Effect of age on cerebral venous circulation disturbances in the rat

2000 ◽  
Vol 93 (2) ◽  
pp. 298-304 ◽  
Author(s):  
Hiroyuki Otsuka ◽  
Hiroyuki Nakase ◽  
Kiyoshi Nagata ◽  
Katsuhiro Ueda ◽  
Oliver Kempski ◽  
...  
Keyword(s):  
Venous Occlusion ◽  
Aged Rats ◽  
Venous Flow ◽  
Content Type ◽  
Young Rats ◽  
Venous Circulation ◽  
Age Related ◽  
Venous Infarct ◽  
Group A ◽  
Fine Print

Object. Mild cerebral venous circulation disturbances (CVCDs) in aged patients are frequently known to cause unexpectedly severe postoperative complications in neurosurgical practice. The object of the present study was to determine whether there are age-related differences involved in vulnerability to CVCDs.Methods. Thirty-eight male Wistar rats were used. A single cortical vein with a 100-µm diameter was occluded photochemically by using rose bengal dye and fiberoptic illumination in young (Group Y, 19 animals aged 10–14 weeks) and aged (Group A, seven animals aged 80–100 weeks) rats. Five young and seven aged animals served as sham-operated controls. Regional cerebral blood flow (rCBF) was determined from local CBF, which was measured at 25 (5 × 5) identical locations, with the occluded vein located central to the scanning field, by using a laser Doppler scanning technique every 15 minutes for 90 minutes after venous occlusion. The cerebral venous flow pattern was examined using fluorescence angiography until 90 minutes after occlusion. Histological specimens were examined 24 hours after occlusion. In Group Y, rCBF did not change significantly after venous occlusion. However, in Group A, rCBF decreased rapidly beginning 15 minutes after occlusion. Significant intergroup differences were observed 30, 60, and 90 minutes after occlusion. Venous flow arrest, which resulted in venous infarct, was observed on angiography 90 minutes after occlusion in two (10.5%) of 19 young and six (85.7%) of seven aged rats. The venous thrombus in Group A rats was significantly larger than that in Group Y rats 90 minutes after occlusion. Venous infarction was seen in all aged rats (100%) and in six young rats (31.6%); the infarct size, expressed as a percentage of the size of the ipsilateral hemisphere, was significantly larger in aged rats than in young rats.Conclusions. This study demonstrated an age-related increase in the rate and size of venous infarct following vein occlusion, suggesting that the greater vulnerability to CVCDs in the aged brain might be attributed to early and extensive hypoperfusion of circumscribed brain areas drained by the occluded vein. The larger thrombus formation in aged animals indicates that a shift in the thrombogenetic/thrombolytic equilibrium is responsible for the observed effect.

The use of intraarterial papaverine in the management of vasospasm complicating arteriovenous malformation resection

1995 ◽  
Vol 82 (2) ◽  
pp. 296-299 ◽  
Author(s):  
Michael K. Morgan ◽  
Maurice J. Day ◽  
Nicholas Little ◽  
Verity Grinnell ◽  
William Sorby
Keyword(s):  
Arteriovenous Malformation ◽  
Perfusion Pressure ◽  
Aneurysmal Subarachnoid Hemorrhage ◽  
Venous Occlusion ◽  
Neurological Deterioration ◽  
Unusual Complication ◽  
Content Type ◽  
First Case ◽  
Normal Perfusion Pressure Breakthrough ◽  
Fine Print

✓ The authors report two cases of treatment by intraarterial papaverine of cerebral vasospasm complicating the resection of an arteriovenous malformation (AVM). Both cases had successful reversal of vasospasm documented on angiography. In the first case sustained neurological improvement occurred, resulting in a normal outcome by the time of discharge. In the second case, neurological deterioration occurred with the development of cerebral edema. This complication was thought to be due to normal perfusion pressure breakthrough, on the basis of angiographic arterial vasodilation and increased cerebral blood flow. These two cases illustrate an unusual complication of surgery for AVMs and demonstrate that vasospasm (along with intracranial hemorrhage, venous occlusion, and normal perfusion pressure breakthrough) should be considered in the differential diagnosis of delayed neurological deterioration following resection of these lesions. Although intraarterial papaverine may be successful in dilating spastic arteries, it may also result in pathologically high flows following AVM resection. However, this complication has not been seen in our experience of treating aneurysmal subarachnoid hemorrhage by this technique.

Beta—tricalcium phosphate as a substitute for autograft in interbody fusion cages in the canine lumbar spine

2002 ◽  
Vol 97 (3) ◽  
pp. 350-354 ◽  
Author(s):  
Takashiro Ohyama ◽  
Yoshichika Kubo ◽  
Hiroo Iwata ◽  
Waro Taki
Keyword(s):  
Lumbar Spine ◽  
Tricalcium Phosphate ◽  
Interbody Fusion ◽  
Donor Site ◽  
Posterolateral Approach ◽  
Content Type ◽  
Spine Model ◽  
Group A ◽  
Group B ◽  
Fine Print

Object. An interbody fusion cage has been introduced for cervical anterior interbody fusion. Autogenetic bone is packed into the cage to increase the rate of union between adjacent vertebral bodies. Thus, donor site—related complications can still occur. In this study a synthetic ceramic, β—tricalcium phosphate (TCP), was examined as a substitute for autograft bone in a canine lumbar spine model. Methods. In 12 dogs L-1 to L-4 vertebrae were exposed via a posterolateral approach, and discectomy and placement of interbody fusion cages were performed at two intervertebral disc spaces. One cage was filled with autograft (Group A) and the other with TCP (Group B). The lumbar spine was excised at 16 weeks postsurgery, and biomechanical, microradiographic, and histological examinations were performed. Both the microradiographic and histological examinations revealed that fusion occurred in five (41.7%) of 12 operations performed in Group A and in six (50%) of 12 operations performed in Group B. The mean percentage of trabecular bone area in the cages was 54.6% in Group A and 53.8% in Group B. There were no significant intergroup differences in functional unit stiffness. Conclusions. Good histological and biomechanical results were obtained for TCP-filled interbody fusion cages. The results were comparable with those obtained using autograft-filled cages, suggesting that there is no need to harvest iliac bone or to use allo- or xenografts to increase the interlocking strength between the cage and vertebral bone to achieve anterior cervical interbody fusion.

Age-related changes in the proportion of intracranial cerebrospinal fluid space measured using volumetric computerized tomography scanning

2002 ◽  
Vol 97 (3) ◽  
pp. 607-610 ◽  
Author(s):  
Hiroshi Wanifuchi ◽  
Takashi Shimizu ◽  
Takashi Maruyama
Keyword(s):  
Cerebrospinal Fluid ◽  
Computerized Tomography ◽  
Ct Scanning ◽  
Volume Measurement ◽  
Intracranial Volume ◽  
Content Type ◽  
Standard Curve ◽  
Age Related ◽  
Fine Print ◽  
Age Related Changes

Object. The purpose of this study was to establish a standard curve to demonstrate normal age-related changes in the proportion of intracranial cerebrospinal fluid (CSF) space in intracranial volume (ICV) during each decade of life. Methods. Using volumetric computerized tomography (CT) scanning and computer-guided volume measurement software, ICV and cerebral parenchymal volume (CPV) for each decade of life were measured and the intracranial CSF ratio was calculated by the following formula: percentage of CSF = (ICV − CPV)/ICV × 100%. The standard curve for age-related changes in normal percentages of intracranial CSF was obtained. Conclusions. Based on this standard curve, the percentage of intracranial CSF rapidly increased after the sixth decade, seeming to reflect the brain atrophy that accompanies increased age.

Prevention of postoperative posterior tethering of spinal cord after resection of ependymoma

2003 ◽  
Vol 99 (2) ◽  
pp. 181-187 ◽  
Author(s):  
Takeo Goto ◽  
Kenji Ohata ◽  
Toshihiro Takami ◽  
Misao Nishikawa ◽  
Akimasa Nishio ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Neurological Deterioration ◽  
Fisher Exact Test ◽  
Content Type ◽  
Exact Test ◽  
Spinal Ependymoma ◽  
Group A ◽  
Delayed Neurological Deterioration ◽  
Group B ◽  
Fine Print

Object. The authors evaluated an alternative method to avoid postoperative posterior tethering of the spinal cord following resection of spinal ependymomas. Methods. Twenty-five patients with spinal ependymoma underwent surgery between 1978 and 2002. There were 16 male and nine female patients whose ages at the time of surgery ranged from 14 to 64 years (mean 41.8 years). The follow-up period ranged from 6 to 279 months (mean 112.4 months). In the initial 17 patients (Group A), the procedure to prevent arachnoidal adhesion consisted of the layer-to-layer closure of three meninges and laminoplasty. In the subsequently treated eight patients (Group B), the authors performed an alternative technique that included pial suturing, dural closure with Gore-Tex membrane—assisted patch grafting, and expansive laminoplasty. In Group A, postoperative adhesion was radiologically detected in eight cases (47%), and delayed neurological deterioration secondary to posterior tethering of the cord was found in five cases. In Group B, there was no evidence of adhesive posterior tethering or delayed neurological deterioration. A significant intergroup statistical difference was demonstrated for radiologically documented posterior tethering (p < 0.05, Fisher exact test). Moreover, patients with radiologically demonstrated posterior tethering suffered a significant delayed neurological functional deterioration (p < 0.01, Fisher exact test). Conclusions. This new technique for closure of the surgical wound is effective in preventing of postoperative posterior spinal cord tethering after excision of spinal ependymoma.

A positron emission tomography study of cerebrovascular reserve before and after shunt surgery in patients with idiopathic chronic hydrocephalus

1999 ◽  
Vol 91 (4) ◽  
pp. 605-609 ◽  
Author(s):  
Petra M. Klinge ◽  
Georg Berding ◽  
Thomas Brinker ◽  
Wolfram H. Knapp ◽  
Madjid Samii
Keyword(s):  
Positron Emission Tomography ◽  
Emission Tomography ◽  
Chronic Hydrocephalus ◽  
Content Type ◽  
Cerebrovascular Reserve ◽  
Shunt Placement ◽  
Positron Emission ◽  
Group A ◽  
Group B ◽  
Fine Print

Object. In this study the authors use positron emission tomography (PET) to investigate cerebral blood flow (CBF) and cerebrovascular reserve (CVR) in chronic hydrocephalus.Methods. Ten patients whose mean age was 67 ± 10 years (mean ± standard deviation [SD]) were compared with 10 healthy volunteers who were 25 ± 3 years of age. Global CBF and CVR were determined using 15O—H2O and PET prior to shunt placement and 7 days and 7 months thereafter. The CVR was measured using 1 g acetazolamide. Neurological status was assessed based on a score assigned according to the methods of Stein and Langfitt.Seven months after shunt placement, five patients showed clinical improvement (Group A) and five did not (Group B). The average global CBF before shunt deployment was significantly reduced in comparison with the control group (40 ± 8 compared with 61 ± 7 ml/100 ml/minute; mean ± SD, p < 0.01). In Group A the CBF values were significantly lower than in Group B (36 ± 7 compared with 44 ± 8 ml/100 ml/minute; p < 0.05). The CVR before surgery, however, was not significantly different between groups (Group A = 43 ± 21%, Group B = 37 ± 29%). After shunt placement, there was an increase in the CVR in Group A to 52 ± 37% after 7 days and to 68 ± 47% after 7 months (p < 0.05), whereas in Group B the CVR decreased to 14 ± 18% (p < 0.05) after 7 days and returned to the preoperative level (39 ± 6%) 7 months after shunt placement.Conclusions. The preliminary results indicate that a reduced baseline CBF before surgery does not indicate a poor prognosis. Baseline CBF before shunt placement and preoperative CVR are not predictive of clinical outcome. A decrease in the CVR early after shunt placement, however, is related to poor late clinical outcome, whereas early improvement in the CVR after shunt placement indicates a good prognosis.

Age and outcome after aneurysmal subarachnoid hemorrhage: why do older patients fare worse?

1996 ◽  
Vol 85 (3) ◽  
pp. 410-418 ◽  
Author(s):  
Giuseppe Lanzino ◽  
Neal F. Kassell ◽  
Teresa P. Germanson ◽  
Gail L. Kongable ◽  
Laura L. Truskowski ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
Subarachnoid Hemorrhage ◽  
Age Groups ◽  
Age Group ◽  
Content Type ◽  
Poor Outcome ◽  
Symptomatic Vasospasm ◽  
Age Related ◽  
Increased Risk ◽  
Fine Print

✓ Advanced age is a recognized prognostic indicator of poor outcome after subarachnoid hemorrhage (SAH). The relationship of age to other prognostic factors and outcome was evaluated using data from the multicenter randomized trial of nicardipine in SAH conducted in 21 neurosurgical centers in North America. Among the 906 patients who were studied, five different age groups were considered: 40 years or less, 41 to 50, 51 to 60, 61 to 70, and more than 71 years. Twenty-three percent of the individuals enrolled were older than 60 years of age. Women outnumbered men in all age groups. Level of consciousness (p = 0.0002) and World Federation of Neurological Surgeons grade (p = 0.0001) at admission worsened with advancing age. Age was also related to the presence of a thick subarachnoid clot (p = 0.0001), intraventricular hemorrhage (p = 0.0003), and hydrocephalus (p = 0.0001) on an admission computerized tomography scan. The rebleeding rate increased from 4.5% in the youngest age group to 16.4% in patients more than 70 years of age (p = 0.002). As expected, preexisting medical conditions, such as diabetes (p = 0.028), hypertension (p = 0.0001), and pulmonary (p = 0.0084), myocardial (p = 0.0001), and cerebrovascular diseases (p = 0.0001), were positively associated with age. There were no age-related differences in the day of admission following SAH, timing of the surgery and/or location, and size (small vs. large) of the ruptured aneurysm. During the treatment period, the incidence of severe complications (that is, those complications considered life threatening by the reporting investigator) increased with advancing age, occurring in 28%, 33%, 36%, 40%, and 46% of the patients in each advancing age group, respectively (p = 0.0002). No differences were observed in the reported frequency of surgical complications. No age-related differences were found in the overall incidence of angiographic vasospasm; however, symptomatic vasospasm was more frequently reported in the older age groups (p = 0.01). Overall outcome, assessed using the Glasgow Outcome Scale at 3 months post-SAH, was poorer with advancing age (p < 0.001). Multivariate analysis of overall outcome, adjusting for the different prognostic factors, did not remove the age effect, which suggests that the aging brain has a less optimal response to the initial bleeding. Age as a risk factor is a continuum; however, there seems to be a significant increased risk of poor outcome after the age of 60 years.

Suboccipital and cervical chordomas: the value of aggressive treatment at first presentation of the disease

2002 ◽  
Vol 97 (5) ◽  
pp. 1070-1077 ◽  
Author(s):  
Alexandre Carpentier ◽  
Marc Polivka ◽  
Alexandre Blanquet ◽  
Guillaume Lot ◽  
Bernard George
Keyword(s):  
Clinical Symptoms ◽  
Rank Test ◽  
Aggressive Treatment ◽  
Actuarial Survival ◽  
High Tendency ◽  
Content Type ◽  
Log Rank Test ◽  
Group A ◽  
Group B ◽  
Fine Print

Object. Chordoma is a locally invasive tumor with a high tendency for recurrence for which radical resection is generally recommended. To assess the benefits of aggressive treatment of chordomas, the authors compared results in patients treated aggressively at the first presentation of this disease with results in patients who were similarly treated, but after recurrence. Methods. Among 36 patients with cervical chordomas who were treated at the authors' institution, 22 underwent primary aggressive treatment (Group A) and 14 were treated secondarily after tumor recurrence (Group B). Two cases were excluded from Group A because of unrelated early deaths and three from Group B because of insufficient pre- or postoperative data. Most tumors were located at the suboccipital level and only eight cases at a level below C-2. Radiotherapy and proton therapy were similarly conducted in both groups of patients. The actuarial survival rates were 80 and 65% at 5 and 10 years, respectively, in Group A patients and 50 and 0% at 5 and 10 years, respectively, in Group B patients (p = 0.049, log-rank test). The actuarial recurrence-free rates were 70 and 35% at 5 and 10 years, respectively, in Group A and 0% at 3 years in Group B (p < 0.0001, log-rank test). The numbers of recurrences per year were 0.15 in Group A and 0.62 in Group B (p > 0.05). All other parameters that were analyzed (patient age, delay before diagnosis, clinical symptoms, chondroid type of lesion, and histological features) did not prove to influence prognosis in a statistically significant manner. Conclusions. Aggressive therapy, combining as radical a resection as possible with radiotherapy, seems to improve the prognoses of suboccipital and cervical chordomas when applied at the patient's first presentation with the disease.

Reflections upon the nature and management of intracranial and intraspinal vascular malformations and fistulae

1994 ◽  
Vol 80 (4) ◽  
pp. 606-616 ◽  
Author(s):  
Sean Mullan
Keyword(s):  
Sinus Thrombosis ◽  
Vascular Malformations ◽  
Venous Malformation ◽  
Venous Pressure ◽  
Venous Occlusion ◽  
Vein Of Galen ◽  
Content Type ◽  
Permanent Cure ◽  
Glue Embolization ◽  
Fine Print

✓ Evidence is presented that dural fistulae are preceded by sinus thrombosis and that their danger lies in arterialized venous pressure within the cranium or the orbit. Arterial side occlusion leads to recurrence, while venous side occlusion leads to permanent cure. Vein of Galen aneurysms embrace some features of cerebral arteriovenous malformations (AVM's), namely a reticulum, and some features of dural fistulae, namely evidence of previous sinus anomaly and direct drainage into a sinus. These aneurysms are also permanently cured by venous side thrombosis, although the dangers inherent in their reticulum demand that this be done in stages or preceded by arterial side embolization. A very limited experience with venous end occlusion of cerebral (and spinal) AVM's suggests that they, too, can be permanently cured by venous side occlusion without excision. Their reticulum demands maximum, multistage, preliminary arterial side embolization together with intraoperative hypotension during the venous occlusion stage in order to minimize intracerebral hemorrhage or swelling. Schematic models of both fistulae and malformations are presented, together with reasons why particulate embolization is safer than glue embolization. The theory is advanced that dural fistulae, vein of Galen aneurysms, and AVM's are venous- rather than arterial-based lesions, which is consistent with the experience that permanent cure has been effected by venous side occlusion without excision in all three anomalies. It is speculated that there may be a developmental link between AVM and the venous malformation, the AVM being essentially a fistulized venous malformation.

Age-related changes in intracranial compartment volumes in normal adults assessed by magnetic resonance imaging

1996 ◽  
Vol 84 (6) ◽  
pp. 982-991 ◽  
Author(s):  
Mitsunori Matsumae ◽  
Ron Kikinis ◽  
István A. Mórocz ◽  
Antonio V. Lorenzo ◽  
Tamás Sándor ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Brain Volume ◽  
Intracranial Volume ◽  
Mr Image ◽  
Content Type ◽  
Age Related ◽  
The Difference ◽  
Normal Adults ◽  
Fine Print ◽  
Age Related Changes

✓ Magnetic resonance (MR) image—based computerized segmentation was used to measure various intracranial compartments in 49 normal volunteers ranging in age from 24 to 80 years to determine age-related changes in brain, ventricular, and extraventricular cerebrospinal fluid (CSF) volumes. The total intracranial volume (sum of brain, ventricular, and extraventricular CSF) averaged 1469 ± 102 cm3 in men and 1289 ± 111 cm3 in women. The difference was attributable primarily to brain volume, which accounted for 88.6% of the respective intracranial volumes in both sexes, but was significantly larger in men (1302 ± 112 cm3) than in women (1143 ± 105 cm3). In both, the cranial CSF volume averaged 11.4%. Total intracranial volume did not change with age, although the normalized brain volume of both men and women began to decrease after the age of 40 years. This decrease was best reflected by expansion of the extraventricular CSF volume which, after the age of 50 years, was more marked in men than in women. The volume of the cranial CSF, as determined by MR image-based computerized segmentation, is considerably larger than traditionally accepted and resides mostly extraventricularly. Expansion of CSF volume with age provides a good index of brain shrinkage although evolving changes and growth of the head with age tend to confound the results.

Tethered cord syndrome of delayed onset following repair of myelomeningocele

1988 ◽  
Vol 69 (3) ◽  
pp. 393-398 ◽  
Author(s):  
Norihiko Tamaki ◽  
Kunio Shirataki ◽  
Noriaki Kojima ◽  
Yoshiteru Shouse ◽  
Satoshi Matsumoto
Keyword(s):  
Preoperative Evaluation ◽  
Tethered Cord ◽  
Tethered Cord Syndrome ◽  
Clear Understanding ◽  
Mr Images ◽  
Content Type ◽  
Delayed Onset ◽  
Group A ◽  
Group B ◽  
Fine Print

✓ Nine (15%) of 60 patients with repaired myelomeningocele exhibited late deterioration of neurological function with a tethered cord syndrome. Dense adhesions at the lowest laminae and at the site of previous repair were the most common findings at surgery. Postoperatively, 71% of the patients improved. Magnetic resonance (MR) imaging was performed in 29 of the 60 patients. Eight of these 29 patients exhibited a tethered cord syndrome. The MR images in all patients showed a low-lying conus fixed at the site of previous repair, irrespective of the presence or absence of a tethered cord syndrome. The MR images were classified into two groups depending upon the site of adhesions: Group A had potential sites of tethering at the ventral aspect of the last laminae and at the site of previous repair, and Group B showed the adhesion point only at the site of previous repair. Most patients with a tethered cord syndrome were found to be in Group A; conversely, most patients without the syndrome were in Group B. An enlarged low conus was seen in symptomatic patients more commonly than in those without this syndrome. It is concluded that the presence of adhesions specifically at the last laminae as well as a widened low-lying conus may be the cause of tethered cord syndrome in patients with repaired myelomeningoceles. A clear understanding of the tethering process and preoperative evaluation of potential sites of tethering, based on the MR findings, are very important for planning surgery. The release of adhesions at the lowest laminae by laminectomy appeared essential for improvement.

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