Preoperative magnetic resonance and intraoperative ultrasound fusion imaging for real-time neuronavigation in brain tumor surgery.

PURPOSE: Brain shift and tissue deformation during surgery for intracranial lesions are the main actual limitations of neuro-navigation (NN), which currently relies mainly on preoperative imaging. Ultrasound (US), being a real-time imaging modality, is becoming progressively more widespread during neurosurgical procedures, but most neurosurgeons, trained on axial computed tomography (CT) and magnetic resonance imaging (MRI) slices, lack specific US training and have difficulties recognizing anatomic structures with the same confidence as in preoperative imaging. Therefore real-time intraoperative fusion imaging (FI) between preoperative imaging and intraoperative ultrasound (ioUS) for virtual navigation (VN) is highly desirable. We describe our procedure for real-time navigation during surgery for different cerebral lesions. MATERIALS AND METHODS: We performed fusion imaging with virtual navigation for patients undergoing surgery for brain lesion removal using an ultrasound-based real-time neuro-navigation system that fuses intraoperative cerebral ultrasound with preoperative MRI and simultaneously displays an MRI slice coplanar to an ioUS image. RESULTS: 58 patients underwent surgery at our institution for intracranial lesion removal with image guidance using a US system equipped with fusion imaging for neuro-navigation. In all cases the initial (external) registration error obtained by the corresponding anatomical landmark procedure was below 2 mm and the craniotomy was correctly placed. The transdural window gave satisfactory US image quality and the lesion was always detectable and measurable on both axes. Brain shift/deformation correction has been successfully employed in 42 cases to restore the co-registration during surgery. The accuracy of ioUS/MRI fusion/overlapping was confirmed intraoperatively under direct visualization of anatomic landmarks and the error was < 3 mm in all cases (100 %). CONCLUSION: Neuro-navigation using intraoperative US integrated with preoperative MRI is reliable, accurate and user-friendly. Moreover, the adjustments are very helpful in correcting brain shift and tissue distortion. This integrated system allows true real-time feedback during surgery and is less expensive and time-consuming than other intraoperative imaging techniques, offering high precision and orientation.

Guidelines and good clinical practice recommendations for contrast enhanced ultrasound (CEUS) in the liver--update 2012: a WFUMB-EFSUMB initiative in cooperation with representatives of AFSUMB, AIUM, ASUM, FLAUS and ICUS.

Initially, a set of guidelines for the use of ultrasound contrast agents was published in 2004 dealing only with liver applications. A second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some non-liver applications. Time has moved on, and the need for international guidelines on the use of CEUS in the liver has become apparent. The present document describes the third iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS) using contrast specific imaging techniques. This joint WFUMB-EFSUMB initiative has implicated experts from major leading ultrasound societies worldwide. These liver CEUS guidelines are simultaneously published in the official journals of both organizing federations (i.e., Ultrasound in Medicine and Biology for WFUMB and Ultraschall in der Medizin/European Journal of Ultrasound for EFSUMB). These guidelines and recommendations provide general advice on the use of all currently clinically available ultrasound contrast agents (UCA). They are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis and improve the management of patients worldwide.

Ultrasonography of the neck.

The anatomic and pathologic involvement of the structures in the neck can be accurately studied with small parts ultrasonography. The thyroid and parathyroid glands and nodal chains are treated in this article; masses of the neck spaces are not considered because of their relative rarity.

Radiofrequency tissue ablation: increased lesion diameter with a perfusion electrode.

RATIONALE AND OBJECTIVES: We sought to induce large zones of coagulation necrosis using radiofrequency (RF) with perfusion electrodes and to define optimal parameters for this system. METHODS: We developed RF electrodes with internal cannulas to enable tip perfusion. Lesions were created with monopolar RF in ex vivo and in vivo liver and muscle tissue with and without perfusion of the electrode tip using 0 degree C saline. In separate experiments, wattage, current, procedure duration, tip exposure, and perfused tip temperatures were studied. RESULTS: In ex vivo liver tissue, a maximum lesion diameter of 3.1 cm without charring occurred with perfusion at 12 min and 50 W. In in vivo liver tissue with perfusion (tip temperature = 25-35 degrees C) and a 3-cm tip exposure, 80 W were deposited in muscle tissue and 65 W in liver tissue for 12 min without inducing charring. Lesion diameters were 4.5 cm and 2.4 cm, respectively. By comparison, without perfusion a maximum of 20 W could be deposited into either tissue type, resulting in 1.8-cm muscle lesions and 1.2-cm liver lesions. Tip temperatures between 45 degrees C and 55 degrees C resulted in charring. Smaller but predictable lesion diameters were created with a lower power, a shorter tip exposure, or both. Of all the parameters, diameter correlated best with the current applied. CONCLUSION: Perfusion of RF electrodes with chilled saline allows for increased power deposition without tissue charring, increasing the volume of coagulation necrosis created with a single electrode insertion. Perfusion electrodes therefore might decrease the number of probe insertions required for percutaneous tumor ablation therapy or allow for the treatment of larger lesions.

ULtrasonography in acute cholecystitis.

Forty cases of acute cholecystitis, surgically and pathologically confirmed, were investigated with ultrasound. Echographic diagnosis was possible in 34 patients (85%): special emphasis was laid on wall thickening (90% of cases, with a mean wall thickness of 8.08 mm), evidence of an echofree layer within the wall (67.5% of patients) and a lumen greater than 4 cm with thick walls. Associated cholelithiasis was demonstrated in 28 of these patients. In five more patients specific wall signs were absent and cholelithiasis was the only detectable sign of the disease. In only one patient was there no echographic sign of acute cholecystitis.

Intussusception of the bowel: a new sonographic pattern.

The ultrasonic findings in a case of small bowel intussusception in an adult patient are presented. The sonographic features vary with the scanning plane. Scans along the longitudinal axis of the involved segment show a diagnostic pattern, not previously described: three parallel stripes of low echogenicity delineating two reflective areas.

Fine-needle aspiration biopsy of liver focal lesions ultrasonically guided with a real-time probe. Report on 126 cases.

Ultrasonically guided fine-needle biopsy of focal liver lesions was performed in 126 patients to obtain a definitive diagnosis. Percutaneous target puncture and tissue aspiration were guided by a real-time linear-array probe with a central canal for needle insertion. The procedure is simple and rapidly performed; a correct cytological diagnosis was established in 94% of the punctured masses. No adverse reactions of clinical significance were observed. Fine-needle biopsy with ultrasound guidance by real-time scanning may be the procedure of choice to obtain a tissue diagnosis in patients with hepatic masses.

New applications of ultrasonography: interventional ultrasound.

Since 1975-80, worldwide but mostly in Europe and Japan, sonography has become the imaging technique of choice for guiding percutaneous interventional procedures for diagnostic or therapeutic purposes. In the last 10 years, the most important advances in interventional ultrasound have occurred in therapeutic applications, fostering and facilitating the development of the so-called minimally-invasive techniques. Among all these new applications for the treatment of fluid collections, inflammatory diseases, benign and malignant tumors, the most recent dramatic advances have occurred in primary and secondary liver malignancies, which will be the focus of this review. The rationale for the local treatment of primary and secondary liver cancers differs according to the success of conventional treatments (e.g. surgery and chemotherapy) and to the survival rates of such conditions, depending on clinical stage, patient age, associated diseases, and so on. Ultrasound-guided percutaneous therapies for liver cancer can be divided into: (1) direct intratumoral injection of chemical agents, such as ethanol, hot saline and acetic acid; and (2) thermally-mediated techniques, such as radiofrequency ablation, interstitial laser photocoagulation, microwave therapy or cryotherapy. Through different mechanisms of action, all these methods induce cell death by coagulative necrosis. The clinical efficacy of some of these techniques has been clearly established, like percutaneous ethanol injection in the treatment of hepatocellular carcinoma. In contrast, experience with the other techniques is much more preliminary, mostly due to the limited availability of sufficient clinical trials and to the fascinating speed of technological development. We review the state-of-the-art of the two most promising techniques, namely radiofrequency ablation and interstitial laser photocoagulation, and the present preliminary clinical data in the treatment of hepatocellular carcinomas and liver metastases. Radiofrequency energy is delivered to the tumors by means of electrode-needles (14-17 G) electrically insulated along all but the distal portion of the shaft and percutaneously introduced into the targets under ultrasound guidance. In the short history of this method, several technologies have been tested and used, but 'multiple-hook' and 'internal-cooling' electrodes are currently the leading choices, providing large necrosis volumes (up to 5 cm in diameter for a single 12-min application with an array of three internal-cooling electrodes) in short sessions, under local or general anesthesia. Radiofrequency ablation has proved its usefulness in the treatment of hepatocellular carcinomas, achieving complete necrosis in over 85-90% of cases in lesions smaller than 5 cm in diameter and in single sessions, with a low rate (< 10%) of local recurrences. In the treatment of liver metastases, whose very poor responsiveness to percutaneous ethanol injection and other 'chemical' therapies is extensively reported in the literature, radiofrequency ablation has 65-75% reported complete efficacy in the control of local tumor growth in lesions not exceeding 4 cm. Such great efficacy has been so far coupled with very low rates of major side-effects (< 2%), most of them requiring no surgical repair. Interstitial laser photocoagulation induces thermally-mediated coagulation through thin optic (Nd:YAG) fibers percutaneously inserted into the target under ultrasound guidance. Multiple fibers (beam splitters) are usually required to achieve a sufficiently wide necrosis volume. The reported success rate (complete necrosis and local control of tumor growth) ranges 45-75%) of the lesions, mostly liver metastates from colorectal carcinoma. An equally low rate of complications is reported for interstitial laser photocoagulation as for radiofrequency ablation, that is no more than 2-3% of cases. (ABSTRACT TRUNCATED)

Inclusion-cytology versus smear-cytology in fine needle abdominal biopsy.

1568 patients underwent percutaneous fine needle biopsy (22-23 g. Chiba). 761 of these had histologic type confirmation of malignant disease. Among the latter, 313 cases had adequate samples retrieved from the same lesion for smear cytology (SC) and inclusion cytology (IC), 400 for SC alone (378 performed before the use of IC) and 48 for IC alone. SC was stained by Papanicolaou and MGG, IC by haematoxylin-eosin technique. In SC + IC group typing accuracy was 0.64 for SC and 0.86 for IC, in SC group was 0.66, in IC group was 0.87. IC permitted an easier preparation and interpretation of special stains. In conclusion, IC routine is recommended. Some interesting observations were possible because material was collected from three hospitals.

Adjuvant therapy with essential fatty acids (EFAs) for primary liver tumors: some hypotheses.

Hepatocarcinoma is responsible for approximately 1 million deaths annually. It is usually discovered at an advanced stage and, if inoperable, has a poor prognosis. New therapies combining chemotherapy, hyperthermia, radiotherapy and immunomodulators have been recently attempted with various levels of success. Once the tumor is detected at an early stage, some possibilities of cure seem to emerge either by intratumoral percutaneous injection (PEI) of alcohol or by chemoembolization and interstitial hyperthermia. When the tumor volume is more than 5 cm, these therapies are less successful and radiotherapy can be used. All the techniques described have some limits; PEI, for instance, does not achieve a complete eradication of lesions > 3 cm and a non-homogenous alcohol distribution within the tumor leads to areas of necrosis. Radiotherapy, even if effective, is limited by dose-related radiation hepatitis. Another important limiting factor is the incomplete response to therapy and tumor recurrence. Essential fatty acids, especially gamma linolenic acid (GLA) and eicosapentaenoic acid (EPA) are discussed here for their ability to control primary tumor proliferation and increase response to chemotherapy, radiotherapy and hyperthermic treatment, thanks to their effects on cellular membranes (increased lipoperoxidation and modification of tumor stroma).

Percutaneous interstitial chemotherapy of a small hepatocellular carcinoma under ultrasound guidance.

A small (less than 3 cm) inoperable hepatocellular carcinoma was treated with percutaneous interstitial chemotherapy (PIC). 5-Fluorouracil was injected by a fine needle under ultrasound guidance. After 3 months a fine needle biopsy (FNB) yielded fibronecrotic material. After 18 months another FNB yielded steatosis and dysplastic cells and the lesion showed no increase in size. PIC could be an interesting alternative treatment for small tumors unresponsive to conventional therapies.

240 hepatocellular carcinomas: ultrasound features, tumor size, cytologic and histologic patterns, serum alpha-fetoprotein and HBs Ag.

Two hundred and forty cases of hepatocellular carcinomas (HCC), diagnosed by ultrasonography and fine needle biopsy, were studied. The following parameters were investigated: 1. echo features (240 cases) - hypoechoic, 54; hyperechoic, 56; complex, 112; isoechoic with halo, 18; 2. tumor size (240 cases) - single tumor under 4.5 cm, 30; single tumor over 4.5 cm, 74; multiple masses or diffuse, 136; 3. cytologic pattern (240 cases) - well and medium differentiated, 144; pleomorphic, 43; poorly differentiated, 28; unclassified, 25; 4. histologic pattern (157 cases) - trabecular, 74; solid, 42; acinar, 1; mixed, 2; unclassified, 38; 5. alpha-fetoprotein (AFP) level (185 cases) - under 20 ng/ml, 79; between 20 and 320 ng/ml, 40; over 320 ng/ml, 66; 6. HBs Ag (208 cases) - present in 56 cases; 7. cirrhosis (102 cases) - present in 79 cases. Some of the above parameters were correlated with one another. There was: 1. a highly significant frequency of the hypoechoic feature among small HCC; 2. a percentage of AFP-producing tumors increasing with tumor size; 3. no relationship between AFP production and cytologic or histologic pattern; 4. no relationship between tumor size and cytologic or histologic pattern. However, among the small HCC, all the 9 HCC with a diameter of less than 3 cm showed a trabecular pattern and well-differentiated cells. Cirrhosis was present in every patient with a small HCC. Since the discovery of a small HCC is an incidental ultrasonographic finding in the context of severe liver disease, ultrasonographic monitoring of cirrhotic patients is the best available strategy to screen for small HCC.

[Familial multiple bilateral carcinoma of the kidney: clinical strategy and surgical approach]. / Carcinoma renale bilaterale multiplo familiare: strategia clinica e tattica chirurgica.

A case of familiar bilateral multicentric RCC in a young woman is an ideal model to evaluate preoperative and intraoperative diagnostic and surgical tools in order to achieve two distinct goals: the oncologic radicalness and the renal function preserved. Radical bilateral nephrectomy, the renal hypothermia by perfusion of both kidneys, the bench high resolution sonography of parenchyma, the choose of one kidney suitable for conservative surgery, the resection of suspect lesions with intraoperative pathology, the reconstructive bench surgery, the autotransplantation, are the steps accurately performed with particular concern to eradication of all the tumoral lesions present in the kidneys. The results confirm that renal function has been preserved with this method. Radicalness should be appointed by a longlasting follow up. However, as it is discussed, conservative surgery, when accurately performed can give results not different from radical demolitive surgery. In this paper tools to improve diagnostic and therapeutic methods are described in order to increase the diagnostic accuracy and the therapeutic efficacy. The possibility that this multiple RCC can be a part of the abnormalities occurring in the Von Hippel-Lindau syndrome does not change the surgical approach, being the RCC the worst prognostic factor of the syndrome.

[Morphologic imaging of thyroid carcinoma]. / L'imaging morfologico del carcinoma tiroideo.

Ultrasonography (US) is the choice morphological imaging modality in the study of thyroid carcinomas. The present technological evolution (high frequency probes, development of Colour-Doppler) allows the detection of small non-palpable nodules, being able to define, in a high percentage of cases, features pointing to the malignant character of a thyroid mass, although the definite assessment of malignancy (invasion of adjacent structures, metastatic cervical nodes) is quite rare. From a diagnostic viewpoint US is required to identify nodules with suspect features, to be submitted to fine needle aspiration biopsy. Moreover, US plays a basic role in the staging--at the cervical level--of carcinomas as well as in the post-operative follow-up. The other imaging modalities (Computed Tomography, Magnetic Resonance Imaging) play a limited role in both staging and post-operative follow-up.

Percutaneous ethanol injection of autonomously functioning thyroid nodule.

Percutaneous ethanol injection (PEI) is proposed for treatment of autonomously functioning thyroid nodule, especially for small-mid-sized solitary nodules, for patients refusing the other methods or not proving responsive to radioiodine, or for patients with non toxic nodule. The injection is performed under color Doppler sonography guidance, evaluating the most vascularized areas of the tumor where to primarily inject ethanol solution with 21-22 gauge needles. Serum TSH, FT4, FT3 and TG levels are measured before each treatment session and 3,6,12,24 and 36 months after the end of therapy. Complete remission was achieved by different authors in 86% of cases and the efficacy of response was shown to be inversely proportional to the nodule volume. When TSH remains undetectable, a second cycle of PEI can be performed. If there is complete lack of blood flow signals on color or power Doppler with persisting thyroid hyperfunction, sonographic contrast media can be administered i.v. to assess residual areas of intranodal hypervascularity. In patients with unsuppressed TSH levels before treatment, hormonal changes cannot be used as marker response. Disappearance of nodular hypervascularity at color Doppler sonography and complete normalization of the scintigraphic pattern is usually observed in all cases. PEI is generally well tolerated; no recurrences of the disease and no cases of hypothyroidism have been reported.

Virtual navigator automatic registration technology in abdominal application.

Real-time Ultrasound (US) image fusion with a pre-acquired second imaging dataset - Computed Tomography (CT), Magnetic Resonance Imaging (MRI) and/or CT/PET - has become widely used in recent years for both diagnosis and image-guided interventional procedures. Liver and kidneys are the main focused anatomical districts, related to abdominal application. There are still nowadays some drawbacks, regarding the adoption of the fusion imaging technique in everyday practice especially regarding its ease of use and the time needed in order to obtain a precise real-time fusion between US and the second imaging modality. The present work is a preliminary study on the feasibility and practical use of an Automatic registration algorithm for CT-US real-time fusion imaging. Data obtained by tests performed on a Doppler phantom, for the assessment of the precision of the registration procedure and in-vivo Automatic registration tests, are presented.

Percutaneous laser ablation of metastatic lymph nodes in the neck from papillary thyroid carcinoma: preliminary results.

CONTEXT: Percutaneous laser ablation (PLA) may be useful in treating patients with metachronous metastatic lymph nodes in the neck. OBJECTIVE: Our objective was to assess PLA as a treatment of difficult-to-treat metachronous cervical lymph node metastases from papillary thyroid carcinoma. DESIGN AND SETTING: We conducted a retrospective analysis of prospectively collected data at a public hospital. PATIENTS: Fifteen patients with previous resection of papillary thyroid carcinoma with elevated serum levels of thyroglobulin (Tg) or anti-Tg antibodies (TgAbs) and 24 metachronous nodal metastases treated between September 2010 and April 2012 were followed with [¹8F]fluorodeoxyglucose (¹8FDG) positron emission tomography (PET)/computed tomography (CT) and contrast-enhanced ultrasound (CEUS). INTERVENTION: Intervention was PLA. OUTCOME MEASURES: Technique feasibility and technical success were evaluated. Tg/TgAb serum levels and ¹8FDG-PET/CT, and CEUS appearance were assessed at 6 and 12 months and compared with baseline. Complications were recorded. RESULTS: PLA was always feasible, and technical success was achieved in all patients. At 6 months, local control was achieved in 11 of 15 patients (73%), with 6 (40%) having serum Tg/TgAb normalized (P = .017 vs baseline). Whereas 20 of 24 (83%) nodes were negative at ¹8FDG-PET/CT and CEUS (P < .001 vs baseline), 4 were ¹8FDG-PET/CT-positive (3 also CEUS-positive). At the 12-month follow-up, local control was achieved in 10 of 14 patients (71.4%). Sixteen of 20 nodes (80%) were negative at ¹8FDG-PET/CT and CEUS (P < .001 vs baseline), 4 were ¹8FDG-PET/CT-positive (2 also CEUS-positive). Four of 10 (40%) patients had normalization of serum Tg/TgAb (P = .098 vs baseline). No major complications occurred. CONCLUSIONS: PLA is potentially feasible, safe, and effective for the treatment of metachronous cervical nodal metastases from papillary thyroid carcinoma. This procedure may reduce or delay a large number of highly invasive repeat neck dissections.