Findings Of Imaging Studies Research Articles

Somatosensory Auras in Refractory Temporal Lobe Epilepsy

To determine the prevalence, manifestations, lateralizing value, and surgical prognostic value of somatosensory auras (SSAs) in patients with refractory temporal lobe epilepsy (TLE). Eighty-one consecutive patients undergoing temporal lobectomy for refractory complex-partial seizures were screened for SSAs. The characteristics of the somatosensory phenomena, occurrence of other aura types, seizure semiology, findings of EEG and imaging studies, temporal lobe neuropathology, and postoperative seizure outcome were determined in each patient with SSAs. Nine (11%) of 81 patients with refractory temporal lobe seizures reported distinct SSAs as part of their habitual seizures. The most common manifestation of SSAs was tingling (eight of nine, 89%), but sensory loss (one of nine, 11%) and pain (one of nine, 11%) also were reported. Five patients had unilateral somatosensory symptoms, and four patients had bilateral somatosensory symptoms. Seizure origin was in the contralateral temporal lobe in four (80%) of five patients with unilateral SSAs, including all patients with unilateral SSAs affecting a limb. Partial temporal lobe resection produced complete seizure remission in all nine (100%) patients 1 year after surgery and in seven (78%) of nine patients 2 years after surgery. SSAs occur more frequently than previously appreciated in patients with refractory temporal lobe seizures and usually manifest as either unilateral or bilateral tingling. In patients with temporal lobe seizures, unilateral SSAs involving a limb suggest a seizure origin in the contralateral temporal lobe. The surgical outcome of TLE patients with SSAs is favorable. Thus the presence of SSAs should not serve as a deterrent to temporal lobe resection in patients with clearly defined TLE.

Characteristics of patients with spinal tuberculosis in a French teaching hospital

Objective. – To investigate the characteristics of patients managed for spinal tuberculosis at the rheumatology department of the Tours Teaching Hospital, France, between 1986 and 2003. Methods. – Retrospective chart review. The incidence, epidemiology, clinical features, imaging study findings, and diagnostic procedures were recorded. Results. – The annual incidence of spinal tuberculosis was stable throughout the study period. There were 24 patients, 15 women and nine men with a mean age of 61 years; 15 patients were of French descent, three were of Portuguese descent, two were Asian, and four were North-African. Risk factors consisted of alcohol abuse in one patient, diabetes in two patients, glucocorticoid therapy in two patients, and a history of tuberculosis in six patients; none of the patients had AIDS. The cervical spine was involved in two patients, the thoracic spine in 11 patients, and the lumbar spine in 12 patients. Mean time from symptom onset to diagnosis was 4.3 months (range, 1–12 months). Percutaneous vertebral biopsy established the diagnosis in 16 of the 20 patients who underwent this procedure. Conclusion. – The annual incidence of spinal tuberculosis remained unchanged throughout the study period and was not influenced by immigration or the AIDS epidemic. The typical patient was an elderly Caucasian woman of French descent. Reactivation of untreated or inadequately treated tuberculosis was probably the main mechanism.

The Pulmonary Status of Patients With Limited-Stage Small Cell Lung Cancer 15 Years After Treatment With Chemotherapy and Chest Irradiation

To describe pulmonary symptoms, signs, pulmonary function, and lung imaging studies in patients with limited-stage small cell lung cancer (SCLC) 2 to 15 years after receiving treatment with chemotherapy and chest radiotherapy. Retrospective review of clinical records and radiographic studies of patients treated in three different prospective combined-modality studies. Federal hospital. One hundred fifty-six patients with SCLC who were enrolled between 1974 and 1994. Patients with limited-stage SCLC treated on prospective therapeutic studies of combined chemotherapy and radiation therapy were identified. Pulmonary symptoms, physical findings, pulmonary function tests, arterial blood gas measurements, and chest imaging studies were assessed at baseline, and at 1 to 2 years, at 3 to 5 years, and at > 5 years following the initiation of treatment. Initial symptoms included cough in 84 (55%), dyspnea in 59 (39%), and sputum production in 26 (17%). Twenty-three patients lived beyond 5 years (15%) without evidence of recurrence. Seven of these 5-year survivors were without pulmonary symptoms. Pulmonary function test results showed no significant changes in percent predicted values for FVC, FEV(1), and FEV(1)/FVC ratio over the time periods reviewed. The percent predicted values for the diffusing capacity of the lung for carbon monoxide decreased from 71% before the start of treatment to 56% (p < 0.032) at 1 to 2 years. Values improved in most patients beyond 5 years after starting treatment. Radiologist interpretations of chest imaging studies were available for 17 of 23 patients surviving > 5 years. Most patients had minimal to no changes in imaging study findings beyond 5 years. Long-term survivors with limited-stage SCLC who were treated with combined chemotherapy and chest radiotherapy have minimal changes in pulmonary symptoms or function from 5 to 15 years after the start of treatment. A concern for late toxicity from combined-modality therapy should not dissuade clinicians from offering therapy with potentially curative result with minimal to no pulmonary dysfunction.

Intracranial lipomas: importance of localization

Intracranial lipomas are rare congenital malformations. They are usually pericallosal asymptomatic midline lesions. Other brain malformations are often seen in association with intracranial lipomas. We describe the findings of imaging studies, including computed tomography (CT), magnetic resonance (MR) imaging, and MR angiography, along with a brief review of the literature. The frequency and the spectrum of the associated brain malformations are also discussed. We retrospectively reviewed CT and MR findings of 24 patients (14 female, 10 male, mean age 38.6 years) diagnosed with intracranial lipoma between December 2000 and June 2004 in two different radiology departments. Seventeen of the patients were diagnosed using cranial MR and seven with cranial CT. The CT density of all lesions was measured. Imaging characteristics of lipomas, morphological findings and associated malformations were described. The intracranial locations of the lipomas were left-sided quadrigeminal cistern (n=3), right-sided quadrigeminal cistern (n=4), interpeduncular cistern (n=1), sylvian fissure (n=3), interhemispheric fissure (n=3), choroid plexus (n=2), intercerebellar fissure (n=3), corpus fornicis (n=1) and the periphery of the corpus callosum (n=4). Eighteen of the intracranial lipomas were tubulonodular; six were curvilinear. Associated anomalies were observed in six patients. All of the patients with sylvian fissure lipoma had seizures. The two preferential sites of intracranial lipomas were pericallosal and dorsal mesencephalic. Most intracranial lipomas are found incidentally during neuroradiological investigations. CT and MR examination usually lead to the diagnosis, because of the very low attenuation values of lipomas on CT and the short T1 and T2 on MR. Midline anomalies and other malformations such as aneurysms are frequently associated with intracranial lipomas. Careful radiologic evaluation is therefore necessary to evaluate associated pathologies. Sylvian fissure lipomas should be considered in the differential diagnosis of patients with epilepsy.

Hepatic involvement in larva migrans of Toxocara canis: Report of a case with pathological and radiological findings

Patients with the clinical syndrome of visceral larva migrans as a result of Toxocara species, have typical lesions in the liver consisting of granulomas that contain numerous eosinophils and often Charcot–Leyden crystals. This syndrome is rarely taken into account in patients with cholestatic syndrome, especially when hypereosinophilic reaction is absent. We report the case of a 47-year-old immunocompetent woman who presented with abdominal pain, in whom multiple focal liver lesions were discovered. She had come in contact with dogs. Diagnosis of toxocariasi was done. A good clinical response has been obtained by treating with thiabendazole. We present the findings of various imaging studies of the patient. This report shows that visceral larva migrans may be the cause of a chronic liver disease and should be suspected also in patients without fever and hypereosinophilia with cryptogenic cholestatic and focal liver lesions.

Structural brain changes in bipolar disorder using deformation field morphometry

The objective of this study was to investigate anatomical brain abnormalities in adult bipolar patients using a deformation field morphometry technique. Our sample consisted of 32 right-handed bipolar I patients (men/women=16/16) and 32 right-handed, age and gender matched healthy controls. Deformation field morphometry analysis was performed on three-dimensional spoiled gradient recalled acquisition images. We found gender-specific structural differences between bipolar patients and healthy individuals. Bipolar men had significantly larger lateral ventricles (especially pronounced in the left hemisphere) and smaller left dorsolateral prefrontal cortex than healthy male controls. Our results are complementary to the findings of functional imaging and post-mortem studies that demonstrate abnormalities in the dorsolateral prefrontal cortex in bipolar patients.

Chronic Knee Pain in a 21-Year-Old Woman

Chronic Knee Pain in a 21-Year-Old Woman

Imaging study findings in elastofibroma dorsi

Elastofibroma dorsi is a tumor or pseudotumor typically located under the tip of the scapula. It is far from uncommon in older individuals. The mass contains both fibrous tissue and fatty tissue. Imaging studies can provide the definite diagnosis in many cases. Computed tomography (CT) and magnetic resonance imaging (MRI) are particularly effective, as they visualize the characteristic layered pattern of fatty tissue (low-density by CT, high-signal on T1 images and intermediate signal on T2 images by MRI) and fibrous tissue (similar to muscle in terms of density by CT and signal intensity by MRI). To a lesser extent, plain radiographs and ultrasonography identify a number of suggestive features (location and layered structure). When the lesion exhibits typical imaging features and produces no symptoms, as is usually the case, further investigations are probably unnecessary.

The amygdala modulates the consolidation of memories of emotionally arousing experiences.

Converging findings of animal and human studies provide compelling evidence that the amygdala is critically involved in enabling us to acquire and retain lasting memories of emotional experiences. This review focuses primarily on the findings of research investigating the role of the amygdala in modulating the consolidation of long-term memories. Considerable evidence from animal studies investigating the effects of posttraining systemic or intra-amygdala infusions of hormones and drugs, as well as selective lesions of specific amygdala nuclei, indicates that (a) the amygdala mediates the memory-modulating effects of adrenal stress hormones and several classes of neurotransmitters; (b) the effects are selectively mediated by the basolateral complex of the amygdala (BLA); (c) the influences involve interactions of several neuromodulatory systems within the BLA that converge in influencing noradrenergic and muscarinic cholinergic activation; (d) the BLA modulates memory consolidation via efferents to other brain regions, including the caudate nucleus, nucleus accumbens, and cortex; and (e) the BLA modulates the consolidation of memory of many different kinds of information. The findings of human brain imaging studies are consistent with those of animal studies in suggesting that activation of the amygdala influences the consolidation of long-term memory; the degree of activation of the amygdala by emotional arousal during encoding of emotionally arousing material (either pleasant or unpleasant) correlates highly with subsequent recall. The activation of neuromodulatory systems affecting the BLA and its projections to other brain regions involved in processing different kinds of information plays a key role in enabling emotionally significant experiences to be well remembered.

Altered thalamic membrane phospholipids in schizophrenia: a postmortem study

Background Membrane lipids are important mediators of neuronal function. In a postmortem study, we measured membrane lipid components in the left thalamus of schizophrenic patients. This region might play an important role in the pathophysiology of schizophrenia and has not been studied thus far with respect to its membrane lipid composition. Methods The study included 18 chronic schizophrenic patients and 23 healthy control subjects. Using lipid extraction and thin-layer chromatography, we measured membrane phospholipids, galactocerebrosides 1 and 2, and sulfatides in thalamus homogenate. Results The main membrane phospholipid phosphatidylcholine and the major myelin membrane components sphingomyelin and galactocerebrosides 1 and 2 were found to be decreased in schizophrenic patients. In contrast, phosphatidylserine was increased. These lipid contents did not correlate with postmortem intervals and medication doses. There was no difference in the membrane phospholipids lysophosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidylglycerol or in sulfatides. Conclusions Our results confirm findings of magnetic resonance imaging, postmortem, and gene expression studies. They support the notion of an increased phospholipid breakdown in schizophrenia as a sign for decreased myelination and oligodendrocyte dysfunction.

Disorganised Memory after Right Dorsolateral Prefrontal Damage

Neurophysiological and functional brain imaging studies suggest the importance of dorsolateral area 9/46 for modality-independent working memory. However, the behavioural manifestations following isolated damage to this area have not been clearly outlined. Here, we describe the dramatic derangement of pragmatic memory after circumscribed lesion of the right area 9/46. A 52 year-old woman had suffered a traumatic brain injury 13 years ago and sought help for what she thought was a severe memory disorder. She regularly missed appointments and had gradually lost all her friends. She had tried different strategies to compensate for her memory problem, such as writing notes on her wrist or using electronic organizers. Intelligence, attention, verbal long-term memory, and executive functions were normal. Furthermore, experimental exploration demonstrated intact time estimation, attribution of memories to ongoing reality, and anticipation of outcomes. However, she failed to rehearse and manipulate information in working memory (n-back task), confirming the findings of functional imaging studies that the mid-dorsolateral prefrontal cortex is involved in mental manipulation of information. This case exemplifies that an isolated lesion of the right area 9/46 may induce severe failure to schedule actions and memory retrieval, a disorder leading to severely disorganised behaviour and disability.

Inhibitory interhemispheric visuovisual interaction in motion perception.

Findings of an earlier functional magnetic resonance imaging (fMRI) study that coherent motion stimulation of the right or left visual hemifield exhibited negative signal changes (deactivations) in the primary visual cortex and the lateral geniculate nucleus contralateral to the stimulated hemisphere were evaluated to determine the functional significance of this contralateral inhibition of the visual system. Fourteen subjects participated in a psychophysical study on the perception of single object motion (0.4 degrees /s) in one visual hemifield with or without concurrent coherent motion stimulation of the contralateral hemifield. Mean detection times for horizontal object motion (0.5 +/- 0.19 vs. 0.61 +/- 0.22 s) and vertical object motion (0.53 +/- 0.19 vs. 0.72 +/- 0.34 s) were significantly prolonged during concurrent motion pattern stimulation in the contralateral hemifield. These data support the interpretation that the deactivation of neuronal activity in the visual system found by fMRI is associated with a functional decrement in the sensitivity needed to perceive motion and may reflect transcallosal attentional shifts between the two hemispheres.

FDG PET in suspected recurrent and metastatic prostate cancer

Development of an accurate non-invasive imaging technique to detect recurrent and metastatic prostate cancer is critical for the effective management of these patients. The purpose of our study was to determine the diagnostic utility of positron emission tomography with [F-18]fluorodeoxyglucose (FDG PET) in patients with suspected or known metastatic and recurrent prostate cancer. We performed 12 FDG PET scans in 12 men (age 65-81 years) with history of prostate cancer who had previously undergone radical prostatectomy (n=3) or prostate radiotherapy (n=9). Serum prostate specific antigen (PSA) level was elevated in all patients (5-206 ng/ml). Available correlative imaging studies included contrast-enhanced chest, abdomen and pelvis CT (n=8), bone scintigraphy (n=5), and radiography (n=2). PET findings were compared to the findings of the other imaging studies on a lesion-by-lesion basis in individual patients. Validation was by clinical or imaging follow-up for up to 1 year. PET findings were concordant with the findings of the other imaging studies in 7 patients. PET was discordant with the other imaging studies in 5 patients. PET demonstrated suspicious hypermetabolic pelvic lymph nodes in one patient with negative pelvis CT. PET underestimated the extent of osseous metastatic disease in the remaining 4 patients. FDG PET is limited in the detection of osseous metastatic lesions but may be useful in the detection of metastatic nodal and soft tissue disease.

Combination therapy for chronic invasive rhinocerebral aspergillosis in a clinically immunocompetent patient

Background: Adequate therapy for chronic invasive rhinocerebral aspergillosis in immunocompetent patients is controversial. The incidence of the disease is high in the Sudan and the Middle East. Misinterpretation of diagnostic criteria, failure to verify tissue invasion of fungi, and a lack of understanding of the pathophysiology of various forms of fungal rhinosinusitis lead to controversies in nomenclature, diagnosis, and therapy. Objective: The aim of this report was to detail the clinical presentation and the endoscopic and imaging study findings of a patient with invasive Aspergillus rhinosinusitis with endocranial and orbital extension. This patient was treated with surgical débridement and a combination of antifungal drugs and immunomodulatory therapy. Methods: Endoscopic débridement and high-dose liposomal amphotericin B, in combination with flucytosine and immunomodulators, were used to treat this patient. Results: After treatment, the patient experienced 3 years of disease-free follow-up. Conclusion: Surgical débridement and high-dose systemic combined antifungal therapy with immunomodulatory drugs produced an excellent long-term result for this apparently immunocompetent patient with extensive invasive fungal rhinosinusitis with cerebral and orbital involvement.

Pathophysiology of headache.

Clinical features of different headache syndromes have been described in great detail; however, its pathophysiology remains poorly understood. We review the latest findings in both human imaging studies and experimental animals to explain the possible mechanisms involved in the genesis of headache syndromes.

Imaging Findings of Retroperitoneal Ganglioneuroma

Purpose: To characterize the typical radiologic appearance of ganglioneuromas of the adrenal gland and extra-adrenal retroperitoneum. Materials and Methods: The findings of diagnostic imaging studies (CT, n=5; ultrasound, n=1) involving six patients aged 19-58 years with pathologically proven ganglioneuroma were retrospectively analyzed by three radiologist in terms of the lesions' size, shape, margin, location, CT attenuation (unenhanced/contrast-enhanced), necrosis, calcification, relationship with adjacent vessels, and US echogenicity. Results: The maximum diameter of the six tumors ranged from 10 to 14 (mean, 11.3) cm, and the margin was well-defined in all cases. The homogeneous or slightly heterogeneous attenuation demonstrated at unenhanced CT was less than that of muscle. Dense nodular calcification was present in one case. At contrast-enhanced CT, enhancement was poor (n=5), mild and septum-like, or delayed, heterogeneous and focal (n=3), or involved subtle foci (n=1). In no case was there evidence of necrosis or hemorrhage. Local invasion was absent, but adjacent vascular encasement (n=2) or displacement (n=2) occurred. Ultrasonic examination demonstrated low echogenicity and mild heterogeneity (n=1). Conclusion: A ganglioneuroma is an uncommon benign neural crest tumor which should be included in the differential diagnosis of a retroperitoneal mass which presents as a well-defined tumor, tend to encase or displace adjacent major blood vessels, and shows low attenuation at unenhanced CT and poor or septum-like focal enhancement at contrast-enhanced CT.

V1 activity is reduced during binocular rivalry.

During binocular rivalry, one of two incompatible monocular stimuli is erased from perceptual awareness for seconds at a time. To examine whether this "rivalry suppression" occurs in V1, we measured functional magnetic resonance imaging activity during binocular rivalry and compared it with those in the two reference conditions: one representing complete suppression and the other representing no suppression. We found that the amplitude of V1 activity during rivalry fell midway between those in the two reference conditions; the amount of V1 activity associated with the nondominant pattern was reduced by 48% to 77% during rivalry. The same pattern of results was obtained with meaningful rival targets (i.e., a human face and a house). In this work, using a different experimental protocol, we confirmed the findings of earlier imaging studies that neuronal events associated with binocular rivalry occur as early as V1. Furthermore, our findings extend those earlier findings by demonstrating robust neural suppression during binocular rivalry regardless of the stimulus complexity of the rivaling targets.

Neuroreceptor imaging in psychiatric disorders.

Molecular imaging, the study of receptors, transporters and enzymes, as well as other cellular processes, has grown in recent years to be one of the most active neuroimaging areas. The application of single photon emission tomography (SPECT) and positron emission tomography (PET) techniques to the study of psychiatric illness has lead to increased understanding of disease processes as well as validated, in vivo, theories of illness etiology. Within the field of psychiatry these techniques have been applied most widely to the study of schizophrenia. Studies within schizophrenia are largely limited to either the dopamine or serotonin system. This is due in large part to the availability of suitable radiotracers as well as the current theories on the etiology of the illness. Two basic study designs are used when studying schizophrenia using molecular imaging and make up the majority of studies reviewed in this manuscript. The first type, termed "clinical studies," compares the findings from PET and SPECT studies in those with schizophrenia to normal controls in an attempt to understand the pathophysiology of the illness. The second study design, termed "occupancy studies," uses these techniques to enhance the understanding of the mechanism of action of the medications used in treating this illness. This review will focus on the findings of molecular imaging studies in schizophrenia, focusing, for the most part, on the serotonin and dopamine systems. Emphasis will be placed on how these findings and techniques are currently being used to inform the development of novel treatments for schizophrenia.

Treatment options in pediatric epilepsy syndromes

ABSTRACT Recent evidence suggests that various epilepsy syndromes respond differently to antiepileptic drugs. It follows that a more precise diagnosis, together with a better understanding of AED mechanisms of action, enables them to be used more specifically, and therefore more effectively. Patient characteristics including age of onset, seizure frequency, EEG data and the findings of imaging studies, provide diagnostic pointers which enable the physician to reach a syndrome diagnosis and to choose the most appropriate AED for the individual patient. Home videotapes of paroxysmal events are becoming increasingly available and are often of great assistance. Parents should be encouraged to record their children's attacks. Careful history‐taking and correct interpretation of clinical data remain the cornerstones of accurate diagnosis and successful treatment. However, the specificity of antiepileptic drugs is relatively limited and often pharmacotherapy should start using an agent with a broad spectrum of activity appropriate for the primary seizure type. It is in fact common that several antiepileptic agents have similar or identical effectiveness for one particular form of epilepsy. Therefore, the eventual side effects and the greater or lesser difficulties in handling the drug play an essential role in the choice of a therapeutic agent. Polypharmacy should be avoided and surgery should be considered early for selected patients, particularly children, who fail to respond to an appropriate drug trial. Correct diagnosis and the first drug(s) used may have a crucial impact on the evolution of given epilepsy. One major emphasis in the management of epilepsy is on information that should be complete, adapted to the level of understanding, and objective, although given in a positive manner. The understanding and cooperation of children and their families is clearly decisive for the success of therapy, and this requires a confident relationship between the physician and the patient. Current knowledge, on antiepileptic drugs options in paediatric epilepsy syndromes, is discussed.

The spectrum of benign esophageal lesions: imaging findings.

Benign esophageal lesions occur in various diseases. Barium studies are useful for the evaluation of mucosal surface lesions but provide little information about the extramucosal extent of disease. Computed tomography and magnetic resonance imaging, on the other hand, permit the assessment of wall thickness, mediastinal involvement, adjacent lymphadenopathy, and distant spread. In diseases such as fibrovascular polyps, duplication cysts, scleroderma, trauma, caustic esophagitis, hiatal hernia, esophageal diverticulum, achalasia, and paraesophageal varices, the findings of imaging studies are specific, obviating the need for further invasive diagnostic work-up. The advent of helical computed tomography and its volume data set allows the acquisition of multiplanar images, and magnetic resonance imaging is useful both for this and for tissue characterization. Thus, multiplanar cross-sectional imaging further extends the role of imaging modalities to the evaluation of benign esophageal lesions. Through an awareness of the multiplanar cross-sectional appearances of various benign esophageal lesions, the radiologist can play an important role in the detection, diagnosis, further diagnostic planning, and treatment of the diseases in which they occur.