Biomedical subjects

Dirk Lindner

Publications and source records attributed to Dirk Lindner.

7 recordsLinked to original sources

PubMed2005

[The reliability of stereotaxy in diagnosis of intracranial space occupying lesions].

A total of 79 patients with a suspect space occupying intracranial lesion was operated stereotactically. After CT and MR image acquisition, entry and target coordinates were defined and biopsy trajectories were simulated preoperatively using a special planning software. Biopsy specimens allowed a satisfactory neuropathological examination and diagnostic result in 74 of 79 (93.7%) cases. In the remaining 5 of 79 (6.3%) patients, a glioses was diagnosed in three cases; in only two patients could no pathological process be proved. 10 of 79 (12.7%) patients showed an intraoperative bleeding out of the biopsy-cannula during serial stereotaxy, which was associated with a CT-detectable hematoma up to 7 mm in diameter in only three cases (3.8%). In no patient was the detection of intracerebral bleeding the reason for any neurological deficit. In summary, the high percentage of satisfactory neuropathological diagnoses, the low rate of stereotaxy-associated morbidity and the comfortable and safe use of computer and stereotactic devices justify this kind of minimally invasive diagnostic measure as a routine method.

Adolescent↗

PubMed2004

[Investigation of antioxidant therapy with sodium selenite in acute pancreatitis. A prospective randomized blind trial].

BACKGROUND AND PURPOSE: Oxygen free radicals appear in the early phase of acute pancreatitis followed by an imbalance between the oxygen and anti-oxygen system. Sodium selenite may play an important role in the reduction of radicals in experimental pancreatitis. The aim of this study was to evaluate the effects of selenium in a clinical prospective trial. PATIENTS AND METHODS: 70 patients with acute pancreatitis were prospectively allocated to a selenium and a placebo group. Clinical and paraclinical parameters were investigated with a follow-up of 90 days after hospital stay. RESULTS: The clinical course of the two treatment groups did not show statistically significant differences. Five patients in the selenium and three patients in the placebo group died. Depending on selenium therapy, antioxidant substances were presented in higher levels. All 17 clinical parameters showed no statistical significance. CONCLUSION: Substitution of sodium selenite has no beneficial effect on the clinical outcome of patients with acute pancreatitis.

Acute Disease↗

PubMed2004

Unusual penetrating cranio-orbital injury by a cut-off wheel.

The rare case of a penetrating cranio-orbital injury and the surgical treatment is presented. A 38-year-old woman was brought to the Emergency Unit of the University of Leipzig Hospital after suffering a severe craniocerebral injury from a broken cut-off wheel. A computed tomography (CT) scan demonstrated the entrance of the cut-off wheel with extension from the left sinus maxillaris and frontalis through the median part of the left-sided orbit to the anterior skull base. After removing the cut-off wheel and metal splinters, the neurosurgeon performed an osteoplastic bifrontobasal trepanation with revision of the wound channel. Three years later, the patient has no neurological deficit and the CT scan shows a small hypodensity behind the sinus frontalis on the left side.

Accidents, Occupational↗

PubMed2004

NEUROGATE: a new MR-compatible device for realizing minimally invasive treatment of intracerebral tumors.

The authors report on the handling and the practicability of a newly developed MR-compatible device, the NEUROGATE (Daum GmbH, Germany), which allows precise planning, simulation and control of stereotactic biopsy in patients with suspect intracranial lesions, and which allows minimally invasive maneuvers to be performed in a comfortable way. Twenty-eight patients were examined stereotactically in the Signa SP interventional 0.5 Tesla MRI (General Electric Medical Systems, USA), including 15 patients with malignant intracerebral tumors and poor general medical conditions (8 gliomas, 7 metastases) who were treated by laser-induced interstitial thermotherapy (LITT) after definite intraoperative neuropathological diagnosis. As a special stereotactic holding device, the NEUROGATE was favored as a reliable tool for stereotaxy and minimally invasive procedures.

Adult↗

PubMed2004

Quantitative assessment of parenchymal and ventricular readjustment to intracranial pressure relief.

A 26-year-old patient underwent endoscopic third ventriculostomy for the treatment of obstructive hydrocephalus. 3D volume data sets were obtained at 3 T before surgery and three times after surgery. Off-line analysis of individual imaging data (initial linear registration, intensity adjustment, and final nonlinear registration of pre- to postoperative MR images) yielded 3D displacement fields representing the postoperative structural brain change. In principle, such an analysis technique can be used in any clinical follow-up for which careful observation of tissue readjustment is of particular importance.

Adult↗

PubMed2003

Investigation of time-dependency of intracranial brain shift and its relation to the extent of tumor removal using intra-operative MRI.

The object of the paper is to investigate intra-operative brainshift and its relation to the extent of tumor removal. Repeated T1w 3D datasets were acquired at different time points intra-operatively (T0; T1; T2...Tx) using a vertical open 0.5T MR scanner in six patients with intracranial tumor. An offline analysis with initial linear registration, intensity adjustment and finally nonlinear registration of the first versus subsequent time points (T0/T1; T0/T2...To/Tx) was performed, yielding a 3D displacement vector field that describes the brainshift. Brainshift was analysed qualitatively and quantitatively. A semi-automatic segmentation technique was used for calculation of the tumor size and the size of tumor remnants. Semi-automatic segmentation was reliable in all but two cases. Segmentation was difficult and unreliable in astrocytomas grade II. The shift basically followed gravity. The major shift reached levels up to 25 mm. Significant shift was observed at the first time point (T0). Intra-operative brainshift can be analysed qualitatively and also captured quantitatively. Neuronavigation that is based on pre-operatively acquired datasets is associated with a significant risk of surgical morbidity at a very early time point. Parallelisation on a workstation cluster may reduce computation time so that information about the displacement can facilitate updated navigation.

Adult↗

PubMed2002

Iterative neuronavigation using 3D ultrasound. A feasibility study.

Intra-operative ultrasound (iUS) can generate 2D images in real-time as well as near real-time 3D datasets of the current situation during an intervention. Tracked ultrasound can locate the images in 3D space and relate them to patient, devices, andpre-operative planning data. Therefore, tracked US is an efficient means for controlling the validity of pre-operative planning, recognition of changes (brain shift) during the intervention, replanning of the operational path due to situational changes (iterative navigation), and finally, controlling the results (residual tumor). This paper describes a neuronavigation system exploiting this potential of interventional tracked US for permanent control of intervention progress and iterative adaptation of the planned procedure to the current situation.

Brain Mapping↗