MR Guided Laser-Induced Thermotherapy (LITT)of Malignant Liver and Soft Tissue Tumours

Objective: Presentation of MR guided laser-induced thermotherapy (LITT) for percutaneous interstitial thermotherapy of malignant liver tumours and soft tissue lesions.Material and methods:MR-guided LITT is carried out by means of catheter systems that can be implanted percutaneously. CT or open MRI technologies are used as the control method for inserting the catheter. Irrigated application systems are available for LITT.Findings:Percutaneous LITT currently permits local tumour control of 97.2% for localised liver metastases without an extrahepatic manifestation pattern. In a patient population of 729 patients median survival times of 45.0 months for liver metastases, 42.6 months for patients with colorectal liver metastases have been documented. In the treatment of soft tissue tumours in the head and neck and pelvis MRI guided LITT allows an excellent local tumour control rate and reduces clinical symtoms in a palliative manner.Conclusions:Percutaneous MR-guided LITT permits a high level of tumour control in the case of liver metastases and soft tissue tumours smaller or equal to 5 cm and a maximum number of 5 lesions with an improvement of survival data.     

Complications after interventional sonography of focal liver lesions: a 22-year single-center experience.

OBJECTIVE: To analyze the complications of diagnostic and therapeutic sonographically guided interventional procedures of focal liver lesions observed during a 22-year period in a single center. METHODS: Complications of sonographically guided diagnostic and therapeutic procedures on focal liver lesions, observed during a 22-year period in a single center, were reviewed. From 1979 to 2001, 13,222 patients (age range, 7-89 years; mean, 59 years; 8,688 male and 4,534 female) with 13,777 focal liver lesions underwent 16,648 sonographically guided biopsies and 3,035 therapeutic procedures: pyogenic and amebic abscess aspiration, ethanol injection of hydatid liver cysts, and percutaneous ablative treatments (ethanol injection in either multiple or one-shot sessions, radio frequency ablation, and interstitial laser photocoagulation) of primary and secondary liver tumors. RESULTS: The overall mortality was 0.06%. No death or major complication occurred after diagnostic procedures and liver abscess drainage. In the therapeutic group mortality was 0.6%: 1 patient died of anaphylactic shock during treatment of a hydatid cyst; 7 patients died after liver tumor ablation with ethanol injection (6 after one-shot treatments and 1 after multisession treatments). Major complications after liver tumor ablative procedures included 10 cases of acute liver failure, 2 cases of acute tubular necrosis, 2 cases of self-limiting hemoperitoneum, 2 cases of paralytic ileum, 2 abscesses, and 1 case of cholangitis. One case of a biliary cyst fistula and 1 case of intracystic hemorrhage occurred after treatment of hydatid liver cysts. CONCLUSIONS: Sonographically guided diagnostic biopsy of focal liver lesions and liver abscess drainage are safe procedures. In contrast, liver tumor ablation procedures have a low but definite risk of mortality and major complications. Puncture of hydatid cysts must be performed only in institutions that can treat anaphylactic shock.     

超声引导下经皮穿刺射频消融治疗肝癌的临床价值

目的评价超声引导下射频消融(RFA)治疗肝癌的临床应用价值.方法57例肝癌患者,共83个肿瘤结节(直径1.9~6.2cm),采用Lee Veen针(3.5cm/15G十电极),术中定位、穿刺采用超声引导,≤2.0cm结节单点消融,>2.0cm结节采用多点消融,每个肿瘤结节治疗1~3针,每3~6个月CT复查,对新出现的结节再次行RFA治疗.结果 RFA术后3~7d肿瘤完全消融率93.1%(78/83),术后3、6、12、24个月CT检查,肿瘤完全坏死分别为86%、81%、72%、65%,患者存活率分别为96%、91%、84%、67%.结论超声引导下射频消融治疗肝癌具有创伤小、见效快,并可多次进行、患者痛苦小、体质恢复快,无需输血等优点,是治疗肝癌有效和安全的方法之一.     

Image-guidedcryoablation in unresectable or recurrent advanced colorectal cancer: a retrospective study

Purpose: The present study retrospectively analyzed thesafety and efficacy of computed tomography (CT)-guided cryoablationin the treatment ofunresectable or recurrent advanced colorectal cancer, which did not respond well to or experienced progression with radiotherapy or chemotherapy.Materials and Methods: From January 2013 to April 2015, 31 lesions in 27 patients (16 males, 11 females; mean age of 57.2 years) with pelvic unresectableadvanced or recurrent colorectal cancer were included in the study. The tumor diameter was approximately 3.37 ±1.41 cm. The primary tumor included 25 rectal cancers, 1 sigmoid colon adenocarcinoma, and 1 ileocecal mucinous adenocarcinoma. Cryoablation was performed with 17-gauge cryoprobes and monitored by 64-slice spiral CT. Follow-up was carried out by contrast-enhanced magnetic resonance imaging (MRI). The treatment efficacy was evaluated by symptom palliation, decreased carcinoembryonic antigen (CEA) serum level, and tumor response.Results: The cryoablation procedure was well-tolerated in all patients without major complications or procedure-related mortality. Long-term complications included abscess formation (1 patient), skin frostbite and post-sacrum antrum formation (1 patient). Pain relief was satisfactory in patients with perineal pain (P<0.001), and the median time of pain relief was 3.0 months. Complete ablations were obtained in 22 lesions of 18 patients, while 9 lesions in 9 patients underwent incomplete ablation. The median time to local recurrence for lesions with complete ablations was 15.0 months, and that to the progression of tumors with incomplete ablation was 4.0 months.Conclusion: CT-guided cryoablation is a minimally invasive, safe, and effective therapeutic option for unresectableadvanced or recurrent colorectal cancer. The treatment is well-tolerated by patients, and pain relief is achieved rapidly.     

射频消融联合无水酒精局部注射对原发性肝癌的生命质量及预后的影响

目的分析射频消融联合无水酒精局部注射对原发性肝癌的生命质量及预后的影响。方法纳入该院2011年1月-2014年12月射频消融联合无水酒精局部注射治疗的204例原发性肝癌患者进行分析,采用随机数字表法分为对照组104例,治疗组100例,对照组给予超声引导下经皮无水酒精注射治疗,治疗组给予射频消融联合无水酒精局部注射治疗,治疗观察周期为3个月。观察两组治疗前后的肝功能、甲胎蛋白(AFP)的变化;使用欧洲癌症研究与治疗组织生命质量测定量表(EORTC QLQ-C30)评价患者生命质量的改变;观察复发率及生存期,采用Logistic回归分析预后的危险因素。结果治疗前,对照组与治疗组患者丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、总胆红素、清蛋白、AFP水平比较,差异均无统计学意义(P0.05);治疗后,治疗组患者ALT、AST、总胆红素和AFP水平较对照组降低,差异均有统计学意义(P0.05)。治疗前,对照组与治疗组患者EORTC QLQ-C30总体健康情况、躯体功能、社会功能、恶心和呕吐、疼痛、疲倦、失眠、腹泻和食欲减退评分比较,差异均无统计学意义(P0.05);治疗后,治疗组患者EORTC QLQ-C30总体健康情况、躯体功能、社会功能评分较对照组升高,恶心和呕吐、疼痛、疲倦、失眠、腹泻和食欲减退评分较对照组降低,差异均有统计学意义(P0.05)。随访时间截至2015年6月30日,共随访了190例患者,随访率为93.14%,健在的患者有108例,死亡的患者有82例。多因素Logistic回归分析结果显示,发病位置、治疗前ALT、AFP水平、术中输血、手术方式、肿瘤复发与射频消融联合无水酒精局部注射治疗原发性肝癌后预后相关(P0.05)。结论射频消融联合无水酒精局部注射是一种有效的治疗原发性肝癌的方法,原发性肝癌预后与发病位置、治疗前ALT、AFP水平、术中输血、手术方式和肿瘤复发相关。     

Radiofrequency ablation of neuroendocrine liver metastases—the Middlesex experience

Background Current treatment options for neuroendocrine liver metastases are not widely applicable or not that effective. Image-guided thermal ablation offers the possibility of a minimally invasive, albeit palliative, treatment that decreases tumor volume, preserves most of the normal liver, and can be repeated several times. We report our experience with image-guided thermal ablation in 25 patients with unresectable liver metastases.Methods Since 1990 we have treated 189 tumors at 66 treatment sessions in 25 patients (12 female, 13 male; median age, 56 years; age range, 26–78 years). Thirty treatments were performed with a solid-state laser, and 36 treatments were performed with radiofrequency ablation. All but one treatment was performed percutaneously under image guidance. Sixteen patients had metastases from carcinoid primaries, three from gastrinoma, two from insulinoma, and four from miscellaneous causes. Fourteen of 25 had symptoms from hormone secretion.Results Imaging follow-up was available in 19 patients at a median of 21 months (range, 4–75 months). There was a complete response in six patients, a partial response in seven, and stable disease in one; hence, tumor load was controlled in 14 of 19 patients (74%). Relief of hormone-related symptoms was achieved in nine of 14 patients (69%). The median survival period from the diagnosis of liver metastases was 53 months. One patient with end-stage cardiac disease died after a carcinoid crisis. There were eight (12%) complications: five local and three distant, four major and four minor.Conclusions As a minimally invasive, readily repeatable procedure that can be used to ablate small tumors, preferably before patients become severely symptomatic, radiofrequency ablation can provide effective control of liver tumor volume in most patients over many years.     

The types and frequencies of improved nonmuskuloskeletal symptoms reported after chiropractic spinal manipulative therapy

Objective: To investigate the frequency and types of improved nonmuskuloskeletal symptoms reported after chiropractic spinal manipulative therapy. Design: Retrospective information obtained by chiropractors through standardized interview of patients on return visit within 2 weeks of previous treatment. Setting: The private practice of 87 Swedish chiropractors (response rate 81%). Subjects: Twenty consecutive (presumably naïve) patients per chiropractor (1504 valid questionnaires returned, 86% of optimal number of replies). Intervention: Spinal manipulation with or without additional therapy provided by chiropractors. Main Outcome Measures: Self-reported improved nonmuskulo-skeletal symptoms (reactions). Results: At least 1 reaction was reported after the previous treatment in 21% to 25% of cases. Of these responses, 26% were related to the airway passages (usually reported as “easier to breathe”), 25% were related to the digestive system (mostly reported as “improved function”), 14% were classified under eyes/vision (usually reported as “improved vision”), and 14% under heart/circulation (about half of these reported as “improved circulation”). The number of spinal areas treated was positively associated with the number of reactions. Conclusion: A minority of chiropractic patients report having positive nonmuskuloskeletal reactions after spinal manipulative therapy but such reports cluster predominantly around specific symptoms. It would be interesting to find out if these can be verified objectively and, if so, to investigate if they are caused by the treatment or if they are signs of natural variations in human physiology. (J Manipulative Physiol Ther 1999; 22:559–64)     

Interstitial laser therapy of liver tumors

Purpose: To evaluate MR-guided interstitial laser-induced thermotherapy (LITT) for the treatment of liver tumors.Materials and methods: To date, 1,632 patients with malignant liver metastases have been treated with LITT at our institute. A total of 10,310 laser applications were performed to treat 5,297 lesions.Results: MR-guided LITT achieves a reliable local tumor control and allows an improved survival in patients with primary and secondary liver tumors.Conclusion: MR-guided LITT is a safe method for the treatment of liver tumors and yields an acceptably low rate of major and minor complications due to its minimal invasive character.

Zusammenfassung

Interstitielle Lasertherapie von Lebertumoren Zielsetzung: Evaluation der MR-gestützten laserinduzierten Thermotherapie (LITT) zur Behandlung von Lebertumoren.Material und Methoden: Bis zum heutigen Tag wurden an unserem Institut 1632 Patienten mit malignen Lebermetastasen mit LITT behandelt. Insgesamt wurden 10,310 Applikationen zur Behandlung von 5297 Läsionen durchgeführt.Ergebnisse: Die MR-gestützte LITT erlaubt derzeit eine verläßliche lokale Tumorkontrolle, und eine verbesserte Überlebensrate bei Patienten mit primären und sekundären Lebertumoren kann erzielt werden.Schlussfolgerung: MR-gestützte LITT ist eine sichere Methode bei der Behandlung von Lebertumoren. Wegen ihres minimal-invasiven Charakters ist die Komplikationsrate niedrig.     

Ultrasound-Navigated Interstitial Nd:YAG LaserCoagulation of Congenital Vascular Disorders

The treatment of voluminous hemangiomas or vascular malformations, particularly of the infiltrative type, is difficult and requires a combination of methods such as surgical excision, embolisation, laser therapy, sclerotherapy and magnesium spiking. The goal of this study was to investigate the efficacy of ultrasound-navigated interstitial Nd:YAG (Neodymium:Yttrium-Aluminium-Garnet) laser coagulation of hemangiomas and vascular malformations.Ultrasound-navigated interstitial Nd:YAG laser coagulation was performed on 21 patients with cavernous hemangiomas or vascular malformations. 12 patients had vascular malformations primarily of the venous kind, whereas arteriovenous components were predominant in 5 patients. In 4 children, an extensive hemangioma was the indication for interstitial laser therapy. Laser energy with a power of 7–10 W was applied via puncture canula through a 600 μm glass fiber and with support of ultrasound guided to the vessel wall. Immediately after laser application the blood flow was controlled with color-coded duplexsonography.Three months after lasertreatment, a volume reduction between 60% and 80% in hemangiomas (n = 4), between 20% and 70% in venous malformations (n = 12) and 0% to 70% in arteriovenous malformations (n = 5) was achieved. With exception of necrosis in one patient which healed spontaneously, no further complications occurred.Ultrasound-navigated interstitial Neodym-YAG-laser coagulation is an effective and minimally invasive method for treating voluminous hemangiomas and vascular malformations and is an alternative or complimentary to other therapies.     

支撑喉镜下低温等离子射频消融术与二氧化碳激光治疗声带白斑的疗效比较

目的比较低温等离子射频消融术与二氧化碳CO_2激光治疗声带白斑的临床疗效。方法回顾性分析分别采用等离子射频消融术(14例)、CO_2激光(15例)治疗的29例声带白斑患者的临床资料,比较两种方法术后疼痛程度、术后创面愈合情况和首次手术局部复发控制率等。结果两组术中术后疼痛差异无统计学意义;等离子组术后1个月黏膜恢复情况好于CO_2激光组;等离子组14例患者,5例复发,复发率35.71%;CO_2激光组15例患者,1例复发,复发率6.67%。结论激光与等离子射频消融术均为治疗声带白斑的微创的手术方式,CO_2激光组复发率低于等离子射频消融组     

Radiofrequency ablation of hepatocellular carcinoma in patients with and without cirrhosis

Introduction

Hepatocellular carcinoma (HCC) is a leading cause of death in patients with cirrhosis. Around 12% of all cases are associated with chronic liver disease without cirrhosis. The aim of our study was to compare primary tumor ablation rates, local tumor progression, safety, and long-term outcomes of radiofrequency ablation for single (less than 3.5 cm in diameter) or multiple HCC nodules (up to three nodules, each less than 3 cm) in both types of patients.

Methods

We treated 200 consecutive HCC patients recruited from a local sonographic screening program: 175 with cirrhosis and 25 with non-cirrhotic chronic liver disease.

Results

Complete ablation was achieved in 150 of the 175 patients (85.7%) (174 of the 206 nodules treated, 84.4%) in the cirrhotic group and in 24 of the 25 patients (96%) (27 of the 29 nodules treated; 93%) in the non-cirrhotic group. The two groups were not significantly different in terms of local tumor progression rates 1, 3, and 5 years after treatment (11%, 23%, and 24% among cirrhotics vs. 4%, 14%, and 14% among non-cirrhotic patients). Multifocal disease was more frequent among the cirrhotics. One-, three- and five-year survival rates were also similar in the cirrhotic (93%, 77%, and 61%) and non-cirrhotic groups (92%, 72%, and 64%). There were no treatment-related deaths. Severe complications occurred only in the cirrhotic group (2.2%).

Conclusions

Radiofrequency ablation is safe and effective treatment for HCC in patients with or without cirrhosis. The latter group has a significantly lower rate of multifocal disease.     

Hepatocellular carcinoma recurrence after percutaneous ablation therapy: helical CT patterns

Background: To categorize the helical computed tomographic (CT) intrahepatic recurrence patterns of hepatocellular carcinoma (HCC) after treatment with percutaneous ablation procedures. Methods: Double-phase helical CT studies of 67 patients with HCC recurrence were reviewed. The study population had undergone percutaneous ablation therapy procedures (multisession or single-session ethanol injection therapy, radiofrequency thermal ablation therapy, and interstitial laser photocoagulation therapy) for 120 HCC nodules. Results: Four patterns were defined. (A) Enhancing tissue within the edge of the ablated nodule on arterial phase images (ingrowth): this pattern was seen in five treated lesions (4.2% of all treated nodules) in five patients (7.5% of all patients with recurrence) 3–7 months after treatment (mean = 4 months). (B) Enhancing tissue around the treated nodule but continuously to its border on arterial-phase images (outgrowth): this pattern was found in 12 (10%) treated lesions in 12 patients (18%) 3–6 months after ablation (mean = 4 months). (C) Enhancing tissue within the same segment of the treated nodule on arterial phase images (spread): this pattern was detected in 10 (8%) treated lesions in 10 patients (15%) 3–6 months after treatment (mean = 5 months). (D) Enhancing tissue within different segments from the treated nodule on arterial phase images (progression): this pattern was identified in 34 patients (51%) with 53 (44%) treated tumors 5–22 months after ablation (mean = 8 months). A mixed pattern was found in six subjects (9%) with seven (6%) treated nodules. Among the 61 patients with a nonmixed pattern, there were 85 treated nodules with persistent necrosis, 17 treated nodules with local recurrence (pattern A or B), and 107 new nodules due to nonlocal recurrence (pattern C or D). Portal phase enhanced images and especially unenhanced images showed a lower detection rate and a lower lesion-to-liver conspicuity score (for all patterns but mainly for pattern C). Conclusion: Four patterns of recurrence after percutaneous ablation procedures can be categorized on double-phase helical CT and are best depicted on arterial phase images. Knowledge of these patterns is relevant for early detection and may be helpful in understanding the recurrence mechanism. Received: 25 September 2000/Accepted: 15 November 2000     

Laparoscopic liver packing to protect surrounding organs during thermal ablation

Abstract

Purpose: To evaluate the feasibility of liver packing for the prevention of injury to adjacent organs during thermal ablation of liver tumors. Material and methods: Between January 2005 and March 2010, 47 (52 sessions) patients with non-resectable liver tumors were treated and their tumors (55 primary carcinomas and 65 metastases, 1–12) were isolated from adjacent organs by laparoscopic liver mobilization and packing. Stereotactic radiofrequency ablation (SRFA) comprised body fixation, contrast-enhanced CT, 3-D planning, navigation, needle placement, control CT of needle positions (with image fusion), thermal ablation and control CT (with image fusion). Liver packing was removed laparoscopically thereafter. Complications, primary success and local recurrence rates were analyzed. Results: A total of 120 liver lesions with a median size of 2.4 cm (range 1–15 cm) were treated. Laparoscopic packing could be performed in all patients. The primary success rate of ablation was 91.6% (110/120) and the local recurrence rate was 4.5% (5/110). There was one perioperative death (1.9%). All remaining complications could be managed by radiological interventions. Despite broad surface contact thermal injury of surrounding organs could be prevented in all patients. Conclusion: Liver packing presents a viable and safe option for RFA of tumors with broad surface contact to surrounding organs with excellent local tumor control.     

Ablation of large HCCs using a new saline-enhanced expandable radiofrequency device

PurposeEvaluation of a new device designed to achieve large volumes of necrosis in hepatocellular carcinoma (HCC) nodules by application of radiofrequency ablation (RFA).Materials and Methods29 consecutive patients with 31 HCC nodules ≥3 cm in diameter (range 3–7.5 cm; mean diameter 5.5 cm) underwent ultrasound (US) guided percutaneous RFA using an expandable electrode with 7 active arrays and saline injection designed to create tissue ablation in areas of up to 7 cm (Starburst XLi-enhanced RFA device). Treatment was performed in general anesthesia (6 patients) or deep sedation (23 patients). Treatment efficacy was assessed by three-phase contrast-enhanced computed tomography (CT) and bimonthly US follow-up.ResultsOne to three electrode insertions (mean number 1.6) were performed in each patient. CT showed complete necrosis in 23/31 HCC nodules (74%) in 22 patients. Follow-up of these 22 patients ranged from 2 to 15 months (mean time 8.3 months). In 6/22 patients (28%) intrahepatic recurrence occurred within 5–10 months (mean time 8.3 months). Major complications were post-ablation syndrome in 7/29 (24%), peritoneal effusion in 4/29 (14%), pleural effusion in 2/29 (7%) and transient obstructive jaundice in 1/29 (3.4%) patients. One patient died 6 months after treatment because of tumor progression.ConclusionsIn the treatment of large HCC nodules, Starburst XLi-enhanced is an effective and safe device.     

Interstitial Laser Therapy of Congenital VascularMalformations with MRI Guidance

Introduction:Extratruncular, infiltrating congenital vascular malformations (CVM) are found in all organ systems. Large substance defects and diffuse blood loss may occur during surgical removal. Thus, conservative and interventional procedures are also applied, one of them being interstitial laser therapy (ILT).Patients and methods:Forty children with deep CVM underwent interstitial laser therapy with open MRI. The laser light guide was introduced into the malformation with a titan puncture needle and the tissue was thermically damaged by adequate selection of the physical parameters of the Nd:YAG 1064-nm laser. Beside the high soft-tissue contrast, MRI has the advantage of thermosensibility. For online thermomonitoring, we used 3 time-optimized MR sequences with a maximal velocity of 1 image in 3 seconds.Results: Positioning of the puncture needle was excellent in all applications and thermomonitoring was successful in 89%. A reduction of the tumor volume was observed in 36 patients at the 6-week follow-up. The volume of the malformations was reduced to 76%, on the average. Clinical improvement was seen in 78% of the cases. One fifth of the children are presently without symptoms. Thermic skin damage in 2 cases and intracorporal bare fiber tip loss in 1 case was found to be a complication.Discussion:Process control is decisive for successful interstitial laser therapy. Beside the high soft tissue contrast, MRI is characterized by a thermosensibility which does not allow invasive registration of temperature changes provoced by ILT inside the body.Summary: The introduction of open MR systems has enabled access to patients and interactive management directly in the magnetic field. MR-controlled interstitial laser therapy has to be included in the differential treatment of complicated congenital vascular malformations.     

Interstitial Laser Treatment of Venous Malformations

Objective: Venous malformations are aside from hemangiomas the most common vascular lesions observed in the pediatric age group. While interstitial Nd:YAG laser treatment was first used to treat hemangiomas in infancy, the mechanism of this treatment also can be used for venous malformations to reduce bulk and hypervascularisation, and improve contour and function.Study design: We reviewed our experience with the use of interstitial Nd:YAG laser therapy in treating complicated venous or mixed malformations. The lesions reported were particular troublesome because of significant cosmetic disfigurement, maceration or ulceration, bleeding, coagulopathy, painful swelling, and of potential functional impairment. During a 15-year period, 176 patients with predominantly venous malformations were treated by interstitial Nd:YAG laser treatment, and 157 of the 176 patients were treated additionally by transcutaneous Nd:YAG laser treatment with local ice cube cooling to protect the overlying skin. By using interstitial laser treatment, the laser beam was transmitted using a 0.6 mm bare fiber that was placed through an 16G abbocath into the lesion to be treated. The laser energy ranged from 5 W to 8 W in continuous mode. Color-coded duplex sonography was used for monitoring the procedure. Treatments were done under general anesthesia.Results:Overall, excellent results were achieved in 43% of patients and good results occured in 52%. In 5% treatment was deemed to have failed. Complications included paresthesia, dysesthesia, mild trismus, and local motoric plegia. All complications were transient and disappeared completely. Overall, satisfaction was high because of clear reduction of complaints, and all but 1 patient would have laser treatment again.Conclusions: On the base of our results we conclude that interstitial Nd:YAG laser treatment may successfully prevent enlargement and promote improvement with flattening of the lesion, less swelling, and improvement in the vascular red or bluish hue with minimal adverse effects.     

晚期胰体癌HIFU消融效果与CT靶皮距的相关性

目的探讨晚期胰体癌HIFU消融效果与CT靶皮距的相关性。方法将HIFU消融体积比>30%定为A组,即存在与HIFU相关的消融;≤30%定为B组,即不明确存在与HIFU相关的消融。根据上述分组,对20例晚期胰体癌肿物消融效果与CT靶皮距的相关性进行分析。结果 A组与B组之间CT靶皮距差异有统计学意义(P<0.05),且CT靶皮距每增加1cm,消融效果降低0.31倍;ROC曲线显示,当CT靶皮距为7.15cm时,其预测消融效果的敏感度为80.00%,特异度为70.00%,曲线下面积为0.81(P=0.02)。结合临床,将7cm作为CT靶皮距的分界值,预测消融效果的敏感度和特异度分别为77.80%和72.70%,OR值为9.33。结论晚期胰体癌HIFU消融效果与CT靶皮距呈负相关;CT靶皮距等于7cm可作为胰体癌HIFU治疗的适应证选择界值。     

MR imaging of intrahepatic cholangiocarcinoma

Background: The purpose of this study was to determine the magnetic resonance (MR) features of intrahepatic cholangiocarcinoma. Methods: MR imaging studies of seven cases of pathologically proven intrahepatic cholangiocarcinoma were retrospectively reviewed. Results: On MR images the tumors presented as a single mass (N = 5) or multiple nodules (N = 2), as welldelineated (N = 5) or ill-defined (N = 2), and as non-encapsulated (N = 7). Mean tumor diameter ranged from 6–14 cm (mean, 10 cm). On T1-weighted (TR/TE = 400–600/10–17 msec) images, the tumors were hypointense compared to the liver. The five tumors studied with dynamic MR imaging showed progressive centripetal filling-in after intravenous administration of a gadolinium chelate. On T2-weighted (TR/TE = 2000–2500/80–100 msec) images, all tumors were hyperintense compared to the liver; five were markedly hyperintense and two moderately hyperintense. Vascular encasement, bile duct dilatation within the tumor, and central scar were depicted on MR images in four, three, and two tumors respectively. Conclusion: The typical MR appearance of intrahepatic cholangiocarcinoma is a large well-delineated nonencapsulated tumor associated with intrahepatic venous encasement.     

The current role of minimally invasive therapies in the management of liver tumors

This is a review of minimally invasive therapy options for liver tumors, such as highly focused ultrasound, microwave ablation, and irreversible electroporation, as well as new aspects of radiofrequency ablation. Radiofrequency ablation is recommended for patients with early-stage HCC with up to 3 lesions with a tumor diameter within 3 cm and for patients with non-resectable liver metastasis. Indications and contraindications to treatment are designated, and different modalities for image-based therapy guidance are compared. Options for therapy monitoring and controlling are reviewed, namely intraprocedural tools, imaging and functional parameters and their evolution during therapy. Prevention and control of local recurrences is discussed. We also present a short review of current clinical results in treating liver metastasis and primary liver tumors.     

Contrast-enhanced ultrasound in planning thermal ablation of liver metastases: Should the hypervascular halo be included in the ablation volume?

Introduction

Liver metastases often exhibit a hypervascular halo during the arterial phase of contrast-enhanced ultrasonography (CEUS). This finding has no correlates on baseline gray-scale imaging, and it has never been characterized. The aim of this study was to identify the features of this halo and determine whether it should be included in the ablation volume during thermal ablation procedures.

Materials and methods

We prospectively enrolled 25 patients referred to our department for thermal ablation of liver metastases. Before treatment all patients underwent CEUS, and the maximum diameter of the metastatic lesion was measured before administration of the ultrasound contrast agent and during the arterial and portal venous phases of the contrast contrast-enhanced study. Maximum diameters in the different vascular phases were compared with the Turkey–Kramer test. Two biopsies were obtained from each lesion with a 21-gauge needle: 1) one from the center of the metastasis to confirm the diagnosis and 2) one from the hypervascular peripheral halo identified in the arterial phase at CEUS.

Results

The mean (±standard deviation) maximum lesion diameter was 2.67 ± 1.2 cm before contrast agent injection, 3.50 ± 1.4 cm during the arterial phase, and 2.71 ± 1.2 cm during the venous phase. The difference between maximum diameters measured before contrast enhancement and in the arterial phase was highly significant (mean: 0.84 ± 0.45 cm, p < 0.0001). Histological examination of halo specimens revealed inflammatory infiltrates with no evidence of tumor infiltration in 24/25 (96%) cases and normal hepatic parenchymal tissue in the 25th specimen.

Discussion

The hypervascular halo surrounding liver metastases during the arterial phase of CEUS represents a chronic inflammatory infiltrate, not tumor infiltration. However, since chronic inflammation appears to promote neovascularization and the production of tumoral growth factors, it seems wise to include the hypervascular halo in the intended-to-treat volume when planning the ablation procedure.