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W R Lanksch

Publications and source records attributed to W R Lanksch.

67 records · Page 4Linked to original sources
PubMed1994

[Cerebral aneurysms: their 3-dimensional imaging with spiral CT].

In this study, the possibility of non-invasive, three-dimensional demonstration of aneurysms of the basal cerebral arteries by means of spiral CT was investigated. The first step was to obtain exact definition of optimal examination parameters. Angio CTs at appropriate levels were performed on 10 subjects and time/density curves of the arterial and venous phases obtained in order to optimise the beginning of the arterial spiral CT series. The second step in this investigation was to examine 7 patients; in 6 of these basal aneurysms had been demonstrated by DSA. By means of multiplanar three-dimensional reconstruction from the data of the spiral CT it was possible to demonstrate 7 aneurysms with a diameter between 5 and 18 mm. Their position and relationship to the bony skull was also shown.

Adult↗
PubMed1994

[Cerebral arteriovenous angiomas: 3-dimensional demonstration by spiral CT].

In 20 patients with known or suspected supratentorial arteriovenous malformations, an attempt was made to see how far CT angiography with 3-dimensional reconstructions is able to make a diagnosis and to differentiate the various components of the angioma. Spiral CT was performed following an intravenous bolus injection of 60-80 ml of iodine containing contrast medium. In all patients the diagnosis was confirmed by intra-arterial DSA of the vertebral vessels. In 13 patients, av malformations could be diagnosed following multiplanar 3-D reconstructions which agreed with the findings on DSA. The large supplying vessels, the nidus and the large draining veins could be defined with certainty. In 6 patients follow-up examination after embolisation was performed. The results could be demonstrated in three dimensions and the success of treatment could be documented unequivocally. CT angiography with 3-D reconstruction is able to supply important information in the majority of intracranial av malformations, both during initial investigation and following treatment.

Adolescent↗
PubMed1994

Hyperostosis in meningiomas: MR findings in patients with recurrent meningioma of the sphenoid wings.

PURPOSE: We used MR imaging to analyze retrospectively the pattern of hyperostosis occurring concomitantly with recurrent sphenoid wing meningiomas. METHODS: Bone involvement was compared in 12 corresponding CT and MR studies of 10 female patients with sphenoid wing meningiomas recurrence after earlier surgical treatment. Four of these had histologically confirmed meningiomatous infiltration of the bone. RESULTS: All patients had CT findings of localized hyperostosis of parts of the sphenoid wings. MR revealed inhomogeneous areas of slightly increased signal intensity in hyperostotic bone on T2-, proton density- and T1-weighted sequences. In nine of 10 patients, segments of the hyperostotic bone showed different degrees of gadolinium enhancement. CONCLUSIONS: Because earlier studies have revealed high incidences of meningiomatous bone infiltration in sphenoid wing meningiomas, and because infiltration was confirmed in four of our patients, we postulate that the gadolinium enhancement in the area of hyperostosis may be related to meningiomatous bone infiltration.

Adult↗
PubMed1993

Monitoring of jugular venous oxygen saturation in comatose patients with subarachnoid haemorrhage and intracerebral haematomas.

To prevent secondary cerebral ischemia in comatose patients it would be of great importance to assess cerebral blood flow. Recently monitoring of the jugular venous oxygen saturation (SJVO2) has been shown to continuously evaluate cerebral oxygenation and to estimate cerebral blood flow. While most of these studies have dealt with severely head injured patients, we investigated cerebral oxygenation in 50 comatose patients due to an intracerebral haematoma (n = 14), subarachnoid haemorrhage (n = 12) and severe head injury (n = 24). In these groups of patients, the reaction of SJVO2 to hyperventilation and to lowering of blood pressure was studied. Moderate hyperventilation from 35 to 28 mmHg resulted in a significant decrease of SJVO2 in all groups. A critical SJVO2 between 50 and 55% was found in one half of the patients studied, a pathological SJVO2 below 50% was seen in 23% of the cases. Lowering of arterial blood pressure within the limits of autoregulation resulted in decreases of SJVO2 in patients with intracerebral haematomas only. 55% of these patients showed signs of insufficient cerebral oxygenation. Furthermore the frequency of spontaneous desaturation episodes was studied retrospectively and comparison made between the different groups. These episodes were found more frequently in patients with intracerebral haematomas compared to patients with severe head injury. In conclusion, monitoring of jugular venous oxygen saturation is a valuable tool for detecting and treating insufficient cerebral oxygenation in comatose patients following intracerebral haemorrhage, subarachnoid haemorrhage and severe head injury.

Adolescent↗
PubMed1993

Influence of body position on jugular venous oxygen saturation, intracranial pressure and cerebral perfusion pressure.

Elevation of the head as a common practice to reduce raised intracranial pressure (ICP) has been discussed controversially of late. Some investigators were able to show that besides lowering ICP head elevation may also reduce cerebral perfusion pressure (CPP). For a new evaluation of optimal head position in neurosurgical care it would be of importance to know the influence of body position on cerebral perfusion. We therefore employed continuous jugular venous oximetry, monitoring cerebral oxygenation, to study the effect of 0 degrees, 15 degrees, 30 degrees, and 45 degrees head elevation on ICP, CPP and jugular venous oxygen saturation (SJVO2) in 25 comatose patients with reduced intracranial compliance. As expected, head elevation significantly reduced ICP from 19.8 +/- 1.3 mmHg at 0 degrees to 10.2 +/- 1.2 mmHg at 45 degrees. Already at 30 degrees 92% of the possible effect on ICP was detected. There was no statistically significant change in CPP and SJVO2 associated with varying head position. Individual reactions of CPP to changes in head position, however, were quite unpredictable. The data suggest that an individual approach to head elevation is to be preferred. A moderate head elevation between 15 degrees and 30 degrees significantly reduces ICP and, in general, does not impair cerebral perfusion. Jugular venous oximetry may be used to optimize ICP, CPP and cerebral oxygenation.

Adult↗
PubMed1993

[MRT in cervical disk herniation: plain vs. contrast-enhanced images].

Aim of this study was to assess the value of Gd-DTPA administration in MRI of cervical disk herniations. In 34 patients, showing 40 cervical disk herniations, plain proton density- and T1-weighted as well as contrast-enhanced T1-weighted 2D-FLASH images were generated. Contrast between the herniated material and the CSF already was sufficient without administration of Gd-DTPA in all cases. Sufficient contrast between the herniations and the intraforaminal structures was obtained in 13/40 cases and 40/40 cases on plain and contrast-enhanced images, respectively. Definition of the herniated disks was judged to be sufficient in 30/40 cases on plain images and 40/40 cases on contrast-enhanced images. The diagnostic value of the images was improved in 3/12 lateral and 7/8 intraforaminal herniations by contrast administration, whereas there was no significant increase in diagnostic value in posterior or posterolateral herniations. As a result, Gd-DTPA administration is recommended if definition of lateral and intraforaminal disk herniations in MRI is poor.

Adult↗
PubMed1992

["Surgical projection" in the gadolinium-DTPA (Gd-DTPA)-supported NMR tomographic diagnosis of lateral lumbar disk prolapse].

In a group of 25 patients the coronal views of plain and Gd-DTPA-enhanced MRI studies were correlated with CT and operative findings. All series included sagittal, transverse and coronal FLASH sequences (GE 500/6, flip angle 70 degrees), sagittal proton density-(SE 2500/15) and T2-(SE 2500/70) weighted images. MR diagnosis proved to be correct in all cases. Compared to CT and axial MRI herniated disk material in the lateral intravertebral space and its relationship to nerve roots was demonstrated more clearly on coronal views.

Adult↗
PubMed1991

[A 3-dimensional reconstructive procedure in lumbar computed tomography].

In this study, 50 patients were examined by a Siemens' "Somatom Plus"; continuous 2 mm sections between the third lumbar and first sacral vertebra were obtained. The accuracy of the 3-D reconstruction software programme was checked by measuring a polyethylene phantom of a second lumbar vertebra. Reconstruction was carried out with a threshold definition of 150 Hu. In each case, four standard projections and medio-sagittal, medio-lateral and coronary sections were reconstructed, photographed and compared with axial CT sections and conventional radiographs. All these imaging procedures were suitable for the diagnosis of osteochondrosis and chondrosis. Spondylosis was diagnosed more frequently on 3-D CT. Spondylarthrosis, with narrowing of the intervertebral foramina and root canals is shown particularly well by 3-D CT, since the entire extent of these structures can be seen. 3-D surface reconstruction of the lumbar spine is useful in the diagnosis of lumbar spondylarthrosis with narrowing of the root canals and of the spinal canal. This method of axial Ct is superior to conventional radiography of the lumbar spine in the usual two planes.

Adult↗
PubMed1990

[MRI of the cervical spine using T1-weighted multislice FLASH sequences].

A study has been carried out to evaluate contrast and image quality of cervical structures using multislice 2D-flash sequences with long repetition times (TR = 400 ms.) and short echo delay times (TE = 5.8 ms.). The examinations were carried out using ten normals with an MRI of 1.5 Tesla and flip angles of 10, 20, 30, 50, 70 and 90 degrees. The best contrast between intervertebral disc and surrounding tissue was obtained between 50 and 70 degrees, best contrast between compact bone and CSF with 10 degrees. In order to demonstrate degenerative changes of the cervical spine, it appears sensible to use a combination of these angles. The described sequences produce good images of the cervical structures with little image degradation. Compared to T1-weighted spin-echo sequences, the method has a number of significant advantages, such as variations in image contrast, higher maximal number of slices, contiguous imaging and less imaging time.

Adult↗
PubMed1987

[Diagnosis and surgical treatment of cervical intervertebral disk displacement and cervical myelopathy].

Despite the availability of excellent neuroradiological examination techniques, a decision to operate is usually still reached largely on the basis of a diagnosis of radical and/or medullary cervical compression syndrome made by clinical neurological examination. Computer tomography has allowed a decisive improvement in the diagnosis of these processes, since the position of parts of discs that have prolapsed or sequestrated dorsally or dorsolaterally relative to the spinal cord and the nerve roots can be visualized directly. Since core spin tomography does not yield information that is any more helpful in the diagnosis, despite the considerably higher level of technical sophistication and higher costs, we are of the opinion that there is no call to apply this procedure routinely for the diagnosis of medial and lateral cervical disc rupture. Since the neurological symptoms do not always allow localization of the radicular or medullary damage to the segment or segments affected, it is sometimes necessary to perform myelography with water-soluble contrast media for this purpose. The microsurgical procedures available are restricted foraminotomy for the relief of cervical nerve root compression and ventral diskectomy for the relief of spinal cord compression.

Adult↗
PubMedDate not supplied

Carpal tunnel syndrome: staging of median nerve compression by MR imaging.

The purpose of this prospective study was to determine the potential of MR imaging to depict morphologic alterations of the median nerve correlating with the stage of carpal tunnel syndrome (CTS). Eighteen wrists of normal subjects and 81 wrists of patients with CTS were examined. MR imaging was performed with proton-density- and T2-weighted spin-echo sequences. Staging of CTS was done on the basis of clinical and electrophysiological testing, including evaluation of the number of previous steroid infiltrations in conservative treatment. Median nerve flattening, cross-sectional area, and signal intensity were measured from the distal radius to the end of the carpal tunnel. Delineation and structure of the median nerve were recorded qualitatively by two experienced radiologists in consensus. Three major MR imaging criteria of early CTS were (a) isolated prestenotic and intracarpal swelling of the median nerve (P < .01), (b) the absence of significant flattening, and (c) a generalized increase in signal intensity retrograde to the distal radius (P < .01). The nerve showed sharply delineated contours and a homogeneous signal pattern. Advanced CTS was characterized by retrograde swelling of the median nerve to the distal radius (P < .01) and decreased signal intensity (P < .05). Demarcation of the nerve became poorer, and its signal pattern appeared fasciculated. After steroid infiltration, the median nerve was difficult to delineate, showed an inhomogeneous structure, and swelling was less pronounced than without steroid infiltration (P < .05). MR imaging yields typical morphologic findings that correlate with the duration and severity of median nerve compression. Hence, MR imaging allows staging of median nerve compression in CTS and thus may contribute to therapeutic decision-making.

Carpal Tunnel Syndrome↗
PubMedDate not supplied

Lymphocytic hypophysitis simulating a pituitary adenoma in a nonpregnant woman.

Lymphocytic adenohypophysitis can cause pituitary expansion and hypopituitarism closely mimicking the features of a pituitary adenoma. In contrast to pituitary adenoma, lymphocytic adenohypophysitis occurs almost exclusively in young women in relation to pregnancy. We report a case of a 43-year-old nonpregnant nullipara who exhibited an intrasellar mass with diffuse homogeneous contrast enhancement on magnetic resonance imaging scanning. Serum hormone analyses revealed secondary hypoadrenalism, hypothyroidism, and hypogonadism. The patient underwent surgery for a presumed nonsecreting pituitary adenoma. Histopathological examination showed extensive infiltration of the anterior pituitary gland by chronic inflammatory cells. The immunohistochemical pattern of the inflammatory cells indicated the chronic and putatively autoimmune nature of the disease.

Adenoma↗