Focal cerebral hyperemia after focal head injury in humans: a benign phenomenon?

1995 ◽  
Vol 83 (2) ◽  
pp. 277-284 ◽  
Author(s):  
Damianos E. Sakas ◽  
M. Ross Bullock ◽  
James Patterson ◽  
Donald Hadley ◽  
David J. Wyper ◽  
...  
Keyword(s):  
Head Injury ◽  
Mr Imaging ◽  
Computerized Tomography ◽  
Injury Severity ◽  
Single Photon ◽  
Wide Spectrum ◽  
Photon Emission ◽  
Normal Brain ◽  
Content Type ◽  
Fine Print

✓ To assess the relationship between posttraumatic cerebral hyperemia and focal cerebral damage, the authors performed cerebral blood flow mapping studies by single-photon emission computerized tomography (SPECT) in 53 patients within 3 weeks of brain injury. Focal zones of hyperemia were present in 38% of patients. Hyperemia was correlated with clinical features and early computerized tomography (CT) and magnetic resonance (MR) imaging performed within 48 hours of the SPECT study and late CT and MR studies at 3 months. The hyperemia was observed primarily in structurally normal brain tissue (both gray and white matter), as revealed by CT and MR imaging, immediately adjacent to intraparenchymal or extracerebral focal lesions; it persisted for up to 10 days, but was never seen within the edematous pericontusional zones. The percentage of patients in the hyperemic group having brief (< 30 minutes) or no loss of consciousness was significantly higher than in the nonhyperemic group (twice as high, p < 0.05). Other clinical parameters were not significantly more common in the hyperemic group. The mortality of patients with focal hyperemia was lower than that of individuals without it, and the outcome of survivors with hyperemia was slightly better than patients without hyperemia. These results differ from the literature, which suggests that global posttraumatic hyperemia is primarily an acute, malignant phenomenon associated with increased intracranial pressure, profound unconsciousness, and poor outcome. The current results agree with more recent studies which show that posttraumatic hyperemia may occur across a wide spectrum of head injury severity and may be associated with favorable outcome.

Diagnostic value of 201Tl—single-photon emission computerized tomography studies in cases of posterior fossa hemangioblastomas

2001 ◽  
Vol 95 (2) ◽  
pp. 292-297 ◽  
Author(s):  
Takeo Kondo ◽  
Toshihiro Kumabe ◽  
Shin Maruoka ◽  
Takashi Yoshimoto
Keyword(s):  
Computerized Tomography ◽  
Posterior Fossa ◽  
Single Photon ◽  
Photon Emission ◽  
Magnetic Resonance Images ◽  
Thallium 201 ◽  
Homologous Region ◽  
Single Photon Emission ◽  
Content Type ◽  
Fine Print

Object. The 201Tl uptake index was evaluated for its usefulness in formulating a diagnosis of hemangioblastoma. Thallium-201—single-photon emission computerized tomography (SPECT) studies were performed in nine patients harboring hemangioblastomas in the posterior fossa and in five patients (six lesions) with gliomas in the posterior fossa. Methods. The 201Tl uptake index was defined as the ratio of mean counts of isotope per pixel in the tumor to mean counts of isotope per pixel in the homologous region of the healthy brain. The 201Tl uptake indices of the early image (TlE) and that of the delayed image (TlD) were calculated. The isotope retention index (RI) was calculated as (TlE − TlD)/TlE. The TlE was 2.7 ± 0.7 in hemangioblastomas and 2.9 ± 1.7 in gliomas (mean ± standard deviation). The TlD was 1.5 ± 0.4 in hemangioblastomas and 2.4 ± 1.6 in gliomas. There were no significant differences between hemangioblastomas and gliomas when TlEs and TlDs were compared. The isotope RI was 0.43 ± 0.07 in hemangioblastomas and 0.15 ± 0.1 in gliomas, showing a significantly higher RI in hemangioblastomas compared with gliomas (p < 0.01). Conclusions. Thallium-201 washout is significantly faster in hemangioblastomas. Hemangioblastoma is biologically benign, but contains a rich capillary network that forms a hypervascular tumor bed. Variations in its appearance on magnetic resonance images may cause difficulties in the differential diagnosis of hemangioblastoma. Thallium-201 SPECT studies can be used to distinguish hemangioblastomas from gliomas in the posterior fossa.

Reversible ischemia around intracerebral hemorrhage: a single-photon emission computerized tomography study

2002 ◽  
Vol 96 (4) ◽  
pp. 736-741 ◽  
Author(s):  
M. Shahid Siddique ◽  
Helen M. Fernandes ◽  
Thomas D. Wooldridge ◽  
John D. Fenwick ◽  
Piotr Slomka ◽  
...  
Keyword(s):  
Intracerebral Hemorrhage ◽  
Computerized Tomography ◽  
Single Photon ◽  
Photon Emission ◽  
Single Photon Emission ◽  
Large Space ◽  
Content Type ◽  
Ischemic Change ◽  
Late Image ◽  
Fine Print

Object. A zone of perilesional ischemia has been demonstrated around intracerebral hemorrhage (ICH) in numerous experimental models and in human studies. There is potential for perfusion recovery in the zone of perilesional oligemia around ICH. The authors sought to demonstrate, quantify, and study the chronological evolution of perilesional ischemic change in ICH in humans by measuring cerebral blood flow. Methods. Eleven patients with spontaneous supratentorial ICH underwent two technetium-99m hexamethylpropyleneamine oxime single-photon emission computerized tomography (SPECT) scanning, one in the acute stage (within days of ictus) and the other in the late stage (6–9 months postictus). All patients in this study were treated nonsurgically. Methods of SPECT data analysis based on count differences in regions of interest can be difficult to apply to images with large space-occupying lesions such as ICH, because of the distortion of intracranial anatomy, midline shift, and alterations in the three-dimensional (3D) characteristics of the lesion over time (that is, absorption of the hematoma on the later studies). The authors used the following method: the late and early images were registered and aligned to a common 3D orientation and were normalized to maximal counts. The late images were then compared voxel by voxel with the early ones. The region-growing algorithm was used to discern the difference between the two images, outlining voxels in the perihematoma region, with a signal improvement of at least 15% on the late image. Discrete brain regions around the hematoma with at least a 15% improvement in radiotracer uptake (and hence perfusion) in the late images were observed in all cases. The mean volume of brain with a greater than 15% improvement in perfusion between the two studies was 34.8 cm3 (range 7.2–71.3 cm3). These volumes represent regions of the brain that were poorly perfused in the initial studies. This may represent a zone of reversible perilesional oligemia (penumbra) in ICH in humans. Conclusions. This is the first study in which it is documented that some of the perilesional hypoperfused tissue around human ICH regains its perfusion in the long term, leading the authors to suggest that there may be a penumbra in human ICH. Medical or surgical therapeutic interventions could increase the volume of perilesional brain that recovers after the initial insult. The results of this study therefore support the concept that intervention in ICH has the potential to reduce the ultimate neurological deficit and improve outcome.

Functional thalamic depression in a case of reversible central pain due to a spinal intramedullary cyst

1995 ◽  
Vol 83 (1) ◽  
pp. 163-165 ◽  
Author(s):  
Carlo Alberto Pagni ◽  
Sergio Canavero
Keyword(s):  
Spinal Cord ◽  
Computerized Tomography ◽  
Single Photon ◽  
Photon Emission ◽  
Central Pain ◽  
Single Photon Emission ◽  
Content Type ◽  
Surgical Evacuation ◽  
Intramedullary Cyst ◽  
Fine Print

✓ In this report the authors discuss a case of central pain of spinal cord origin due to a spinal thoracic intramedullary cyst. Single-photon emission computerized tomography with technetium-99 hexamethylpropyleneamineoxime showed thalamic hypoperfusion contralateral to the affected leg. Surgical evacuation resulted in total relief of the pain and normalization of the thalamic alteration. The reader can infer from these findings that functional alterations in thalamic processing may be important in the genesis of central pain.

Evaluation of the response of metastatic brain tumors to stereotactic radiosurgery by proton magnetic resonance spectroscopy, 201TlCl single-photon emission computerized tomography, and gadolinium-enhanced magnetic resonance imaging

2004 ◽  
Vol 100 (5) ◽  
pp. 835-841 ◽  
Author(s):  
Teruo Kimura ◽  
Kazuhiro Sako ◽  
Kunio Tanaka ◽  
Takumi Gotoh ◽  
Hiroshi Yoshida ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Brain Tumors ◽  
Mr Imaging ◽  
Stereotactic Radiosurgery ◽  
Mr Spectroscopy ◽  
Single Photon ◽  
Photon Emission ◽  
Metastatic Brain Tumors ◽  
Content Type ◽  
Fine Print

Object. The goal of this study was to investigate the usefulness of proton (1H) magnetic resonance (MR) spectroscopy to evaluate the response of metastatic brain tumors to stereotactic radiosurgery (SRS) in comparison with Gd-enhanced MR imaging and single-photon emission computerized tomography with administration of thallium-201 chloride (201TlCl-SPECT). Methods. Forty patients with a total of 47 metastatic brain tumors were evaluated. The primary lesion was identified in all cases. Stereotactic radiosurgery was effective in 37 lesions. All patients were examined using Gd-enhanced MR imaging before and after SRS. Thalium-201 chloride was administered to 27 patients with 34 tumors and SPECT images were obtained. Proton MR spectroscopy was performed in 36 patients who harbored 43 tumors. On Gd-enhanced MR images, a decrease in the volume of the Gd-enhanced lesion and a change in the enhanced effect in the lesion after treatment were recognized as showing the effectiveness of SRS between 1 and 3 months or more (mean 8.54 ± 3.58 weeks). In 201TlCl-SPECT studies, the ratio of lesion to normal brain decreased from 2 weeks to 2 months (mean 5.03 ± 2.77 weeks) after radiosurgery. On 1H-MR spectroscopy images a high choline (Cho) peak and a lipiddominant (Lip) peak were observed in 25 lesions and a high Cho peak and a lactate-dominant (Lac) peak were observed in 12 lesions before SRS. A decrease in the Cho peak, a disappearance of the Lac peak, and an increase in the Lip peak were observed between 1 week and 1 month (mean 2.76 ± 1.62 weeks) after treatment. Conclusions. Based on histopathological findings obtained at autopsy or at surgery, we assume that a high Cho peak may be observed in viable tumor tissue and a Lip peak in areas of necrosis. The results indicate that 1H-MR spectroscopy is potentially a more sensitive tool in evaluating the response to SRS than 201TlCl-SPECT or Gd-enhanced MR imaging and that it can be used earlier for this purpose than those other imaging methods.

Dual-isotope single-photon emission computerized tomography scanning in patients with glioblastoma multiforme: association with patient survival and histopathological characteristics of tumor after high-dose radiotherapy

1998 ◽  
Vol 89 (1) ◽  
pp. 60-68 ◽  
Author(s):  
Richard B. Schwartz ◽  
B. Leonard Holman ◽  
Joseph F. Polak ◽  
Basem M. Garada ◽  
Marc S. Schwartz ◽  
...  
Keyword(s):  
Survival Rate ◽  
Glioblastoma Multiforme ◽  
Single Photon ◽  
Photon Emission ◽  
High Dose ◽  
Term Survival ◽  
Content Type ◽  
Dual Isotope ◽  
Fine Print

Object. The study was conducted to determine the association between dual-isotope single-photon emission computerized tomography (SPECT) scanning and histopathological findings of tumor recurrence and survival in patients treated with high-dose radiotherapy for glioblastoma multiforme. Methods. Studies in which SPECT with 201Tl and 99mTc-hexamethypropyleneamine oxime (HMPAO) were used were performed 1 day before reoperation in 47 patients with glioblastoma multiforme who had previously been treated by surgery and high-dose radiotherapy. Maximum uptake of 201Tl in the lesion was expressed as a ratio to that in the contralateral scalp, and uptake of 99mTc-HMPAO was expressed as a ratio to that in the cerebellar cortex. Patients were stratified into groups based on the maximum radioisotope uptake values in their tumor beds. The significance of differences in patient gender, histological characteristics of tissue at reoperation, and SPECT uptake group with respect to 1-year survival was elucidated by using the chi-square statistic. Comparisons of patient ages and time to tumor recurrence as functions of 1-year survival were made using the t-test. Survival data at 1 year were presented according to the Kaplan—Meier method, and the significance of potential differences was evaluated using the log-rank method. The effects of different variables (tumor type, time to recurrence, and SPECT grouping) on long-term survival were evaluated using Cox proportional models that controlled for age and gender. All patients in Group I (201Tl ratio < 2 and 99mTc-HMPAO ratio < 0.5) showed radiation changes in their biopsy specimens: they had an 83.3% 1-year survival rate. Group II patients (201T1 ratio < 2 and 99mTc-HMPAO ratio of ≥ 0.5 or 201Tl ratio between 2 and 3.5 regardless of 99mTc-HMPAO ratio) had predominantly infiltrating tumor (66.6%); they had a 29.2% 1-year survival rate. Almost all of the patients in Group III (201Tl ratio > 3.5 and 99mTc-HMPAO ratio ≥ 0.5) had solid tumor (88.2%) and they had a 6.7% 1-year survival rate. Histological data were associated with 1-year survival (p < 0.01); however, SPECT grouping was more closely associated with 1-year survival (p < 0.001) and was the only variable significantly associated with long-term survival (p < 0.005). Conclusions. Dual-isotope SPECT data correlate with histopathological findings made at reoperation and with survival in patients with malignant gliomas after surgical and high-dose radiation therapy.

Early magnetic resonance imaging of brainstem lesions after severe head injury

1998 ◽  
Vol 89 (5) ◽  
pp. 707-712 ◽  
Author(s):  
Raimund Firsching ◽  
Dieter Woischneck ◽  
Michael Diedrich ◽  
Susan Klein ◽  
Andreas Rückert ◽  
...  
Keyword(s):  
Head Injury ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Severe Head Injury ◽  
Auditory Evoked Potentials ◽  
Ct Scanning ◽  
Brainstem Lesion ◽  
Content Type ◽  
Brainstem Lesions ◽  
Fine Print

Object. The availability of magnetic resonance (MR) imaging data obtained in comatose patients after head injury is scarce, because MR imaging is somewhat cumbersome to perform in patients requiring ventilation and because, in the first hours after injury, its relevance is clearly inferior to computerized tomography (CT) scanning. The authors assessed the value of MR imaging in the early postinjury period. Methods. In this prospective study MR imaging was performed in 61 consecutive patients within 7 days after they suffered a severe head injury. An initial CT scan had already been obtained. To understand the clinical significance of the lesions whose morphological appearance was identified with MR imaging, brainstem function was assessed by registration of somatosensory and auditory evoked potentials. Brainstem lesions were visualized in 39 patients (64%). Bilateral pontine lesions proved to be 100% fatal and nonbrainstem lesions carried a mortality rate of 9%. In singular cases circumstances allowed for a clear clinical distinction between primary and secondary brainstem lesions. On MR imaging all lesions were hyper- and hypointense after intervals longer than 2 days. Within shorter intervals (< 2 days) after the injury, primary lesions appeared isointense on MR imaging. In one secondary brainstem lesion there were no traces of blood. Conclusions. Because mean intracranial pressure (ICP) levels in patients without brainstem lesions were similar to those in patients with brainstem lesions, the authors conclude that it was not mainly increased ICP that accounted for the high mortality rates in patients with brainstem lesions. The authors also conclude that brainstem lesions are more frequently found in severe head injury than previously reported in studies based on neuropathological or CT scanning data. Early MR imaging after head injury has a higher predictive value than CT scanning.

Effect of apolipoprotein E genotype on hematoma volume after trauma

2002 ◽  
Vol 96 (1) ◽  
pp. 90-96 ◽  
Author(s):  
Imran Liaquat ◽  
Laurence T. Dunn ◽  
James A. R. Nicoll ◽  
Graham M. Teasdale ◽  
John D. Norrie
Keyword(s):  
Head Injury ◽  
Ct Scan ◽  
Injury Severity ◽  
Univariate Analysis ◽  
Hematoma Volume ◽  
Patient Age ◽  
Content Type ◽  
Head Injured ◽  
Injured Patients ◽  
Fine Print

Object. The apolipoprotein E-ϵ4 (APOE-ϵ4) allele is associated with poor outcome after head injury and spontaneous intracerebral hemorrhage (SICH). The aims of this study were to determine if patients in whom one or more APOE-ϵ4 alleles are present are more likely to sustain intracranial mass lesions after head injury and to determine whether there is an isoform-specific effect on the size of the intracranial hematoma. Methods. The authors performed a computerized volumetric analysis of 142 hematomas visible on computerized tomography (CT) scans obtained in 129 patients. The APOE genotype was determined by subjecting buccal smear samples to polymerase chain reaction and restriction enzyme digestion. Allele frequencies were similar in head-injured patients with and without intracranial hematomas (p = 0.36). Univariate analysis revealed that in those patients with one or more APOE-ϵ4 alleles hematoma volume was greater (cube root—transformed values) than that found in patients without the APOE-ϵ4 allele (3.1 cm compared with 2.5 cm, p = 0.0039). The results of univariate analysis also suggested significant effects of patient age, injury severity (mild, moderate, or severe according to admission Glasgow Coma Scale scores) and hematoma location (extraaxial, intraaxial, or both) on hematoma volume. The mechanism of injury (assault, fall, or other) was marginally associated with hematoma volume (p = 0.052). Time from injury to CT scan, hypoxia, and hypotension had no significant effect on hematoma volume. The results of multiple linear regression analysis showed that the presence of an APOE-ϵ4 allele and an extraaxial hematoma location were independent predictors of hematoma volume, after adjusting for patient age, hours between injury and CT scan, injury severity, and injury mechanism. Conclusions. Larger hematomas were found in head-injured patients with one or more APOE-ϵ4 alleles than in patients without the allele. This may contribute to the poorer outcomes observed in these patients.

Integration of biochemical images of a tumor into frameless stereotaxy achieved using a magnetic resonance imaging/magnetic resonance spectroscopy hybrid data set

2004 ◽  
Vol 101 (2) ◽  
pp. 287-294 ◽  
Author(s):  
Andreas Stadlbauer ◽  
Ewald Moser ◽  
Stephan Gruber ◽  
Christopher Nimsky ◽  
Rudolf Fahlbusch ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Mr Imaging ◽  
Mr Spectroscopy ◽  
Frameless Stereotaxy ◽  
Low Grade ◽  
Normal Brain ◽  
Tumor Infiltration ◽  
Data Set ◽  
Content Type ◽  
Fine Print

Object. It is often difficult to delineate the extent of invasion of high- and low-grade gliomas into normal brain tissue by using conventional T1- and T2-weighted magnetic resonance (MR) imaging. Knowledge of the relationship between the tumor infiltration zone and normal brain, however, is one of the prerequisites for performing as radical a tumor resection as possible. Proton MR spectroscopy allows noninvasive measurements of the concentrations and spatial distributions of brain metabolites and, therefore, may provide biochemical information in vivo, that is useful in distinguishing pathological from normal areas of the brain. The authors have developed a method to use the properties of MR spectroscopy to investigate intraoperatively pathological changes in the spatial distribution of choline (Cho)-containing compounds, total creatine, and N-acetylaspartate (NAA) in brain tumors with the aid of frameless stereotaxy. Methods. Maps of the Cho/NAA ratio were calculated and automatic segmentation of the tumors was performed. Spectroscopic images of the segmented tumor were matched to an anatomical three-dimensional (3D) MR imaging set by applying a fully automated mutual-information algorithm. The resulting 3D MR image can be used subsequently for neurosurgical planning, transfer to a frameless stereotactic system, and display in the navigation microscope during surgery leading to 1H-MR spectroscopy-guided navigation. Conclusions. This method may allow better intraoperative identification of tumor border zones based on metabolic changes due to tumor infiltration.

Diagnosis of root avulsions in traumatic brachial plexus injuries: value of computerized tomography myelography and magnetic resonance imaging

1997 ◽  
Vol 86 (1) ◽  
pp. 69-76 ◽  
Author(s):  
Gustavo Adolpho Carvalho ◽  
Guido Nikkhah ◽  
Cordula Matthies ◽  
Götz Penkert ◽  
Madjid Samii
Keyword(s):  
Mr Imaging ◽  
Brachial Plexus ◽  
Computerized Tomography ◽  
Root Avulsion ◽  
Imaging Studies ◽  
Ct Myelography ◽  
Content Type ◽  
Brachial Plexus Surgery ◽  
Cervical Root ◽  
Fine Print

✓ Surgical management and prognosis of traction injuries of the brachial plexus depend on the accurate diagnosis of root avulsion from the spinal cord. Myelography, computerized tomography (CT) myelography, and recently magnetic resonance (MR) imaging have become the main radiological methods for preoperative diagnosis of cervical root avulsions. Most of the previous studies on the accuracy of CT myelography and MR imaging studies have correlated the radiological findings with the extraspinal surgical findings at brachial plexus surgery. Surgical experience shows that in many cases extraspinal findings diverge from intradural determinations. Consequently, only correlation with the intradural surgical findings will allow assessment of the factual accuracy of CT myelography and MR imaging studies. In a prospective study, 135 cervical roots (C5–8) were evaluated by CT myelography and/or MR imaging and further explored intradurally via a hemilaminectomy. The accuracy of the preoperative CT myelography—based diagnosis in relation to the intraoperative findings was 85%. On the other hand, MR imaging demonstrated an accuracy of only 52%. The most common reasons for false-positive or false-negative findings were: 1) partial rootlet avulsion; 2) intradural fibrosis; and 3) dural cystic lesions. Computerized tomography myelography scans using 1- to 3-mm axial slices prove to be the most reliable method to evaluate preoperatively the presence of complete or partial root avulsion in traumatic brachial plexus injuries. Because extradural judgment of cervical root avulsion can be unreliable, accurate assessment of intraspinal root avulsion enormously simplifies the decision concerning the choice of donor nerves for transplantation and/or neurotization during brachial plexus surgery.

Growing fracture of the skull and the role of computerized tomography

1981 ◽  
Vol 55 (3) ◽  
pp. 470-472 ◽  
Author(s):  
Richard H. Lye ◽  
J. V. Occleshaw ◽  
John Dutton
Keyword(s):  
Head Injury ◽  
Computerized Tomography ◽  
Case History ◽  
Rare Complication ◽  
Leptomeningeal Cyst ◽  
Content Type ◽  
History Of ◽  
Fine Print

✓ Growing fracture of the skull is a rare complication following head injury. The case history of a child with such a fracture, who developed a leptomeningeal cyst, is presented. The unusual features of this case are discussed in the light of previous reports. The usefulness of computerized tomography in obviating the need for more invasive preoperative investigations is demonstrated.

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