Conductance-Matrix Symmetries of a Three-Terminal Hybrid Device.

We present conductance-matrix measurements of a three-terminal superconductor-semiconductor hybrid device consisting of two normal leads and one superconducting lead. Using a symmetry decomposition of the conductance, we find that antisymmetric components of pairs of local and nonlocal conductances qualitatively match at energies below the superconducting gap, and we compare this finding with symmetry relations based on a noninteracting scattering matrix approach. Further, the local charge character of Andreev bound states is extracted from the symmetry-decomposed conductance data and is found to be similar at both ends of the device and tunable with gate voltage. Finally, we measure the conductance matrix as a function of magnetic field and identify correlated splittings in low-energy features, demonstrating how conductance-matrix measurements can complement traditional single-probe measurements in the search for Majorana zero modes.

Percutaneous Augmented Peripheral Osteoplasty in Long Bones of Oncologic Patients for Pain Reduction and Prevention of Impeding Pathologic Fracture: The Rebar Concept.

PURPOSE: To evaluate clinical efficacy/safety of augmented peripheral osteoplasty in oncologic patients with long-term follow-up. MATERIALS AND METHODS: Percutaneous augmented peripheral osteoplasty was performed in 12 patients suffering from symptomatic lesions of long bones. Under extensive local sterility measures, anesthesiology care, and fluoroscopic guidance, direct access to lesion was obtained and coaxially a metallic mesh consisting of 25-50 medical grade stainless steel micro-needles (22 G, 2-6 cm length) was inserted. PMMA for vertebroplasty was finally injected under fluoroscopic control. CT assessed implant position 24-h post-treatment. RESULTS: Clinical evaluation included immediate and delayed follow-up studies of patient's general condition, NVS pain score, and neurological status. Imaging assessed implant's long-term stability. Mean follow-up was 16.17 ± 10.93 months (range 2-36 months). Comparing patients' scores prior (8.33 ± 1.67 NVS units) and post (1.42 ± 1.62 NVS units) augmented peripheral osteoplasty, there was a mean decrease of 6.92 ± 1.51 NVS units. Overall mobility improved in 12/12 patients. No complication was observed. CONCLUSION: Percutaneous augmented peripheral osteoplasty (rebar concept) for symptomatic malignant lesions in long bones seems to be a possible new technique for bone stabilization. This combination seems to provide necessary stability against shearing forces applied in long bones during weight bearing.

Baastrup's disease (kissing spines syndrome): a pictorial review.

UNLABELLED: Excessive lordosis is a common finding and may produce mechanical pressure that causes repetitive strains of the interspinous ligament with subsequent degeneration and collapse. Baastrup's disease (kissing spine syndrome) is a term referring to close approximation of adjacent spinous processes due to degenerative changes of the spine. Baastrup's disease usually affects the lumbar spine, with L4-L5 being the most commonly affected level. There is higher occurrence at ages over 70 and no gender predilection. Symptoms include back pain with midline distribution that worsens during extension, is relieved during flexion and is exaggerated upon finger pressure at the level of interest. Diagnosis rests on clinical examination and imaging studies. The hallmark of imaging findings is the close approximation and contact of adjacent spinous processes, with all the subsequent findings including oedema, cystic lesions, sclerosis, flattening and enlargement of the articulating surfaces, bursitis and occasionally epidural cysts or midline epidural fibrotic masses. Proposed therapies include conservative treatment, percutaneous infiltrations or surgical therapies such as excision of the bursa or osteotomy. The purpose of this study is to illustrate the spectrum of imaging findings in Baastrup's disease and to emphasise upon including the syndrome in the list of potential causes of low-back pain. TEACHING POINTS: • Baastrup's disease refers to close approximation of adjacent spinous processes. • Diagnosis of Baastrup's disease is verified with clinical examination and imaging studies. • Contact of adjacent spinous processes results in oedema, sclerosis, flattening and enlargement. • Proposed therapies include conservative treatment, percutaneous infiltrations or surgical therapies.

In vivo characterisation of soft tissue tumours by 1.5-T proton MR spectroscopy.

OBJECTIVES: To determine whether proton magnetic resonance spectroscopy (1H-MRS) can help differentiate between benign and malignant soft tissue lesions, and to assess if there is a correlation between 1H-MRS data and the mitotic index. METHODS: MR measurements were performed in 43 patients with soft tissue tumours >15 mm in diameter. Six cases were excluded for technical failure. Examinations were performed at 1.5 T using a single-voxel point resolved spectroscopy sequence (PRESS) with TR/TE = 2000/150 ms. The volume of interest was positioned within the lesion avoiding inclusion of necrotic regions. In all patients, a histological diagnosis was obtained and the corresponding mitotic index was also computed. 1H-MRS results and histopathological findings were compared using the chi-squared test and correlation coefficient. RESULTS: Choline was detected in 18/19 patients with malignant tumours and in 3/18 patients with benign lesions. The three benign lesions included one desmoid tumour, one ossificans myositis and one eccrine spiradenoma. Choline was not detected in 15 patients with benign lesions or in one patient with dermatofibrosarcoma protuberans. Resulting 1H-MRS sensitivity and specificity were 95% and 83% respectively. CONCLUSIONS: Absence of choline peak is highly predictive of benign tumours suggesting that 1H-MRS can help to differentiate malignant from benign tumours. KEY POINTS: • 1H-MRS may allow differentiation between benign and malignant soft tissue lesions • Absence of choline peak is highly predictive of benign soft tissue lesions • Malignant tumours with a mitotic index >2/10 HPF had a positive choline peak • A choline peak may still be identified in some benign tumours.

Percutaneous ablative treatment of metastatic bone tumours: visual analogue scale scores in a short-term series.

INTRODUCTION: The aim of this study was to examine the role of palliative percutaneous secondary lesions bone treatment by comparing the visual analogue scale (VAS) scores of cryoablation plus vertebroplasty versus radiofrequency (RF) plus vertebroplasty so as to determine their feasibility, reliability and efficacy in a short-term series. METHODS: Combined RF thermal ablation plus osteoplasty or cryoablation plus osteoplasty was performed in osteolytic secondary bone localisations in 30 consecutive patients who were suffering from pain refractory to conservative therapies. We evaluated pain with the VAS during the preoperative period and at four hours, 24 hours, one week, one month, three months and six months post procedure. RESULTS: There were no statistically significant differences in the VAS score between patients treated with cryoablation plus osteoplasty and those treated with RF ablation plus osteoplasty at one week (p-value is 0.34), one month (p-value is 1), three months (p-value is 0.68) and six months (p-value is 0.65) post procedure. Patients treated with cryoablation plus vertebroplasty have less pain at four hours (p-value less than 0.001) and 24 hours (p-value less than 0.001) than patients treated with RF ablation plus vertebroplasty. CONCLUSION: Both RF ablation and cryoablation are optimal techniques in the treatment of painful bone metastatic cancer. Cryoablation achieves less treatment-related pain during the early period of follow-up and better volume control by real-time depiction of ablation margins.

Percutaneous vertebroplasty relieves pain in metastatic cervical fractures.

BACKGROUND: Percutaneous vertebroplasty is currently an alternative for treating vertebral fractures of the thoracic and lumbar spine, providing both pain control and vertebral stabilization. In the cervical spine, however, percutaneous vertebroplasty is technically challenging because of the complex anatomy of this region. QUESTIONS/PURPOSES: We evaluated the technical feasibility, complication rate, and ability of percutaneous vertebroplasty to provide pain relief in patients with painful metastatic cervical fractures. METHODS: We retrospectively reviewed 62 patients (24 men) who, between May 2005 and May 2009, underwent vertebroplasty to treat painful metastatic cervical fractures. Each patient was evaluated by a visual analog scale for pain, number of pain analgesics, and CT and MRI before, the day after, and at 3 months after the procedure. RESULTS: Two of the 62 patients had asymptomatic cement leakage in the soft tissues. We observed no delayed complications. Mean pretreatment and 24-hour posttreatment visual analog scale pain scores were 7.9±1.7 and 1.5±2, respectively. Immediately after surgery, the pain completely disappeared in 25 (40%) patients. Administration of analgesics was suspended in 34 (55%) patients whereas in 27 (39%) patients the median analgesics use decreased from two pills per day (range, 0-3) to 0 (range, 0-3). In two (3%) patients, analgesics administration was continued due to the persistence of pain. At 3 months, the patients reported a mean visual analog scale pain score of 1.7±2. CONCLUSIONS: Our data suggest, in selected patients, percutaneous vertebroplasty may be performed with a high technical success rate combined with a low complication rate, providing immediate pain relief lasting at least 3 months and a reduction in the use of analgesic drugs. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Percutaneous vertebroplasty or kyphoplasty.

Percutaneous vertebral augmentation techniques performed with vertebroplasty or kyphoplasty are safe and effective for the treatment of osteoporotic vertebral compression fractures, primary or secondary spine tumors, and selected traumatic fractures. This article compares the procedures and outlines their advantages and disadvantages. It concludes that vertebroplasty should be performed in most cases, but kyphoplasty is preferable in selected cases.

Diagnostic accuracy of portal-phase CT and MRI with mangafodipir trisodium in detecting liver metastases from colorectal carcinoma.

AIM: To compare the diagnostic accuracy of single section spiral computed tomography (CT) and magnetic resonance imaging (MRI) with tissue-specific contrast agent mangafodipir trisodium (MnDPDP) in the detection of colorectal liver metastases. MATERIAL AND METHODS: One hundred and twenty-five consecutive patients undergoing surgery for primary and/or metastatic disease were evaluated using CT (5 mm collimation and reconstruction interval, pitch 2), two-dimensional fast spoiled gradient echo (2D FSPGR) T1 and single shot fast-spin echo (SSFSE) T2 weighted breath-hold MRI sequences, performed before and after intravenous administration of MnDPDP. The reference standards were intraoperative ultrasound and histology. RESULTS: The per-patient accuracy of CT was 72.8 versus 78.4% for unenhanced MRI (p = 0.071) and 82.4% for MnDPDP-enhanced MRI (p = 0.005). MnDPDP-enhanced MRI appeared to be more accurate than unenhanced MRI but this was not significant (p = 0.059). The sensitivity of CT was 48.4% versus 58.1% for unenhanced MRI (p = 0.083) and 66.1% for MnDPDP-enhanced MRI (p = 0.004). The difference in specificity between procedures was not significant. The per-lesion sensitivity was 71.7, 74.9 and 82.7% for CT, unenhanced MRI, and MnDPDP-enhanced MRI, respectively; the positive predictive value of the procedures was respectively 84.0, 96.0 and 95.8%. MnDPDP-enhanced MRI provided a high level diagnostic confidence in 92.5% of the cases versus 82.5% for both unenhanced MRI and CT. The kappa value for inter-observer variability was >0.75 for all procedures. CONCLUSIONS: The diagnostic accuracy and sensitivity of MnDPDP-enhanced MRI is significantly higher than single section spiral CT in the detection of colorectal cancer liver metastases; no significant difference in diagnostic accuracy was observed between unenhanced MRI and MnDPDP-enhanced MRI.

Percutaneous implantation of a catheter with subcutaneous reservoir for intraarterial regional chemotherapy: technique and preliminary results.

PURPOSE: We present the technique and the preliminary results of percutaneous implantation of intraarterial catheters connected to a subcutaneous infusion reservoir for prolonged regional chemotherapy of hepatic and extrahepatic tumors. METHODS: Two hundred patients with primary or secondary hepatic neoplasms, pelvic, pancreatic, renal, lingual, and breast cancer underwent the procedure. The access was the left axillary artery (188 patients) and the femoral artery (12 patients). The catheter tip was placed in the hepatic (170 patients), hypogastric (18), splenic (4), internal thoracic (2), gastroduodenal (3), renal (2) or the external carotid artery (1). The catheter was connected to a subcutaneous reservoir and filled with heparin; chemotherapeutic infusion was subsequently started. RESULTS: One hundred percent immediate technical success was obtained. Forty-three of 200 (21.5%) patients had a complication: 29 patients had a catheter dislodgment, nine had arterial thrombosis, three had a pseudoaneurysm of the left axillary artery and two had a port pocket hematoma. Most complications (37/43, 86%) were treated percutaneously without interruption of chemotherapy. In only six cases (3% of the total population) was chemotherapy discontinued due to the complication itself. The mean duration of catheter patency was 7.2 months. CONCLUSION: Percutaneous placement of an intraarterial catheter is feasible and causes less discomfort to the patient than the surgical approach. The technique has an acceptable complication rate (21.5%), similar to that for surgical implantation (17.8%), with the advantage that in most cases the complications can be resolved percutaneously. This technique represents an alternative to surgical implantation in the treatment of liver metastases from colorectal cancer and opens new therapeutic possibilities for the local prolonged treatment of other kinds of tumor, though its clinical efficacy must be assessed in selected trials.

Percutaneous treatment with amphotericin B of mycotic lung lesions from invasive aspergillosis: results in 10 immunocompromised patients.

The aim of this study was to evaluate the efficacy of percutaneous treatment of pulmonary lesions from invasive aspergillosis in immunocompromised patients. From 1992 to 1998, ten patients (seven men and three women; mean age 56 years) affected by hematological neoplasms (8 acute myeloid leukemias, 2 non-Hodgkin's lymphomas) and post-chemotherapy prolonged neutropenia developed pulmonary lesions from invasive aspergillosis. A total of 13 lesions (diameter 2-7 cm, median 5 cm) were treated percutaneously due to insufficiency of the high-dose i.v. therapy; under CT guidance, a median of 10 cm3 per session of a 1 mg/cm3 diluted solution of amphotericin B was injected through a fine needle (21-22 G); 45 sessions overall were performed (one to five per lesion, median four), according to the volume of the nodules, tolerance, and complications. The results were retrospectively evaluated either radiologically or clinically. Complications were cough, mild hemoptysis, and small pneumothorax and/or pleural effusion. No major complications occurred. One month after the beginning of treatment, 8 lesions completely resolved, 4 greatly improved, and 1 was not significantly reduced. In all ten patients symptoms improved (eight of ten could restart chemotherapy as scheduled). After antiblastic retreatment, 1 patient had mycotic recurrence. In our experience transthoracic topical treatment with amphotericin B of single or few lung lesions from invasive aspergillosis was effective, affording a rapid improvement of the lesions and symptoms, and allowing continuation of chemotherapy as scheduled, thereby reducing the risk of recurrences.

[Computerized tomography with lipiodol in hepatocarcinoma. Assessment of its diagnostic accuracy with anatomo-pathological control]. / Tomografia Computerizzata con Lipiodol nell'epatocarcinoma. Valutazione dell'accuratezza diagnostica mediante controllo anatomo-patologico.

PURPOSE: To assess the diagnostic accuracy and predictive value of Lipiodol CT for hepatocellular carcinoma (HCC) before liver transplantation (OLT). MATERIAL AND METHODS: Seventy-eight cirrhotic patients awaiting OLT underwent Lipiodol CT to demonstrate the presence and extent of possible HCC. Radiologically, focal uptake areas with dense, homogeneous or "mosaic" iodized oil uptake were considered to be neoplastic nodules. All patients underwent OLT within 4 months of Lipiodol CT. Pathologic examination of the explanted livers was performed using the standard technique and, if necessary, with additional slices. Pathologic findings were compared with radiologic results to calculate the diagnostic accuracy and predictive value of Lipiodol CT in relation to both patients and lesions. RESULTS: Lipiodol CT depicted 61 focal areas of iodized oil uptake in 48 patients; pathologic examinations detected 57 HCC lesions in 42 patients (diameter .8 cm, mean 2.2 cm); agreement with radiologic diagnosis was found in 35 patients only. Patient by patient, Lipiodol CT had 83.3% sensitivity, 63.8% specificity, 74.3% diagnostic accuracy, 72.9% positive predictive value (PPV), and 76.6% negative predictive value. Lesion by lesion, Lipiodol CT showed overall sensitivity and PPV of 75.4-70.5%, 74-69.8% for "small" HCCs (diameter < or = 3 cm), and 72.9-71.1% for nodules < or = 2 cm in size. Eighteen uptake areas in 13 patients were diagnosed as HCC by Lipiodol CT but the finding was not confirmed at histology: 4 were hemangiomas and 14 corresponded to cirrhotic tissue without neoplastic foci. CONCLUSIONS: Our study, as the few others comparing radiologic results and pathologic findings of whole explanted liver, demonstrates that Lipiodol CT has relatively low diagnostic accuracy; particularly, specificity and PPV were limited by possible false positives, with HCC overstaging and mistakes in the indications/contraindications for OLT.

[The 3rd national workshop on defecography: the functional radiology of (neo) rectal ampullae (ileal reservoir, colo-anal anastomosis, continent perineal colostomy)]. / III workshop nazionale sulla defecografia: la fisioradiologia delle (neo)ampolle rettali (reservoir ileale, colo-ano-anastomosi, colostomia perineale continente).

A survey was made in 13 Italian centers with a questionnaire concerning the (a) indications, (b) postoperative complications, (c) functional results and (d) diagnostic imaging modalities related to the making of an ileal or colonic (neo) rectum. Ulcerative colitis (100%), familial polyposis (61.5%) and Crohn's disease (15.3%) were the most common indications for an ileal pouch; rectal cancer (7.96%), chronic inflammatory diseases (15.3%), diverticulosis, rectal prolapse, redundant colon and imperforate anus (7.6% each) were the most common indications for a colonic pouch. Postoperative complications included pelvic abscess (14%), sinus tract/dehiscence (10%) and bowel obstruction (9%). When compared with the S and W variants, the J-shaped ileoanal pouch proved superior because urgency and fecal retention rates were lower (18.4% vs. 44.4% and 23% vs. 28.6%, p < 0.01 and p < 0.05, respectively), despite slightly more frequent staining episodes (15.8% vs. 11.1%; p < 0.05). As for colonic ampullae, fecal retention and provoked evacuation were more frequent in the J pouch and after gracileplasty; urgency and incontinence in the straight colo-anal anastomosis (33.3% vs. 22.2% and 41.6% vs. 33.3%, respectively). The functional outcome was assessed by anal endosonography (available in 4/13 centers), defecography and anorectal manometry. Abnormal findings included: (a) reduced capacity, barium leakage, anal gaping, sphincter damage (urgency and incontinence); (b) barium retention, pouch dilatation, split evacuation, knobs and strictures (fecal retention).

Complicated jejunal diverticulosis: report of a case.

The authors report a case of complicated multiple jejunal diverticulosis and review the data from the literature on this pathology. A 74-year-old man was admitted to our unit presenting with symptoms of intestinal obstruction. He had previously experienced three episodes of the same symptomatology with melena. Endoscopy excluded gastroduodenal or colonic bleeding; an X-ray of the small bowel detected multiple large jejunal diverticula. The patient underwent surgery: a jejunal resection was performed just below the Treitz angle extending about 60-70 cm. The postoperative course was uneventful and the patient was discharged on the 8th postoperative day. At present, the patient is doing well and has not since demonstrated any symptoms of either intestinal obstruction or melena.

Giant sigmoid diverticulum.

The case of a giant diverticulum of the sigmoid colon in a 74 year-old woman is reported. The diverticulum had perforated into the urinary bladder and required a 3-phase operation with resection of the sigmoid colon and urinary bladder. Giant diverticulum is considered a rare complication of diverticulosis. Generally, it is a pseudo-diverticulum that grows due to a valve mechanism working in the neck of the diverticulum. The differential diagnosis lies mainly between intestinal duplication and pneumatosis cystoides. Surgical therapy yields favorable results.

[Percutaneous transjugular intrahepatic portosystemic shunt (TIPS). The preliminary experience and proposal of a new method]. / Derivazione portosistemica intraepatica per via percutanea trans-giugulare (TIPS). Esperienza preliminare e proposta di una nuova metodica.

A new interventional procedure employing metallic stents has been recently suggested to perform percutaneous portosystemic shunts in the treatment of variceal bleeding in portal hypertension; the technique is called TIPSS (transjugular intrahepatic portosystemic stent shunt). This percutaneous treatment presents several advantages over surgery: the shunt diameter can be calibrated according to the degree of portal hypertension; moreover, TIPSS can be performed in patients waiting for liver transplantation because it does not alter the vascular anatomy of liver. The original technique employed transhepatic portography. In this paper the authors report on their personal experience and present their series of 4 patients with portal hypertension and variceal bleeding, in whom TIPSS was performed utilizing noninvasive US guidance. Variceal bleeding was successfully treated in all patients and variceal distension was also obtained.

[The transcatheter recanalization of occluded portosystemic shunts]. / Ricanalizzazione attraverso catetere degli shunt portosistemici occlusi.

UNLABELLED: The authors present their personal experience in percutaneous treatment of portosystemic shunt occlusion and stenosis by percutaneous transluminal angioplasty (PTA) and fibrinolytic local infusion. Twelve patients with portosystemic shunt stenosis or occlusion were percutaneously treated. In 8 patients only PTA was performed, 4 were treated with local fibrinolytic infusion, in 3 of the latter cases this treatment was followed by PTA. In all 12 patients recanalization was successful and non complications arose. Six patients died in the following 15 months, none due to rebleeding. In 5 of these patients the shunt was patent at post-mortem examination. In the 6 patients still alive in the follow-up period (2 to 25 months, mean 14.5 months) the shunt was patent in 4 and occluded in 2. IN CONCLUSION: percutaneous treatment with PTA or fibrinolytic local infusion is preferable in non-functioning portosystemic shunt; further surgery is always extremely risky in such patients.

[Quantitative computerized tomography in the study of osteoporosis. Our experience]. / La tomografia computerizzata quantitativa nello studio dell'osteoporosi. Nostra esperienza.

In the diagnosis of osteoporosis there are, today, several techniques for investigating bone mineral density. In this work the authors evaluate the sensitivity of Computed Tomography in the diagnosis of this metabolic disease, because of the built-in competence of this method in determining the density of the anatomical tissues. In a randomised study the Authors performed Single Energy Quantitative Computed Tomography (SEQCT) in estimating the bone mineral density of lumbar vertebrae in 44 female patients. The data obtained were correlated, using the Student "t" test, to the measurements acquired, in the same group of patients, employing Dual Energy X-ray Absorptiometry (DEXA), 27 patients, and Total Body DEXA, 17 patients. Results revealed a good correlation between SEQCT and DEXA (R = 0.89) and statistical significance (p < 0.001). On the contrary there is not a good correlation (R = 0.58) if SEQCT is compared to Total Body DEXA. According to our experience Quantitative Computed Tomography is useful in diagnosis osteoporosis and it should be performed in all post-menopausal patients. This method, which has a high level of precision, is cheap and easily adaptable to every Computed Tomography. Because of the high X-ray dose rate, only DEXA should be performed in monitoring patients undergoing therapy.

[Percutaneous transcatheter embolization of deep visceral pseudoaneurysms]. / Embolizzazione transcatetere percutanea degli pseudoaneurismi viscerali profondi.

The authors present their experience with the percutaneous embolization of 13 splanchnic aneurysms and pseudoaneurysms (2 pseudoaneurysms of gastroduodenal artery, 3 of the hepatic artery, 7 renal pseudoaneurysms, 1 aneurysm of the splenic artery). In 9 of 13 cases the lesions were iatrogenic. Embolizing devices and techniques are described. Percutaneous embolization was successful in 12 of 13 cases, and useless in 1 case of renal pseudoaneurysm. In the 12 successfully treated cases the lesions were still occluded in the follow-up period. Transcatheter percutaneous embolization is the elective treatment in splanchnic aneurysms and pseudoaneurysms; surgery must be performed only when embolization fails.