bluuebunny/crossref_metadata_2025_split huggingface dataset:
Results of a prospective randomized trial for treatment of severely brain-injured patients with hyperbaric oxygen
Authors: Rockswold Gaylan L. , Ford Sandra E. , Anderson David C. , Bergman Thomas A. , Sherman Robert E. 
Published: May 2009

✓ The authors enrolled 168 patients with closed-head trauma into a prospective trial to evaluate the effect of hyperbaric oxygen in the treatment of brain injury. Patients were included if they had a total Glasgow Coma Scale (GCS) score of 9 or less for at least 6 hours. After the GCS score was established and consent obtained, the patient was randomly assigned, stratified by GCS score and age, to either a treatment or a control group. Hyperbaric oxygen was administered to the treatment group in a monoplace chamber every 8 hours for 1 hour at 1.5 atm absolute; this treatment course continued for 2 weeks or until the patient was either brain dead or awake. An average of 21 treatments per patient was given.
Outcome was assessed by blinded independent examiners. The entire group of 168 patients was followed for 12 months, with two patients lost to follow-up study. The mortality rate was 17% for the 84 hyperbaric oxygen-treated patients and 32% for the 82 control patients (chi-squared test, 1 df, p = 0.037). Among the 80 patients with an initial GCS score of 4, 5, or 6, the mortality rate was 17% for the hyperbaric oxygen-treated group and 42% for the controls (chi-squared test, 1 df, p = 0.04). Analysis of the 87 patients with peak intracranial pressures (ICP) greater than 20 mm Hg revealed a 21 % mortality rate for the hyperbaric oxygen-treated patients, as opposed to 48% for the control group (chi-squared test, 1 df, p = 0.02). Myringotomy to reduce pain during hyperbaric oxygen treatment helped to reduce ICP. Analysis of the outcome of survivors reveals that hyperbaric oxygen treatment did not increase the number of patients in the favorable outcome categories (good recovery and moderate disability). The possibility that a different hyperbaric oxygen treatment paradigm or the addition of other agents, such as a 21-aminosteroid, may improve quality of survival is being explored.
Blood pressure and intracranial pressure-volume dynamics in severe head injury: relationship with cerebral blood flow
Authors: Bouma Gerrit J. , Muizelaar J. Paul , Bandoh Kuniaki , Marmarou Anthony 
Published: May 2009

✓ Increased brain tissue stiffness following severe traumatic brain injury is an important factor in the development of raised intracranial pressure (ICP). However, the mechanisms involved in brain tissue stiffness are not well understood, particularly the effect of changes in systemic blood pressure. Thus, controversy exists as to the optimum management of blood pressure in severe head injury, and diverging treatment strategies have been proposed. In the present study, the effect of induced alterations in blood pressure on ICP and brain stiffness as indicated by the pressure-volume index (PVI) was studied during 58 tests of autoregulation of cerebral blood flow in 47 comatose head-injured patients. In patients with intact autoregulation mechanisms, lowering the blood pressure caused a steep increase in ICP (from 20 ± 3 to 30 ± 2 mm Hg, mean ± standard error of the mean), while raising blood pressure did not change the ICP. When autoregulation was defective, ICP varied directly with blood pressure. Accordingly, with intact autoregulation, a weak positive correlation between PVI and cerebral perfusion pressure was found; however, with defective autoregulation, the PVI was inversely related to cerebral perfusion pressure. The various blood pressure manipulations did not significantly alter the cerebral metabolic rate of oxygen, irrespective of the status of autoregulation.
It is concluded that the changes in ICP can be explained by changes in cerebral blood volume due to cerebral vasoconstriction or dilatation, while the changes in PVI can be largely attributed to alterations in transmural pressure, which may or may not be attenuated by cerebral arteriolar vasoconstriction, depending on the autoregulatory status. The data indicate that a decline in blood pressure should be avoided in head-injured patients, even when baseline blood pressure is high. On the other hand, induced hypertension did not consistently reduce ICP in patients with intact autoregulation and should only be attempted after thorough assessment of the cerebrovascular status and under careful monitoring of its effects.
Selection and combination of various endovascular techniques in the treatment of giant aneurysms
Authors: Taki Waro , Nishi Shogo , Yamashita Kohsuke , Sadatoh Akiyo , Nakahara Ichiro , Kikuchi Haruhiko , Iwata Hiroo 
Published: May 2009

✓ Between April, 1989, and January, 1991, a total of 19 cases of giant aneurysm were treated by the endovascular approach. The patients included seven males and 12 females aged 15 to 72 years. Detachable balloons, occlusion coils, and ethylene vinyl alcohol copolymer liquid were used as embolic materials. In seven cases, thrombosis of the aneurysmal sac and/or base was achieved while sparing the parent arterial flow; complete obliteration of the aneurysm was achieved in four of these. Of these four patients, the thrombotic material was a detachable balloon in two, a combination of a detachable balloon and coils in one, and occlusion liquid in one. In the other three cases, complete occlusion was not achieved; one aneurysm was occluded with a detachable balloon and two with coils. In 11 patients, the parent artery was occluded either by trapping or by proximal arterial occlusion, and all patients showed complete occlusion of the aneurysms. In one patient, a combined bypass procedure and parent artery occlusion was performed.
Among the 19 cases in this series there were four transient ischemic attacks, one reversible ischemic neurological deficit, and one death due to aneurysmal rupture during the procedure. Two patients died in the follow-up period, one from pneumonia 2 months postoperatively and the other from acute cardiac failure 2 weeks following surgery. Both deaths were unrelated to the endovascular procedure. It is concluded that the endovascular treatment of giant aneurysms remains difficult because of the large and irregular shape of the aneurysmal base and thrombus in the aneurysmal sac. The proper selection and combination of the available endovascular techniques is therefore of critical importance.
Long-term results of spinal accessory nerve-facial nerve anastomosis
Authors: Ebersold Michael J. , Quast Lynn M. 
Published: May 2009

✓ A number of methods have been developed to reduce the cosmetic and functional disability resulting from facial nerve loss. It has often been suggested that the major trunk of the spinal accessory nerve should not be sacrificed for providing dynamic facial function because of shoulder disability and pain. A review of Mayo Clinic records has revealed that, between the years of 1975 and 1983, 25 patients underwent spinal accessory nerve-facial nerve anastomosis using the major division (branch to the trapezius muscle) of the spinal accessory nerve.There were 11 males and 14 females, ranging in age from 16 to 60 years (mean 41 years). The interval between facial nerve loss and anastomosis was 1 week to 34 months (mean 4.62 months). The duration of follow-up study ranged from 7 to 15 years (mean 10.8 years).Twenty patients had no complaints or symptoms related to their shoulder or arm at the time of this review and no patient had significant shoulder morbidity. The facial function achieved was “minimal” in five cases, “moderate” in six, and good to excellent in 14. Most patients appeared to benefit significantly from the spinal accessory nerve-facial nerve anastomosis. The morbidity of the procedure seemed quite minimal even in the young and active. The authors continue to believe that the spinal accessory nerve-facial nerve anastomosis, even when using the major trunk of the spinal accessory nerve, is a very useful and beneficial procedure.
An in vitro comparative study of conducting vessels and penetrating arterioles after experimental subarachnoid hemorrhage in the rabbit
Authors: Vollmer Dennis G. , Takayasu Masakazu , Dacey Ralph G. 
Published: May 2009

✓ The reactivity of rabbit basilar artery and penetrating arteriolar microvessels was studiedin vitrousing an isometric-tension measurement technique and an isolated perfused arteriole preparation, respectively. Comparisons were made between reactivities of normal vessels and those obtained from animals subjected to experimental subarachnoid hemorrhage (SAH) 3 days prior to examination. Subarachnoid hemorrhage produced significant increases in basilar artery contraction in response to increasing concentrations of serotonin (5-hydroxytryptamine) (10−9to 10−5M) and prostaglandin F2α(10−9to 10−5M) when compared to normal arteries. In addition, SAH attenuated the relaxing effect of acetylcholine following serotonin-induced contraction and of adenosine triphosphate after KCl-induced basilar artery contractions. In contrast to the changes observed in large arteries, cerebral microvessels did not demonstrate significant differences in spontaneous tone or in reactivity to a number of vasoactive stimuli including application of calcium, serotonin, and acetylcholine. On the other hand, small but significant changes in arteriolar responsiveness to changes in extraluminal pH and to application of KCl were noted.Findings from this study suggest that intracerebral resistance vessels of the cerebral microcirculation are not greatly affected by the presence of subarachnoid clot, in contrast to the large arteries in the basal subarachnoid space. The small changes that do occur are qualitatively different from those observed for large arteries. These findings are consistent with the observation of significant therapeutic benefit with the use of calcium channel blockers without changes in angiographically visible vasospasm in large vessels. It is likely, therefore, that calcium antagonists may act to decrease total cerebrovascular resistance at the level of the relatively unaffected microcirculation after SAH without changing large vessel diameter.
Endovascular treatment of posterior circulation aneurysms by electrothrombosis using electrically detachable coils
Authors: Guglielmi Guido , Viñuela Fernando , Duckwiler Gary , Dion Jacques , Lylyk Pedro , Berenstein Alex , Strother Charles , Graves Virgil , Halbach Van , Nichols Douglas , Hopkins Nick , Ferguson Robert , Sepetka Ivan 
Published: May 2009

✓ In a multicenter study, 120 patients with intracranial aneurysms presenting a high surgical risk were treated using electrolytically detachable coils and electrothrombosis via an endovascular approach. The results of treatment in patients with posterior fossa aneurysms (42 patients with 43 aneurysms) are presented. The most frequent clinical presentation was subarachnoid hemorrhage (24 cases). The clinical follow-up periods ranged from 1 week to 18 months. Complete aneurysm occlusion was obtained in 13 of 16 aneurysms with a small neck and in four of 26 wide-necked aneurysms. A 70% to 98% thrombosis of the aneurysm was achieved in 22 of 26 aneurysms with a wide neck and in three of 16 small-necked aneurysms. One aneurysm could not be treated due to a technical complication. Two cases required postprocedural surgical clipping of a residual aneurysm.
One patient (originally in Hunt and Hess Grade V) experienced procedural rupture of the aneurysm requiring an emergency parent artery occlusion. He eventually died 5 days later. Another patient (originally in Grade IV) had coil migration and posterior cerebral artery territory ischemia. A third patient developed a permanent neurological deficit (hemianopsia) after complete occlusion of a wide-necked basilar bifurcation aneurysm. One patient, harboring an inoperable giant basilar bifurcation aneurysm, died from aneurysm bleeding 18 months after partial occlusion.
Overall morbidity and mortality rates related to treatment were 4.8% (two cases) and 2.4% (one case), respectively (2.6% and 0% if considering only patients in Hunt and Hess Grades I, II, and III).
It is suggested that this technique is a viable alternative in the management of patients with posterior fossa aneurysms associated with high surgical risk. Longer angiographic and clinical follow-up study is necessary to determine the long-term efficacy of this recently developed endovascular occlusion technique. Close postoperative angiographic and clinical monitoring of patients with wide-necked subtotally occluded aneurysms is mandatory to check for potential aneurysmal recanalization, regrowth, and rupture.
The influence of transoral odontoid resection on stability of the craniovertebral junction
Authors: Dickman Curtis A. , Locantro Jacqueline , Fessler Richard G. 
Published: May 2009

✓ Twenty-seven cases of craniovertebral junction compression treated with transoral surgery were reviewed to assess the influences of pathological processes and surgical interventions on spinal stability. All patients presented with signs and symptoms of spinal-cord or brain-stem dysfunction. Pathology included rheumatoid arthritis in 11 patients, congenital osseous malformations in 11, spinal fractures in two, plasmacytoma in one, osteomyelitis in one, and a gunshot injury in one. Instability was defined as clear radiographic evidence of mobile subluxation in conjunction with clinical assessment.
Of 19 patients (70%) requiring internal fixation, nine underwent upper cervical fusion and 10 had occipitocervical fusion. When instability occurred, all subluxations were at the C1–2 level. There were no occipitoatlantal subluxations. Eight patients (30%) had preoperative instability of the craniovertebral junction due solely to their pathology, 11 patients (40%) suffered instability after transoral surgery, and eight (30%) were without clinical or radiographic evidence of instability (mean follow-up period 14 months).
Craniovertebral junction instability predominated among patients with rheumatoid arthritis: 91% required fusion and 45% presented with pre-existing instability. Among individuals with congenital osseous malformations, 45% required fusion and only one patient (9%) had pre-existing instability. Patients who required subsequent posterior decompression of a Chiari malformation were at risk for developing instability; three of four became unstable after posterior decompression.
Transoral resection of the dens, the anterior arch of C-1, and the lower clivus does not fully destabilize the spine; however, this operation may potentiate incipient pathological instability. The primary determinants of instability are the extent of pathological bone destruction, ligamentous weakening, and operative bone removal. Long-term follow-up monitoring is needed after transoral surgery to detect cases of late instability.
Intracavitary brachytherapy of cystic craniopharyngiomas
Authors: van den Berge J. Herbert , Blaauw Gerhard , Breeman Wout A. P. , Rahmy Ali , Wijngaarde Rinia 
Published: May 2009

✓ Visual function, endocrinological status, and radiological outcome are reported in 31 patients harboring a cystic craniopharyngioma, who underwent 35 intracavitary brachytherapy procedures with yttrium-90. In 26 of these patients intracavitary brachytherapy was the primary treatment. The follow-up period ranged from 2 to 80 months (41 ± 22 months, mean ± standard deviation). Five patients died from tumor-related causes. Endocrine recovery was modest.Prior to brachytherapy, visual acuity was diminished in 38 eyes and field defects were present in 46. Funduscopy before treatment revealed optic atrophy in 47% of the eyes. Visual acuity improved in 29% of the eyes studied, remained stable in 13%, and deteriorated in 58%. Visual field defects improved in 28% of the eyes studied, remained stable in 20%, and deteriorated in 52%. The possible causes for deterioration in visual function are discussed.Complete resolution of 10 cysts was noted. In 12 patients the size of the cyst decreased; however, in three of these patients new cyst formation took place. The cyst size stabilized in six cases and increased in three. Although there is still a substantial degree of visual function deterioration following intracavitary brachytherapy, morbidity is otherwise low, making this treatment modality a reasonable alternative to craniotomy.
Aggravation of vasogenic cerebral edema by multiple-dose mannitol
Authors: Kaufmann Anthony M. , Cardoso Erico R. 
Published: May 2009

✓ The authors investigated the pharmacokinetics of mannitol administered for treatment of vasogenic cerebral edema. A cortical cold injury was produced in 23 cats maintained under general anesthesia for 5 or 21 hours. Control animals received no mannitol, while treatment groups received either a single dose or five doses administered at 4-hour intervals of 0.33 gm/kg radiolabeled mannitol. Liquid scintillation counting was carried out to determine the concentrations of mannitol in the cerebral tissue, cerebrospinal fluid, plasma, and urine. Cerebral water content and linear progression of edema were also measured.Rapid plasma clearance prevented accumulation of mannitol after multiple intravenous injections, as 84% ± 2% (mean ± standard error of the mean) of the infused mannitol was excreted through the urine. However, there was progressive accumulation of mannitol within the cerebral tissue, especially in the edematous white matter where it reached a level of 0.33 ± 0.03 mg/gm after five doses, exceeding the trough plasma concentrations by a ratio of 2.69:1. Water content measurement showed that a single dose of mannitol failed to reduce cerebral water content or edema progression at 4 hours postinjection, while multiple doses produced a 3% increase in water content in edematous regions (p > 0.0003). The results of this study demonstrated a reversal of the osmotic concentration gradient between edematous brain and plasma following multiple mannitol injections, associated with exacerbation of vasogenic cerebral edema.
Seizure outcome in patients with surgically treated cerebral arteriovenous malformations
Authors: Piepgras David G. , Sundt Thoralf M. , Ragoonwansi Ashvin T. , Stevens Lorna 
Published: May 2009

✓ A series of 280 cases of cerebral arteriovenous malformations (AVM's) treated surgically between June, 1970, and June, 1989, is reviewed with particular focus on the preoperative seizure history and follow-up seizure status. Follow-up evaluation (mean duration 7.5 years) was achieved in 98% of cases and was accomplished through re-examinations, telephone interviews, and written questionnaires. Overall, 89% of the surviving patients with a follow-up period of greater than 2 years were free of seizures at last examination.
Of the 280 patients in this series. 163 had experienced no seizures preoperatively. A recent follow-up study (with a minimum duration of 2 years or to death) was available in 157 of these 163 cases; 21 patients had died. Of the 136 surviving patients, only eight (6%) were having new ongoing seizures. In the 128 (94%) who had remained seizure-free, 73% were receiving no anticonvulsant agents while 27% were taking anticonvulsant prophylaxis. The 2-year minimum follow-up study in 110 of the 117 patients with preoperative seizures revealed that eight (7%) had died. Of the 102 surviving patients, 85 (83%) were seizure-free (with 48% no longer receiving anticonvulsant therapy), while 17 (17%) still suffered intermittent seizures. However, of these 17 patients, 13 reported their seizures to be improved compared to preoperatively; the seizures were the same in two patients and were worse in two patients.
An actuarial analysis was conducted comparing the life expectancy of patients following surgery for AVM's with the expected survival of a general white population of the same age and sex in the West Northcentral region of the United States. No statistically significant difference was found. There were seven perioperative deaths (three from cerebral hemorrhage, two from pulmonary emboli, and two from obstruction of venous drainage) and 22 deaths during the follow-up period. Of these 22 deaths, the cause was unknown in four patients, apparently unrelated to the AVM in 13, and directly or indirectly related to the patient's neurological condition prior to surgery or due to surgery performed for resection of the AVM in five.
There was a statistically significant relationship between the size and location of the AVM and the clinical presentation. Patients with small AVM's (< 3 cm) were more likely to present with hemorrhage whereas those with large AVM's were more likely to present with seizures.
Conclusions from this study are: 1) there is a low incidence of a new seizure disorder following surgery: 2) chances for resolution or control of a pre-existing seizure disorder are good: 3) although resolution of seizures or seizure control was achieved postoperatively in AVM's of all sizes, this benefit was highest in smaller as opposed to larger AVM's; and 4) ultimately, there is a good capacity for recovery from pre-existing neurological deficits or those resulting from surgery.
Comparison of regeneration across nerve allografts with temporary or continuous cyclosporin A immunosuppression
Authors: Midha Rajiv , Mackinnon Susan E. , Evans Peter J. , Best Timothy J. , Hare Gregory M. T. , Hunter Dan A. , Falk-Wade Judy A. 
Published: May 2009

✓ The efficacy of short-term immunosuppression in a nerve allograft model was examined by comparing regeneration across peripheral nerve allografts with either temporary (12 weeks) or continuous (30 weeks) cyclosporin A treatment. One-hundred fifty Lewis rats received 2-cm nerve grafts from allogeneic ACI or syngeneic Lewis rat donors and were allocated to the following groups: allogeneic grafts and continuous cyclosporin A, with 18 weeks (20 rats) or 30 weeks (20 rats) of survival after graft placement; allogeneic grafts and temporary cyclosporin A, with 12 weeks (10 rats), 18 weeks (20 rats), or 30 weeks (20 rats) of survival; and control rats with allogeneic and syngeneic grafts, no cyclosporin A, with 12, 18, or 30 weeks (10 rats each) of survival. Functional regeneration across the nerve grafts was serially assessed with walking-track analysis. Endpoint evaluations included electrophysiological, histological, and morphometric studies.
Both walking-track and electrophysiological function reached a plateau at a significantly worse level in nonimmunosuppressed allograft recipients than in syngeneic or treated allograft recipients. The group with temporary therapy experienced significant worsening in both motor and electrophysiological function at Week 18, 6 weeks after cyclosporin A withdrawal, compared to the group with continuous treatment. At Week 30, motor and electrophysiological function in the temporary-treatment group recovered to levels similar to those of the syngeneic and continuous cyclosporin A groups. Histological assessment of the graft segments from the temporary cyclosporin A group at 18 weeks showed evidence of rejection, with mononuclear cell infiltration and demyelination; morphometric evaluation demonstrated significantly decreased numbers of nerve fibers in the distal host segment. These histological and morphometric changes were no longer present in the nerves from the temporarily immunosuppressed rats at Week 30.
Withdrawal of immunosuppression after successful regeneration through nerve allografts results in short-term graft rejection. Eventual restoration of graft histological and function parameters is comparable to continuously immunosuppressed rats. Temporary immunosuppression of nerve allograft recipients is feasible.