Francesca Laghi

Imaging of stone disease in pregnancy

Renal colic is the most frequent non-obstetric cause for abdominal pain and subsequent hospitalization during pregnancy. Intervention is necessary in patients who do not respond to conservative treatment. Ultrasound (US) is widely used as the first-line diagnostic test in pregnant women with nephrolithiasis, despite it is highly nonspecific and may be unable to differentiate between ureteral obstruction secondary to calculi and physiologic hydronephrosis. Magnetic resonance imaging (MRI) should be considered as a second-line test, when US fails to establish a diagnosis and there are continued symptoms despite conservative management. Moreover, MRI is able to differentiate physiologic from pathologic dilatation. In fact in the cases of obstruction secondary to calculi, there is renal enlargement and perinephric edema, not seen with physiological dilatation. In the latter, there is smooth tapering of the middle third of the ureter because of the mass effect between the uterus and adjacent retroperitoneal musculature. When the stone is lodged in the lower ureter, a standing column of dilated ureter is seen below this physiological constriction. MRI is also helpful in demonstrating complications such as pyelonephritis. In the unresolved cases, Computed tomography remains a reliable technique for depicting obstructing urinary tract calculi in pregnant women, but it involves ionizing radiation. Nephrolithiasis during pregnancy requires a collaboration between urologists, obstetricians, and radiologists.

Imaging for acute pelvic pain in pregnancy

AbstractAcute pelvic pain in pregnancy presents diagnostic and therapeutic challenges. Standard imaging techniques need to be adapted to reduce harm to the foetus from X-rays because of their teratogenic and carcinogenic potential. Ultrasound remains the primary imaging investigation of the pregnant abdomen. Magnetic resonance imaging (MRI) has been shown to be useful in the diagnosis of gynaecological and obstetric problems during pregnancy and in the setting of acute abdomen during pregnancy. MRI overcomes some of the limitations of ultrasound, mainly the size of the gravid uterus. MRI poses theoretical risks to the foetus and care must be taken to minimise these with the avoidance of contrast agents. Teaching Points • Ultrasound and MRI are the preferred investigations for acute pelvic pain during pregnancy.• Ultrasound remains the primary imaging investigation because of availability and portability.• MRI helps differentiate causes of acute pelvic pain when ultrasound is inconclusive.

Magnetic resonance imaging of small bowel neoplasms.

Abstract Magnetic resonance (MR) imaging is rapidly increasing clinical acceptance to evaluate the small bowel and can be the initial imaging method to investigate small bowel diseases. MR examinations may provide the first opportunity to detect and characterize tumours of the small bowel. Intra- and extraluminal MR findings, combined with contrast enhancement and functional information, help to make an accurate diagnosis and consequently characterize small bowel neoplasms. MR enteroclysis should be recommended for the initial investigation in patients suspected of having small bowel tumours. In this article, the MR findings of primary small bowel neoplasms are described and the MR findings for the differential diagnosis are discussed.

Stone disease in pregnancy: imaging-guided therapy

AbstractRenal colic is the most frequent nonobstetric cause for abdominal pain and subsequent hospitalization during pregnancy. The physio-anatomical changes in the urinary tract and the presence of the fetus may complicate the clinical presentation and management of nephrolithiasis. Ultrasound (US) is the primary radiological investigation of choice. Magnetic resonance urography (MRU) and low-dose computed tomography (CT) have to be considered as a second- and third-line test, respectively. If a study that uses ionizing radiation has to be performed, the radiation dose to the fetus should be as low as possible. The initial management of symptomatic ureteric stones is conservative during pregnancy. Intervention will be necessary in patients who do not respond to conservative measures. Therefore, it is crucial to obtain a prompt and accurate diagnosis to optimize the management of these patients. Teaching Points • In pregnancy, renal colic is the most frequent nonobstetric cause for abdominal pain and hospitalization. • Magnetic resonance urography should be considered when ultrasound is nondiagnostic. • Low-dose CT should be considered as a last-line test during pregnancy.

Noninflammatory Conditions of the Small Bowel

Magnetic resonance (MR) imaging has been playing an evolving role in evaluating noninflammatory small-bowel conditions, such as tumors and malabsorption syndrome. MR imaging has shown to be superior to other diagnostic methods in identifying tumors of the small bowel. MR enterography and MR enteroclysis are both valid for studying noninflammatory conditions of the small intestine, although MR enteroclysis may be considered the modality of choice because of its accuracy in the diagnosis of small-bowel neoplasms. Intraluminal and extraluminal MR findings, combined with contrast-agent enhancement and functional information, help to make an accurate diagnosis and consequently to characterize small-bowel diseases.

Evaluating the Acute Abdomen in the Pregnant Patient

Acute abdominal pain in pregnancy presents diagnostic and therapeutic challenges. Ultrasound remains the primary imaging investigation of the pregnant abdomen because of its availability, portability, and lack of ionizing radiation. MR imaging has been shown to be useful in the diagnosis of gynecologic and obstetric problems and in the setting of acute abdomen during pregnancy. MR imaging is often used when ultrasound is inconclusive. Computed tomography is the investigation of choice when there is a life-threatening situation and in case of traumatic injuries, when a rapid diagnosis is required.

Are Second Trimester Apparent Diffusion Coefficient Values of the Short Uterine Cervix Associated with Impending Preterm Delivery

Purpose To prospectively determine whether the apparent diffusion coefficient (ADC) of the cervix is associated with preterm delivery in asymptomatic patients with a sonographic cervical length of 15 mm or less and positive fetal fibronectin test results between 23 and 28 weeks of gestation. Materials and Methods The institutional review board approved this prospective hypotheses-generating study. A total of 30 pregnant women (mean gestational age, 26 weeks) with a sonographic short cervix (≤15 mm) underwent pelvic 1.5-T magnetic resonance (MR) imaging. Oblique sagittal diffusion-weighted images were obtained with b values of 0, 400, and 800 sec/mm(2). ADC values at MR imaging of the subglandular and stromal cervix and the difference between both were correlated to the interval to delivery. Receiver operating characteristic curve analysis was performed to obtain sensitivity and specificity of ADC values in association with delivery within 7 days. Results Eight (27%) of 30 patients delivered within 6 or 7 days after MR imaging (impending delivery group), and 22 (73%) of 30 patients delivered between 18 and 89 days after imaging (mean, 55 days) (late delivery group). Mean subglandular ADC and mean ADC difference were higher (P < .001) in patients with impending delivery than in those with late delivery ([2406.3 ± 166.0] × 10(-6) mm(2)/sec vs [1708.9 ± 108.1] × 10(-6) mm(2)/sec and [657.3 ± 129.9] × 10(-6) mm(2)/sec vs [69.2 ± 70.2] × 10(-6) mm(2)/sec, respectively). Subglandular ADC inversely correlated with the interval between MR imaging and delivery (r = -0.75). Receiver operating characteristic curve analysis of subglandular ADC revealed 100% sensitivity (95% confidence interval: 63.1, 100) and 100% specificity (95% confidence interval: 84.6, 100) in association with impending delivery with a 1921 × 10(-6) mm(2)/sec threshold. Stromal ADC and sonographic cervical length showed no difference between groups (P = .072 and P = .511, respectively). Conclusion Cervical subglandular ADC at MR imaging is associated with impending preterm birth in patients with a short sonographic cervix. (©) RSNA, 2016.

To evaluate the feasibility of magnetic resonance imaging in predicting unusual site ectopic pregnancy: a retrospective cohort study

ObjectiveTo evaluate the accuracy of pelvic MRI in the diagnosis of unusual ectopic pregnancy (EP), when ultrasound (US) examination is inconclusive.MethodsWe retrospectively reviewed the medical records of 150 patients with suspected EP. Clinical, US and MRI features of 15 unusual EPs were analysed. Two radiologists independently reviewed each case resolving by consensus any diagnostic discrepancy. Interobserver agreement was assessed using the Cohen κ test.ResultsMRI displayed a gestational sac-like structure surrounded by a thick wall in all cases. The thick wall displayed hyperintensity in 41 %, isointensity in 35 % and hypointensity in 24 % of cases on T1-weighted images. Diffusion- and fat saturation T1-weighted images were the most accurate sequences, as they enabled identification of 15/15 and 14/15 patients, respectively. Although US was false negative in detecting cervical and uterine infiltration underlying the caesarean scar, MRI was able to identify the invasion. Interobserver agreement was very good for all sequences (κ=0.892–1.0).ConclusionsMRI plays an important role in the early diagnosis of unusual EP. It should be considered after negative US findings, providing accurate evaluation of the site and the possible infiltration of these lesions, which help in the management of these patients.Key Points• MRI is being increasingly used as a problem-solving modality in ectopic pregnancy.• MRI plays an important role in early diagnosis of unusual ectopic pregnancy.• Knowledge of MRI features in EP is essential to determinate appropriate management.

Magnetic Resonance Imaging and H-proton Spectroscopy assessment of maternal and foetal brains in a case of pregnancy-associated Wernicke encephalopathy

Gabriele Masselli, Maria Giulia Bernieri, Maria Grazia De Stefano, Anna Maria Maragno, Simona Patti, Paola Galoppi, Francesca Laghi, Vincenzo Cardinale, Gianfranco Gualdi and Roberto Brunelli Radiology Department, Umberto I Hospital, Sapienza University of Rome, Rome, Italy; Department of Obstetrics and Gynecology, Umberto I Hospital, Sapienza University of Rome, Rome, Italy; Department of Medico-Surgical Sciences and Biotechnologies, Umberto I Hospital, Polo Pontino, Sapienza University of Rome, Italy