Volkmar Jacobi

Fluorine-18 FDG positron emission tomography for imaging of hepatocellular carcinoma

Objective:The detection of increased fluorine-18 fluorodeoxyglucose (18F-FDG) uptake by positron emission tomography (PET) is based on the enhanced glucose metabolism of tumor cells. Because the detection and staging of hepatocellular carcinoma (HCC) in patients with liver cirrhosis can be difficult, we prospectively evaluated the sensitivity of 18F-FDG PET in 14 consecutive patients with HCC.Methods:Whole body and regional 18F-FDG PET of the liver were obtained. The results were compared with ultrasonography, contrast-enhanced, helical CT, histological grading, p53 protein expression of HCC, and serum α-fetoprotein (AFP) level.Results:In 7 patients PET demonstrated increased tumor 18F-FDG uptake, whereas HCC was not distinguishable from nonmalignant liver tissue in 7 other patients. Hepatic lesions were detected by ultrasonography in all patients, whereas only 11 of 14 HCCs could be identified by CT. In 3 patients extrahepatic spread was demonstrated by 18F-FDG PET. Patients with increased tumor 18F-FDG uptake had significantly larger hepatic lesions and higher serum AFP levels than those with normal 18F-FDG uptake. Lesions could be visualized by 18F-FDG PET in 7 of 8 patients with moderately or poorly differentiated HCC, whereas none of the six well-differentiated tumors was detected. Two patients with strong p53 expression demonstrated increased tumor 18F-FDG uptake and extrahepatic metastases.Conclusions:The sensitivity of 18F-FDG PET for the imaging of HCC is low. Nevertheless, in patients with moderately or poorly differentiated HCC, tumors >5 cm, or with markedly elevated AFP levels 18F-FDG PET may contribute to an effective noninvasive staging.

Comparison of Histopathological Analysis, Culture, and Polymerase Chain Reaction Assays to Detect Invasive Mold Infections from Biopsy Specimens

BACKGROUND With the advent of new antifungal agents, the identification of a causative pathogen is crucial to guide the antifungal treatment of invasive mold infection. However, tissue cultures often fail to grow a fungal pathogen in cases of suspected mold infection. METHODS In a prospective multicenter study, we compared the results of histopathological analysis, culture, and 2 seminested polymerase chain reaction assays identifying Aspergillus species and Zygomycetes as causative agents of invasive mold infections using respiratory tract biopsy samples obtained from 56 immunocompromised patients who had suspected mold infection. RESULTS Mold hyphae were detected histopathologically in 27 (48%) of the tissue specimens. Hyphae corresponded to either aspergillosis (n=18) or zygomycosis (n=6) or could not be further specified (n=3). A mold was cultured from 14 of 18 samples with aspergillus hyphae, 2 of 6 samples with Zygomycetes hyphae, and 1 of 3 samples with unspecified hyphae. Polymerase chain reaction was superior to culture in detecting the infecting mold (26 of 27 samples vs. 17 of 27 samples, respectively; P=.006) from histopathologically positive samples. Genus or species identification by sequencing of the polymerase chain reaction products were in accordance with culture results in 16 of 18 culture-positive samples. Both polymerase chain reaction assays failed to detect fungal DNA in 1 sample that had unspecified hyphae and negative culture results. CONCLUSION The PCR assays offer a reliable etiologic diagnosis that is superior to culture in patients with proven invasive mold infection. This may improve patient management through tailored antifungal therapy when cultures fail to grow a pathogen.

Traumatic injuries of the pelvis and thoracic and lumbar spine: does thin-slice multidetector-row CT increase diagnostic accuracy?

The objective is to evaluate different multidetector-row CT (MDCT) strategies for adequate classification of spinal and pelvic injuries. Seventy intubated patients after multiple trauma underwent conventional radiography (CR) and MDCT. Examinations included the pelvis (P), the lumbar spine (LS) and the thoracic spine (TS). Conventional radiographs, 3-mm (CT5) and 5-mm scans (CT3) and 3-mm and 5-mm scans combined with MPR (CT3R/CT5R) were compared to surgery, autopsy and clinical course. MDCT led to significantly better results than CR (P<0.01). Correlation coefficients were r=1.0 (CT3R), r=0.96 [TS] to r=1.0 [P/LS] (CT5R), r=0.8 [P] to r=1.0 [TS] (CT3), r=0.80 [P] to r=0.86 [TS] (CT5) and r=0.3 [TS] to r=0.69 [P] (CR). Fractures were identified by CT3R in 100% of cases, by CT5R in 95%, by CT3 in 90% [P]−100% [TS], by CT5 in 83.3% [LS]−90% [P] and by CR in 57.1% [TS]−87.2% [P]. Unstable fractures were identified in 100% by CT3R, CT5R and CT3, 85.7% [TS]−100% [P/LS] by CT5 and 57.1% [TS]−80% [P] by CR. Only overlapping thin-slice multiplanar reformation allows for an adequate classification of spinal and pelvic injuries and thus is highly emphasized in patients after severe blunt trauma.

Cluster of pulmonary infections caused by Cunninghamella bertholletiae in immunocompromised patients.

Cunninghamella bertholletiae is a rare cause of pulmonary mucormycosis. We describe a cluster of invasive pulmonary infections caused by C. bertholletiae in 4 immunocompromised patients that occurred during a 2-year period at 1 center. Three of the patients were receiving antifungal prophylaxis with itraconazole. Presenting symptoms were fever unresponsive to antibacterial chemotherapy, hemoptysis, and infiltrates on chest radiograms. Three patients were treated with liposomal amphotericin B. Only 1 patient survived.

Pulmonary lymphangioleiomyomatosis: high-resolution CT findings.

Abstract. Lymphangioleiomyomatosis (LAM) of the lung is a very rare disease. There are obvious discrepancies in the literature concerning the appearance of LAM on CT scans of the lung. This study adds the imaging findings of 11 patients and demonstrates how the imaging findings changed over time in four patients. Twenty-two CT examinations, and radiographs that had been obtained close to the CT examinations, of 11 patients with LAM confirmed by open lung biopsy were retrospectively evaluated with particular attention to the size of cystic lesions and wall thickness. Furthermore the CT scans were analysed for the type of pulmonary infiltration process and its distribution, presence or absence of pleural effusion, pneumothorax and lymph node enlargement. Clinical and CT follow-up studies were available in four patients. The CT scans revealed an increase in the interstitial pattern in all patients. Architectural distortion was seen in two patients and cystic lesions were present in all. The size of the cysts varied from small lesions to bullous emphysema. The cystic lesions revealed a wall thickness up to 2 mm but a wall was not perceptible in all. Pneumothorax was seen in only two patients; pleural effusion was seen in two patients. CT examination of patients with LAM reveals neither a uniform nor a pathognomonic appearance. In the early stages of LAM or in cases with interstitial changes the differential diagnosis of centrilobular emphysema or idiopathic pulmonary fibrosis seems to be more difficult than most authors believe.

CT findings in extensive tracheobronchial amyloidosis

Abstract. Primary pulmonary amyloidosis is a rare disorder that appears in three forms: tracheobronchial, nodular parenchymal, and diffuse parenchymal. We report the case of a 46-year-old women with extensive tracheobronchial amyloidosis which presented with a 2-year history of dyspnea and with signs of severe fixed obstruction in pulmonary function tests. Computed tomography of the thorax demonstrated marked thickening of the trachea and the central bronchial tree with substantial narrowing of the main, lobar, and segmental bronchi. Transbronchial specimen showed typical birefringence under polarizing microscope after staining with Congo Red. We did not find hints for systemic amyloidosis.

Value of a laser guidance system for CT interventions: a phantom study

Abstract. The aim of this study was to check the handling and usefulness of a laser puncture system. The laser has tacking optics and is fastened to a sledge with angle graduation. The sledge runs on a bar fixed to the computerized tomograph (CT) parallel to the scan level. By means of a phantom, three experienced and seven inexperienced physicians made punctures with and without laser, using varying angles in single and double angulation. The distance from needle tip to target was measured. The handling of the puncture system proved to be problem-free. With both single and double angulation, the measurement differences with and without support were so small among experienced puncturers that there was no significant difference, with the exception of one double angulation (10 °/45 °). Among the beginners, there was a significant difference (P < 0.001, P < 0.05), with both single and double angulation. The accuracy of the beginners improved with use of the laser; experienced puncturers may profit from practice with small and hard-to-reach focuses. In terms of educational benefits, the laser guidance system offers great advantages and increased confidence for beginners.

Radiation dose and image quality of X-ray volume imaging systems: cone-beam computed tomography, digital subtraction angiography and digital fluoroscopy

AbstractObjectiveRadiation dose and image quality estimation of three X-ray volume imaging (XVI) systems.MethodsA total of 126 patients were examined using three XVI systems (groups 1–3) and their data were retrospectively analysed from 2007 to 2012. Each group consisted of 42 patients and each patient was examined using cone-beam computed tomography (CBCT), digital subtraction angiography (DSA) and digital fluoroscopy (DF). Dose parameters such as dose–area product (DAP), skin entry dose (SED) and image quality parameters such as Hounsfield unit (HU), noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were estimated and compared using appropriate statistical tests.ResultsMean DAP and SED were lower in recent XVI than its previous counterparts in CBCT, DSA and DF. HU of all measured locations was non-significant between the groups except the hepatic artery. Noise showed significant difference among groups (P < 0.05). Regarding CNR and SNR, the recent XVI showed a higher and significant difference compared to its previous versions. Qualitatively, CBCT showed significance between versions unlike the DSA and DF which showed non-significance.ConclusionA reduction of radiation dose was obtained for the recent-generation XVI system in CBCT, DSA and DF. Image noise was significantly lower; SNR and CNR were higher than in previous versions. The technological advancements and the reduction in the number of frames led to a significant dose reduction and improved image quality with the recent-generation XVI system.Key Points• X-ray volume imaging (XVI) systems are increasingly used for interventional radiological procedures. • More modern XVI systems use lower radiation doses compared with earlier counterparts. • Furthermore more modern XVI systems provide higher image quality. • Technological advances reduce radiation dose and improve image quality.

Older patients with high-risk fungal infections can be successfully allografted using non-myeloablative conditioning in combination with intensified supportive care regimens

Leukaemic patients with advanced disease and severe fungal infections as well as older patients with substantial co‐morbidity are usually excluded from conventional allotransplantation because of increased morbidity and mortality. We approached allogeneic transplantation in four patients with a median age of 62 years (one chronic myeloid leukaemia in blast crisis, one high‐risk acute myeloid leukaemia (AML) in first complete remission (CR1), one AML in 2nd relapse, one AML in CR2 with pre‐existing fungal lung infections (two aspergillus, two mucor) and additional co‐morbidity (diabetes n = 2, aortic aneurysm n = 1, arterial sclerosis n = 2) by combining non‐myeloablative conditioning with an intensified supportive care regimen, including amphotericin B and 4–12 (median 9) prophylactic granulocyte transfusions from granulocyte colony‐stimulating factor (G‐CSF)‐stimulated volunteer donors. G‐CSF was also given to patients until neutrophil recovery. All four patients recovered to a neutrophil count of 0·5 × 109/l after a median of 11·5 d (range 11–13 d). Prophylactic granulocyte transfusions also reduced the need for platelet transfusions and minimized mucositis. All patients were discharged at a median of 25 d (range 18–59 d) and are alive and well after a median follow‐up of > 390 d (range 336–417 d) without evidence of leukaemia. Regression of the fungal lesions was documented in three patients, with a slight progression detected by computerized tomography scan of the chest in one patient. We conclude that pulmonary fungal infections are not a contraindication for allogeneic stem cell transplantation, if non‐myeloablative conditioning regimens are used in combination with granulocyte transfusions, intravenous amphotericin B and G‐CSF.

Multislice CT and CT angiography for non-invasive evaluation of bronchopulmonary sequestration.

Bronchopulmonary sequestration (BPS) is a rare congenital anomaly due to disturbed embryogenesis with a surplus budding of the lungs. BPS has no communication with the bronchial system. In most cases the blood supply of the sequestration is systemic via the aorta. There are two types of BPS: intralobar sequestration without its own pleural covering and extralobar sequestration with a separate pleura. They are clinically manifested in different ways. Sequestration normally occurs in the left lower lobe. The venous drainage often occurs via the pulmonary veins, producing a large shunt volume. The clinical symptoms are caused by recurrence of infection because of extensive therapy resistance, and rarely by haemoptysis.