Fadi El-Merhi

A 58-year-old male patient, previously healthy, presented with right flank pain of few hours duration. Initial workup showed an elevated creatinine and right hydroureteronephrosis. Computed tomography imaging revealed a retroperitoneal soft tissue mass encasing the right common iliac artery which is a first reported case in its anatomical distribution. Patient was referred to interventional radiology service where a percutaneous nephrostomy tube was placed followed by double J stenting. Subsequently, treatment with steroids was started. Follow up imaging a few months later revealed progressive resolution of the inflammatory process.

Key words: Computed Tomography Angiography; Kidney; Radiation Dosage

Aim: To investigate the frequency of different etiologies of acute scrotal pain in males presenting to the emergency department at American University of Beirut Medical Center in Beirut, Lebanon. Materials and Methods: In all, 94 patients between the ages 18 and 40 years presenting to the emergency room at American University of Beirut Medical Center with acute scrotum were recruited. The scrotum was inspected with palpation, and Doppler Ultrasound of the testicle was performed by a radiology resident to confirm the diagnosis. The study results were then collected after the official reports were signed by a board-certified radiology attending with expertise in ultrasound. Results: Of the 94 patients presenting with acute scrotal pain, 23.4% (95% confidence interval (0.70–0.87)) had no ultrasound findings and were considered normal. On the other hand, 54.3% (95% confidence interval (0.45–0.66)) were diagnosed with varicocele, 9.6% (95% confidence interval (0.04–0.16)) were diagnosed with epididymo-orchitis, and 9.6% (95% confidence interval (0.04–0.16)) had a history of trauma to the testicle. Patients presenting with acute scrotum had a pain duration of 13.2 ± 4.5 h, with 10.6% (95% confidence interval (0.04–0.17)) having associated urinary symptoms, 18.1% (95% confidence interval (0.09–0.25)) have had sexual activity within 48 h of presentation, and 10.6% (95% confidence interval (0.04–0.17)) were pre-diagnosed with varicocele. Conclusion: Varicocele is the most common cause of acute scrotal pain in patients presenting to American University of Beirut Medical Center in Beirut. This should direct varicocele to the top of our differential when a patient with acute scrotum presents to the emergency department. Nevertheless, ruling out torsion remains the first step in the workup.

SUMMARY: The pathogenesis of multiple sclerosis is characterized by a cascade of pathobiologic events, ranging from focal lymphocytic infiltration and microglia activation to demyelination and axonal degeneration. MS has several of the hallmarks of an inflammatory autoimmune disorder, including breakdown of the BBB. Gadolinium-enhanced MR imaging is currently the reference standard to detect active inflammatory lesions in MS. Knowledge of the patterns and mechanisms of contrast enhancement is vital to limit the radiologic differential diagnosis in the staging and evaluation of MS lesion activity. The aim of this review was the following: 1) to outline the pathophysiology of the effect of lymphocyte-driven inflammation in MS, 2) to describe the effects of gadolinium on the BBB and glymphatic system, and 3) to describe gadolinium enhancement patterns and artifacts that can mimic lesions in MS.

Human hydatid cyst disease is an international public health issue that particularly affects the developing countries. In this article, we discuss the epidemiology of hydatid disease in third world countries, the life cycle of echinococcus granulosus and how to make the clinical diagnosis of the disease, including laboratory tests and imaging modalities as well as uncommon presentation of this entity that we have encountered at the American University of Beirut Medical Center (AUBMC). We emphasize on the new World Health Organization classification of hepatic echinococcosis with examples from our clinical practice at AUBMC, and finally we describe the treatment, including medical and interventional therapies.

Purpose The aim of this article was to investigate the opacification of the renal vasculature and the urogenital system during computed tomography urography by using a quadruple-phase contrast media in a triphasic scan protocol. Materials and Methods A total of 200 patients with possible urinary tract abnormalities were equally divided between 2 protocols. Protocol A used the conventional single bolus and quadruple-phase scan protocol (pre, arterial, venous, and delayed), retrospectively. Protocol B included a quadruple-phase contrast media injection with a triphasic scan protocol (pre, arterial and combined venous, and delayed), prospectively. Each protocol used 100 mL contrast and saline at a flow rate of 4.5 mL. Attenuation profiles and contrast-to-noise ratio of the renal arteries, veins, and urogenital tract were measured. Effective radiation dose calculation, data analysis by independent sample t test, receiver operating characteristic, and visual grading characteristic analyses were performed. Results In arterial circulation, only the inferior interlobular arteries in both protocols showed a statistical significance (P < 0.05). Venously, the inferior vena cava, proximal and distal renal veins demonstrated a significant opacification reduction in protocol B than in protocol A (P < 0.001). Protocol B showed a significantly higher mean contrast-to-noise ratio than protocol A (protocol B: 22.68 ± 13.72; protocol A: 14.75 ± 5.76; P < 0.001). Radiation dose was significantly reduced in protocol B (7.38 ± 2.22 mSv) than in protocol A (12.28 ± 2.72 mSv) (P < 0.001). Visual grading characteristic (P < 0.027) and receiver operating characteristic (P < 0.0001) analyses demonstrated a significant preference for protocol B. Conclusions In computed tomography urography, augmented quadruple-phase contrast media and triphasic scan protocol usage increases the image quality at a reduced radiation dose.

Renal pseudoaneurysm (PSA) is a rare complication post kidney transplant biopsy that accounts for less than 1% of allograft dysfunction. Imaging guidelines in the diagnosis of renal PSA have not yet been developed owing to the low occurrence and limited data availability. However, contrast-enhanced CT and magnetic resonance angiography (MRA) are the preferred modalities in detecting PSA owing to the high contrast and spatial resolution. However, magnetic resonance angiography is preferred since non-contrast imaging techniques can see blood flow patterns in renal PSA without the use of contrast media that may alter renal function. We present a rare complication in a 48-year-old male receiving a living related kidney transplant and found to have renal PSA post allograft biopsy. We review the clinical features, imaging and treatment outcome with the developed PSA in the transplanted kidney post allograft biopsy.