Patients with severe polytrauma: management and imaging protocols.

Traumatic injuries can be severe and complex, requiring the coordinated efforts of a multidisciplinary team. Imaging tests play a fundamental role in rapid and accurate diagnosis. In particular, whole-body computed tomography (CT) has become a key tool. There are different CT protocols depending on the patient's condition; whereas dose-optimized protocols can be used in stable patients, time/precision protocols prioritizing speed at the cost of delivering higher doses of radiation should be used in more severe patients. In unstable patients who cannot be examined by CT, X-rays of the chest and pelvis and FAST or e-FAST ultrasound studies, although less sensitive than CT, enable the detection of situations that require immediate treatment. This article reviews the imaging techniques and CT protocols for the initial hospital workup for patients with multiple trauma.

Update on acute appendicitis: Typical and untypical findings.

Acute appendicitis is the most common indication for emergency abdominal surgery throughout the world and a common reason for consultation in emergency departments. In recent decades, diagnostic imaging has played a fundamental role in identifying acute appendicitis, helping to reduce the rate of blind laparotomies and hospital costs. Given the results of clinical trials supporting the use of antibiotic therapy over surgical treatment, radiologists need to know the diagnostic criteria for complicated acute appendicitis to be able to recommend the best treatment option. This review aims not only to define the diagnostic criteria for appendicitis in different imaging modalities (ultrasonography, computed tomography, and magnetic resonance imaging), but also to explain the diagnostic protocols, atypical presentations, and other conditions that can mimic appendicitis.

The usefulness and positive predictive value of ultrasonography and computed tomography in the diagnosis of acute appendicitis in adults: A retrospective study.

OBJECTIVE: To analyze the evolution of the use of imaging tests (ultrasonography and computed tomography (CT)) in the diagnosis of acute appendicitis. To determine the positive predictive value of these tests and the percentage of negative and complicated appendectomies. MATERIAL AND METHODS: This retrospective study compared adults who underwent appendectomy for suspected acute appendicitis at our tertiary hospital during 2015 versus similar patients at our center during 2007. RESULTS: A total of 278patients were included. The rate of negative appendectomies descended to 5%. The positive predictive value of ultrasonography increased to 97.4% in 2015, and the positive predictive value of CT and combined CT and ultrasonography was 100%. The rate of complicated appendicitis increased (23% in 2015). CONCLUSIONS: The use of imaging tests increased, and the rate of "blind" laparotomies decreased. Nevertheless, the rate of complicated appendicitis increased.

Radiologic diagnosis of patients with COVID-19. / Diagnóstico radiológico del paciente con COVID-19.

The pandemia caused by the SARS-CoV-2 virus has triggered an unprecedented health and economic crisis. Although the diagnosis of infection with SARS-CoV-2 is microbiological, imaging techniques play an important role in supporting the diagnosis, grading the severity of disease, guiding treatment, detecting complications, and evaluating the response to treatment. The lungs are the main organ involved, and chest X-rays, whether obtained in conventional X-ray suites or with portable units, are the first-line imaging test because they are widely available and economical. Chest CT is more sensitive than plain chest X-rays, and CT studies make it possible to identify complications in addition to pulmonary involvement, as well as to suggestive alternative diagnoses. The most common radiologic findings in COVID-19 are airspace opacities (consolidations and/or ground-glass opacities), which are typically bilateral, peripheral, and located primarily in the lower fields.

Pulmonary embolisms in patients with COVID-19: a prevalence study in a tertiary hospital. / Tromboembolismo pulmonar en pacientes con COVID-19: estudio de prevalencia en un hospital terciario.

INTRODUCTION: SARS-CoV-2, the virus responsible for the current pandemic, predominantly affects the respiratory tract, and a growing number of publications report the predisposition of patients with COVID-19 to develop thrombotic phenomena. OBJECTIVE: To determine the prevalence of pulmonary embolism in patients with COVID-19; to determine the possible relationship between the severity of pulmonary involvement and D-dimer levels; to analyze the location of pulmonary embolisms in patients with COVID-19 and to compare it with the location in patients without COVID-19. METHODS: This retrospective study analyzed all CT angiograms of the pulmonary arteries done in patients with suspected pulmonary embolisms between March 15 and April 30, 2020 and compared them with studies done in the same period one year earlier. RESULTS: We included 492 pulmonary CT angiograms (342 (69.9%) in patients with COVID-19 and 147 (30.1%) in patients without COVID-19). The prevalence of pulmonary embolisms was higher in patients with COVID-19 (26% vs. 16.3% in patients without COVID-19, p=0.0197; relative risk=1.6). The prevalence of pulmonary embolisms in the same period in 2019 was 13.2%, similar to that of the group of COVID-19-negative patients in 2020 (p=0.43). There were no significant differences in D-dimer levels or the location of pulmonary embolisms between the two groups. CT showed moderate or severe pulmonary involvement in 78.7% of the patients with COVID-19. CONCLUSIONS: Patients with COVID-19 have an increased prevalence of pulmonary embolisms (26%), and most (78.7%) have moderate or severe lung involvement on CT studies. The location of pulmonary embolisms and the degree of elevation of D-dimer levels does not differ between patients with COVID-19 and those without.

Puerperal complications: pathophysiological mechanisms and main imaging findings. / Complicaciones del puerperio: mecanismos fisiopatológicos y principales hallazgos radiológicos asociados.

OBJECTIVE: Puerperium is the period during which the physiological changes that have taken place during pregnancy revert and the uterus involutes until it reaches its normal size. This is a period of intense systemic changes, and diagnosing complications in this period is a challenge for both gynecologists and radiologists. This paper reviews the complications that can occur during puerperium, classifying them according to the pathophysiological mechanisms involved: the prothrombotic state, hemodynamic and hormonal changes, rapid uterine growth, changes associated with endothelial damage (preeclampsia, eclampsia, and HELLP syndrome), and postoperative complications in patients undergoing cesarean sections. CONCLUSION: Puerperal complications represent a diagnostic challenge. Understanding the pathophysiological mechanisms underlying these complications is fundamental for choosing the most appropriate imaging technique to ensure the correct diagnosis in each case.

The usefulness and positive predictive value of ultrasonography and computed tomography in the diagnosis of acute appendicitis in adults: a retrospective study. / Estudio retrospectivo y comparativo de la utilidad y del valor predictivo positivo de la ecografía y la tomografía computarizada en el diagnóstico de apendicitis aguda en adultos.

OBJECTIVE: To analyze the evolution of the use of imaging tests (ultrasonography and computed tomography (CT)) in the diagnosis of acute appendicitis. To determine the positive predictive value of these tests and the percentage of negative and complicated appendectomies. MATERIAL AND METHODS: This retrospective study compared adults who underwent appendectomy for suspected acute appendicitis at our tertiary hospital during 2015 versus similar patients at our center during 2007. RESULTS: A total of 278 patients were included. The rate of negative appendectomies descended to 5%. The positive predictive value of ultrasonography increased to 97.4% in 2015, and the positive predictive value of CT and combined CT and ultrasonography was 100%. The rate of complicated appendicitis increased (23% in 2015). CONCLUSIONS: The use of imaging tests increased, and the rate of "blind" laparotomies decreased. Nevertheless, the rate of complicated appendicitis increased.

Aortoenteric fistulas: spectrum of MDCT findings. / Fístula aortoentérica: Espectro de hallazgos en tomografía computarizada multidetector.

An aortoenteric fistula is an abnormal communication between the aorta and the gastrointestinal tract wall. The high mortality associated with this rare entity means it requires early accurate diagnosis. Aortoenteric fistulas are classified as primary when they develop on a native aorta that has not undergone an intervention and as secondary when they develop after vascular repair surgery. All radiologists need to be able to recognize the direct and indirect signs that might suggest the presence of an aortoenteric fistula. This article reviews the types of aortoenteric fistulas and their clinical and pathophysiological correlation, as well as the diagnostic algorithm, illustrating the most characteristic findings on multidetector computed tomography.

Necrotizing external otitis caused by Aspergillus fumigatus: computed tomography and high resolution magnetic resonance imaging in an AIDS patient.

Most necrotizing (malignant) external otitis (NEO) occurs in diabetic patients and is commonly caused by Pseudomonas aeruginosa. We report an acquired immunodeficiency syndrome (AIDS) patient with NEO caused by Aspergillus fumigatus in which computed tomography (CT) showed destructive petrous bone involvement and magnetic resonance imaging (MRI) of the ear discovered extensive soft tissue and facial nerve involvement. Dedicated MRI studies of the ear in this type of pathology provide new insights relating to nerve dysfunction, that cannot be obtained with CT.