Biomedical subjects

V Jacobi

Publications and source records attributed to V Jacobi.

At least 19 recordsLinked to original sources

PubMed2006

[Magnetic resonance imaging in orthopaedic medicine].

Magnetic resonance imaging (MRI) is an established diagnostic tool in orthopaedics. Superior soft tissue contrast, lack of ionised radiation and free slice orientation are the key points for optimal evaluation of joint structures, muscles and ligaments. Application of contrast agents improves the detection of inflammation and tumour tissue. However, measuring and interpretation of magnetic resonance imaging is a challenge both for orthopaedists and radiologists. Basic requirements for good diagnosis are clinical findings, plain radiographs and a clear indication. This report provides information about the method of magnetic resonance imaging, artefacts, indications, risks and drawbacks as well as limitations of this method that necessitate alternative imaging modalities.

Contrast Media↗

PubMed2006

Diagnosis of invasive aspergillosis and mucormycosis in immunocompromised patients by seminested PCR assay of tissue samples.

Aspergillosis and mucormycosis are the most common mold infections in patients with hematological malignancies. Infections caused by species of the genus Aspergillus and the order Mucorales require different antifungal treatments depending on the in vitro susceptibility of the causative strain. Cultures from biopsy specimens frequently do not grow fungal pathogens, even from histopathologically proven cases of invasive fungal infection. Two seminested PCR assays were evaluated by amplifying DNA of zygomycetes and Aspergillus spp. from organ biopsies of 21 immunocompromised patients. The PCR assays correctly identified five cases of invasive aspergillosis and six cases of mucormycosis. They showed evidence of double mold infection in two cases. Both assays were negative in five negative controls and in two patients with yeast infections. Sequencing of the PCR products was in accordance with culture results in all culture-positive cases. In six patients without positive cultures but with positive histopathology, sequencing suggested a causative organism. Detection of fungal DNA from biopsy specimens allows rapid identification of the causative organism of invasive aspergillosis and mucormycosis. The use of these PCR assays may allow guided antifungal treatment in patients with invasive mold infections.

Adult↗

PubMed2006

[The infammatory pseudotumour -- an unusual liver tumour].

We report on a 49-year-old male patient who was suspected to have a malignant liver tumour with enlarged perihepatic lymph nodes because of CT and ultrasound scanning. To verify the diagnosis and procure a histological specimen, the patient underwent laparotomy. Histologically, an inflammatory pseudotumour could be confirmed. This is a rare disease which can present with fever, abdominal pain, vomiting and weight loss indicating malignancy or abscess. The definite diagnosis is often only verified by surgery.

Biopsy, Fine-Needle↗

PubMed2006

Automated detection of lung nodules in multidetector CT: influence of different reconstruction protocols on performance of a software prototype.

PURPOSE: To evaluate the accuracy of software for computer-aided detection (CAD) of lung nodules using different reconstruction slice thickness protocols in multidetector CT. MATERIALS AND METHODS: Raw image data sets for 15 patients who had undergone 16-row multidetector CT (MDCT) for known pulmonary nodules were reconstructed at a reconstruction thickness of 5.0, 2.0 and 1.0 mm with a reconstruction increment of 1.5, 1.0 and 0.5 mm, respectively. The "Nodule Enhanced Viewing" (NEV) tool of LungCare for computer-aided detection of lung nodules was applied to the reconstructed images. The reconstructed images were also blinded and then evaluated by 2 radiologists (A and B). Data from the evaluating radiologists and CAD was then compared to an independent reference standard established using the consensus of 2 independent experienced chest radiologists. The eligible nodules were grouped according to their size (diameter > 10, 5 - 10, < 5 mm) for assessment. Statistical analysis was performed using the receiver operating characteristic (ROC) curve analysis, t-test and two-rater Cohen's Kappa co-efficient. RESULTS: A total of 103 nodules were included in the reference standard by the consensus panel. The performance of CAD was marginally lower than that of readers at a 5.0-mm reconstruction thickness (AUC = 0.522, 0.517 and 0.497 for A, B and CAD, respectively). In the case of 2.0-mm reconstruction slices, the performance of CAD was better than that of the readers (AUC = 0.524, 0.524 and 0.614 for A, B and CAD, respectively). CAD was found to be significantly superior to radiologists in the case of 1.0-mm reconstruction slices (AUC = 0.537, 0.531 and 0.675 for A, B and CAD, respectively). The sensitivity at a reconstruction thickness of 1.0 mm was determined to be 66.99 %, 68.93 % and 80.58 % for A, B and CAD, respectively. The time required for detection was shortest for CAD at reconstruction slices of 1.0 mm (mean t = 4 min). The performance of radiologists was greatly enhanced when using CAD: sensitivity 91.26 % and 94.17 % for CAD+A and CAD+B, respectively (AUC = 0.889 and 0.917). CAD was most advantageous in the detection of nodules < 10 mm. CONCLUSION: At a 1.0-mm reconstruction thickness, CAD's ability to detect nodules < 10 mm is superior to that of radiologists and its relatively short evaluation time makes it a viable second reader.

Diagnosis, Computer-Assisted↗

PubMed2006

[Staging of prostate cancer: value of the combined information of endorectal MRI, biopsy Gleason score, and preoperative PSA level].

PURPOSE: To evaluate the predictive value of MR imaging criteria, the biopsy Gleason score, and preoperative PSA levels for differentiating between T2 and T3 prostate carcinomas. MATERIALS AND METHODS: Endorectal MR images of 81 patients (median age: 65 years, range: 48 to 81 years) who had biopsy-proven prostate cancer and underwent a radical prostatectomy were analyzed retrospectively. The existence of different imaging features were recorded for each patient. A radiological analysis comprising all used imaging criteria was also performed for every patient. Optimal cut-off levels for the biopsy Gleason score and preoperative PSA levels were obtained using ROC analyses. Subsequently, a logistic regression analysis was performed to identify features which make a significant contribution to the prediction of the tumor stage. RESULTS: Histological examination showed that 24 patients (29.6 %) had a T3 tumor and 57 patients (70.4 %) had a T2 tumor. The mean preoperative PSA level was 9.4 ng/ml (+/- 7 ng/ml), and the median Gleason score was 6 with a range of 4 to 8. The radiological judgment comprising all imaging criteria led to a sensitivity of 54.2 % and specificity of 79 % for the detection of a T3 tumor. The obliteration of the rectoprostatic angle (regression coefficient B = 2.30; standard error (se) = 0.80; p = 0.002) and the biopsy Gleason score (B = 1.16; se = 0.3; p = 0.001) were the parameters with the highest independent predictive value for the diagnosis of an extracapsular tumor spread. The other radiological criteria and the preoperative PSA level were not statistically significant. A combination of the parameters "obliteration of the rectoprostatic angle" and "biopsy Gleason score" led to a sensitivity and specificity of 75 % and 79 %, respectively (existence of one parameter sufficient). The optimal cut-off value was a Gleason score of 7 for the differentiation between T2 and T3 prostate carcinomas. CONCLUSION: In our study, only the criteria "obliteration of the rectoprostatic angle" and "biopsy Gleason score" were of predictive value for the diagnosis of a T3 prostate carcinoma. The other MR imaging criteria and the preoperative PSA levels had no additional benefit.

Aged↗

PubMed2006

[Variation in X-ray dose quantity using an amorphous selenium based flat-panel detector -- a study on the dose reduction rate up to the limit of diagnostical utilization].

PURPOSE: To evaluate the diagnostic quality and minimum required dose to obtain acceptable images for diagnostic purposes in the field of musculoskeletal radiology. MATERIALS AND METHODS: A critical comparison of the image quality produced by a novel flat panel detector and the conventional screen/film system using a contrast-detail phantom was performed in phase I. Images from both systems were obtained with the same dose and displayed with similar contrast and density. In phase II images of significant anatomical structures in cadaver extremities obtained using the digital detector system and the standard film/screen system were critically evaluated. After a successive reduction in the X-ray dose for 84 patients in phase III, eight independent radiologists compared the image quality of the screen/film system to that of the novel flat panel detector. RESULTS: Phases I and II revealed a difference in the image quality achieved by the standard screen/film system and the digital detector system to the advantage of the digital detector system. In 77 of 84 patients (91.7 %), phase III showed equal image quality after a 50 % reduction in the X-ray dose. In 3 cases (3.6 %) the image quality and the level of contrast were better. No unified statement could be made for 4 patients (4.7 %). CONCLUSION: Digital imaging of skeletal disorders using the novel flat panel detector makes it possible to reduce the X-ray dose by 50 % with equal or even better image quality.

Adult↗

PubMed2006

Successful treatment of disseminated mucormycosis with a combination of liposomal amphotericin B and posaconazole in a patient with acute myeloid leukaemia.

The combination of resection of infected tissue and antifungal therapy is the treatment of choice in mucormycosis. In disseminated mucormycosis, where surgery is impossible, the mortality is almost 90%. We report the first case of disseminated mucormycosis that was cured with a combination therapy of liposomal amphotericin B and posaconazole without surgical intervention.

Amphotericin B↗

PubMed2006

A randomized, open-label study to compare the effects of two different doses of recombinant human growth hormone on fat reduction and fasting metabolic parameters in HIV-1-infected patients with lipodystrophy.

BACKGROUND: Several studies have shown beneficial effects of recombinant human growth hormone (r-hGH) in reducing visceral adipose tissue (VAT) in HIV-1-infected patients with lipodystrophy. METHODS: Patients were randomized to r-hGH 4 mg daily (group A) or three times per week (group B) over 12 weeks, followed by a 2 mg daily maintenance dose for 12 weeks. Magnetic resonance imaging (MRI) scans were performed to assess body composition. RESULTS: A total of 26 subjects were included in the study. VAT was reduced overall by 35.1 cm(2) (29.5%) at week 12 and by 49 cm(2) (39.9%) at week 24, respectively, compared with baseline (P<0.001 for both comparisons). By week 12, VAT was reduced by 27 and 29% (A vs B; P=0.47) while facial fat was reduced by 3.3 and 2.6 cm(2) in groups A and B, respectively (P=0.96). Over 24 weeks, VAT was reduced by 42 and 38% (P=0.35) and facial fat by 3.2 and 2.4 cm(2) in groups A and B, respectively (P=0.91), compared with baseline. There was a greater increase in high-density lipoprotein (HDL) in group A than in group B (4.9 vs 2.4 mg/dL in week 12 and 7.1 vs -0.4 mg/dL in week 24; P=0.03). Fasting insulin levels increased, whereas glucose and insulin measured in oral glucose tolerance tests remained unchanged. Drug-related side effects were transient and reversible, but more common in group A (67%) than in group B (29%). CONCLUSIONS: This study confirms reports that r-hGH effectively reduces VAT, with a relatively small reduction of facial and limb fat.

Adipose Tissue↗

PubMed2005

The Protease Inhibitor Transfer Study (PROTRA 1): abacavir and efavirenz in combination as a substitute for a protease inhibitor in heavily pretreated HIV-1-infected patients with undetectable plasma viral load.

OBJECTIVES: The aim of the study was to evaluate the safety and efficacy of abacavir (ABC) and efavirenz (EFV) instead of a protease inhibitor (PI) in HIV-1-infected subjects treated with two nucleoside reverse transcriptase inhibitors (NRTIs) and one PI with undetectable viral loads (< 50 HIV -1 RNA copies/mL). To be eligible for inclusion, patients had to have a history of viral load < 400 copies/mL for at least 3 months and had to be naive to treatment with nonnucleoside reverse transcriptase inhibitors (NNRTIs) and ABC, but multiple pretreatment and treatment failure were allowed. DESIGN: An open-label, single-centre pilot study of duration 48 weeks was conducted. ABC was added to the original treatment with two NRTIs and one PI at baseline, and at week 6 the PI was replaced by EFV. At each study visit, CD4 cell count, viral load [measured by polymerase chain reaction (PCR)] and clinical chemistry were measured. Fasting blood samples were taken at baseline and at weeks 12, 24, 36 and 48 to measure levels of cholesterol [high-density lipoprotein (HDL)/low-density lipoprotein (LDL)], triglycerides, insulin and C-peptide. Additionally, an oral glucose tolerance test (OGTT) was performed. A bioelectric impedance analysis (BIA) and a single slice abdominal and mid-thigh computed tomography (CT) scan were carried out to assess changes in body composition. RESULTS: Thirty patients were included in the study. Three patients experienced ABC-hypersensitivity and one patient demonstrated virological failure caused by nonadherence. At week 48, all remaining patients had viral loads < 50 copies/mL with stable CD4 counts. The fasting metabolic parameters and abdominal fat distribution remained unchanged. CONCLUSIONS: In heavily pretreated patients, ABC and EFV in combination provide an effective, simplified and well-tolerated alternative to PI treatment.

Adult↗

PubMed2004

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.

Adult↗

PubMed2004

[Lymphangioleiomyomatosis (LAM): a rare cause of ascites and pleural effusion].

HISTORY AND CLINICAL FINDINGS: A 45 year old woman presented at our hospital for further evaluation of intermittent abdominal pain. The patient reported that she had suffered a spontaneous pneumothorax 8 years and a pleural effusion 3 years before. DIAGNOSTIC FINDINGS AND THERAPY: Abdominal ultrasound showed abdominal fluid which proved to be chylous ascites by diagnostic paracentesis. Radiologic (lymphangiography) findings were consistent with lymphangioleiomyomatosis (LAM). Remarkably, lymphangiography resulted in an immediate disappearance of the ascitic fluid. CONCLUSION: This report depicts a case of LAM which involved both pulmonary and intestinal symptoms. Previous pulmonary problems gave a hint towards the right diagnosis. Though lymphangiography is rarely performed in these days, the method was both diagnostic and therapeutic in the case presented.

Contrast Media↗

PubMed2004

[Uterine adenomyosis in infertile patients: MR imaging findings and clinical conclusions].

PURPOSE: To evaluate the clinical value of magnetic resonance imaging (MRI) of the uterus and the pelvis in infertile female with symptomatic endometriosis for the assessment of uterine morphology and function. MATERIALS AND METHODS: Forty-one infertile women (mean age: 33.2 years) with symptomatic endometriosis documented by laparoscopy were evaluated with high-field MRI (Sonata, Siemens) using T2- and T1-weighted sequences. In addition, the patients underwent hysterosalpingoscintigraphy (HSSG) for evaluation of the uterotubal transport capacity. Pathologic findings of the uterine junction zone were correlated with the laparoscopic results, clinical symptoms and uterotubal transport capacity. RESULTS: Adenomyosis was diagnosed on T2-weigthed MR-images in 35 (85.4 %) patients (focal adenomatosis in 26 patients and diffuse adenomatosis in 9). Patients showing signs of adenomyosis tended to be older than patients without adenomyosis (mean age 34.1 years vs. 30.1 years) and showed a longer history of symptomatic endometriosis. A positive transport capacity in HSSG was observed in 73.1 % (19/26) of the patients with focal adenomyosis and in only 22.2 % (2/9) of patients with diffuse adenomyosis. In 83.3 % (5/6) of the patients without signs of adenomyosis, a positive uterotubal transport was documented. CONCLUSION: MRI of the uterus is a helpful diagnostic tool for the diagnosis of adenomyosis and for planning further therapies. Patients with the diagnosis of adenomyosis showed a reduced uterotubal transport capacity that depended on the severity of adenomyotic changes and might be a possible cause of infertility.

Adult↗

PubMed2004

[Thoracic aortic stenting: indications and results].

AIM: Determination of the conditions for good acute and long term results of interventional therapy of lesions of the thoracic aorta using stent-grafts. PATIENTS, MATERIAL AND METHODS: 51 patients with aneurysm of the thoracic aorta (type B dissections) covered rupture and aortobronchial fistula were evaluated. All cases were discussed in an interdisciplinary conference consisting of thoracic surgeon and interventional radiologist. Primarily, 20 patients were operated and 31 were treated by intervention. For all a multidetector row CT angiography was ordered prior to the discussion. All procedures were performed in a DSA suite under general anaesthesia. In 29 patients Talent LPS trade mark tube grafts and in four patients an Excluder trade mark graft was implanted. RESULTS: 29 patients had an aneurysm of the thoracic aorta, 21 a type B dissection, 19 a perforation and one patient had an aortobronchial fistula. The follow up was 13.4 months. In 29 patients the stent-graft implantation was successful, in 2 patients stent-graft delivery failed due to severe calcification and kincking of both common iliac arteries. One patient had an iliacal dissection after stent-graft delivery which was treated successfully by surgery. In two patients CT angiographic control detected endoleaks, which were treated with a second stent-graft placement. One patient with an acute perforation of the descending aorta died due to cardiac failure prior to stent-graft implantation. Any neurological complication did not occur. CONCLUSION: Percutaneous treatment of lesions of the descending thoracic aorta using stent-grafts is a safe and feasible alternative treatment to surgical repair. Prior to the a multidetector row CT angiography is necessary for exact planning of the endo-luminal treatment.

Aged↗

PubMed2003

[Early detection of colorectal tumors: CT or MRI?].

Cancer screening is currently offered for the organs breast, prostate, cervix and colorectum. With progressing technique in computerized tomography (CT) and magnetic resonance imaging (MRI) the colorectum can be increasingly better assessed. Because in CT and MRI also other organs are imaged with the colorectum, a colorectal screening automatically becomes a multiorgan screening. CT and MRI protocols designed for early detection of colorectal tumors are presented and discussed with regard to monoorganscreening (in CT: low dose, no i.v. contrast) and multiorganscreening (in CT: diagnostic dose for neighboured organs with i.v. contrast). More information under http://www.multiorganscreening.org.

Colonic Polyps↗

PubMed2003

[Diagnosis of colorectal tumors].

With the introduction of multislice CT extensive volumetric data sets can be quickly acquired in high spatial resolution. The high spatial resolution reduces partial volume effects and enables multiplanar reconstructions. Regarding the colorectum this means that the colon can be assessed if the colon is sufficiently cleaned and distended, and that transmural infiltration of colorectal carcinoma and liver metastases can be better detected. T-staging of colon cancer is less important than T-staging of rectal cancer. Based on the higher contrast MRI is superior to CT in T-staging of rectal cancer and in the differentiation between scarring tissue and recurrence of carcinoma.

Colon↗

PubMed2003

[Importance of coloncontrast enema].

Screening for colorectal cancer starts with digital exploration of the rectum and was extended in 1977 using the haemoccult test. It was referred to detect 24% of malignancies, but with a high number of false positive findings. Combination of regular follow up examinations and coloscopy reached a sensitivity of 80%. International studies demonstrated the need of a complete colon examination, so that the coloscopy is actually an important screening method in Germany. The coloncontrast examination is a safe, cost-effective method with a low complication rate. It is suitable especially for patients, in which the colonoscopic evaluation of the colon was not complete and provides additional morphological informations in many cases.

Adenomatous Polyps↗

PubMed2003

[The role of stereotactic 11G vacuum biopsy for clarification of BI-RADS IV findings in mammography].

PURPOSE: To evaluate the potential of stereotactic vacuum breast biopsy in the histologic evaluation of suspicious mammographic findings ( BI-RADS IV). MATERIALS AND METHODS: In 221 patients with 227 probable mammographic lesions categorized as ( BI-RADS -IV), stereotactic biopsies were performed with an 11-gauge vacuum-assisted biopsy device (Mammotome). The evaluation included the histology of the specimens obtained with the Mammotome or with surgery, the time for the biopsy, the amount of bleeding, number of rotations and procured specimens, the extent of the resection and the complications. RESULTS: The biopsies were technically successful in 214 of the 227 probable mammographic lesions, with 176 lesions mostly resected and 34 lesions removed more than 50 %. No representative tissue was obtained from 4 lesions. All biopsies were performed without any clinically relevant complications and terminated after adequate material was obtained (O 28 specimens, 2.58 rotations). The mean time needed for performing the biopsy was 40.2 minutes. The histologic findings were DCIS (42 lesions), ADH (7 lesions), LCIS (3 lesions), ID-Ca (14 lesions, IL-Ca (3 lesions), and IDL-Ca (1 lesion). In 28 of 42 lesions with the initial DCIS histology, the surgical histology was also DCIS (n=28) or no residual tumor (n=10). In 4 lesions with an initial DCIS-histology, the surgical histology was invasive ductal cancer (9.5 %). The late follow-up examinations (up to 3 years) did not find any evidence of a false negative biopsy. CONCLUSION: Stereotactic vacuum breast biopsy ideally complements existing breast biopsy methods. The method is minimal invasive with a low rate of mostly minor complications.

Artifacts↗

PubMed2003

[MR-guided biopsies of undetermined liver lesions: technique and results].

PURPOSE: To evaluate safety and precision of liver tumor biopsies performed in an open low field system using different sequence techniques. MATERIALS AND METHODS: In 47 patients with liver tumors, MR-guided biopsies were performed in a low field system (0.2 Tesla, Magnetom Open, Siemens) using two different sequences. The procedure was monitored with T1-weighted FLASH sequences (TR/TE = 100/9; 70(3)) in all patients and with FISP-Rotated-Keyhole-sequence (TR/TE = 18/8; 90(3)) in additional 20 patients. After positioning of the needle tip in the tumors, 166 biopsy specimens were acquired with 16 G cutting needles (Somatex*). The diameter of the biopsied lesions ranged from 1 to 10 cm (mean diameter 3.2 cm). Visibility of the needles and precision of the biopsies were evaluated. RESULTS: All interventional biopsies were performed without vascular or organ injuries. Adequate specimens for histologic interpretation were obtained in 42 cases (89.3%). The biopsy results were non-specific in 2 patients (4.2%) and the lesions missed in 3 patients (6.3%). Mean in-room time was 35 minutes and the intervention time was 8.3 minutes. T1-weighted FLASH images proved optimal for confirming needle-tip placement during the biopsies or punctures. Organs, tumors and vessels were easily identified. The FISP sequence proved to be inferior in visualizing vessels and tumors. CONCLUSION: MR-guided liver biopsies are safely and precisely performed using T1-weighted FLASH-sequences with sufficient visualization of the lesions and might be complementary to US- or CT-guided biopsies.

Adult↗