Search Results

You are looking at 1 - 10 of 78 items for :

  • "Evans index" x
Clear All
Restricted access

Intracranial volume-pressure relationship in man

Part 2: Clinical significance of the pressure-volume index

Joseph Th. J. Tans and Dick C. J. Poortvliet

of 15.2 ± 4.56 ml when only B-waves were absent. The highest mean PVI (16.5 ± 5.21 ml) was calculated for 19 epochs featuring a Pmod of 15 mm Hg or less, a Pmax of 20 mm Hg or less, and no A- or B-waves; in other words a normal VFP recording. Yet the PVI was less than 18 ml in 63% and less than 13 ml in 37% of these epochs, demonstrating that compliance may be low even if VFP is completely normal for 24 hours. TABLE 2 Mean PVI at different values of Pmod, Pmax, and Evans index with or without pressure waves * Parameters No. of Epochs

Restricted access

Yuichiro Tanaka, Keizo Sakamoto, Shigeaki Kobayashi, Norio Kobayashi and Shinsuke Muraoka

of the CSF pathway in the posterior fossa. The CT scans were obtained 1 to 3 hours after intrathecal administration of the contrast medium by lumbar tap in an attempt to identify any obstruction ( Fig. 5 ). Fig. 3. Graph showing changes in ventriclar size in each of the five cases with a biphasic pattern of ventricular dilatation. Ventricular size is expressed according to the Evans index obtained from computerized tomography (CT) scanning. A ventriculoperitoneal shunt was placed in Case 4 at the time of maximum enlargement of the ventricles. Max = maximum

Restricted access

Joseph T. J. Tans and Dick C. J. Poortvliet

present study was undertaken to verify whether indeed a relationship exists between R csf and compliance in a larger, heterogeneous group of adult hydrocephalus patients. Clinical Material and Methods This series comprised 114 consecutive patients with hydrocephalus who were considered to be possible candidates for shunt placement. Hydrocephalus was defined as an Evans index of greater than 0.30 on computerized tomography scans. All patients investigated had shown signs or symptoms for at least 3 months. Patients with space-occupying lesions were excluded. The

Restricted access

Catherine J. De Vile, David B. Grant, Brian E. Kendall, Brian G. R. Neville, Richard Stanhope, Kate E. Watkins and Richard D. Hayward

, unilateral frontal, bilateral frontal, unilateral temporal, bilateral temporal, and posterior fossa involvement. “Tumor components”: The proportion of solid and cystic components was assessed for the entire tumor as well as for any tumor within the hypothalamic region. “Hydrocephalus” was graded as mild (1), moderate (2), moderately severe (3), or severe (4) using the Evans' Index (maximal width of the frontal horns/maximal width of the inner skull × 100%) for assessment of ventricular size ( Table 1 ). TABLE 1 Characteristics of patients with childhood

Restricted access

Agnita J. W. Boon, Joseph T. J. Tans, Ernst J. Delwel, Saskia M. Egeler-Peerdeman, Patrick W. Hanlo, Hans A. L. Wurzer, Cees J. J. Avezaat, Dirk A. de Jong, Rob H. J. M. Gooskens and Jo Hermans

developed gait disturbance of both legs, unexplained by other conditions, and a gait scale score of at least 12; 2) a mild-to-moderate cognitive deficit without aphasia, emerging with or after the gait disturbance, and a dementia scale score of at least 12; 3) a disability mRS grade of at least 2; and 4) a computerized tomography (CT) scan showing a communicating hydrocephalus with an Evans' index of 0.3 or greater and a ventricular index greater than 0.8, 4 without clinically relevant parenchymal lesions, the sum of the four largest sulci at the convexity being less

Restricted access

Agnita J. W. Boon, Joseph T. J. Tans, Ernst J. Delwel, Saskia M. Egeler-Peerdeman, Patrick W. Hanlo, Hans A. L. Wurzer, Cees J. J. Avezaat, Dirk A. de Jong, Rob H. J. M. Gooskens and Jo Hermans

). Eligibility Criteria Between September 1990 and July 1995 101 patients with NPH were enrolled in the study because they fulfilled the following inclusion criteria: 1) a gradually developed gait disturbance in both legs, unexplained by other conditions, and a gait scale score of at least 12; 2) a mild-to-moderate cognitive deficit without aphasia, emerging with or after the gait disturbance, and a dementia scale score of at least 12; 3) a disability mRS grade of at least 2; and 4) a computerized tomography (CT) scan showing communicating hydrocephalus with an Evans' index

Restricted access

Agnita J. W. Boon, Joseph T. J. Tans, Ernst J. Delwel, Saskia M. Egeler-Peerdeman, Patrick W. Hanlo, Hans A. L. Wurzer and Jo Hermans

developing gait disturbance of both legs that was unexplained by other conditions and a gait scale score of at least 12; 2) a mild-to-moderate cognitive deficit without aphasia emerging together with or after the gait disturbance and a dementia scale score of at least 12; 3) a handicap mRS score of at least 2; and 4) a CT scan demonstrating a communicating hydrocephalus with an Evans' index of 0.3 or more and a ventricular index greater than 0.8, 4 without clinically relevant parenchymal lesions, the sum of the four largest convexity sulci being less than 25 mm (real size

Restricted access

Julio Sotelo, Mario Izurieta and Nicasio Arriada

-up neuroimaging studies were obtained the day after the shunt procedure and repeated approximately every 3 months; the Evans index, as the ratio of frontal horn distance to maximal biparietal diameter (normal 0.30 ± 3), 24 was measured in each subsequent study. The possibility of shunt dysfunction was considered when surgical revision was necessary, either for shunt removal or for flow restoration. Statistical comparisons were made using the Student t-test for independent values. Open VP Shunt The hydrokinetic performance of the open VP shunt relies on the peritoneal

Restricted access

Jose F. Alén, Alfonso Lagares, Ramiro D. Lobato, Pedro A. Gómez, Juan J. Rivas and Ana Ramos

. 6 The amount of IVH was classified as none, small, moderate, and diffuse. Hydrocephalus was recorded as present when the Evans index, that is, the ratio of the largest width of the frontal horns to the maximal biparietal diameter, was greater than 30%. To determine whether a nonaneurysmal pattern of bleeding could be distinguished from an apparently similar aneurysmal one on early CT scans, the initial unenhanced scans were evaluated by an experienced neuroradiologist in a blinded fashion and classified as showing a perimesencephalic or a nonperimesencephalic

Restricted access

Ullrich Meier and Sven Mutze

disturbed and ICP increases further, the valve's high-pressure chamber opens. This keeps ICP within the physiological range even when the patient is in the upright position, thereby systematically avoiding either an overdrainage or an acute rise in ICP ( Fig. 1 ). Computerized tomography studies were obtained in all 80 patients preoperatively and 1 year postoperatively. During all 160 of these CT scanning sessions, ventricular volume in the frontal horn was ascertained using the Evans Index; any postoperative changes were measured in accordance with this index as well