Iranian Journal of Radiology
Year:2007 | Volume:4 | Issue:4|Papers Count:11

Multidetector computed tomography (MDCT) with or without ECG-synchronized images can successfully evaluate cardiac morphology and congenital heart diseases which mainly involve great vessels. In this pictorial essay, we present the great capability of MDCT for the evaluation of complex congenital heart disease.

Background/Objective: Awareness of invasion to the walls of the carotid arteries by malignant tumors, either tumoral mass or metastatic lymph nodes, is of great clinical importance before surgery and can change the management strategy. This study was conducted to assess the diagnostic value of computed tomography (CT) in determining invasion to carotid artery (CA) by oromaxillofacial and neck malignant tumors.Patients and Methods: CT with contrast was performed in 40 patients who has had oromaxillofacial and neck malignant tumors before surgical intervention. Abnormal CT findings in our patients were categorized into 6 types: I) tumor encasement of carotid arteries ≥270 degrees; II) tumor encasement of carotid arteries ≥180 degrees; III) compression and deformation of CA; IV) displacement of CA; V) ill-defined CA wall; and VI) the segmental deletion of fat or fascial planes between tumor and CA. The CT appearances of all tumors were prospectively compared with surgical findings.Results: Abnormal CT findings in our patients included 6 with form I; 17 with type II; 2 with type III; 8 with type IV; 7 with type V; and 33 with type VI. Surgical findings showed that the tumors invaded CA vessels in 13 of 40 patients. The sensitivity, specificity, accuracy and positive and negative likelihood ratio values with 95% confidence interval for type I were 0.31, 0.93, 0.7, 4.15 and 1.3; for type II were 0.62, 0.67, 0.65, 1.8 and 1.7; for type III were 0, 0.93, 0. 63, 0 and 0.93; for type IV were 0.07, 0.74, 0.53, 0.3 and 0.8; for type V were 0.39, 0. 93, 0.69, 5.2 and 1.6; and for type VI were 1, 0.26, 0.50 and 1.35, respectively.Conclusion: Though many CT findings are of value in determining of CA invasion by head and neck tumors, our study demonstrated that encasement ≥270 degree (type I), ill-defined wall of the artery (type V) and segmental deletion of fat or fascial planes between tumor and CA (type VI) are valuable in determining CA invasion by tumors. However, CT is not a definite way for the diagnosis of CA involvement by malignant tumoral lesions.

Primary hydatidosis of muscle is very rare and can cause a variety of diagnostic problems. Its diagnosis is based on clinical, laboratory and radiological findings. As this infestation resembles a soft tissue tumor on clinical examination, the preoperative radiological diagnosis is very important to avoid unnecessary biopsy. The objective of this article is to present the pathognomonic “Water-lily sign” that has not been previously reported in this muscle group.To the best of our knowledge, our case is the second reported case of this pathognomonic sign in magnetic resonance imaging of primary intramuscular hydatidosis.

Background/Objective: To determine the frequency of computed tomography (CT) findings in patients with mild head trauma.Patients and Methods: In this cross-sectional study conducted between September 2005 and April 2006, 708 patients with mild head trauma as defined by a Glasgow Coma Score (GCS) of 13–15, were underwent standard clinical examination and cranial CT.Results: The mean±SD age of our patients was 26.8±19.03 years (range: 1 month to 89 years). 489 (68.9%) patients were male and 219 (30.8%) were female. GSC was 13 in 1%, 14 in 4.6% and 15 in 94.4% of patients. The most common mechanism of trauma was car accident and falling down, each of which happened for 132 patients (18.6%).The most common findings on CT were subgaleal hematomas in 213(30%) and intracranial lesions were seen in 41 patients (5.8%); among them 37 were male. Among intracranial lesions, the most common finding was epidural hematoma in 18 patients followed by hemorrhagic contusion in 13 patients. Intracranial lesions were observed in 28.6% of patients with GCS of 13; in 15.2% with GCS of 14 and in 5.1% with GCS of 15 (P=0.002).Conclusion: Many of patients with GCS equal to 15 after head trauma have considerable intracranial lesions and minor focal neurologic signs revealed by careful physical examination could be a good marker of these lesions.

During the last two decades, magnetic resonance imaging has been widely used in the diagnosis and treatment monitoring of multiple sclerosis. MRI, both conventional and non conventional methods, has transformed all aspects of MS research and clinical practice in recent years. Although advanced imaging methods have added much more to our knowledge about pathogenesis and natural history of the disease but their cost, availability, complexity and lack of validation have limited their use in routine clinical practice. Conventional MR techniques including proton density, T1/T2-Weighted images and fluid- attenuated inversion recovery sequences are now accepted in standard protocols for diagnosis and treatment outcome measures in clinical trials of multiple sclerosis. This review will focus on the type, morphology and evolution of MS lesions regarding conventional MRI and their use for treatment monitoring in daily clinical practice.

Intracranial aneurysms in neonatal period and early infancy may be resorbed spontaneously or due to removal of predisposing factors. Herein, we presented a rare case of vanishing of a large thrombosed intracranial aneurysm in a 25-day-old girl presented with head enlargement and vomiting. Magnetic resonance imaging (MRI) revealed a severe hydrocephalus accompanied by a 1.5-cm aneurysm at the bifurcation of the right middle cerebral artery (MCA).  Doppler ultrasonography confirmed a flow with a magnitude almost similar to that of the right MCA flow, inside the mass located adjacent to it.  The hydrocephalus was managed by ventriculo-peritoneal (VP) shunt. The patient underwent a conservative observation for several months. Subsequently, the aneurysm was vanished in control images.

Background/Objective: Ultrasound (US) detection of prenatal central nervous system (CNS) anatomic anomalies is very important in making decision about therapeutic termination. In the present study, the accuracy of US in detection of gross prenatal CNS anatomic anomalies has been investigated. Patients and Methods: 3012 pregnant women were scanned after 18 weeks of gestation by an expert operator in a referring center. All delivered fetuses were followed after birth through clinical examination and sonography. Results: In this study, the accuracy of US in detection of gross CNS anatomic anomalies of fetuses after 18 weeks gestation was found to be 100%. The sensitivity, specificity, positive and negative predictive values of US were 100%. In sonographic examination of these 3012 pregnant women, 36 fetuses were detected with CNS anomalies, some of whom had more than one anomaly. Gross CNS anomalies observed included microcephaly, hydrocephaly, anencephaly, holoprosencephaly, ventriculomegaly, meningocele, encephalocele, lissencephaly, agenesis of corpus callosum, bilateral choroid plexus cysts and hypoplastic cerebellum. Conclusion: US is highly operator dependent and operator experience may be the most determinant affecting the results. Sonographic scanning after 18 weeks of gestation is associated with the best results.

The incidence of anomalies is high in multiple gestations especially in monochorionic twins. This paper reported a case of an acardiac parabiotic twin, a rare deformed fetus which occurs typically in monochorionic twin gestations. It is a severely deformed fetus without heart and limited development of the upper half of the body.

Backgrounds/Objective: In patients with atypical hemangiomas who have inconclusive imaging features, performing other diagnostic procedures, especially biopsy, is indicated. Bleeding is the most feared complication due to the high vascular nature of hemangioma. The objective of this study was to present our experience on ultrasound-guided core needle biopsy of liver hemangiomas. Patients and Methods: We carried out ultrasound-guided core needle biopsies in 443 patients with focal hepatic lesions of whom 32 were subsequently diagnosed as having cavernous hemangiomas. Biopsies were done using a 16–18 G cutting needle at Mashhad Imam Reza Hospital and Isfahan Baharestan Hospital during 2004–07. Results: The mean age of patients with hemangioma was 49.3 years (F/M = 2/1). The lesions were 0.8–14 (mean: 6.5) cm long. 13 patients had multiple (2–10) lesions; others had solitary lesions with atypical imaging features. We did not observe any complications including hemorrhage during or after the procedure. Conclusion: Ultrasonically-guided core needle biopsy seems to be a relatively safe procedure even when "atypical hemangioma" is a diagnostic possibility.

An eight-year-old child presented with history of frequent episodes of complex partial seizures and homonymous hemianopsia for the past six months. She also had history of headache and occasional vomiting for the same period. The child had suffered from tuberculous meningitis almost 12 months before for which a complete course of treatment was administerted. Physical examination of the child was non-revealing with no signs of meningeal irritation. However, papilloedema was observed on fundoscopy. Hemogram and erythrocyte sedimentation rate (ESR) were within normal limits. Brain computed tomography (CT) was done and both axial and coronal scans were taken (Figs. 1 and 2)

Figures 1 and 2: Brain CT shows disproportionate enlargement of temporal horn and atrium of the right lateral ventricle with periventricular hypodensity and relatively normal sized contralateral ventricle as well as frontal horn of the ipsilateral ventricle.The term "entrapment of temporal horn" was first used by Maurice Williams, et al, to describe focal ventricular dilatation of the temporal horn caused by occlusion of the cerebrospinal fluid (CSF) pathway at the atrium of the lateral ventricle....