Is there a role for CT in the neonate?

Choice of imaging modalities should be based on scientific proof and best practice guidelines. However, in the neonatal age group there is a paucity of medical evidence, and imaging is often guided by local experience, availability of equipment and expertise, and by logistical factors. This paper discusses possible indications for CT in the neonate, the associated radiation protection issues, common CT findings and potential pitfalls in technique and image interpretation. Due to the particular range of abnormalities in this age group, imaging must be tailored to the individual, and should in most cases be done in specialist units.     

Hip replacement in the athlete: is there a role?

Sport and total hip arthroplasty (THA) have been regarded by many as being mutually exclusive. The primary indication for hip arthroplasty has always been pain. With advances in the technology surrounding hip replacement surgery and increasing patient expectations of what THA can offer, there is a growing demand for hip replacement with the aim of returning to sporting activity. The aim of this review article is to report the advances in hip replacement surgery that aim to make the procedure more suitable for the sporting individual and to summarise the literature on the subject of returning to sports after THA.     

Intravenous glucagon: does it optimize evaluation of the gastrointestinal tract on helical CT?

Forty outpatients were randomized into two groups of 20. Twenty patients received 1 mg of intravenous glucagon and the other 20 did not. Three radiologists evaluated the bowel using a qualitative score and mean scores for each bowel level were compared. A different radiologist measured the maximal diameter of bowel at seven levels. There were no significant differences in qualitative or quantitative data for the two groups. Intravenous glucagon is therefore not routinely recommended for helical CT of the abdomen.     

What is the role of plain radiography in patients with foreign bodies in the gastrointestinal tract?

Foreign bodies (FBs) in the gastrointestinal (GI) tract can show a wide range of clinical manifestations ranging from spontaneous evacuation to severe complication. Plain radiography is a straightforward and important initial imaging modality in cases of FB ingestion or insertion and is also helpful for follow-up purposes. Careful evaluations of the plain radiographs can determine the presence and nature of FBs, and help predict their precise locations and facilitate risk assessment. In this review, a wide variety of FBs in the GI tract are illustrated, and the role of plain radiography in patient management is discussed.     

Non-cutaneous melanoma: is there a role for 18F-FDG PET-CT?

Non-cutaneous melanomas (NCM) are diverse and relatively uncommon. They often differ from cutaneous melanomas in their epidemiology, genetic profile and biological behaviour. Despite the growing body of evidence regarding the utility of positron emission tomography (PET)/CT in cutaneous melanoma, the data on its use in NCM are scarce. In this review, we will summarize the existing literature and present cases from our experience with NCM to illustrate current knowledge on the potential role and limitations of fluorine-18 fludeoxyglucose PET/CT in NCM.Non-cutaneous melanomas (NCM) are classified according to origin: ocular, mucosal or unknown primary. Ocular melanomas may arise from the uvea or conjunctiva. Mucosal melanomas may originate from mucosal surfaces in the head and neck (oral cavity, nasal and paranasal sinuses) and gastrointestinal and genitourinary tracts. NCM are relatively rare, with ocular and mucosal melanomas accounting for only 5.5% and 1.3% of all melanomas in North America, respectively. The incidence of mucosal melanoma may vary according to the population studied (range, 0.2–10.0%) and is higher in Asian populations. By contrast, uveal melanomas are more common in Caucasians. 1,2 Staging and management of NCM varies by location and differs from cutaneous melanoma. In NCM, primary therapy consists of local resection, often with adjuvant radiotherapy. There may be a role for chemotherapy and immunotherapy; however, this approach has largely been extrapolated from experience with cutaneous tumours.

Table 1.

Comparison of cutaneous and non-cutaneous melanoma^1,2

Blunt bowel and mesenteric trauma: role of clinical signs along with CT findings in patients’ management

Background

Bowel and/or mesentery injuries represent the third most common injury among patients with blunt abdominal trauma. Delayed diagnosis increases morbidity and mortality. The aim of our study was to evaluate the role of clinical signs along with CT findings as predictors of early surgical repair.

Material and methods

Between March 2014 and February 2017, charts and CT scans of consecutive patients treated for blunt abdominal trauma in two different trauma centers were reread by two experienced radiologists. We included all adult patients who underwent contrast-enhanced CT of the abdomen and pelvis with CT findings of blunt bowel and/or mesenteric injury (BBMI). We divided CT findings into two groups: the first included three highly specific CT signs and the second included six less specific CT signs indicated as “minor CT findings.” The presence of abdominal guarding and/or abdominal pain was considered as “clinical signs.” Reference standards included surgically proven BBMI and clinical follow-up. Association was evaluated by the chi-square test. A logistic regression model was used to estimate odds ratio (OR) and confidence intervals (CI).

Results

Thirty-four (4.1%) out of 831 patients who sustained blunt abdominal trauma had BBMI at CT. Twenty-one out of thirty-four patients (61.8%) underwent surgical repair; the remaining 13 were treated conservatively. Free fluid had a significant statistical association with surgery (p?=?0.0044). The presence of three or more minor CT findings was statistically associated with surgery (OR?=?8.1; 95% CI, 1.2–53.7). Abdominal guarding along with bowel wall discontinuity and extraluminal air had the highest positive predictive value (100 and 83.3%, respectively).

Conclusion

In patients without solid organ injury (SOI), the presence of free fluid along with abdominal guarding and three or more “minor CT findings” is a significant predictor of early surgical repair. The association of bowel wall discontinuity with extraluminal air warrants exploratory laparotomy.

     

Radiological assessment of mesenteric and retroperitoneal cysts in adults: is there a role for chemical shift MRI?

Objective

The purpose of this study was to assess the potential role for chemical shift magnetic resonance imaging (MRI) in identifying lymphangiomas from other cystic mesenteric and retroperitoneal masses.

Materials and methods

A retrospective search of radiology database identified 24 consecutive patients with mesenteric and retroperitoneal cysts (nine men, 15 women; mean age, 41 years; age range, 19-75 years) who had undergone MR which included in-phase and opposed-phase chemical shift imaging. Signal intensity (SI) decrease between in-phase and opposed-phase MR images of the cyst was evaluated qualitatively by two radiologists. Ultrasound (US), computed tomography (CT), and MRI findings of the morphological appearances of all the cystic lesions that demonstrated significant signal drop on chemical shift MR were also recorded.

Results

Of mesenteric and retroperitoneal cysts, 33% (8/24) revealed qualitative decrease in intensity on opposed-phase MR images relative to that seen on in-phase images. On ultrasound, these cysts demonstrated anechoic simple fluid. Their mean CT attenuation was 13 HU (range: 5-20 HU). Signal loss on fat-suppressed T1-weighted sequences was displayed only by a single cyst. None of the lesions with qualitative SI decrease on opposed-phase MR showed suggestion of lipid on US and CT.

Conclusion

The presence of intra cystic lipid detected by chemical shift MR may not be overt on cross-sectional imaging such as US and CT. Chemical shift MRI provides additional sensitivity and specificity as an imaging test for demonstration of lipid within mesenteric and retroperitoneal cysts enabling a higher diagnostic yield for lymphangioma leading to more appropriate patient management.     

Is there a role for exercise in the prevention of osteoporotic fractures?

OBJECTIVES: To examine whether there is a role for exercise in improving bone mineral density (BMD), particularly in postmenopausal women. The effects of different types of exercise are examined together with their effects at selected skeletal sites. The role of activity in reducing falls and hip fractures will also be considered as well as the potentially negative effects of excessive exercise. METHODS: A literature search over the past 20 years was conducted and landmark papers selected. RESULTS: Certain types of exercise have been found to exert moderate benefits on BMD of the wrist, spine, and hip. Most studies do not detect a difference between the effects of endurance activities and strength training for BMD of the spine. It has been more difficult to isolate the optimal type of activity for effecting an osteogenic response at the hip, but recent evidence suggests that high impact work such as stepping and jumping may be effective at this site. The combination of hormone replacement therapy and exercise would appear to be more effective than either intervention on its own. Certain types of exercises have additional benefits, such as muscle strengthening, which could reduce the incidence of falls. Excessive exercise can lead to menstrual disturbances in female athletes and this in turn can cause bone loss, particularly from the spine. CONCLUSIONS: Exercise across the life span should be encouraged in order to maximise peak bone mass, reduce age related bone loss, and maintain muscle strength and balance. Although the effects of exercise on BMD later in life are small, epidemiological evidence suggests that being active can nearly halve the incidence of hip fractures in the older population. This effect is most probably multifactorial through the positive effects on bone, muscle strength, balance, and joint flexibility. Younger women should be aware of the dangers to the skeleton of menstrual disorders.     

MDCT of abdominal wall hernias: is there a role for valsalva's maneuver?

OBJECTIVE: Our objective was to evaluate the role of Valsalva's maneuver during MDCT for the diagnosis and characterization of abdominal wall hernias. SUBJECTS AND METHODS: From September 2002 to May 2003, 100 consecutive patients (37 men and 63 women; mean age, 53 years) with suspected anterior abdominal wall hernias underwent 4-, 8-, or 16-MDCT with and without Valsalva's maneuver. Patients received both oral and IV contrast material. On a workstation, three independent reviewers evaluated each scan obtained during rest and during Valsalva's maneuver for the following parameters: anteroposterior (AP) diameter of the abdomen; presence, location, and contents of the hernia; and transverse diameter of the fascial defect. The scans were compared to assess for changes in hernia size and contents and to determine whether the hernia would have been overlooked without Valsalva's maneuver. Fisher's exact test, the McNemar test, and Cohen's kappa coefficient were used to assess for significant differences. RESULTS: The three reviewers identified a mean of 72 abdominal wall hernias (72%). The reviewers agreed (kappa = 0.723) with respect to the presence of a hernia. AP diameters increased an average of 1.33 cm during Valsalva's maneuver (p < 0.001). The transverse diameter of the fascial defect increased an average of 0.66 cm and the AP diameter of the hernia sac increased an average of 0.79 cm during Valsalva's maneuver (p < 0.001). Fifty percent of the hernias became more apparent with Valsalva's maneuver. Ten percent of the hernias could be detected only on the scan obtained during Valsalva's maneuver. Conversely, in no patients was the hernia detected only on the rest scan. CONCLUSION: As opposed to scans obtained at rest, scans obtained during Valsalva's maneuver aid in the detection and characterization of suspected abdominal wall hernias. A single scan obtained during Valsalva's maneuver is sufficient to detect 100% of anterior abdominal wall hernias identified on CT.     

Palpable breast masses: is there a role for percutaneous imaging-guided core biopsy?

OBJECTIVE: The purpose of this study was to evaluate percutaneous imaging-guided core biopsy in the assessment of selected palpable breast masses. MATERIALS AND METHODS: Of 1388 consecutive breast lesions that had percutaneous imaging-guided core biopsy, 155 (11%) were palpable. Palpable masses referred for percutaneous imaging-guided core biopsy included lesions that were small, deep, mobile, vaguely palpable, or multiple. Biopsy guidance was sonography in 140 lesions (90%) and stereotaxis in 15 (10%). Surgical correlation or minimum of 2 years follow-up is available in 115 palpable masses in 107 women. Medical records, imaging studies, and histologic findings were reviewed. RESULTS: Of 115 palpable breast masses, 98 (85%) were referred by surgeons to the radiology department for percutaneous imaging-guided core biopsy and 88 (77%) had percutaneous imaging-guided core biopsy on the day of initial evaluation at our institution. Percutaneous imaging-guided core biopsy spared additional diagnostic tissue sampling in 79 (74%) of 107 women, including 57 women with carcinoma and 22 women with benign findings. Percutaneous imaging-guided core biopsy did not spare additional tissue sampling in 28 women (26%), including 15 women in whom surgical biopsy was recommended on the basis of percutaneous biopsy findings and 13 women with benign (n = 7) or malignant (n = 6) percutaneous biopsy findings who chose to undergo diagnostic surgical biopsy. CONCLUSION: Percutaneous imaging-guided core biopsy is useful in the evaluation of palpable breast masses that are small, deep, mobile, vaguely palpable, or multiple. In this study, percutaneous imaging-guided core biopsy spared additional diagnostic tissue sampling in 74% women with palpable breast masses.     

Science in the courtroom: is there,and should there,be a better way?

Abstract

Justice Stephen Breyer of the US Supreme Court once wrote: ’In this age of science, science should expect to find a warm welcome, perhaps a permanent home, in our courtrooms… Our decisions should reflect a proper scientific and technical understanding so that the law can respond to the needs of the public.’ That was nearly two decades ago. The ‘welcome’ science receives in our courtrooms has been at times controversial for at least a century, if not more, and is still problematic, difficult and often contentious. Balancing the victim’s and the community’s interest in the detection and punishment of crime, the defendant’s right to a fair trial, and the state’s interest in a fair, accessible and just judicial system, all make the entry of the world of science in our courtrooms, and the use of science by fact-finders and tribunals, a fundamental and continuing question that needs continually to be addressed and answered in our courts. As another American Judge once said: ‘You are going to be playing in my ballpark and by my rules …’. Is there, and should there, be a better way?