。K_trans和K_ep鉴别Ⅱ~Ⅲ期与Ⅰ期胰腺癌的AUC分别为0.931和0.812;K_trans、K_ep、V_e和V_p鉴别低分化与中~高分化胰腺癌的AUC分别为0.829、0.843、0.926和0.750;K_trans、K_ep和V_p评估胰腺癌有无血管侵犯的AUC分别为0.817、0.832和0.875;K_trans、K_ep和V_e评估胰腺癌有无淋巴转移的AUC分别为0.796、0.801和0.755。结论:胰腺癌DCE-MRI药代动力学参数能在术前无创性评估胰腺癌的组织生物学状况,有助于精准诊断及治疗。     

Preliminary study on evaluation of the pancreatic tail observable limit of transabdominal ultrasonography using a position sensor and CT-fusion image

Background and aim

Transabdominal ultrasonography (US) is commonly used for the initial screening of bilio-pancreatic diseases in Asian countries due to its widespread availability, the non-invasiveness and the cost-effectiveness. However, it is considered that US has limits to observe the area, namely the blind area. The observation of the pancreatic tail is particularly difficult. The goal of this study was to examine the pancreatic tail region that cannot be visualized on transverse scanning of the upper abdomen using US with spatial positional information and factors related to visualization, and observation of the tail from the splenic hilum.

Methods

Thirty-nine patients with pancreatic/biliary tract disease underwent CT and US with GPS-like technology and fusion imaging for measurement of the real pancreatic length and the predicted/real unobservable (PU and RU) length of the pancreatic tail. RU from US on transverse scanning and the real pancreatic length were used to determine the unobservable area (UA: RU/the real pancreatic length). Relationships of RU with physical and hematological variables that might influence visualization of the pancreatic tail were investigated.

Results

The real pancreatic length was 160.9 ± 16.4 mm, RU was 41.0 ± 17.8 mm, and UA was 25.3 ± 10.4%. RU was correlated with BMI (R = 0.446, P = 0.004) and waist circumferences (R = 0.354, P = 0.027), and strongly correlated with PU (R = 0.788, P < 0.001). The pancreatic tail was visible from the splenic hilum in 22 (56%) subjects and was completely identified in 13 (33%) subjects.

Conclusions

Combined GPS-like technology with fusion imaging was useful for the objective estimation of the pancreatic blind area.     

First report on the feasibility of a permanently implantable uni-directional planar low dose rate brachytherapy sheet for patients with resectable or borderline resectable pancreatic cancer

BackgroundMargin negative resection in pancreatic cancer remains the only curative option but is challenging, especially with the retroperitoneal margin. Intraoperative radiation therapy (IORT) can improve rates of local control but requires specially designed facilities and equipment. This retrospective review describes initial results of a novel implantable mesh of uni-directional low dose rate (LDR) Pd-103 sources (sheet) used to deliver a focal margin-directed high-dose boost in patients with concern for close or positive margins.MethodsEleven consecutive patients from a single institution with resectable or borderline resectable pancreatic cancer with concern for positive margins were selected for sheet placement and retrospectively reviewed. Procedural outcomes, including the time to implant the device and complications, and clinical outcomes, including survival and patterns of failure, are reported. A dosimetric comparison of the LDR sheet with hypothetical stereotactic body radiotherapy (SBRT) boost is reported.ResultsOne patient had a resectable disease, and 10 patients had a borderline resectable disease and underwent neoadjuvant treatment. Sheet placement added 15 min to procedural time with no procedural or sheet-related complications. At a median follow up of 13 months, 64% (n = 7) of patients are alive and 55% (n = 6) are disease-free. Compared to a hypothetical SBRT boost, the LDR sheet delivered a negligible dose to kidneys, liver, and spinal cord with a 50% reduction in max dose to the small bowel.ConclusionThis is the first report of the use of an implantable uni-directional LDR brachytherapy sheet in patients with resected pancreatic cancer with concern for margin clearance, with no associated toxicity and favorable clinical outcomes.     

Evaluating the dose to the contralateral breast when using a dynamic wedge versus a regular wedge

The incidence of secondary cancers in the contralateral breast after primary breast irradiation is several times higher than the incidence of first time breast cancer. Studies have shown that the scatter radiation to the contralateral breast may play a large part in the induction of secondary breast cancers. Factors that may contribute to the contralateral breast dose may include the use of blocks, the orientation of the field, and wedges. Reports have shown that the use of regular wedges, particularly for the medial tangential field, gives a significantly higher dose to the contralateral breast compared to an open field. This paper compares the peripheral dose outside the field using a regular wedge, a dynamic wedge, and an open field technique. The data collected consisted of measurements taken with patients, solid water and a Rando phantom using a Varian 2300CD linear accelerator. Ion chambers, thermoluminescent dosimeters (TLD), diodes, and films were the primary means for collecting the data. The measurements show that the peripheral dose outside the field using a dynamic wedge is close to that of open fields, and significantly lower than that of regular wedges. This information indicates that when using a medial wedge, a dynamic wedge should be used.     

Outcomes of patients with hepatocellular carcinoma referred for percutaneous radiofrequency ablation at a tertiary center: analysis focused on the feasibility with the use of ultrasonography guidance

Purpose

This study aimed to assess the feasibility of performing ultrasonography (US)-guided percutaneous radiofrequency (RF) ablation on patients with hepatocellular carcinoma (HCC) and identify causes of procedure infeasibility and its predisposing conditions.

Materials and methods

A total of 109 consecutive patients (male:female = 86:23; mean 59.9 years) with 136 HCCs (mean 1.8 cm) who had been referred for planning US were analyzed. We evaluated overall procedure feasibility as well as specific factors relating to feasibility, including inability to visualize the tumor with US and factors relating to safety of the procedure.

Results

The use of percutaneous RF ablation was concluded as infeasible for 45 tumors (33.1%). Reasons for infeasibility included tumor invisibility (n = 32), a high risk of collateral thermal injury (n = 5), absence of a safe electrode path (n = 5) and a combination of factors (n = 3). Among 136 tumors, 36(26.5%) were invisible due to isoechogenicity (n = 16), indiscrimination from surrounding cirrhotic nodules (n = 10) or an unfavorable location (n = 10). Tumor invisibility was significantly attributed to a small tumor size (P < 0.001, risk ratio = 0.823) and the presence of macronodular cirrhosis (P = 0.006, risk ratio = 4.117). Seven patients with invisible tumors were treated with RF ablation after follow-up (n = 4) or with use of adjacent structures as landmarks (n = 3). Ultimately, 65 of 109 patients were treated with percutaneous RF ablation.

Conclusions

US-guided percutaneous RF ablation for HCC was feasible in about two-thirds of candidates. Infeasibility was mostly due to inability to visualize the tumor with US, especially for patients with smaller tumor and macronodular cirrhosis.     

应用4D-CT对非小细胞肺癌由呼吸运动所致肺受量变化的研究

目的 使用4D-CT评估在肺癌的放射治疗中呼吸运动对肺受量的影响。方法 选取本院10例非小细胞肺癌患者。在治疗前行4D-CT扫描定位,每例患者均获取10个呼吸时相的CT图像序列,在最大密度投影(MIP)图像中勾画靶区,在平均密度投影(AIP)图像中制定计划,然后将计划移植到其他时相图像中计算肺受量,评估肺和体内的绝对剂量体积。结果 肺平均剂量受到呼吸运动的影响很大,不同肿瘤位置时其影响差异较大,当肿瘤位于肺内部时,平均剂量与肺体积变化趋势相同,幅度2.18%显著小于肺体积的变化4.49%(t=4.189,P<0.05),当肿瘤位于肺边缘时,肺平均剂量与肺体积变化趋势相反,变化幅度3.76%,小于肺体积的变化4.49%(t=25.007,P<0.05)。呼吸运动对体内V₅、V₁₀和V₂₀影响很小,体内剂量变化幅度相应为0.47%、0.28%、0.17%,均小于肺体积的变化4.49%(t=11.371、11.188、11.377,P<0.05)。肺体积量V₅、V₁₀和V₂₀与肺体积变化趋势相同,幅度分别为2.39%、1.91%、1.80%,均小于肺体积的变化4.49%(t=2.279、2.298、2.485,P<0.05)。结论 肺的平均剂量随呼吸运动变化明显,在制定计划时要更加谨慎评估肺受量。     

Assessing the impact of common forensic presumptive tests on the ability to obtain results using a novel rapid DNA platform

The rise of DNA evidence to the forefront of forensic science has led to high sample numbers being submitted for profiling by investigators to casework laboratories: bottleneck effects are often seen resulting in slow turnaround times and sample backlog. The ParaDNA^® Screening and Intelligence Tests have been designed to guide investigators on the viability of potential sources of DNA allowing them to determine which samples should be sent for full DNA analysis. Both tests are designed to augment the arsenal of available forensic tests for end users and be used concurrently to those commonly available. Therefore, assessing the impact that common forensic tests have on such novel technology is important to measure. The systems were tested against various potential inhibitors to which samples may be exposed as part of the investigative process. Presumptive test agents for biological materials (blood, semen and saliva) and those used as fingerprint enhancement agents were both used. The Screening Test showed a drop in performance following application of aluminium powder and cyanoacrylate (CNA) on fingerprints samples; however this drop in performance was not replicated with high template DNA. No significant effect was observed for any agent using the Intelligence Test. Therefore, both tests stand up well to the chemical agents applied and can be used by investigators with confidence that system performance will be maintained.     

Small hepatic lesions found on single-phase helical CT in patients with malignancy: diagnostic capability of breath-hold, multisection fluid-attenuated inversion-recovery (FLAIR) MR imaging using a half-fourier acquisition single-shot turbo spin-echo (HASTE) sequence

PURPOSE: To evaluate the diagnostic capability of breath-hold, multisection fluid-attenuated inversion-recovery (FLAIR) imaging using a half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence in combination with T2-weighted fast spin-echo (FSE) magnetic resonance (MR) sequences for small hepatic lesions found on CT in patients with malignancy. MATERIALS AND METHODS: This study included 48 patients with extrahepatic malignancy who underwent both CT and MR examinations. There were a total of 112 small hepatic lesions (73 cysts and 39 liver metastases, <2 cm in diameter) that showed low attenuation on enhanced CT. Three radiologists independently reviewed the CT and MR (FLAIR-HASTE and T2-weighted FSE) images and assigned a confidence level to their evaluation (cyst or metastasis) on a five-point scale. RESULTS: All three reviewers were significantly better able (P < 0.05) to differentiate small hepatic cyst from liver metastasis with combined FLAIR-HASTE and T2-weighted FSE images (Az values = 0.997-0.999) than with CT (0.917-0.932). The mean values of sensitivity, specificity, and accuracy were significantly higher (P < 0.001) for T2-weighted FSE with FLAIR-HASTE (96.6%, 96.8%, and 96.7%, respectively) than for CT (76.9%, 61.6%, and 67.3%, respectively). A confident diagnosis was rendered in 12 of 112 lesions (10.7%) on the basis of CT, and this rate increased to 83 of 112 (74.1%) on the basis of T2-weighted FSE and FLAIR-HASTE imaging. CONCLUSION: FLAIR-HASTE is considered to be an effective sequence for differentiating hepatic cysts from liver metastases without the use of a contrast agent. With FLAIR-HASTE one can confidently diagnose small hepatic lesions found on CT in patients with a malignancy.