bluuebunny/crossref_metadata_2025_split huggingface dataset:
Monitoring of cerebral oxygenation in patients with severe head injuries: brain tissue PO2 versus jugular vein oxygen saturation
Authors: Kiening Karl L. , Unterberg Andreas W. , Bardt Tillman F. , Schneider Gerd-Helge , Lanksch Wolfgang R. 
Published: June 2009

✓ Monitoring of cerebral oxygenation is considered to be of great importance in minimizing secondary hypoxic and ischemic brain damage following severe head injury. Although the threshold for cerebral hypoxia in jugular bulb oximetry (measurement of O2 saturation in the jugular vein (SjvO2)) is generally accepted to be 50% oxygen saturation, a comparable value in brain tissue PO2 (PtiO2) monitoring, a new method for direct assessment of PO2 in the cerebral white matter, has not yet been established. Hence, the purpose of this study was to compare brain PtiO2 with SjvO2 in severely head injured patients during phases of reduced cerebral perfusion pressure (CPP) to define a threshold in brain PtiO2 monitoring. In addition, the safety and data quality of both SjvO2 and brain PtiO2 monitoring were studied.
In 15 patients with severe head injuries, SjvO2 and brain PtiO2 were monitored simultaneously. For brain PtiO2 monitoring a polarographic microcatheter was inserted in the frontal cerebral white matter, whereas for SjvO2 measurements were obtained by using a fiberoptic catheter placed in the jugular bulb. Intracranial pressure was monitored by means of an intraparenchymal catheter. Mean arterial blood pressure, CPP, end-tidal CO2, and arterial oxygen saturation (pulse oximetry) were continuously recorded. All data were simultaneously stored and analyzed using a multimodal computer system. For specific analysis, phases of marked deterioration in systemic blood pressure and consecutive reductions in CPP were investigated.
There were no complications that could be attributed to the PtiO2 catheters, that is, no intracranial bleeding or infection. The “time of good data quality” was 95% in brain PtiO2 compared to 43% in SjvO2; PtiO2 monitoring could be performed twice as long as SjvO2 monitoring. During marked decreases in CPP, SjvO2 and brain PtiO2 correlated closely. A significant second-order regression curve of SjvO2 versus brain PtiO2 (p < 0.01) was plotted. At a threshold of 50% in SjvO2, brain PtiO2 was found to be within the range of 3 to 12 mm Hg, with a regression curve “best fit” value of 8.5 mm Hg. There was a close correlation between CPP and oxygenation parameters (PtiO2 and SjvO2) when CPP fell below a breakpoint of 60 mm Hg, suggesting intact cerebral autoregulation in most patients.
This study demonstrates that monitoring brain PtiO2 is a safe, reliable, and sensitive diagnostic method to follow cerebral oxygenation. In comparison to SjvO2, PtiO2 is more suitable for long-term monitoring. It can be used to minimize episodes of secondary cerebral maloxygenation after severe head injury and may, hopefully, improve the outcome in severely head injured patients.
Clinical significance of diffuse dural enhancement detected by magnetic resonance imaging
Authors: River Yaron , Schwartz Allan , Gomori John M. , Soffer Dov , Siegal Tali 
Published: June 2009

✓ This study was performed to determine the clinical significance of diffuse dural enhancement (DDE) detected by magnetic resonance (MR) imaging and to typify enhancing patterns related to inflammatory or metastatic causes. The authors retrospectively evaluated the clinical, imaging, and laboratory characteristics of 20 consecutive patients with DDE. Those with DDE and an underlying neoplastic disease (13 patients) were compared to 11 consecutive patients with cytological evidence of neoplastic leptomeningeal metastasis evaluated by MR imaging. The DDE was often associated with an underlying malignancy (13 (65%) of 20 patients) but it coexisted with leptomeningeal metastasis in only one patient. Skull metastases were evident in 10 (77%) of 13 patients and cranial nerve palsies in six (46%) of 13. Other causes of DDE were related to cerebrospinal fluid (CSF) leak or shunting (five (25%) of 20), with or without symptoms of intracranial hypotension, and to dural sinus thrombosis and pachymeningitis. Dural biopsies obtained in two patients with DDE showed a narrow rim of granulation-like tissue adherent to the dural surface facing the inner skull table. Magnetic resonance subtraction, diffusion, and perfusion studies revealed unique characteristics in patients with metastatic causes as compared to those with DDE secondary to CSF leak. None of the patients with proven leptomeningeal metastasis had DDE, but four of them presented with focal dural enhancement and two displayed apparent leptomeningeal enhancement.
The findings indicate that DDE is not a radiographic hallmark of leptomeningeal metastasis in spite of the similarities in clinical manifestations (for example, headache and cranial polyneuropathy). Nonetheless, DDE is most frequently associated with metastatic malignancies and particularly with skull metastases and CSF leak. Special MR techniques can discern the underlying cause and elucidate the disparity in the pathophysiological mechanisms leading to DDE.
Surgical treatment of clival chordomas: the transsphenoidal approach revisited
Authors: Maira Giulio , Pallini Roberto , Anile Carmelo , Fernandez Eduardo , Salvinelli Fabrizio , La Rocca Luigi Maria , Rossi Gian Franco 
Published: June 2009

✓ This is a report of 12 cases of clival chordomas that were surgically treated at the Catholic University Medical School, Rome, Italy, over a 7-year period. The study emphasizes the role of the transsphenoidal approach.The study group included seven men and five women whose ages ranged from 26 to 80 years (mean 49.8 years). Diplopia was the most common presenting symptom (eight cases). The tumor involved the upper and middle clivus in five cases, the middle clivus in five, and the lower clivus in two cases. One patient developed spinal metastasis. On histological examination, eight cases proved to be typical chordomas, three cases had a chondroid component, and one case of chordoma had atypical features. Immunohistological staining for vimentin and epithelial membrane antigen was positive in all cases. Follow-up periods ranged from 14 to 86 months (mean 40.2 months). The primary treatment consisted of surgery.Ten patients with chordomas of the upper and middle clivus underwent a total of 13 transsphenoidal procedures. Total tumor removal was achieved in seven cases, subtotal removal in two, and partial removal in one case. In the two cases of lower clival chordomas, total removal was accomplished in one and partial removal in the other. After total removal, no recurrence was noted at 14 to 86 months (mean 37.5 months). In the cases undergoing operation via a transsphenoidal approach, there was zero morbidity and one cerebrospinal fluid fistula that resolved without surgery. The tumor recurred in two patients after subtotal and partial removal, respectively. The authors opted to reoperate in cases of recurrence. Postoperative radiotherapy was administered in only two cases in which further surgery was not indicated because of medical reasons or because such a procedure was contrary to the patient's wishes.When mortality and morbidity rates of this group are compared to those of chordoma patients who were treated with extensive skull-base surgery, the results prompt a reappraisal of the transsphenoidal approach in the treatment of clival chordomas.
Clinical outcomes and radiological instability following decompressive lumbar laminectomy for degenerative spinal stenosis: a comparison of patients undergoing concomitant arthrodesis versus decompression alone
Authors: Fox Mark W. , Onofrio Burton M. , Hanssen Arlen D. 
Published: June 2009

✓ One hundred twenty-four patients with degenerative lumbar stenosis underwent decompression with fusion (32 patients) and without fusion (92 patients) during a 30-month period between 1986 and 1988. Patient-reported satisfaction at a mean follow-up period of 5.8 years (range 4.6–6.8 years) revealed a 79% good or fair outcome and a 21% poor outcome (26 patients). Seven patients (6%) developed lumbar instability, three patients (2%) developed new stenosis at an adjacent unoperated level, and three patients (2%) developed a new disc herniation between 2 and 5 years after surgery. Progressive postoperative spondylolisthesis occurred in 31% of patients with normal preoperative alignment (mean 7.8 mm, range 2–20 mm) and in 73% of patients with preoperative subluxation (mean 5.1 mm, range 2–13 mm) in whom fusion was not attained. Radiological progression did not correlate well with patient-reported outcome.The major conclusions from this study are the following: 1) the majority of patients respond well to this surgery, but complication (22%) and late deterioration (10%) rates are not insignificant; 2) radiological instability is common after decompression for degenerative lumbar spinal stenosis, but this correlates poorly with clinical outcome; 3) there are no definitive clinical or radiological factors that preoperatively predict patients at risk for a poor outcome; 4) postoperative radiological instability is more likely to occur when the following criteria are present: preoperative spondylolisthesis, abnormal motion detected on preoperative dynamic imaging, decompression occuring across a minimally degenerated L-4 or a markedly degenerated L-3 disc; and when a radical and extensive decompression greater than one level is planned; and 5) the group at greatest risk for a poor outcome consists of those patients with normal preoperative alignment who do not suffer slippage following surgery.
Long-term follow-up review of suspension laminotomy for cervical compression myelopathy
Authors: Inoue Hidenori , Ohmori Kazuo , Ishida Yoshihiro , Suzuki Kazuhiro , Takatsu Tetsuro 
Published: June 2009

This study compared the long-term outcome of cervical spondylotic myelopathy (CSM) with that of the ossification of the posterior longitudinal ligament of the cervical spine (OPLL) after suspension laminotomy, which was developed in the authors' clinic. Seventy-six patients who received follow-up care for more than 5 years were available for analysis. The duration of the follow-up period averaged 97.8 months (range 61–160 months). Radiological and neurological analyses were performed in these 76 patients (50 with CSM and 26 with OPLL). There were no differences in sex, age, follow-up period, and preoperative neurological status between the two groups.
In the quantitative study of the dural configuration, 43 patients (86%) with CSM and 17 patients (65.4%) with OPLL attained complete decompression 1 month after surgery. At long-term follow-up review, complete decompression was maintained in 42 patients (84%) with CSM but in only seven patients (26.9%) with OPLL. The neurological evaluation improved markedly at early follow up in both groups but declined insignificantly at the last follow-up review, particularly in the OPLL group. Of 12 patients (24%) with CSM and 10 patients (38.5%) with OPLL whose neurological recovery grades later deteriorated, four (8%) with CSM and nine (34.6%) with OPLL demonstrated reconstriction causing spinal cord compression at long-term follow-up review. For the remaining eight patients (16%) with CSM, who were older than 70 years on average at last follow-up review, no radiological explanation was found. These long-term results indicate that OPLL does not resolve as well as CSM after suspension laminotomy; they both may have late deterioration due to reconstriction that occurs occasionally in CSM and frequently in OPLL.
Magnetic resonance imaging for the evaluation of patients with occult cervical spine injury
Authors: Benzel Edward C. , Hart Blaine L. , Ball Perry A. , Baldwin Nevan G. , Orrison William W. , Espinosa Mary C. 
Published: June 2009

✓ Because it is often difficult to diagnose accurately the structurally intact cervical spine after acute trauma, a series of patients was evaluated with magnetic resonance (MR) imaging to assess its efficacy for the evaluation and clearance of the cervical spine in a trauma victim in the early posttrauma period. Ultralow-field MR imaging was used to evaluate 174 posttraumatic patients in whom physical findings indicated the potential for spine injury or minor radiographic findings indicated injury. This series includes only those patients who did not appear to harbor disruption of spinal integrity on the basis of a routine x-ray film. None had clinically obvious injury.
Of the 174 patients, 62 (36%) had soft-tissue abnormalities identified by MR imaging, including disc interspace disruption in 27 patients (four with ventral and dorsal ligamentous injury, three with ventral ligamentous injury alone, 18 with dorsal ligamentous injury alone, and two without ventral or dorsal ligamentous injury). Isolated ligamentous injury was observed in 35 patients (eight with ventral and dorsal ligamentous injury, five with ventral ligamentous injury alone, and 22 with dorsal ligamentous injury alone). One patient underwent a surgical fusion procedure, 35 patients (including the one treated surgically) were placed in a cervical collar for at least 1 month, and 27 patients were placed in a thermoplastic Minerva jacket for at least 2 months. All had a satisfactory outcome without evidence of instability.
The T2-weighted sagittal images were most useful in defining acute soft-tissue injury; axial images were of minimal assistance. Posttraumatic soft-tissue cervical spine injuries and disc herniations (most likely preexisting the trauma) are more common than expected. A negative MR image should be considered as confirmation of a negative or “cleared” subaxial cervical spine. Diagnostic and patient management algorithms may be appropriately tailored by this information. Thus, MR imaging is useful for early acute posttrauma assessment in a very select group of patients.
Decompressive craniectomy in a rat model of “malignant” cerebral hemispheric stroke: experimental support for an aggressive therapeutic approach
Authors: Doerfler Arnd , Forsting Michael , Reith Wolfgang , Staff Christian , Heiland Sabine , Schäbitz Wolf-Rüdiger , von Kummer Rüdiger , Hacke Werner , Sartor Klaus 
Published: June 2009

✓ Acute ischemia in the complete territory of the carotid artery may lead to massive cerebral edema with raised intracranial pressure and progression to coma and death due to uncal, cingulate, or tonsillar herniation. Although clinical data suggest that patients benefit from undergoing decompressive surgery for acute ischemia, little data about the effect of this procedure on experimental ischemia are available. In this article the authors present results of an experimental study on the effects of decompressive craniectomy performed at various time points after endovascular middle cerebral artery (MCA) occlusion in rats.
Focal cerebral ischemia was induced in 68 rats using an endovascular occlusion technique focused on the MCA. Decompressive cranioectomy was performed in 48 animals (in groups of 12 rats each) 4, 12, 24, or 36 hours after vessel occlusion. Twenty animals (control group) were not treated by decompressive craniectomy. The authors used the infarct volume and neurological performance at Day 7 as study endpoints.
Although the mortality rate in the untreated group was 35%, none of the animals treated by decompressive craniectomy died (mortality 0%). Neurological behavior was significantly better in all animals treated by decompressive craniectomy, regardless of whether they were treated early or late. Neurological behavior and infarction size were significantly better in animals treated very early by decompressive craniectomy (4 hours) after endovascular MCA occlusion (p < 0.01); surgery performed at later time points did not significantly reduce infarction size.
The results suggest that use of decompressive craniectomy in treating cerebral ischemia reduces mortality and significantly improves outcome. If performed early after vessel occlusion, it also significantly reduces infarction size. By performing decompressive craniectomy neurosurgeons will play a major role in the management of stroke patients.
Attenuation of acute and chronic damage following traumatic brain injury in copper, zinc—superoxide dismutase transgenic mice
Authors: Mikawa Shigeki , Kinouchi Hiroyuki , Kamii Hideyuki , Gobbel Glenn T. , Chen Sylvia F. , Carlson Elaine , Epstein Charles J. , Chan Pak H. 
Published: June 2009

✓ To elucidate the role of oxygen-derived free radicals and superoxide dismutase in traumatic brain injury (TBI), blood-brain barrier (BBB) permeability, brain edema, behavioral function, and necrotic cavity volume (CV) were evaluated after TBI using nontransgenic (nTg) mice and heterozygous and homozygous transgenic (Tg) mice with a 1.5- (Tg1.5x), 3.1- (Tg3.1x) and five- (Tg5x) fold increase in human copper, zinc—superoxide dismutase (CuZn-SOD) activity.
Traumatic brain injury was produced by the weight-drop method. Evans blue dye leakage 4 hours after injury was attenuated in a CuZn-SOD dose-dependent manner with decreases of 18.6%, 40.9%, and 48.8%, in the Tg1.5x, Tg3.1x, and Tg5x groups, respectively. The water content 6 hours after injury in the Tg3.1x (79.64%) and Tg5x (79.45%) groups was significantly lower than in nTg mice (81.37%). There was an initial decrease in body weight and in motor performance, as measured by beam walk and beam balance tasks undertaken 1 day after TBI. However, the average reduction in beam balance and beam walk performance deficits and changes in body weight postinjury were significantly ameliorated in Tg mice. The CV was significantly smaller in Tg mice than in nTg mice (p < 0.01). These results indicate that superoxide radicals play a deleterious role following TBI. Furthermore, Tg mice provide a useful model for demonstrating the beneficial role of an antioxidant enzyme in TBI without the confounding effect of pharmacokinetics, toxicity, and BBB permeability associated with exogenous agents.
Focal hyperexpression of hemeoxygenase-1 protein and messenger RNA in rat brain caused by cellular stress following subarachnoid injections of lysed blood
Authors: Matz Paul G. , Massa Stephen M. , Weinstein Philip R. , Turner Christopher , Panter S. Scott , Sharp Frank R. 
Published: June 2009

✓ Induction of the hemeoxygenase-1 (ho-1) stress gene is of importance for rapid heme metabolism and protection against oxidative injuryin vitroandin vivo. Althoughho-1expression is observed in glia following exposure to whole blood and oxyhemoglobin, expression is mild, and other stress genes are not induced simultaneously in this setting. Hemeoxygenase-1 can be induced by several other physiological stresses in addition to heme. In the brain,ho-1induction has been observed in the penumbra following focal cerebral ischemia. Because lysed blood is a spasmogen, the authors studied focal hyperexpression of theho-1gene after injection of lysed blood, whole blood, or saline into the cisterna magna of adult rats. Immunocytochemical analysis of HO-1 was performed at 1, 2, 3, and 4 days after the injections. Because the 70-kD inducible heat shock protein (HSP70) is induced by cellular stress, alternate sections were immunostained for HSP70 to assess whether focal hyperexpression was a stress phenomenon. An oligonucleotide probe was also used forin situhybridization to demonstrate that ho-1 messenger (m)RNA was present.Focal HO-1 immunostained areas were observed after lysed blood injection only and were located mainly in the basal cortex and cerebellar hemisphere, although focal hyperexpression was also found in many other regions. The intensity of staining and the number of regions were maximum at 1 day. Double-labeled immunofluorescence revealed that many HO-1—immunoreactive cells were microglia. The HSP70 immunostaining of adjacent sections from the same animals demonstrated focal regions of immunoreactivity whose topography corresponded exactly with the topography of the HO-1—immunostained areas. Conventional histology in regions of HO-1 hyperexpression was often normal.In situhybridization using the same oligonucleotide demonstrated that ho-1 mRNA was induced in focal areas of forebrain and in large regions of cerebellum within 6 hours of injection.These results demonstrate that focal hyperexpression of theho-1stress gene occurs after lysed blood injection and appears to be an indicator of cellular stress and injury in regions in which infarction does not occur. These results also suggest that cellular injury that occurs after injection of lysed blood may go undetected using conventional histology. Although direct heme metabolism was not investigated, our results indicate that rapid metabolism of heme, both intracellular and extracellular, may prove to be beneficial after subarachnoid hemorrhage.
Effects of oxyhemoglobin on local and propagated vasodilatory responses induced by adenosine, adenosine diphosphate, and adenosine triphosphate in rat cerebral arterioles
Authors: Kajita Yasukazu , Dietrich Hans H. , Dacey Ralph G. 
Published: June 2009

✓ After subarachnoid hemorrhage (SAH), cerebral arteries display impaired vasomotor control, resulting in decreased regional cerebral blood flow. Recently, propagation of vasomotor responses has been recognized as an important regulatory mechanism in microcirculation. In this study, the authors tested the hypothesis that oxyhemoglobin (OxyHb) inhibits the vasodilatory effect of chemical mediators such as adenosine and adenine nucleotides at a local and/or propagated site.Penetrating intracerebral arterioles were surgically isolated from the middle cerebral arteries of rat brains, cannulated, and observed videomicroscopically in an organ bath under an inverted microscope. The effects of 10−5M OxyHb on vasoactive responses to adenosine, adenosine diphosphate (ADP), and adenosine triphosphate (ATP) were examined. The drugs were extraluminally applied either to the bath (10−10−10−3M) or, using pressure microejection (pipette concentration 10−2M), locally.The ATP and ADP initially constricted and then significantly dilated the vessels after both extraluminal application and microapplication. Furthermore, local microstimulation by these drugs produced conducted vasodilation. Adenosine elicited significant vasodilation after both extraluminal and local stimulation. Again, conducted vasodilation was observed. The vasomotor responses that were induced by a maximum local stimulation corresponded in magnitude to those observed at bath concentrations of 10−5to 10−4M of the same drug.Pretreatment with OxyHb constricted arterioles to an average of 87% of control and blunted extraluminally induced dilation at low concentrations (10−10−10−8) of ATP and ADP, but did not affect vasodilation induced by 10−4M or greater concentrations of ATP, ADP, or adenosine. Although the local response to local microstimulation was unaltered, propagated vasodilation as a response to ATP, ADP, and adenosine was significantly attenuated by OxyHb.These findings indicate that vasodilatory propagation plays an important role in the regulation of brain microcirculation and that its impairment by OxyHb could, in part, explain the cerebral hypoperfusion that is observed after SAH.
Septic cavernous sinus thrombosis following transsphenoidal craniotomy
Authors: Sadun Federico , Feldon Steven E. , Weiss Martin H. , Krieger Mark D. 
Published: June 2009

✓ The authors present a case of late-onset cavernous sinus thrombosis in a 74-year-old man who had undergone transsphenoidal craniotomy for a pituitary macroadenoma 9 weeks previously. The patient developed headache, rapidly progressive ophthalmoplegia, and signs of orbital congestion. After 2 days of ineffective broad spectrum antibiotic therapy he underwent a second transsphenoidal craniotomy for abscess drainage. Intraoperative cultures grew 4+ nonhemolytic Streptococcus, 4+ Staphylococcus coagulase negative, and 4+ Haemophilus influenzae. The patient was maintained on intravenous antibiotic therapy for the following 6 weeks, resulting in a complete clinical recovery.
To the authors' knowledge, this is the first report of a septic cavernous sinus thrombosis following a transsphenoidal craniotomy.