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Point-of-care ultrasound (POCUS) has become a topical subject and can be applied in a variety of ways with differing outcomes. The cost of all diagnostic procedures including obstetric ultrasound examinations is a major factor in the developing world and POCUS is only useful if it can be equated to good outcomes at a lower cost than a routine obstetric examination. The aim of this study was to assess a number of processes including accuracy of images and reports generated by midwives, performance of a tablet-sized ultrasound scanner, training of midwives to complete ultrasounds, teleradiology solution transmissions of images via internet, review of images by a radiologist, communication between midwife and radiologist, use of this technique to identify high-risk patients and improvement of the education and teleradiology model components. The midwives had no previous experience in ultrasound. They were stationed in rural locations where POCUS was available for the first time. After scanning the patients, an interim report was generated by the midwives and sent electronically together with all images to the main hospital for validation. Unique software was used to send lossless images by mobile phone using a modem. Transmission times were short and quality of images transmitted was excellent. All reports were validated by two experienced radiologists in our department and returned to the centers using the same transmission software. The transmission times, quality of scans, quality of reports and other parameters were recorded and monitored. Analysis showed excellent correlation between provisional and validated reports. Reporting accuracy of scans performed by the midwives was 99.63%. Overall flow turnaround time (from patient presentation to validated report) was initially 35 min but reduced to 25 min. The unique mobile phone transmission was faultless and there was no degradation of image quality. We found excellent correlation between final outcomes of the pregnancies and diagnoses on the basis of reports generated by the midwives. Only 1 discrepancy was found in the midwives' reports. Scan results versus actual outcomes revealed 2 discrepancies in the 20 patients identified as high risk. In conclusion, we found that it is valuable to train midwives in POCUS to use an ultrasound tablet device and transmit images and reports via the internet to radiologists for review of accuracy. This focus on the identification of high-risk patients can be valuable in a remote healthcare facility.

The use of CEUS has expanded the field of interventional ultrasound and established new possibilities in patient management and diagnostic capabilities. CEUS is a powerful diagnostic tool due to excellent time resolution and the possibility to keep a suspected lesion in the scanning plane throughout the entire contrast study. This feature frequently results in CT negative metastases being diagnosed with CEUS. CEUS increase procedure success in biopsy of conventional B-mode “invisible” lesions or large tumors with necrosis. CEUS performed before and immediately after ablation procedures greatly improve the success rate. CEUS can be of great value utilized intracavitary during abscess drainage or biliary and urological interventions. Fusion ultrasound is an image application, whereby US images are presented simultaneously with corresponding, previously acquired images obtained from other imaging modalities such as CT, PET or MRI. CEUS and fusion, and especially the combination of the two, has become decisive factors in liver imaging. These technologies increase detection sensitivity, enable immediate diagnosis of malignant versus benign lesion, plus facilitate differentiation between benign lesions such as hemangiomas, adenomas and FNH. The basic advantage of image fusion with ultrasound is the possibility to combine the dynamic features of ultrasound with the virtues of CT and MR imaging. In addition, fusion used in combination with CEUS has a great potential for increasing procedure technique during guiding of interventional procedures US-guided ablation of non-operable malignant liver lesions with RF or MW has become a well-established treatment that can be performed either percutaneously, laparoscopically, intraoperatively, during laparotomy or in combination with liver surgery. Ultrasound remains the most used guiding modality for these procedures for obvious reasons. Dedicated devices for US-guidance of these procedures are rapidly evolving and CEUS and fusion performed before and after the ablation procedure improves the treatment results. In case of non-operability, however, biopsy of lesions seen at CT, PET or MRI remains mandatory to confirm malignancy before chemotherapy or image-guided ablation with RF, MW, cryo or similar techniques. Use of CEUS and fusion may enable biopsy of otherwise ultrasound invisible lesions. Use of CEUS and fusion may change the classic indications for biopsies and reduce the number of diagnostic biopsies. US-guided biopsies, however, will still be required in case of equivocal findings and likely will continue to serve as Gold-Standard. In addition, CEUS may visualize bleeding related to interventional US thus reducing the risk of severe complication. Interventional US has countless applications and recent technological achievements described herein have provided new valuable elements to its use.

Transrectal ultrasound (TRUS), sometimes named endoanal ultrasound, is performed with dedicated endoprobes and in the hands of an experienced user, can represent an indispensable tool in evaluation of anal fistulae and abscesses in the perianal and – rectal region plus staging of anal and rectal cancer. The spatial resolution of TRUS is unsurpassed, however, MRI or CT should be used to provide a complementary overview of the entire region. The anal canal constitutes the distal approximately 4 cm of the bowel system and represents the transition between mucosal lining in the rectum and squamous cell lining of the skin. The ultrasound appearance is dominated by the change in anatomy of the muscular layers of the wall which in this small segment is made up solely of the circular, concentric muscles representing the internal and external anal sphincter. The anal canal is divided into 3 levels relating to the sphincter muscles. In rectum 5 distinctive layers corresponding to the underlying anatomy can be identified with TRUS and correlated to disease. TRUS guided intervention by means of biopsy or drainage can be performed with a rigid US probe as well as with flexible echoendoscopes. The rigid US probe with an end-fire design is optimal for endo-rectal interventions and in most cases can visualize the entire rectum including perirectal structures. With use of a dedicated needle guide mounted on the probe this technique enables precise puncture of most rectal or perirectal target seen on TRUS. TRUS guided biopsy of rectal masses is an important supplement to the conventional endoscopic biopsy if the latter technique does not provide the final diagnosis. Indications are staging of rectal cancer or suspicions of local recurrence. In these cases, a TRUS guided biopsy of the rectal masse with a 1.2 mm needle (18 gauge automatic or semi-automatic biopsy systems) can provide a deep tissue sample that often results in a final histologic diagnosis. In addition, TRUS guided biopsy is an obvious technique to provide histologic or cytologic information about enlarged lymph nodes or other suspicious perirectal masses. TRUS guided drainage of perianal and deep pelvis abscesses or other fluid collections is a safe approach and effective treatment in cases where the transabdominal percutaneous access cannot be utilized because of overlying structures. This technique provides an alternative to other access routes such as transvaginal, transgluteal or transperineal technique Smaller abscesses can often be treated with needle aspiration followed by saline irrigation, whereas larger abscesses may require continuous drainage through a catheter, which can be inserted with Seldinger technique. A preprocedure CT examination of the lower abdomen is recommended to visualize the exact location and size of the abscess in order to optimize drainage strategy.

The aim of this study was to demonstrate and evaluate the ultrasound-guided drainage of deep pelvic abscesses in which transabdominal percutaneous access could not be performed because of overlying structures. A retrospective analysis of 32 consecutive patients with 33 deep pelvic abscesses was performed. The underlying causes of the abscesses included postsurgical fluid collection or surgical complications in 18 of the 32 patients, and 11 of these patients underwent recent rectal cancer surgery. The locations of the abscesses, which had a median diameter of 6 cm (range 2-10 cm), were as follows: perirectal (n=13), presacral (n=9), pouch of Douglas (n=7), internal genitals (n=2) and between the bowel loops (n=2). The abscesses were all drained using ultrasound (US) guidance with a transrectal (n=18), transvaginal (n=11), transperineal ( n=2) or transgluteal (n=2) approach. Of the larger abscesses (median diameter 7 cm), 19 were treated with catheter drainage and 18 of these cases resulted in favorable clinical outcomes. Of the smaller abscesses (median diameter 4 cm), 14 were treated with needle drainage. In two of these cases, follow-up US showed that a repeat puncture and drainage was necessary. All needle drainages resulted in favorable clinical outcomes. Sixteen of the 29 transrectal or transvaginal drainage procedures were performed without any anesthesia (10 were performed with a needle and six were performed with a catheter). Apart from minor discomfort during the drainage procedure and the subsequent in-dwelling catheter period, there were no serious complications related to the drainage procedures. We conclude that ultrasound-guided transrectal, transvaginal, transperineal and transgluteal drainage of deep pelvic abscesses are safe and effective treatment approaches. Based on our findings, needle drainage will be our most common first-line treatment approach because of the simplicity of the procedure, improved patient comfort and reduced costs. Catheter drainage will be reserved for large multiloculated abscesses.

To quantify the border versus centre enhancement of malignant breast tumours on dynamic magnetic resonance mammography.Fifty-two women diagnosed with primary breast cancer underwent dynamic magnetic resonance mammography (Omniscan 0.2 mmol/kg bodyweight) on a midfield scanner (0.6 T), prior to surgery. The following five variables were recorded from the border and centre regions of the tumours: Early Enhancement, Time to Peak, Wash-in rate, Wash-out rate and Area under Curve. Information on histology type, oestrogen and progesterone receptor status was collected. Statistical analysis was performed in SAS 9.1 as paired samples t-tests.Fifty of 52 malignant tumours displayed a faster Early Enhancement in the border region compared to the centre (p0.0001). Significant differences between the border and centre values were found for Time to Peak, Wash-in rate, Wash-out rate and Area under Curve. Hormone receptor positive tumours displayed an over-all highly significant difference between border and centre enhancement, whereas no significant differences for any of the five variables were recorded in neither oestrogen nor progesterone hormone receptor negative tumours.The border/centre enhancement difference in malignant breast tumours is easily visualized on midfield dynamic magnetic resonance mammography. The dynamic behaviour is significantly correlated to histological features and receptor status of the tumours.

Rationale and Objectives. Radiofrequency (RF) tissue ablation with a cooled needle electrode (probe) can produce large lesions. By using this technique on ex vivo calf livers, the authors evaluated the role of ultrasound (US), dose response, and temperature course with time. Methods. RF ablation was produced with a 14-gauge probe with a 2-cm exposed tip. The lesions were examined with US and macroscopically after various treatment durations. Tissue temperature was measured with thermosensors inserted 1, 2, and 3 cm from the probe. Results. Before treatment the tip of the probe was easy to visualize with US, but during treatment microbubbles obscured the lesion and probe. After treatment, the lesions appeared hypoechoic. Lesion size was underestimated based on US findings. Lesion size was logarithmically correlated to treatment duration. Lesion temperature increased at an increased rate with higher wattage applied and with decreased distance from the probe. Conclusion. US is useful for probe placement before treatment and might be of value after treatment. Lesion size increases reproducibly with treatment duration.

Phytohemagglutinin (PHA)-induced colony formation in semisolid agar medium by human peripheral blood T lymphocytes showed an increasing cloning efficiency with decreasing numbers of cultured cells. Ninety percent of CD4 + cells (inducer/helper phenotype) and 20% of CD8 + cells (cytotoxic/suppressor phenotype) formed colonies when cultured at 10–200 cells/ml culture in the presence of sheep red blood cells (SRBC) and a source of interleukin-2 (IL-2). Probably all T-colony-forming cells, but none of the subsequent colony cells, expressed the Leu-8 antigen. The cloning efficiencies of FACS-sorted cells expressing the natural killer antigenic phenotypes Leu-7 + and CD16 + were found to be less than 1%. The costimulatory effect of red blood cells for colony formation was specific for SRBC and not observed in the presence of red cells obtained from seven other species including man. All T-lymphocyte colonies obtained from unseparated peripheral blood mononuclear cells expressed the CD25 antigen (IL-2 receptor) and colonies were always composed of either CD4 + or CD8 + cells. None of the colony cells expressed the Leu-8 or the CD16 antigens. By their specific morphology in agar culture the majority of colonies composed of CD4 + cells were easily recognized, but approximately one-third of the CD4 + colonies could not be distinguished from colonies composed of CD8 + cells. On expansion of individual colonies in liquid subculture in the presence of interleukin-2, approximately 15% of the colonies developed natural killer (NK)-like cytotoxic activity, being capable of direct killing of K562 tumor cells. It is concluded that the present method for growing human T colonies exhibits the same cloning efficiency as the most efficient liquid culture systems. Individual T colonies are composed exclusively of T inducer/helper or T cytotoxic/suppressor cells, they are never of mixed phenotype, and they do not contain cells of natural killer phenotype. Regulatory mechanisms influencing colony formation are operating between and within the various subsets of T lymphocytes.