Lena Naffaa

CT findings of omental torsion and infarction Case report and review of the literature

A 37-year-old woman presented with progressive diffuse abdominal pain. Computed tomography (CT) showed diffuse streaking of the greater omentum with a mass of fat density located anteriorly just below the umbilicus, showing a whirling pattern of concentric streaks. Surgery and pathology revealed torsion and infarction of the greater omentum. Because of its rarity and nonspecific clinical features, the diagnosis is seldom made preoperatively. We describe a patient with characteristic CT findings of omental torsion. Preoperative diagnosis is important since conservative management has been suggested.

Juvenile ossifying fibroma: CT and MR findings

Abstract. We describe the CT findings in four patients and the MR imaging in one patient with juvenile ossifying fibroma. Three lesions involved the maxillary sinus and extended to the surrounding structures; one lesion was confined to the maxillary bone. CT scan revealed well-defined, expansile lesions with variable amount of calcifications. On MRI one lesion had intermediate signal intensity with significant contrast enhancement.

Imaging of Acute Pelvic Pain in Girls: Ovarian Torsion and Beyond☆

Identifying the etiology of acute pelvic pain in girls is often clinically challenging. Particularly in young girls, it is often difficult to determine if acute pelvic symptoms are originating from a gynecologic source or from a genitourinary or gastrointestinal etiology based on the childs clinical examination alone. Therefore, imaging plays a key role in establishing a diagnosis and in directing medical and surgical treatment. Pediatric gynecologic conditions, which can present acutely with pain or mass or both include ovarian torsion, hematometrocolpos, pelvic inflammatory disease, inguinal hernias containing an ovary or the uterus or both, adnexal cysts, pregnancy, vaginal foreign bodies, and ovarian vein thrombosis. Sources of pelvic pain in girls from nongynecologic etiologies include appendicitis, distal ureterolithiasis, and Crohns disease. Owing to the lack of ionizing radiation, widespread availability, and lack of need for sedation, gray scale, with color Doppler ultrasound examination is often the initial imaging obtained when there is suspicion of gynecologic pathology. Radiographs of the abdomen and pelvis are commonly used in the acute setting, when there is concern for a bowel obstruction or free intraperitoneal air. Cross-sectional imaging with computed tomography or magnetic resonance imaging is used, when the diagnosis remains unknown and to clarify findings found on ultrasound and radiographs. Correctly identifying and diagnosing the causes of acute pelvic pain in girls is crucial for the care of these patients. Here, we review the spectrum of causes of acute pelvic pain in female infants to teens with emphasis on imaging approach and age-related characteristics. OBJECTIVES

Transcranial Doppler screening in sickle cell disease: The implications of using peak systolic criteria.

AIM To compare time average maximum mean velocity (TAMV) and peak systolic velocity (PSV) criteria of Trans Cranial Doppler (TCD) in their ability to predict abnormalities on magnetic resonance imaging (MRI)/magnetic resonance angiogram (MRA) in patients with sickle cell disease. METHODS A retrospective evaluation was performed of the outcomes in all patients with a Transcranial Doppler examination at our institution since the implementation of the hospital picture archiving and communication system (PACS) system in January 2003 through December 2012. All ultrasound imaging exams were performed by the same technologist with a 3 MHz transducer. Inclusion criteria was based upon the Transcranial Doppler procedure code in our PACS which had an indication of sickle cell disease in the history. The patients age and gender along with the vessel with the highest time averaged mean velocity as well as the highest peak systolic velocity was recorded for analysis. A subset of the study cohort also had subsequent MR imaging and Angiograms performed within 6 mo of the TCD examination. MRI results were categorized as having a disease related abnormality (vessel narrowing, collateral formation/moya-moya, or abnormal fluid attenuation inversion recovery signal in parenchyma indicative of prior stroke) or normal. The MRI results formed the comparison standards for TCD exams in evaluating intracranial injury. Sensitivity and specificity for the two TCD criteria (TAMV and PSV) were calculated to determine which could be a better predictor for intracranial vasculopathy /clinically occult strokes. RESULTS The study cohort for our institution was 110 patients with a total of 291 TCD examinations. These patients had a mean age of 7.6 years with a range from 2-18 years of age. Sixty-two of the 110 patients (56%) had two or more TCD exams. Thirty-seven patients (34%) had at least one MRI following a TCD examination. Of the 291 TCD examinations, 46 (16%) were conditional or abnormal by TAMV criteria. One hundred and sixteen (40%) were conditional or abnormal by PSV criteria. All studies that were abnormal by TAMV were also abnormal by PSV criteria. Seventy of the 116 (60%) studies which were conditional or abnormal by peak systolic criteria would not have been identified by time averaged mean maximum velocity criteria. The most frequent location of highest velocity measurement was noted to be in the middle cerebral artery regardless of whether it was measured by PSV or TAMV. From the 37 patients having one or more MRIs, 43 MRI exams were performed within 6 mo of a TCD examination. Twenty two (51%) MRIs had a disease related abnormality reported. When evaluating conditional or abnormal exams by PSV criteria against follow-up MRI/MRA, the sensitivity was 73% [16/(16 + 6)] and specificity was 81% [17/(4 + 17)]. When evaluating conditional or abnormal exams by TAMV criteria by follow-up MRI/MRA as the gold standard, the sensitivity was 41% [9/(9 + 13)] and the specificity was 100% [21/(21 + 0)]. In using conditional or abnormal criteria from PSV and TAMV to predict abnormalities on follow-up MRI/MR Angiogram, PSV was more sensitive (73% vs 41%) while TAMV was more specific (100% vs 81%). CONCLUSION Based on the data obtained at our institution and using the assumption that the best screening test is the one with the highest sensitivity, the peak systolic velocity could be the measurement of choice for TCD screening.

256 Slice Multi-detector Computed Tomography Thoracic Aorta Computed Tomography Angiography: Improved Luminal Opacification Using a Patient-Specific Contrast Protocol and Caudocranial Scan Acquisition.

Clinical Relevance Statement Caudocranial scan direction and contrast injection timing based on measured patient vessel dynamics can significantly improve arterial and aneurysmal opacification and reduce both contrast and radiation dose in the assessment of thoracic aortic aneurysms (TAA) using helical thoracic computed tomography angiography (CTA). Objectives To investigate opacification of the thoracic aorta and TAA using a caudocranial scan direction and a patient-specific contrast protocol. Materials and Methods Thoracic aortic CTA was performed in 160 consecutive patients with suspected TAA using a 256-slice computed tomography scanner and a dual barrel contrast injector. Patients were subjected in equal numbers to one of two contrast protocols. Patient age and sex were equally distributed across both groups. Protocol A, the departments standard protocol, consisted of a craniocaudal scan direction with 100 mL of contrast, intravenously injected at a flow rate of 4.5 mL/s. Protocol B involved a caudocranial scan direction and a novel contrast formula based on patient cardiovascular dynamics, followed by 100 mL of saline at 4.5 mL/s. Each scan acquisition comprised of 120 kVp, 200 mA with modulation, temporal resolution 0.27 seconds, and pitch 0.889:1. The dose length product was measured between each protocol and data generated were compared using Mann-Whitney U nonparametric statistics. Receiver operating characteristic analysis, visual grading characteristic (VGC), and &kgr; analyses were performed. Results Mean opacification in the thoracic aorta and aneurysm measured was 24 % and 55%, respectively. The mean contrast volume was significantly lower in protocol B (73 ± 10 mL) compared with A (100 ± 1 mL) (P<0.001). The contrast-to-noise ratio demonstrated significant differences between the protocols (protocol A, 18.2 ± 12.9; protocol B, 29.7 ± 0.61; P < 0.003). Mean effective dose in protocol B (2.6 ± 0.4 mSv) was reduced by 19% compared with A (3.2 ± 0.8 mSv) (P < 0.004). Aneurysmal detectability demonstrated significant increases by receiver operating characteristic and visual grading characteristic analysis for protocol B compared with A (P < 0.02), and reader agreement increased from poor to excellent. Conclusions Significant increase in the visualization of TAAs following a caudocranial scan direction during helical thoracic CTA can be achieved using low-contrast volume based on patient-specific contrast formula.

Semimembranosus muscle herniation: a rare case with emphasis on muscle biomechanics

Muscle herniations are rare and most reported cases involve muscles of the lower leg. We use a case of muscle herniation involving the semimembranosus muscle, presenting as a painful mass in an adolescent male after an unspecified American football injury, to highlight a simple concept of muscle biomechanics as it pertains to muscle hernia(s): decreased traction upon muscle fibers can increase conspicuity of muscle herniation(s)—this allows a better understanding of the apt provocative maneuvers to employ, during dynamic ultrasound or magnetic resonance imaging, in order to maximize diagnostic yield and, thereby, limit patient morbidity related to any muscle herniation. Our patient subsequently underwent successful decompressive fasciotomy and has since returned to his normal daily activities.

Routine surveillance imaging after end of therapy for pediatric extracranial tumors: A retrospective analysis

Frequent surveillance imaging is routine practice for pediatric patients after cancer therapy. This retrospective study evaluated the follow‐up of 301 children with extracranial tumors diagnosed between 2002 and 2012, at a tertiary pediatric cancer center in Beirut, Lebanon. Recurrence occurred in 15% of patients, at a median of 12 months after end of primary therapy. Outcome was not different comparing patients with recurrence detected via imaging surveillance versus clinically. False positive findings in 55 patients led to further interventions. These results raise important questions regarding benefit of current surveillance practices as standard care, especially in countries with limited resources.

Isolated Avulsion Fracture of the Medial Head of the Gastrocnemius Muscle in a Young Boy

An isolated avulsion fracture of the medial head of the gastrocnemius muscle without associated ligamentous or tendinous injury is a rare injury.To our knowledge there are only two reports of such cases in the English medical literature. We report an avulsion fracture of the medial femoral condyle at the insertion of the medial head of gastrocnemius muscle in a 13year-old boy following a skiing injury, the youngest patient with this injury reported to date. Our goal is to review the literature focusing on the role of magnetic resonance imaging (MRI) in the diagnostic approach of such injuries often very difficult to recognize by simple radiographs.

Isolated delayed metastasis to the talus from Ewing's sarcoma

Bone metastasis to the hands and feet, known as acrometastasis, is a very rare finding and tends to be associated with extensive metastasis. We herein report the case of a 14-year-old girl known to have a history of successfully treated Ewings sarcoma arising from the ribs, who presented with a pathologically proven isolated metastatic lesion to the talus 7 years after achieving clinical and radiologic remission. We describe the imaging findings on MRI, CT scan and PET-CT. To our knowledge, talar metastasis from Ewings sarcoma has been previously reported only twice in the English literature. Noteworthy is the fact that one of the previously reported lesions was considered a skip metastasis, and the other was under-described in terms of primary and secondary tumor location and time to metastasis. In addition, the overall imaging findings were rather suggestive of a benign lesion, particularly on CT scan.

The short esophagus: Review of a neglected entity

In this pictorial essay, the authors discuss etiologies, imaging findings with focus on fluoroscopy and management of the short esophagus in children and adults.