Ultra-High-Frequency Ultrasound: A Modern Diagnostic Technique for Studying Melanoma. / Ultrahochfrequenz-Ultraschall: Eine moderne Diagnosetechnik zur Untersuchung von Melanomen.

The development of new ultra-high-frequency devices with a resolution of 30 µm makes it possible to use ultrasound in the study of new small anatomical units and to apply this tool to new fields of pathology. Cutaneous melanoma is a severe skin disease with an incidence of approximately 160 000 new cases each year and 48 000 deaths. In this paper, we evaluate the role of HFUS in the diagnosis of cutaneous melanoma, describe the sonographic appearance of skin layers in the pre-excision phase as well as of lesion features, and correlate the characteristics with pathological examination.

Bone fractures difficult to recognize in emergency: May be cone beam computed tomography (CBCT) the solution?

CBCT is an imaging tool represented by an X-ray computed tomography delivering a conic-shape X-rays source. This system produces volumetric data during a single rotation of both X-ray beam and detector around the stationary patient. CBCT is able to produce three-dimensional images as for MDCT, however, accounting some advantages over it: lower radiation dose, faster volumetric dataset acquisition, higher spatial resolution and bone contrast. For these reasons, CBCT has recently been described and adopted for extremities imaging in orthopedics. Misinterpretation of fractures may determine a delayed treatment and poor outcome for patients treated in the ED. CBCT, by easily identifying occult cortical fractures and using a lower dose of radiation, is proposed as an alternative or supplement to direct radiograms, optimizing the cost-effectiveness ratio and limiting the number of unnecessary immobilizations. The first experiences document excellent performance of CBCT in emergency radiology departments, especially thanks to transverse imaging in trauma of the extremities.

Clinical Application of Ultra-High-Frequency Ultrasound.

Musculoskeletal ultrasound involves the study of many superficial targets, especially in the hands, wrists, and feet. Many of these areas are within the first 3 cm of the skin surface and are ideal targets for ultra-high-frequency ultrasound. The high spatial resolution and the superb image quality achievable allow foreseeing a wider use of this novel technique, which has the potential to bring innovation to diagnostic imaging.

Large Bowel Ischemia/Infarction: How to Recognize It and Make Differential Diagnosis? A Review.

Ischemic colitis represents the most frequent form of intestinal ischemia occurring when there is an acute impairment or chronic reduction in the colonic blood supply, resulting in mucosal ulceration, inflammation, hemorrhage and ischemic necrosis of variable severity. The clinical presentation is variable and nonspecific, so it is often misdiagnosed. The most common etiology is hypoperfusion, almost always associated with generalized atherosclerotic disease. The severity ranges from localized and transient ischemia to transmural necrosis of the bowel wall, becoming a surgical emergency, with significant associated morbidity and mortality. The diagnosis is based on clinical, laboratory suspicion and radiological, endoscopic and histopathological findings. Among the radiological tests, enhanced-CT is the diagnostic investigation of choice. It allows us to make the diagnosis in an appropriate clinical setting, and to define the entity of the ischemia. MR may be adopted in the follow-up in patients with iodine allergy or renal dysfunctions, or younger patients who should avoid radiological exposure. In the majority of cases, supportive therapy is the only required treatment. In this article we review the pathophysiology and the imaging findings of ischemic colitis.

Percutaneous Radiofrequency Ablation of the Posterior and Anterior Interosseous Nerves for Chronic Wrist Pain: A Novel Technique.

The treatment of chronic wrist pain, due to posttraumatic, degenerative, or inflammatory arthritis, is challenging to adequately manage. The ideal surgical procedure should preserve wrist mobility and provide long-lasting pain relief. In this regard, denervation aims to decrease wrist pain by interrupting sensory innervation, without impairing motor function, and avoids the need for postoperative immobilization to decrease the risk of stiffness. For these reasons, denervation is particularly attractive as a possible treatment for chronic wrist pain. Our aim was to describe our novel technique for partial percutaneous wrist denervation, performed by radiofrequency ablation of the posterior and anterior interosseous nerves, and to report on the prospective outcomes over a 1-year follow-up for 3 patients (4 wrists) treated as of March 2019. The technique is performed on an outpatient basis and does not require postprocedure wrist immobilization or restriction in activities of daily living or work. Findings at the 1-year follow-up indicate that partial denervation improved grip strength, provided pain relief, maintained wrist motion, and improved subjective report of disabilities of the arm, shoulder, and hand. One patient did not report a benefit of the procedures, with other patients being very satisfied. Our percutaneous procedure is an evolution of the traditional partial denervation technique, providing advantages of being less invasive, not requiring restriction of movement or activities in the postoperative phase, can be performed on an out-patient basis, and does not preclude the subsequent use of invasive surgical procedures, as needed.

Pelvic floor dysfunctions: how to image patients?

Pelvic floor dysfunctions embrace a large series of different conditions in which functional abnormalities of the pelvic floor lead to impairment in urinary and sexual functions and in rectal voiding. A multidisciplinary approach is needed in the evaluation of these patients, as well as the adoption of imaging studies adequate to explore the complex anatomy of the region and its dynamic functionality. Available imaging studies include: endoanal and transperineal ultrasound, X-ray defecography and MR defecography. The purpose of this review article is to illustrate the technique, indications, the current role, and diagnostic value of each one of these. The recent availability of new imaging techniques and related advantages will also be discussed.

MDCT in acute ischaemic left colitis: a pictorial essay.

The pathogenesis of acute ischaemic colitis depends on two different forms of vascular colonic insult: occlusive injury and non-occlusive injury. Clinically, ischaemic colitis may be classified as two major forms: mild (non-gangrenous) and acute fulminant (gangrenous). The classic presentation is abdominal pain, diarrhoea and/or rectal bleeding, but it is not specific and highly variable and so the diagnosis usually depends on clinical suspicion and is supported by serologic and colonoscopic findings. Imaging methods have their role in diagnosing IC. While plain radiography and ultrasound can orient the diagnosis, CT allows to define the morphofunctional alterations discriminating the non-occlusive forms from the occlusive forms and in most cases to estimate the timing of ischaemic damage. Purpose of the review is to define the role of CT in the early identification of pathological findings and in the definition of evolution of colonic ischaemic lesions, in order to plan the correct therapeutic approach, suggesting the decision of medical or surgical treatment.

A rat model of acute kidney injury through systemic hypoperfusion evaluated by micro-US, color and PW-Doppler.

AIM: To create an animal model of acute renal ischemia induced by systemic hypoperfusion, controllable and reproducible to study, in real time, hemorrhagic shock changes with micro-imaging. ANIMALS AND METHODS: Hemorrhagic shock was induced in rats activating a syringe pump setup to remove 1 mL/min of blood, through the femoral artery catheter. The withdrawal was continued until the mean arterial pressure (MAP) dropped to 25-30 mmHg. For the next 60 min, the MAP was maintained at a constant pressure value, by automatic pump infusion and withdrawal. Micro-ultrasound imaging was performed using the Vevo 2100 system with the MS250 transducer (13-24 MHz). Renal size, morphology and echogenicity were evaluated in B-mode. Renal blood flow was evaluated using color and PW-Doppler. RESULTS: After 1 h of ischemia, B-mode images documented slight changes in kidney echogenicity. Color and PW-Doppler analysis showed a reduction in renal blood flow in kidneys during the hypoperfusion with a progressive and significant change from baseline values of resistive index (RI). At the histological evaluation, 60 min of hypoperfusion resulted in ischemic changes in the kidneys. CONCLUSIONS: The results of this experimental study encourage the use of the described model to study acute renal ischemia trough severe hypoperfusion. The histological data confirmed that the model was able to produce injury in renal parenchyma. It can be used to assess acute ischemic damage not only in the kidney but also in other organs by using all available dedicated small animals imaging techniques.

High resolution real time ultrasonography of the sural nerve after percutaneous repair of the Achilles tendon.

BACKGROUND: Percutaneous Achilles tendon repair has been developed to minimise soft tissue complications following treatment of tendon ruptures. However, there are concerns because of the risk of sural nerve injury. Few studies have investigated the relationship between the Achilles tendon, the sural nerve and its several anatomical course variants. METHODS: We studied 7 cadaveric limbs (7 Achilles tendons) in which a percutaneous repair of the Achilles tendon was performed. On each tendon, high resolution real time ultrasonography examination was performed by an experienced musculoskeletal radiologist before and after the procedure, with the surgeons blind to the results of the scan both before and after surgery. RESULTS: In two instances, high resolution real time ultrasonography examination revealed nerve entrapment at the level of most proximal lateral suture. CONCLUSIONS: Since the sural nerve can be easily visualised using high-frequency high resolution real time ultrasonography, intraoperative ultrasound can be of assistance during percutaneous repair of Achilles tendon rupture. CLINICAL RELEVANCE: The sural nerve can be readily visualised by high-frequency high resolution real time ultrasonography probes. It could be beneficial to use high resolution real time ultrasonography intraoperatively or perioperatively to minimise the risks of sural nerve injury when undertaking percutaneous repair of Achilles tendon tears.

Scapular fractures: a common diagnostic pitfall.

Scapular fractures are one of the most difficult fractures to diagnose on radiographs. Detection can be challenging because of the obscuration by the overlying structures or incomplete imaging due to difficult patient collaboration. Familiarity with imaging characteristics of these abnormalities will allow radiologists to better diagnose and characterize scapular fractures. Three-dimensional computed tomographic scans are considered the gold standard for scapular diagnoses. Treatment strategies differ depending on the type of scapular fractures, but the site and degree of displacement will determine whether surgical intervention should be considered. Complications can occur in fractures that are undiagnosed or improperly evaluated. The purpose of this article is to describe imaging features of traumatic scapular injury, and discuss the role of diagnostic imaging in clinical decision making after shoulder trauma.

Traumatic fractures in adults: missed diagnosis on plain radiographs in the Emergency Department.

Radiography remains the imaging standard for fracture detection after trauma. The radiographic diagnosis of most fractures and dislocations poses little difficulty to radiologists: however, occasionally these injuries are quite subtle or even impossible to detect on radiographs. Missed diagnoses of fracture potentially have important consequences for patients, clinicians, and radiologists. Radiologists play a pivot role in the diagnostic assessment of the trauma patients: emergency radiologists who are more practiced at seeking out and discerning traumatic fractures can provide an invaluable service to their clinical colleagues by ensuring that patients do not endure delayed diagnoses. This is a narrative review article aims to highlight the spectrum of fractures in adults potentially missed on plain radiographs, the causes of error in diagnosis of fractures in the emergency setting and the key elements to reduce misdiagnosis of fractures.

Ultra high-frequency ultrasound: New capabilities for nail anatomy exploration.

Recent development of ultra high-resolution ultrasound systems, with frequencies as high as 70 MHz and capability resolution as fine as 30 µm, could permit new diagnostic applications to small parts. A variety of superficial targets within the first 1 cm of the skin surface could be imaged, including dermatological applications such as assessment of skin layers, hair follicles and the nail unit. Nail disorders are frequent but they are diagnosed mainly based on clinical examination; although biopsies and scrapings can provide clinically significant information, most patients do not perceive biopsies positively. To image the skin layer and annexes is often difficult with conventional ultrasound but, because of anatomical details obtained with the newest systems, this method holds great promise for addressing important biomedical applications offering unique advantages over the existing non-invasive imaging modalities. This will enable physicians to assess and manage the conditions involving the nails of a large and growing segment of the population in a better way.

MDCT in ischaemic colitis: how to define the aetiology and acute, subacute and chronic phase of damage in the emergency setting.

Ischemic colitis (IC) is the most common vascular disorder of the gastrointestinal tract with a reported incidence of 6.1-44 cases/100,000 person years with confirmatory histopathology. However, the true incidence of IC poses some difficulty, and even vigilant clinicians with patients at high risk often miss the diagnosis, since clinical presentation is non-specific or could have a mild transient nature. Detection of IC results is crucial to plan the correct therapeutic approach and reduce the reported mortality rate (4-12%). Diagnosis of IC is based on a combination of clinical suspicion, radiological, endoscopic and histological findings. Some consider colonoscopy as a diagnostic test of choice; however, preparation is required and it is not without risk, above all in patients who are severely ill. There are two manifestations of vascular colonic insult: ischaemic and reperfusive. The first one occurs above all during ischaemic/non-occlusive mesenteric ischaemia; in this case, the colonic wall appears thinned with dilated lumen and fluid appears in the paracolic space. When reperfusion occurs, the large bowel wall appears thickened and stratified, because of subepithelial oedema and/or haemorrhage, with consequent lumen calibre reduction. Shaggy contour of the involved intestine and misty mesentery are associated with the pericolic fluid. The pericolic fluid results are a crucial finding for IC diagnosis since its evidence suggests the presence of an ongoing damage thus focusing the attention on other pathological aspects which could be otherwise misdiagnosed, such as thinned or thickened colonic wall. Moreover, the pericolic fluid may increase or decrease, depending on the evolution of the ischaemic damage, suggesting the decision of medical or surgical treatment. Radiologists should not forget the hypothesis of IC, being aware that multidetector CT could be sufficient to suggest the diagnosis of IC, allowing for early identification and grading definition, and in a short-term follow-up, discriminating patients who need urgent surgery from patients in whom medical treatment and follow-up can be proposed.

Harmonic technology versus neodymium-doped yttrium aluminium garnet laser and electrocautery for lung metastasectomy: an experimental study.

OBJECTIVES: We compared the efficacy of non-anatomical lung resections with that of three other techniques: monopolar electrocautery; neodymium-doped yttrium aluminium garnet laser and harmonic technology. We hypothesized that the thermal damage with harmonic technology could be reduced because of the lower temperatures generated by harmonic technology compared with that of other devices. METHODS: Initial studies were performed in 13 isolated pig lungs for each group. A 1.5-cm capsule was inserted within the lung to mimic a tumour and a total of 25 non-anatomical resections were performed with each device. The damage of the resected lung surface and of the tumour border were evaluated according to the colour (ranging from 0-pink colour to 4-black colour), histological (ranging from Score 0-no changes to Score 3-presence of necrotic tissue) and radiological (ranging from Score 0-isointense T2 signal at magnetic resonance imaging to Score 3-hyperintense T2 signal) criteria. A total of seven non-anatomical resections with harmonic technology were also performed in two live pigs to assess if ex vivo results could be reproducible in live pigs with particular attention to haemostatic and air-tightness properties. RESULTS: In the ex vivo lung, there was a statistical significant difference between depth of thermal damage (P < 0.0001) in electrocautery (1.3 [1.2-1.4]), laser (0.9 [0.6-0.9]) and harmonic (0.4 [0.3-0.5]) groups. Electrocautery had a higher depth of thermal damage compared with that of the laser (P = 0.01) and harmonic groups (P = 0.0005). The harmonic group had a less depth of thermal damage than that of the laser group (P = 0.01). Also, histological damages of tumour borders (P < 0.001) and resected lung surface (P < 0.001), radiological damage of tumour borders (P < 0.001) and resected lung surface (P < 0.001) and colour changes (P < 0.001) were statistically different between three study groups. Resections of in vivo pig lungs showed no bleeding; 2 of 7 cases of low air leaks were found; however, they ceased by sealing lung parenchyma with harmonic technology. CONCLUSIONS: Our experimental data support the resections performed with the use of harmonic technology. The lack of severe tissue alterations could favour healing of parenchyma, assure air tightness and preserve functional lung parenchyma. However, randomized controlled studies are needed in an in vivo model to corroborate our findings.

Reperfusion in non-occlusive mesenteric ischaemia (NOMI): effectiveness of CT in an emergency setting.

OBJECTIVE: To investigate the CT features of reperfusion (presence/absence) in non-occlusive mesenteric ischaemia (NOMI) and their prognostic value in an emergency setting. METHODS: A revision was undertaken of imaging from 20 patients (16 males/4 females) with a dismissal summary of NOMI. All patients had previously undergone a minimum of one multidetector CT examination, and consequently underwent surgery (n = 8), autopsy (n = 2), angiography (n = 1) or endoscopy (n = 9). An evaluation of the CT scans was conducted to determine vessels, mesentery, bowel and peritoneal cavity features. The superior mesenteric artery (SMA) average diameter of NOMI cases were compared with 30 controlled cases. Kappa, Kolmogorov-Smirnov (K-S) and Fisher's exact tests were used for statistical analysis. RESULTS: A mean SMA diameter significantly smaller than that of the controlled cases was found for patients with NOMI (K-S test: D = 0.75, p = 3.7 × 10-08). Fisher's exact tests showed a strong connection between the presence of reperfusion and mesenteric fat stranding (p = 0.026), bowel wall thickening (p = 3.2 × 10-05) and a high attenuation of the bowel wall on unenhanced CT images (p = 2.8 × 10-04). A reduction in mortality was significantly linked to the combination of normal mesenteric vessels and wall thickening (p = 0.034). CONCLUSION: Analysis of not only vessels findings but also mesentery and bowel CT features will support the identification of NOMI with or without a reperfusion event in an emergency setting. A strong correlation between some CT features and lower mortality exists. ADVANCES IN KNOWLEDGE: CT features of NOMI with or without reperfusion are demonstrated. Correctly assessing the presence of reperfusion in NOMI, may allow better management of these conditions in the emergency setting.

Imaging Patients With Alimentary Tract Perforation: Literature Review.

Alimentary tract perforation is a frequent emergency condition. Imaging plays an important role to make an accurate diagnosis, defining the presence, the level, and the cause of the perforation, essential information to enable the most correct therapeutic choice. Plain radiography is generally performed as the first choice. In case of a clinically suspected bowel perforation, not detected on x-ray imaging, the contribution of computed tomography is essential. Magnetic resonance is not yet widely used in diagnostic workup of patients with acute abdominal pain, but it can be useful in the differential diagnosis of acute abdomen in specific patients (pregnancy and pediatric patients).

Small-Bowel Neoplasms: Role of MRI Enteroclysis.

Small-bowel neoplasms are the 3%-6% of all gastrointestinal tract neoplasms. Due to the rarity of these lesions, the low index of clinical suspicion, and the inadequate radiologic examinations or incorrect interpretation of radiologic findings, a delay in diagnosis of 6-8 months from the first symptoms often occurs. Even if conventional enteroclysis and capsule endoscopy are the most common procedures used to accurately depict the bowel lumen and mucosal surface, their use in evaluating the mural and extramural extents of small-bowel tumors is limited. Instead multidetector computed tomographic enteroclysis and magnetic resonance enteroclysis have the potential to simultaneously depict intraluminal, mural, and extraintestinal abnormalities. In particular MR enteroclysis has an excellent soft tissue contrast resolution and multiplanar imaging capability. It can provide anatomic, functional, and real time information without the need of ionizing radiation. MR findings, appearances of the lesions, combined with the contrast-enhancement behavior and characteristic of the stenosis are important to differentiate small-bowel neoplasm from other nonneoplastic diseases.

Bowel intussusceptions in adults: the role of imaging.

Intestinal intussusception in adults is a rare condition, accounting for about 0.003-0.02% of all hospital admissions. This condition in adults represents only 5% of all cases of intussusceptions and is different from paediatric intussusception, which is usually idiopathic. In contrast, almost 90% of cases in adults are secondary to various pathologies that serve as a lead point, such as polyps, Meckel's diverticulum, colonic diverticulum, or malignant or benign neoplasm. The aim of the present study was to assess the capabilities of multislice computed tomography (MSCT) in the diagnosis and correct characterisation of intussusception, especially in distinguishing between intussusceptions with a lead point and those without. Indeed, although the MSCT findings that help to differentiate between lead point and non-lead point intussusceptions have not been well studied, abdominal MSCT remains the most sensitive radiological tool to confirm bowel intussusceptions. Moreover, differentiating intussusceptions with a lead point condition from those without is crucial for directing the patient towards the most appropriate treatment, avoiding surgery when not necessary.