bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth hormone deficiency following radiation therapy of primary brain tumors in children
Authors: Kanev Paul M. , Lefebvre John F. , Mauseth Richard S. , Berger Mitchel S. 
Published: May 2009

✓ The medical records of 123 patients treated for brain tumors at Children's Hospital and Medical Center, Seattle, Washington, between 1985 and 1987 were reviewed. The endocrinological complications of radiation therapy and the effectiveness of growth hormone (GH) replacement therapy were assessed. These were the first 2 years after synthetic GH became available. The disease pathology was confirmed at craniotomy or biopsy in 108 patients. Ninety-five children completed radiation therapy and 65 of these were alive at the time of review; these 65 children represent the study population. The most common tumor types were medulloblastoma, craniopharyngioma, and ependymoma. Endocrine evaluation was initiated with changes in the patients' growth velocity. Patient workup included skeletal x-ray films for determination of bone age, and analysis of thyroxin, thyroid-stimulating hormone, and somatomedin-C levels. Following l-dopa and clonidine stimulation, provocative studies of GH levels were performed.
Growth hormone failure and short stature were observed in 26 children, most commonly in the 2nd year after tumor treatment. Eight patients with GH failure were also hypothyroid. Hormone replacement therapy was initiated with recombinant GH, 0.05 mg/kg/day, and all children so treated showed an increase in height, with eight patients experiencing catch-up growth. There were no complications of therapy or tumor recurrence.
Studies of baseline bone age and somatomedin-C levels on completion of radiation therapy are recommended. Comprehensive endocrine studies should follow changes in the patients' growth velocity. With early GH replacement, catch-up growth is possible and normal adult heights may be achieved.
Intravascular streaming during carotid artery infusions
Authors: Saris Stephen C. , Blasberg Ronald G. , Carson Richard E. , deVroom Hetty L. , Lutz Robert , Dedrick Robert L. , Pettigrew Karen , Chang Richard , Doppman John , Wright Donald C. , Herscovitch Peter , Oldfield Edward H. 
Published: May 2009

✓ Intra-arterial carotid artery chemotherapy for malignant gliomas is limited by focal injuries to the eye and brain which may be caused by poor mixing of the drug with blood at the infusion site. This inadequate mixing can be eliminated in animal models with diastole-phased pulsatile infusion (DPPI) which creates 1-ml/sec spurts during the slow blood flow phase of diastole. Before treatment with intracarotid cisplatin, 10 patients with malignant gliomas were studied to determine whether intravascular streaming occurs after intracarotid infusion in humans, and if so, if it is reduced with DPPI. Regional cerebral blood flow (rCBF) studies were performed by intravenous injection of H215O and positron emission tomography. This was followed by supraor infraophthalmic internal carotid artery (ICA) injections of H215O with either continuous infusion or DPPI. Local H215O concentration in the brain was determined and the images of radiotracer distribution in the continuous infusion and DPPI studies were compared to the rCBF images. Intravascular streaming of the infusate was identified by a heterogeneous distribution of the infused H215O in brain compared to rCBF.
Extensive and variable intravascular streaming occurred in three patients who received infusions into the supraophthalmic segment of the ICA. Some brain areas received up to 11 times the expected radiotracer delivery, while other regions received as little as one-tenth. This streaming pattern was markedly reduced or eliminated by DPPI. In the five patients who received infraophthalmic infusions, a minimally heterogeneous distribution of the infusate was detected. The authors conclude that extensive intravascular streaming accompanies supraophthalmic ICA infusions in patients. The magnitude of streaming can be substantially reduced or eliminated with DPPI. Those who perform intra-arterial infusion should consider using DPPI to assure uniform drug delivery to brain.
Evidence against leukotrienes as mediators of brain edema
Authors: Unterberg Andreas , Schmidt Walter , Wahl Michael , Ellis Earl F. , Marmarou Anthony , Baethmann Alexander 
Published: May 2009

✓ Leukotrienes are powerful metabolites of arachidonic acid which are known to increase the permeability of peripheral blood vessels. These substances are found in brain tissue in association with cerebral ischemia, and in brain tumors. Therefore, it has been proposed that leukotrienes have a mediator function in brain edema. This hypothesis was subjected to further experimental analysis in this study, in which the authors investigated whether: 1) superfusion of the exposed brain surface with leukotrienes increases the permeability of extraparenchymal blood vessels in vivo; 2) intraparenchymal infusion of leukotrienes induces brain edema; and 3) pharmacological inhibition of leukotriene formation by BW755C, an inhibitor of leukotriene synthesis, reduces formation of brain edema from a standardized traumatic insult.
The pial vessels of the parietal cortex of cats were examined by fluorescence microscopy during cerebral superfusion with the leukotrienes C4 (LTC4), D4 (LTD4), or E4 (LTE4) by using an open cranial window preparation. Intravenous Na+-fluorescein served as an in vivo blood-brain barrier (BBB) indicator. Superfusion of the pia with leukotrienes (up to 2 µM) did not open the barrier to fluorescein, but was associated with a significant constriction (up to 25%) of arterial and venous vessels. In experiments with slow infusion of leukotriene B4 (LTB4) or LTC4 into the white matter of feline brain, the tissue water content was subsequently determined in serial brain slices using the specific gravity method. Tissue water profiles obtained after a 15- µM infusion of either LTB4 or LTC4 were virtually identical with those of control animals infused with mock cerebrospinal fluid. Thus, neither LTB4 nor LTC4 led to an augmentation of infusion-induced brain edema. In a final series, a cold lesion of the left parietal cortex was induced in rabbits. Twenty-four hours later, swelling of the exposed hemisphere was quantified by gravimetrical comparison of its weight with that of the contralateral nontraumatized hemisphere. Eight animals received BW755C intravenously prior to and after trauma to inhibit formation of leukotrienes. Seven rabbits were infused with an equivalent volume of saline as a control study. The resulting hemispheric swelling was 7.7% ± 0.6% (mean ± standard error of the mean) 24 hours later in animals receiving BW755C and 7.8% ± 1.2% in the control group, indicating that inhibition of leukotrienes was ineffective in preventing formation of vasogenic brain edema.
The findings demonstrate that leukotrienes administered to the brain in concentrations occurring under pathological conditions do not open the BBB nor do they induce brain edema. Moreover, formation of brain edema from a standard insult was not therapeutically influenced by inhibition of leukotriene synthesis. Thus, the current findings taken together do not support a role of leukotrienes as mediators in brain edema.
Ultraprofound hypothermia with complete blood substitution in a canine model
Authors: Bailes Julian E. , Leavitt Marc L. , Teeple Edward , Maroon Joseph C. , Shih Shou-Ren , Marquardt Merlin , El Rifai Amr , Manack Leo 
Published: May 2009

✓ The potential for hypothermia to prevent or ameliorate ischemic injury to the central nervous system is well known. To determine if a more prolonged period of metabolic suppression with blood substitution is possible, a method was developed to lower body temperature to near the freezing point. Eight adult mongrel dogs underwent closed-chest extracorporeal circulation with both external and internal body cooling. As they were cooled, progressive hemodilution was employed until complete exsanguination and blood substitution with an aqueous solution was accomplished. Continuous circulation and a core temperature at a mean of 1.7°C were maintained from 2½ to 3 hours. After rewarming to 20°C, the animals were autotransfused and allowed to recover. Of the eight animals, two died due to technical factors related to cardiac defibrillation. Of the six surviving animals, five survived over a long period and one died on the 10th postoperative day with hepatorenal failure resulting from a presumed blood transfusion incompatability reaction. All six showed normal neurological function and kennel behavior, except one dog with mild weakness of a hindlimb. When the dogs were sacrificed 1 to 2 months postoperatively, all organs were histologically normal. Specifically, there was no gross or microscopic evidence of ischemic or hypoxic injury to any central nervous system structures.
This pilot study demonstrates that it is possible to successfully achieve complete exsanguination, blood substitution, and ultraprofound body temperature, while continuous circulation of the blood substitute is maintained. With the capability of controlling and repeatedly performing washout of the extracellular environment and by reaching lower temperatures, it may be possible to attain greater cellular metabolic suppression. This perhaps will extend the allowable times for circulatory arrest procedures. In addition, “bloodless ischemia” may be beneficial in removing both blood substances and formed elements which may mediate organ ischemia. With replacement of blood at warm temperatures, coagulopathy is avoided. This preliminary evidence demonstrates potential in the combination of ultraprofound hypothermia and complete blood component substitution. However, further study is required to confirm the potential of achieving circulatory arrest of longer duration.
Treatment of unresectable meningiomas with the antiprogesterone agent mifepristone
Authors: Grunberg Steven M. , Weiss Martin H. , Spitz Irving M. , Ahmadi Jamshid , Sadun Alfredo , Russell Christy A. , Lucci Lois , Stevenson Lani L. 
Published: May 2009

✓ The possibility that meningioma growth may be related to female sex hormone levels is suggested by several lines of evidence. Meningiomas are twice as common in women as in men, have been observed to wax and wane with pregnancy, and are positively associated with breast cancer. A physiological explanation for these phenomena is provided by the finding of steroid hormone receptors in meningiomas. However, unlike breast cancer, meningiomas are much more commonly positive for progesterone receptors than for estrogen receptors.
The authors initiated a study on long-term oral therapy of unresectable meningiomas with the antiprogesterone mifepristone (RU486). Fourteen patients received mifepristone in daily doses of 200 mg for periods ranging from 2 to 31+ months (≥ 6 months in 12 patients). Five patients have shown signs of objective response (reduced tumor measurement on computerized tomography scan or magnetic resonance image, or improved visual field examination). Three have also experienced subjective improvement (improved extraocular muscle function or relief from headache). The side effects of long-term mifepristone therapy have been mild. Fatigue was noted in 11 of the 14 patients. Other side effects included hot flashes in five patients, gynecomastia in three, partial alopecia in two, and cessation of menses in two. Long-term therapy with mifepristone is a new therapeutic option that may have efficacy in cases of unresectable benign meningioma.
Somatosensory function following dorsal root entry zone lesions in patients with neurogenic pain or spasticity
Authors: Jeanmonod Daniel , Sindou Marc 
Published: May 2009

✓ The goal of this study was to assess the effects of the dorsal root entry zone (DREZ) lesioning procedure, microsurgical DREZ-otomy (MDT), on spinal cord somatosensory function based on peri- and intraoperative clinical and electrophysiological data. The study was performed prospectively on a series of 20 patients suffering from either chronic neurogenic pain or spasticity. Physiological observations were made of the intraoperative evoked electrospinographic recordings as collected from the surface of the spinal cord.
The MDT procedure produced analgesia or severe hypalgesia, moderate hypesthesia, and only slight deficits in proprioception and cutaneous spatial discrimination on the body segments operated on. These clinical data correlated well with evoked electrospinographic recordings, which showed a moderate effect of MDT on presynaptic compound action potentials recorded from the spinal cord (N11 and N21), a partial or even reversible effect on the cortical postcentral N20 wave, a more marked effect on the postsynaptic dorsal horn waves N13 and N24 related to large primary afferent fibers, and a disappearance of dorsal horn waves related to finer afferents (N2 and possibly N3). These data provide evidence for an acceptably selective action of MDT on spinal cord nociceptive mechanisms, and for a partial, often slight, involvement of the other somatosensory domains. The presence of abnormal evoked electrospinographic waves is discussed in relation to the mechanisms of neurogenic pain and spasticity. The hypothesis of a “retuning” of the dorsal horn as the mode of action of MDT is presented.
Cavernous malformations of the brain stem
Authors: Zimmerman Richard S. , Spetzler Robert F. , Lee K. Stuart , Zabramski Joseph M. , Hargraves Ronald W. 
Published: May 2009

✓ Once they become symptomatic, cavernous malformations of the brain stem appear to cause progressive morbidity from repetitive hemorrhage, and can even be fatal. Twenty-four patients with long-tract and/or
cranial nerve findings from their cavernous malformations of the brain stem were seen for initial evaluation or surgical consultation and thereafter received either surgical or continued conservative treatment. The decision to operate was based on the proximity of the cavernous malformation to the pial surface of the brain stem, the patient's neurological status, and the number of symptomatic episodes. Sixteen patients were treated by definitive surgery directed at excision of their malformation. In four patients, associated venous malformations influenced the surgical approach and their recognition avoided the risk of inappropriate excision of the venous malformation. Although some of the 16 patients had transient, immediate, postoperative worsening of their neurological deficits, the outcome of all except one was the same or improved. Only one patient developed recurrent symptoms: a new deficit 2½ years after surgery required reoperation after regrowth of the cavernous malformation. She has been neurologically stable since the second surgery. One patient died 6 months postoperatively from a shunt infection and sepsis. The eight conservatively treated patients are followed with annual magnetic resonance imaging studies. One has a dramatic associated venous malformation. Seven patients have either minor intermittent or no symptoms, and the eighth died from a hemorrhage 1 year after his initial presentation.
Based on these results, surgical extirpation of symptomatic cavernous malformations of the brain stem appears to be the treatment of choice when a patient is symptomatic, the lesion is located superficially, and an operative approach can spare eloquent tissue. When cavernous malformations of the brain stem are completely excised, cure appears permanent.
Stereotactic management of colloid cysts: factors predicting success
Authors: Kondziolka Douglas , Lunsford L. Dade 
Published: May 2009

✓ Stereotactic aspiration is a valuable surgical alternative for colloid cysts when used alone or in conjunction with microsurgical resection. Since 1981, the authors have performed computerized tomography (CT)-guided stereotactic aspiration as the initial procedure in 22 patients with colloid cysts; stereotactic aspiration alone was successful in 11 patients (50%). Of the 11 patients in whom aspiration failed, stereotactic endoscopic resection was attempted in three and was successful in one. Seven patients required a craniotomy and microsurgical removal of the cyst performed via a transcortical approach.
The preoperative CT appearance in eight cases of a hypodense or isodense cyst correlated favorably with successful aspiration of the cyst in six patients. A hyperdense appearance on the preoperative CT scan in 14 cases was associated with subtotal aspiration in 13 patients; five required craniotomy for removal. Preoperative magnetic resonance (MR) imaging in eight patients provided excellent anatomical definition of the cyst and its relationship to other structures of the third ventricle, but it was not possible to correlate successful aspiration with cyst appearance on MR images with short or long relaxation time sequences. The authors' 9-year experience suggests that preoperative CT studies accurately determine size, predict viscosity, and help to define a group of colloid cyst patients for whom stereotactic cyst aspiration will likely be successful. Unsuccessful stereotactic aspiration was related to two features: the high viscosity of the intracystic colloid material (nine patients), or deviation of the cyst away from the aspiration needle due to small cyst volume (two patients). Because of its simplicity and low risk, stereotactic surgery can be offered to selected patients as the initial procedure of choice. Craniotomy can be reserved for those whose imaging studies predict failure or for those whose cyst cannot be aspirated.
Relationship between the timing of aneurysm surgery and the development of delayed cerebral ischemia
Authors: Solomon Robert A. , Onesti Stephen T. , Klebanoff Louise 
Published: May 2009

✓ A consecutive series of 145 patients with acute aneurysmal subarachnoid hemorrhage (SAH) were operated on within 7 days of SAH and were prospectively evaluated over a 4-year period to determine if the timing of aneurysm surgery influenced the development of delayed cerebral ischemia. All patients were managed with a standardized policy of urgent surgical clipping and treatment with aggressive prophylactic postoperative volume expansion. Patients with delayed ischemic symptoms were additionally treated with induced hypertension.
Forty-nine patients underwent surgery on Day 0 or 1 (Group 1) post-SAH, 60 patients on Day 2 or 3 (Group 2), and 36 patients on Days 4 through 7 (Group 3). Postoperative delayed cerebral ischemia developed in 16% of (Group 1) patients, in 22% of Group 2 patients, and in 28% of Group 3 patients. Cerebral infarction resulting from delayed cerebral ischemia developed in only 4% of Group 1 patients, 10% of Group 2 patients, and 11 % of Group 3 patients. A bad clinical outcome as a result of delayed cerebral ischemia occurred in one Group 1 patient (2%), two Group 2 patients (3%), and one Group 3 patient (3%). Preoperative grade was not significantly correlated with the incidence or severity of delayed cerebral ischemia at any time interval except that patients in modified Hunt and Hess Grade I or II who underwent surgery on Day 0 or 1 after SAH had no strokes or bad outcomes from delayed cerebral ischemia. This study demonstrates that there is no rationale for delaying aneurysm surgery based on the time interval between SAH and patient evaluation.
Primary angiosarcoma of the central nervous system
Authors: Mena Hernando , Ribas Jorge L. , Enzinger Franz M. , Parisi Joseph E. 
Published: May 2009

✓ Angiosarcoma arising in the central or peripheral nervous system has rarely been reported. Eight patients with primary angiosarcoma of the central nervous system are described here; these included five males and three females ranging in age from 2 weeks to 72 years (mean 38 years). Of the eight neoplasms, six were located in the cerebral hemispheres and one was in the meninges; the site was unknown in the other. All patients underwent surgical resection. Five of the eight patients died, four within 4 months after surgery and one after 30 months. Two of the remaining three patients were 17 and 27 years old at the time of diagnosis and were alive at follow-up review 39 and 102 months after surgery, respectively. One patient was lost to follow-up monitoring.
Microscopically, all eight tumors demonstrated a well-differentiated pattern with irregular vascular channels and intraluminal papillae; in addition, four showed poorly differentiated solid areas. Immunohistochemical staining of neoplastic cells to factor VIII-related antigen and Ulex europaeus agglutinin I was performed in five tumors and was focally positive in four. No correlation could be shown between the histological features and the growth and biological behavior of the tumors.
Differences in critical cerebral blood flow with age in swine
Authors: Harada Jun , Takaku Akira , Endo Shunro , Kuwayama Naoya , Fukuda Osamu 
Published: May 2009

✓ Normal cerebral blood flow (CBF), critical CBF at a flat reading of the electroencephalogram (EEG), and reversibility of the flat EEG after reperfusion were investigated in a total of 59 pigs, including seven newborns (1 to 3 days of age), 38 juveniles (1 month old), and 14 adults (7 months old). The CBF was determined by the hydrogen clearance method; the EEG was recorded continuously and a power spectrum analysis was performed. Cerebral ischemia was produced by occlusion of both common carotid arteries and induction of hypotension (approximately 50 mm Hg). The flat EEG reversibility was investigated for 3 hours after reperfusion. As parameters of brain development, the neuronal density and the time at which the S-100 protein appeared in the brain were examined.
Normal CBF was highest in neonatal pigs and decreased with age. The critical CBF at a flat EEG was lowest in newborn pigs and was elevated with development of the brain. Tolerance against cerebral ischemia was greatest in newborn pigs.
Head-injured patients who talk and deteriorate into coma
Authors: Lobato Ramiro D. , Rivas Juan J. , Gomez Pedro A. , Castañeda Mario , Cañizal José M. , Sarabia Rosario , Cabrera Antonio , Muñoz Maria J. 
Published: May 2009

✓ Of 838 patients with severe head injuries admitted since the introduction of computerized tomography, 211 (25.1%) talked at some time between trauma and subsequent deterioration into coma. Of these 211 patients, 89 (42.2%) had brain contusion/hematoma, 46 (21.8%) an epidural hematoma, 35 (16.6%) a subdural hematoma, and 41 (19.4%) did not show focal mass lesions. Thus, four of every five patients who deteriorated into coma after suffering an apparently nonsevere head injury had a mass lesion potentially requiring surgery; the mass was intracerebral in 52.3% of the cases and extracerebral in 47.6%. Patients aged 20 years or less had a 39% chance of having a nonfocal mass lesion (diffuse brain damage), a 29% chance of having an epidural hematoma, and a 32% chance of having an intradural mass lesion; patients over 40 years had only a 3% chance of having a nonfocal mass lesion, an 18% chance of having an epidural hematoma, and a 79% chance of having a intradural mass lesion.
Sixty-eight (32.2%) patients died and 143 (67.8%) survived. The following were independent outcome predictors (in order of significance): Glasgow Coma Scale score following deterioration into coma, the highest intracranial pressure during the patient's course, the degree of midline shift, the type of intracranial lesion, and the age of the patient. In contrast, the mechanism of injury, the verbal Glasgow Coma Scale score during the lucid interval, and the length of time until deterioration or until operative intervention did not influence the final result.