An augmented patient-specific approach to administration of contrast agent for CT renal angiography.

PURPOSE: This hybrid retrospective and prospective study performed on 200 consecutive patients undergoing renal CTA, investigates the opacification of renal vasculature, radiation dose, and reader confidence. MATERIALS AND METHODS: 100 patients were assigned retrospectively to protocol A and the other 100 were allocated prospectively to protocol B. Both protocols implemented a contrast material and saline flow rate of 4.5 mL/sec. Protocol A utilized a 100 mL of low-osmolar nonionic IV contrast material (Ioversol 350 mg I/mL) while protocol B employed a patient-tailored contrast media formula using iso-osmolar non-ionic (Iodixanol 320 mg I/mL). RESULTS: Arterial opacification in the abdominal aorta and in the bilateral main proximal renal arteries demonstrated no statistical significance (p>0.05). Only the main distal renal artery of the left kidney in protocol B was statistically significant (p<0.046). In the venous circulation, the IVC demonstrated a significant reduction in opacification in protocol B (59.39 HU ± 19.39) compared to A (87.74 HU ± 34.06) (p<0.001). Mean CNR for protocol A (22.68 HU ± 13.72) was significantly higher than that of protocol B (14.75 HU ± 5.76 p<0.0001). Effective dose was significantly reduced in protocol B (2.46 ± 0.74 mSv) compared to A (3.07 ± 0.68 mSv) (p<0.001). Mean contrast media volume was reduced in protocol B (44.56 ± 14.32 mL) with lower iodine concentration. ROC analysis demonstrated significantly higher area under the ROC curve for protocol B (p<0.0001), with inter-reader agreement increasing from moderate to excellent in renal arterial visualization. CONCLUSION: Employing a patient-tailored contrast media injection protocol shows a significant refinement in the visualization of renal vasculature and reader confidence during renal CTA.

Augmented Quadruple-Phase Contrast Media Administration and Triphasic Scan Protocol Increases Image Quality at Reduced Radiation Dose During Computed Tomography Urography.

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.

New trends in the management of hepatic Echinococcus granulosus.

The liver is the most commonly involved organ in the body by cystic echinococcosis (CE) secondary to infection with Echinococcus granulosus. In this article, the authors discuss the classification, recent advances in magnetic resonance (MR) imaging for the diagnosis of hepatic CE, and approaches for management of hepatic CE using five therapeutic options that include: antihelminthic chemotherapy, surgery, percutaneous treatment, endoscopic approach, and the "watch and wait" approach.

Clinical review of liver hydatid disease and its unusual presentations in developing countries.

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.

Radiology of terror injuries: the American University of Beirut Medical Center experience.

OBJECTIVE: This study aimed to report our experience with regard to imaging of mass casualty incidents (MCIs). SUBJECTS AND METHODS: Following a bomb attack, 150 casualties were referred to our hospital. Radiographs and nonenhanced CT scans were performed in 28 individuals. RESULTS: Major injuries were seen in 12 individuals, which were limited only to the brain (n=2), facial bones (n=2), and extremities and soft tissues (n=8). CONCLUSION: In MCIs, imaging should be fast, in order to help identify major injuries that need immediate management and to help in the triage of injured individuals.

Life-threatening liver laceration with arterial hemorrhage complicating percutaneous treatment of hepatic hydatid cyst.

We present a 76-year-old woman known to have a large right hepatic lobe hydatid cyst which recurred twice after surgical excision. CT-guided percutaneous alcohol ablation was conducted to sclerose the cyst, but the procedure was complicated by parenchymal liver laceration and active arterial hemorrhage from a branch of the right hepatic artery. Bleeding was controlled by both endovascular and surgical interventions. Liver laceration with arterial hemorrhage is a rare not previously reported serious complication of percutaneous treatment of hepatic hydatid cyst that may be potentially life-threatening.

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.

Alternative diagnoses of acute appendicitis on helical CT with intravenous and rectal contrast.

At our institution, helical CT of the abdomen and pelvis with intravenous and rectal contrast (CTRC) has become the modality of choice for investigation of patients with right lower quadrant pain and clinical suspicion of acute appendicitis. CTRC has proven useful for the diagnosis of acute appendicitis (AA) and at the same time identifies alternative diagnoses mimicking AA. This pictorial assay illustrates the imaging findings of AA and its mimickers including primary epiploic appendagitis, right-sided diverticulitis, torsion of Meckel's diverticulum, gynecologic disorders, obstructive uropathy, right lower lobe pneumonia, and other conditions.

Imaging findings of familial Mediterranean fever.

PURPOSE: The aim of this study was to study the imaging findings of familial Mediterranean fever (FMF). MATERIALS AND METHODS: We performed a retrospective review of the medical records and imaging studies of 38 patients with proven FMF, diagnosed between 1992 and 2002. RESULTS: The most common clinical manifestation was recurrent peritoneal attacks with abdominal pain (76.3%) and fever (42.1%). Abdominal imaging findings included ileus (n=12), splenomegaly (n=5), hepatomegaly (n=2), ascitis (n=2), focal peritonitis (n=2), mesenteric streaking (n=1), and enlarged mesenteric lymph node (n=1). One patient developed fatal peritoneal mesothelioma, and 13.1% of the patients developed amyloidosis with sonographic findings of renal parenchymal disease or cardiomyopathy. Arthritis was second in frequency, occurring in 34.2% of patients; radiographs were normal (n=4) or showed joint effusion and periarticular soft tissue swelling (n=4) due to synovitis. One patient developed seronegative destructive arthropathy. Skin lesions were noted in 23.6% of patients. Pleuritis was encountered in 13.1% and pericarditis in 5.2%. Polyarteritis nodosa (PAN) was present in two patients, multiple sclerosis in one, and autoimmune hemolytic anemia in one patient. CONCLUSION: FMF predominantly involves abdominal viscera but can affect other organs. The majority of patients have nonspecific imaging findings, and the radiologic diagnosis is rarely considered. Amyloidosis, mesothelioma, and destructive arthropathy are potential serious complications of FMF. PAN, multiple sclerosis, and autoimmune hemolytic anemia are probably rare associations or rather than coincident with FMF.

Imaging of back pain in children and adolescents.

PURPOSE: To present the imaging findings of the wide spectrum of musculoskeletal diseases causing back pain in children and adolescents. DISCUSSION: Back pain in children is a rare condition but may denote a serious health problem; hence, full clinical history, physical examination, and appropriate laboratory studies should be obtained. In this scientific exhibit, we present the imaging findings of the variable musculoskeletal diseases that are associated with back pain in children and adolescents. These disease processes include scoliosis of various causes; spondylolysis; spondylolisthesis; traumatic injuries; disc degeneration and herniation; Scheuermann's disease; spondylodiscitis; tumors (primary, secondary, hematogenous); and miscellaneous conditions (eg, metabolic disorders, sickle cell disease, osteoporosis). CONCLUSION: A wide spectrum of diseases causing back pain in children is presented. Radiologists should be aware of the imaging findings of this rather uncommon entity to help in reaching the appropriate diagnosis.

Image-guided ureteral reconstruction using rendezvous technique for complex ureteric transection after gunshot injuries.

Management of complex ureteric transection poses a significant clinical challenge, particularly after gunshot injuries due to marked distortion of anatomy and associated tissue loss. We report two cases of total ureteric transection due to gunshot injury successfully repaired using fluoroscopy-guided rendezvous procedure and double J stent placement. This minimally invasive approach may offer a safe and effective technique to repair complete ureteral transection and obviate the need for complex surgical procedures.

The value of contrast-enhanced helical CT scan with rectal contrast enema in the diagnosis of acute appendicitis.

BACKGROUND: The aim of this retrospective study is to assess the accuracy of single slice helical CT scan with intravenous, and rectal contrast (CTRC) in the diagnosis of acute appendicitis (AA) in patients with suspected AA, with particular analysis of the diagnostic signs. PARTICIPANTS AND METHODS: Abdomino-pelvic helical CTRC was performed on 75 consecutive patients with suspicion of AA. Radiologic diagnosis was compared with surgical/pathologic results and clinical follow-up. In addition, the CTRC examinations were retrospectively reviewed independently by two experienced radiologists using predefined diagnostic criteria. The sensitivity, specificity, and frequency of each diagnostic sign were calculated. The interobserver agreement and the statistical significance of the frequency for each diagnostic criterion were assessed using the Kappa and Fisher tests, respectively. RESULTS: The accuracy of helical CTRC in the diagnosis of AA was 94.7%, sensitivity 100%, specificity 90%, PPV 89.7%, and the NPV 100%. Wall enhancement and nonopacification of the appendix recorded the highest sensitivity and specificity (97% and 100%, 94% and 95%, respectively). Appendiceal thickness greater than 6 mm was present in 100% of true-positive cases. However, 26.5% of true-negative cases had also an appendiceal diameter exceeding 6 mm, a value used as a cut-off for normal appendiceal diameter. The highest interobserver agreement was recorded for appendiceal wall enhancement and for nonopacification of the appendix (K=0.97 and 0.88, respectively). CONCLUSIONS: CTRC is an accurate and relatively fast technique for investigation of patients with suspected AA. A negative CTRC can exclude completely the diagnosis of AA. Nonopacification of the appendix and appendiceal wall enhancement are highly sensitive, specific, and reproducible, signs representing major criteria for the diagnosis of AA.

Current imaging of solid renal masses.

More than 40% of solid renal masses are incidentally discovered by ultrasound examinations. Computed tomography (CT) remains the cornerstone investigation for characterization and assessment of the extent of renal tumors, it is complementary to ultrasound. MR imaging is an adjunctive method reserved as a problem-solving technique for indeterminate masses by ultrasound and CT. PET-CT has a great potential role in the staging of renal cancer.

Incidence of urinary tract infection following transrectal ultrasound guided prostate biopsy at a tertiary-care medical center in Lebanon.

OBJECTIVE: To determine the incidence of urinary tract infections (UTIs) following transrectal ultrasound guided needle biopsy of the prostate (TRUBP) and the bacteriology of these infections. DESIGN: Retrospective evaluation of the charts and records of all patients who underwent TRUBP between June 1, 2002, and August 31, 2003. SETTING: American University of Beirut Medical Center, a tertiary-care center in Lebanon. PATIENTS: Two hundred seven patients underwent TRUBP. All received prophylactic antibiotics. One hundred twenty (58%) received ciprofloxacin alone, whereas 87 (42%) received both ciprofloxacin and gentamicin. Sixty-one patients (29.5%) had an enema prior to the procedure, whereas 146 (70.5%) did not. RESULTS: Thirteen patients (6.3%) were admitted with UTI. All had rigors and fever on admission. Symptoms appeared at a mean of 2.7 days and the mean hospital stay was 9.2 days. The mean duration of antibiotic treatment was 23.2 days. Ten (77%) of the patients had positive bacteriology. Urine cultures were positive in 8 (61.5%) of the patients and blood cultures in 6 (46.2%). All positive cultures grew Escherichia coli resistant to ciprofloxacin, with 5 isolates producing extended-spectrum betalactamases. CONCLUSIONS: TRUBP continues to be associated with significant infectious complications, especially UTI. Given the increasing incidence of antibiotic resistance mainly among the Enterobacteriaceae, antimicrobial prophylaxis practices should be reevaluated and the universal administration of quinolones alone or in combination with aminoglycosides should be reconsidered.

Diagnosis and treatment of midline prostatic cysts.

We report three patients with midline prostatic cysts (simple, n=1; complex, n=2) that presented with low ejaculate volume and hematospermia. Transrectal ultrasound (TRUS) revealed a midline prostatic cystic structure that could represent either an ejaculatory duct cyst or a Müllerian duct cyst. In one patient, the ejaculatory duct cyst was confirmed by identification of spermatozoa at microscopic analysis of fluid obtained by TRUS-guided needle aspiration. The two other patients underwent transurethral incision of the cyst with complete resolution of symptoms.

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.

Periprostatic infiltration with local anesthesia during transrectal ultrasound-guided prostate biopsy is safe, simple, and effective: a pilot study.

OBJECTIVE: Transrectal ultrasound (TRUS)-guided prostate needle biopsy is the standard procedure to diagnose prostate cancer. It can be associated with significant discomfort and pain. We evaluated if periprostatic infiltration with local anesthetic reduces this discomfort. MATERIAL AND METHODS: 72 patients underwent TRUS-guided prostate needle biopsy. All patients had 12 cores, with four prostatic zones of biopsies. In 25 consecutive patients (G1) with a median prostate size of 47 cc, no anesthesia was given; while in 47 sequential patients (G2) with a median prostate size of 50 cc, 2 ml of 2% lidocaine was infiltrated in the periprostatic area around the neurovascular bundle using 20-cm-long, 22-gauge needle on both sides as guided by color Doppler. Biopsies were performed in standard fashion. Discomfort was graded on a scale from 0 to 10 with 0 meaning no discomfort, 1-3 mild, 4-6 moderate, and 7-10 severe. RESULTS: 12/25 (48%) of G1 patients reported no discomfort compared to 70% in G2 (P=.025). Mild discomfort was reported in 5/25 (20%) patients of G1 and 9/47 (19%) patients of G2. Moderate or severe discomfort was reported in 8/25 (32%) patients and 5/47 (11%) patients in G2 (P=.039). Prostate size did not affect degree of discomfort within each group and between both subgroups. No adverse reactions were observed secondary to lidocaine infiltration. CONCLUSION: Periprostatic infiltration with local anesthesia at the time of TRUS-guided prostate needle biopsy significantly reduces discomfort. It is easy to perform, safe, and should be considered in all patients irrespective of the prostate size.