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N Ghanem

Publications and source records attributed to N Ghanem.

At least 19 recordsLinked to original sources
PubMed2006

Detection and characterization of benign focal liver lesions with multislice CT.

MDCT is a rapidly evolving technique that significantly improves CT imaging for several indications including depiction of focal benign lesions. Imaging mainly profits from improved longitudinal spatial resolution allowing high-quality non-axial reformations and 3D reconstructions and CT angiography as well as rapid accurate multiphase imaging with short breath-holding periods. This review provides an overview of the current status of MDCT with respect to liver imaging and the implications for characterizing benign focal liver lesions. MDCT currently allows the acquisition of thin slices in daily routine diagnostics providing an improved detection rate of small liver lesions. Whereas large benign focal liver lesions exhibit typical patterns of morphology, attenuation and perfusion, which also may be assessed with single-slice scanners, small lesions remain challenging even with MDCT, since the specific criteria for confident diagnosis become more ambiguous. Here, MR imaging provides more detailed information about tissue components and the availability of liver-specific contrast agents, adding further impact to this technique. With respect to dose considerations, the number of necessary multiphase scans as well as the application of very thin collimation should be strictly checked for each patient undergoing MDCT based on the individual clinical situation and question.

Adenoma, Liver Cell↗
PubMed2006

Evaluation of three different measurement methods for dural ectasia in Marfan syndrome.

AIM: Dural ectasia is a major diagnostic criterion for Marfan syndrome using the Ghent nosology. Our aim was to evaluate the efficacy of three different radiological methods previously proposed for the assessment of dural sac diameter in Marfan syndrome. METHODS: Marfan syndrome was diagnosed in our study using the Ghent criteria, disregarding dural ectasia as a criterion. Three proposed radiological methods were applied to measure dural sac diameter, examined for 41 patients (18 patients with and 23 without Marfan syndrome) by computed tomography or magnetic resonance imaging. RESULTS: Using Oosterhof's method, 94% of the patients with and 44% of the patients without Marfan syndrome fulfilled the criteria of dural ectasia. According to Villeirs, dural ectasia was diagnosed in 18% of the patients with and in none of the patients without Marfan syndrome. With Ahn's method, dural ectasia was found in 72% of the patients with and in 44% of the patients without Marfan syndrome. In only two patients with Marfan syndrome was dural ectasia diagnosed by all three methods. CONCLUSION: Our results reveal overt discrepancy between the three methods of assessing dural ectasia. Considering the key role played by dural ectasia in reinforcing the diagnosis of Marfan syndrome according to the Ghent nosology, a standardized and reliable method should be sought.

Adolescent↗
PubMed2006

Clinical and radiological findings after different treatment of odontoid fractures type Anderson II and III.

PURPOSE OF THE STUDY: In the period from 06/00 to 08/02, 31 patients with odontoid fractures type Anderson II and III were treated and stastically recorded. 25 patients were followed up; the progess of 24, documented in detail radiographically, were evaluated independently by a traumatologist and by a radiologist. The usual time of immobilization when treating odontoid fractures type Anderson type II and III with the halo-fixator is 12 weeks. For this 12 weeks that it is worn, objective assessment of bone healing is performed radiographically and the results critically considered in terms of the length of time that the halo-fixator should be worn and whether this duration should be altered on the basis of the clinical and radiological results obtained. MATERIALS AND METHODS: 16 patients with an odontoid fracture type Anderson type II were treated partly with a halo-fixator and partly by additional operative stabilization. 15 patients with a type III fracture were treated in a halo over 12 weeks. At the time of the accident the patients to be treated had to have conventional radiographic examination and a CT scan as well as a position check following reduction. After 4, 8 and 12 weeks radiographic and CT investigation was repeated. These findings were evaluated independently by a surgeon and a radiologist. The clinical follow-up was carried out using the VAS Score and, in addition, the general activity level before and after the accident was recorded in a similar way on the Tegner/Lysholm subjective activity score. RESULTS: In most cases, according to the CT scan, the osseous bridging decreased again between the 8th and 12th weeks, as defined by resorption zones seen during the fracture healing period. Radiological evidence of complete osseous bridging was only seen after 12 weeks in three cases. CONCLUSION: Conventional radiography does not seem to us to be the most suitable technical means to evaluate osseous healing in odontoid fractures. The CT is more reliable for this. According to our radiological results, osseous healing of different types of odontoid fractures takes more than 12 weeks. Despite of its known complications, the halo fixator is still a good instrument for the treatment of odontoid fractures.

Adult↗
PubMed2005

Diagnostic value of MRI in comparison to scintigraphy, PET, MS-CT and PET/CT for the detection of metastases of bone.

The initial localization of metastases in the bone in patients with solid tumors has a relatively good prognosis in comparison with visceral metastasization. The early detection of bone marrow metastases allows for a rapid initiation of therapy and a subsequent reduction in the morbidity rate. Modern MRI is superior to the 30-year-old skeletal scintigraphy and bone marrow scintigraphy with respect to sensitivity, specificity, as well as the extent of osteal metastasis. MRI provides substantial, therapy-relevant additional information. MSCT plays an important role in the management of cancer patients in clinical routine and gives an excellent survey of the axial skeleton by demonstrating osteolytic and osteoblastic metastases. Extensive comparative studies of MRI with 18F-FDG-PET and 18F-fluoride-PET have not yet been carried out. Whole body MRI is a very promising new staging method for the oncological diagnosis of solid tumors and the detection of osteal metastases. The adoption of 18F-FDG-PET and 18F-fluoride-PET FDG as well as the side by side PET-CT image fusion and the two in one PET/CT examinations appears to be slightly less sensitive to whole body MRI in the detection of osteal metastases. Larger, prospective multicenter studies are necessary to establish these as new, promising methods for the detection of osteal metastases.

Bone Neoplasms↗
PubMed2005

Experimental autologous osteochondral plug transfer in the treatment of focal chondral defects: magnetic resonance imaging signs of technical success in sheep.

PURPOSE: To describe the magnetic resonance imaging (MRI) signs of technically successful osteochondral plug transfer and to correlate the findings with histology using the Mankin score. MATERIAL AND METHODS: The study was done in a prospective animal experiment: 11 adult black-head sheep underwent surgical treatment with osteochondral plug transfer of a knee joint. The animals were killed 6 months later and MRI of the joints was done immediately. MRI was applied with a 1.5T MR scanner using a spin-echo (SE) T1-weighted, turbo spin-echo (TSE) T2-weighted with spectral fat suppression and a fat-suppressed 3D-spoiled gradient echo (GRE) sequence (manufacturer's acronym: FLASH) (TR 50.0 ms, TE 11.0 ms, flip 35 degrees). After MRI, all knee joints were dissected and a biopsy of the plug and the adjacent cartilage was taken. Classification of the cartilage biopsies was carried out in accordance with a modified Mankin score. RESULTS: Cartilage repairs with a hypointense cartilage signal in the FLASH 3D sequence were correlated with poor histological results (lower Mankin score). Histologically, the regions of cartilage with a hypointense signal showed a fibrocartilage-like repair tissue. Hyaline cartilage with well-defined layers had the same signal intensity in the FLASH sequence relative to adjacent hyaline cartilage. There were two plugs with a surface defect, graded as Outerbridge grade 1 in MRI and histology. Both had a poor outcome in the histologic Mankin score. Grade 2-4 lesions were not observed in the MRI study nor in the histologic study. CONCLUSION: MRI is a useful non-invasive tool for evaluating the morphologic status of osteochondral plug transfers. A good postoperative result of the cartilage repair was found histologically if an isointense cartilage signal of the graft was documented in the FLASH 3D sequence, and the graft had good congruity with the articular surface without defects.

Animals↗
PubMed2005

Serial high-resolution computed tomography imaging in patients with Wegener granulomatosis: differentiation between active inflammatory and chronic fibrotic lesions.

PURPOSE: To evaluate pulmonary pathologies in Wegener granulomatosis with sequential computed tomography (CT) in order to differentiate active inflammatory lesions from chronic fibrotic lesions. MATERIAL AND METHODS: Serial CT findings in 38 patients with Wegener granulomatosis were retrospectively analyzed (mean follow-up period, 21 months). The presence, extension, and distribution of the following findings were evaluated with CT: parenchymal nodules, masses, ground-glass attenuation, airspace consolidation, bronchial wall-thickening, bronchiectasis, linear areas of attenuation, pleural irregularities, pleural effusions, hilar and mediastinal lymphadenopathy. RESULTS: Observed in 92% of patients, nodules were the most common CT pathology. Areas of ground-glass attenuation, consolidation, masses of linear attenuation, and tracheal/bronchial wall-thickening were detected in 24%, 26%, 32%, 39%, and 68% of patients. At follow-up, the clearance of lesions was most consistent for areas of ground-glass attenuation (89%), masses (87%), and cavitated nodules (85%). In the follow-up scan, 58% of all nodules, 47% of pulmonary consolidations, and 66% of bronchial wall-thickening were completely resolved. Areas of bronchiectasis and septal/non-septal lines remained stable in 70% and 71% of patients. CONCLUSION: The majority of the lesions decreased or resolved completely with or without areas of linear attenuation. Ground-glass attenuation, cavitated nodules and masses appear to represent active inflammatory lesions. In most probability, areas of bronchiectasis and septal/non-septal lines more often represent chronic fibrotic changes rather than active inflammatory changes. In combination with clinical evaluation and bronchoscopy, CT assists in the assessment of disease activity.

Adult↗
PubMed2004

Impact of [18F]FDG-PET on the primary staging of small-cell lung cancer.

PURPOSE: The purpose of this study was to evaluate the impact of [18F]fluorodeoxy-D-glucose positron emission tomography (FDG-PET) on the primary staging of patients with small-cell lung cancer (SCLC). METHODS: FDG-PET was performed in 120 consecutive patients with SCLC during primary staging. In addition, brain examinations with both FDG-PET and cranial magnetic resonance imaging (MRI) or computed tomography (CT) were performed in 91 patients. Results of FDG-PET were compared with those of conventional staging procedures. FDG-PET detected markedly increased FDG uptake in the primary tumours of all 120 patients (sensitivity 100%). RESULTS: Complete agreement between FDG-PET results and other staging procedures was observed in 75 patients. Differences occurred in 45 patients at 65 sites. In 47 sites the FDG-PET results were proven to be correct, and in ten, incorrect. In the remaining eight sites, the discrepancies could not be clarified. In 14/120 patients, FDG-PET caused a stage migration, correctly upstaging ten patients to extensive disease and downstaging three patients by not confirming metastases of the adrenal glands suspected on the basis of CT. Only 1/120 patients was incorrectly staged by FDG-PET, owing to failure to detect brain metastases. In all cases the stage migration led to a significant change in the treatment protocol. Sensitivity of FDG-PET was significantly superior to that of CT in the detection of extrathoracic lymph node involvement (100% vs 70%, specificity 98% vs 94%) and distant metastases except to the brain (98% vs 83%, specificity 92% vs 79%). However, FDG-PET was significantly less sensitive than cranial MRI/CT in the detection of brain metastases (46% vs 100%, specificity 97% vs 100%). CONCLUSION: The introduction of FDG-PET in the diagnostic evaluation of SCLC will improve the staging results and affect patient management, and may reduce the number of tests and invasive procedures.

Brain Neoplasms↗
PubMed2004

[Whole-body MRI in comparison to skeletal scintigraphy for detection of skeletal metastases in patients with solid tumors].

PURPOSE: The aim of this study was to compare the diagnostic efficacy of whole-body magnetic resonance imaging (WB-MRI) as a new and rapid examination technique with skeletal scintigraphy for detection of skeletal metastases from solid tumors. MATERIAL AND METHODS: In 129 patients with solid malignant tumors, WB-MRI was performed for individual comparison with skeletal scintigraphy. Examinations were performed with the innovative AngioSURF rolling table with integrated phased array surface coil and coronary TIRM sequences for different body regions. RESULTS: The results for WB-MRI and skeletal scintigraphy were concordant in 81% of the cases, whereby both procedures excluded skeletal metastases in 43%. WB-MRI and skeletal scintigraphy demonstrated skeletal metastases in 38% of the cases, whereby WB-MRI provided more comprehensive findings in 45%. In 12% of the cases, skeletal scintigraphy was superior to WB-MRI and in 19% the findings were discordant, whereby WB-MRI detected skeletal metastases in 15 cases which had not been found on skeletal scintigraphy. In nine cases, skeletal scintigraphy was positive when the WB-MRI was negative. In 60% of the cases, WB-MRI evidenced tumor-associated findings. CONCLUSION: WB-MRI represents a promising new staging technique for detection of skeletal metastases, which is more sensitive in many cases than skeletal scintigraphy in detecting and assessing the extent of skeletal metastases-and tumor-associated findings that are relevant for treatment strategy.

Adolescent↗
PubMed2004

Characteristics of neonates with isolated rectal bleeding.

OBJECTIVE: To determine the characteristics of full term and preterm neonates with isolated rectal bleeding (IRB), and to follow the outcome of these low risk patients. DESIGN: A retrospective case-control study consisting of 147 cases (83 full term and near term infants and 64 preterm infants) and 147 controls in a single institution. RESULTS: A feeding regimen that did not include breast milk was the only variable found to predict IRB. In full term and near term babies (gestational age >/= 35 weeks), 52.6% of the study group were breast fed compared with 83.1% of the controls (p < 0.0001). In preterm babies (gestational age </= 34 weeks), 45.9% of the study group were breast fed compared with 74.2% of the controls (p = 0.0014). No obvious systemic infection cause was detected. None of the patients showed clinical or radiological deterioration in the days after diagnosis of IRB. CONCLUSIONS: The outcome of a group of low risk neonates with IRB was excellent. It is questionable whether antibiotic treatment is required and feeding needs to be stopped. Breast feeding, even if only partial, should be encouraged.

Birth Weight↗
PubMed2003

[Diverticulosis: the dimensions of a growing problem].

The etiology of diverticulitis remains unexplained. One hypothesis postulates that a diet low in fiber results in low-volume feces, which in turn leads to a segmental increase in muscle tone with bulging of the mucosa. Diverticulitis then occurs through micro-/macroperforation of the resulting diverticulum. Four grades are distinguished ranging from local mesenteric inflammation (grade I) to fecal peritonitis (grade IV). Asymptomatic diverticulitis requires no treatment. Diverticular bleeding must be carefully distinguished from upper gastrointestinal tract bleeding, carcinoma, and angiodysplasia. In the case of symptomatic diverticulitis ("left-sided appendicitis") a differentiation must be made between the acute and chronic forms. The diagnosis of diverticulitis is based on laboratory findings, x-rays and CT scans. If chronic diverticulitis is suspected, it is important to exclude carcinoma of the colon. Whether treatment should be surgical or conservative will depend on the severity of the condition, and on the complications that may be expected with conservative therapy.

Adult↗
PubMed2003

Background suppression using magnetization preparation for contrast-enhanced 3D MR angiography of the pelvic and lower leg arteries.

PURPOSE: To develop and evaluate non-slab-selective magnetization preparation in contrast-enhanced 3D-MR angiography. METHODS: An ultrafast spoiled mr angiography sequence (FLASH) with non-selective inversion prepulses for background suppression was implemented on a 1.5 T MR system. In 11 patients gadobenate dimeglumine-enhanced mr-angiography of the pelvic and lower leg arteries was performed using the AngioSURF device. Source data was evaluated for contrast-to-noise-ratio, image quality and the extent of background suppression. RESULTS: Background suppression and selective vessel contrast was excellent in all vascular levels. The mr protocol was comfortable and easy-to-handle. Abandonment of precontrast-series acquisition simplified the examination procedure markedly. CONCLUSIONS: Magnetization preparation provides efficient suppression of the background signal in contrast-enhanced 3D mr angiography of the pelvic and lower leg arteries. Since no subtraction technique is needed, moving-bed and whole body MRA-protocols can be simplified significantly.

Adult↗
PubMed2003

[Electronic distribution of patient records and images through PACS: implementation of data protection at the University Hospital in Freiburg].

In large installations of a Picture Archiving and Communication System (PACS), data protection becomes an issue. Above all, not every employee should have access to all data stored in the system. At the Freiburg University Hospital, we developed a concept of dynamic assignment of authorization, assuring that every physician is authorized to the data of all patients under his care. We describe the technical implementation of data protection developed for the integration of PACS and electronic patient records in Freiburg. The system was installed in January 2001 and the experience of its two years in operation is reported.

Computer Security↗
PubMed2002

Diagnosis of the hypothenar hammer syndrome by high-resolution contrast-enhanced MR angiography.

Our objective was to describe the imaging features of hypothenar hammer syndrome using minimally invasive contrast-enhanced MR angiography in comparison with oscillography study. In five patients with hypothenar hammer syndrome Gd-BOPTA-enhanced elliptically reordered 3D pulse sequence MR was compared with oscillography findings and clinical symptoms focusing on angiographic appearance of vessel injury, distribution pattern of hand vasculature and joining branches between the radial and ulnar artery supply. All patients showed segmental occlusion at the site of trauma impact with varying involvement of the superficial palmar arch, common volar digital arteries. Embolic disease was present in 50% of patients and could be clearly identified with MRA. Good correspondence was found between angiographic appearance including the presence of collaterals, clinical symptoms and oscillography. Bilateral comparison was helpful in distinguishing between vessel variants and pathology. Bilateral Gd-BOPTA-enhanced MR angiography is a minimally invasive method to depict clearly the localization and extent of vessel injury in hypothenar hammer syndrome providing valuable information about distribution pattern of hand vasculature and presence of collaterals; however, no flow data can be obtained.

Adult↗
PubMed2002

[Relevance of magnetic resonance imaging for the staging and follow up of lymph node pathologies in adults with primary malignant lymphomas].

Lymph node histology and staging with cross sectional imaging remains basis for the treatment planning in primary malignant lymphoma. Contrast enhanced computed tomography is considered to be gold standard. However, MRI is equally able to provide staging and follow up in the same quality as helical CT, as several studies and clinical experience show. MRI is considered as the superior imaging modality for extranodal lymphoma. Advantages of MRI are that it works without ionizing radiation and contrast media;however, MRI is more expensive and time consuming. However, both imaging modalities are limited by the fact that the differentiation of affected and non affected lymph nodes is based on size only. Also the results of recent clinical studies with USPIOs (SINEREM((R):)) for intravenous MR lymphography in primary malignant lymphoma do not look promising. Despite these disadvantages of MRI, for young patients with malignant lymphoma radiation protection should be taken into account because of frequent imaging in staging and follow up.

Adult↗
PubMed2002

Tracheal stenosis caused by false aneurysm of the right subclavian artery.

The development of tracheal stenosis following insertion of a central venous catheter is a rare complication of this procedure. We present the case of an 81-year-old woman, who suffered acute onset of dyspnea, stridor and dysphagia 4 weeks after coronary artery bypass surgery. Investigations revealed a false aneurysm of the right subclavian artery, compressing the trachea and the oesophagus. The iatrogenic lesion was caused by the insertion of a central venous catheter via the right subclavian route. By the time symptoms developed the catheter had already been removed.

Aged↗
PubMed2002

Epithelioid angiosarcoma of the aorta.

Primary malignant tumors of the aorta are extremely rare. Review of the literature indicates that there are nearly 100 recorded cases of primary malignant tumors of the aorta. The purpose of this article is to present an additional case of the primary malignant tumors of the aorta which initially has been misinterpretated as atherosclerosic disease. This aortic tumor was of endothelial origin and immunohistochemical studies classified the tumor as an epithelioid angiosarcoma. The treatment resulted in an abdominal aortic repair. MRI of the spine revealed multifocal metastatic disease of the axial skeleton and a subsequent chemotherapy was performed. The patient died 17 months after the initial diagnosis.

Aorta, Thoracic↗
PubMed2002

[Image quality of paper prints compared to film copies in CT investigations].

PURPOSE: Evaluation of image quality of paper prints in routine CT investigations. METHOD: The image quality of paper prints from 104 CT scans of daily routine investigations was analysed by three observer three observers according to a five-point ranking scale for contrast, grey level, spatial resolution, and subjective confidence in correct evaluation. Each study was rated "acceptable" or "not acceptable for documentation". RESULTS: In 312 ratings the mean grade for contrast was 2.7, for grey levels 3.2, and for spatial resolution 3.3. Grades ranged from 1 = very good to 5 = insufficient. Subjective confidence in correct evaluation was rated as "certain" in 77.4 %, "likely" in 18.4 % and "impossible to evaluate" in 4.2 % of cases. 93.7 % of printed CT images were rated "acceptable for documentation". CONCLUSION: Image quality of paper prints does not reach the quality of laser films concerning its contrast, grey levels, and spatial resolution. Nevertheless, paper prints are acceptable for documentation of findings in most CT investigations. A high confidence in correct evaluation was found. Limitations are found in documentation of small coin lesions of the lung and ischemic lesions of the neurocranium.

Humans↗