Types Of Intracranial Lesions Research Articles

Investigation of fatal traumatic head injuries.

Traumatic head injuries (THIs) are one of the major causes of death in forensic cases. The aim of this study was to investigate the characteristics of patients with fatal THIs. In this study, a total of 311 patients with fatal THIs, who underwent postmortem examinations and/or autopsies, were retrospectively analyzed. Cases were evaluated based on sex, age group, incident origin, cause of the incident, presence of skull fracture, type of fractured bone (if any), fracture localization and pattern, presence and type of intracranial lesion (if any), and cause of death. Out of the patients, 242 (77.8%) were male and 69 (22.2%) were female. Accidents accounted for 235 (75.6%) of the incidents, with in-vehicle traffic accidents causing 117 (37.6%). In 221 cases (71.1%), intracranial lesions and skull fractures were observed together. The most common fractures were base fractures (171 cases) and temporal bone fractures (153 cases). The rate of intracranial hemorrhage was lower in the adult age group (69.7%) compared to the older age group (92.6%). The results obtained in this study indicate that the cause of the incident, type of fracture, presence of skull base fracture, and multiple skull fractures increase the likelihood of fatalities. The occurrence of skull fractures reduces intracranial pressure, thereby decreasing the incidence of intracranial lesions. The development and effective enforcement of road traffic safety policies and regulations will reduce the incidence of fatalities.

Dedicated neuroimaging analysis in children with primary headaches: prevalence of lesions and a comparison between patients with and without migraines

BackgroundThis study evaluated the prevalence and types of intracranial lesions through dedicated imaging analysis of primary headaches in children and compared them between patients with and without migraine.MethodsThis study included 190 children diagnosed with primary headache who underwent neuroimaging, including brain computed tomography (CT), CT angiography (CTA), and brain magnetic resonance imaging (MRI). All patients with primary headaches was divided into two groups, namely, the migraine and non-migraine groups, on the basis of data from electronic medical records. Clinical characteristics and imaging findings were evaluated and compared between the two groups.ResultsPatients with migraine were old and had a longer period from symptom onset to diagnosis. CT was normal in 71 of 95 patients, whereas 7 of 29 patients who underwent CTA had vascular lesions; the migraine group (n = 6/20, [30%]) had higher incidence of vascular lesions than the non-migraine group (n = 1/9, [11.1%]); however, there was no statistically significant difference (p = 0.382). Furthermore, 57.5% (61/106) of children showed normal brain MRI. The most common brain MRI finding was dilated perivascular space (n = 18, [16.8%]). Most perivascular spaces were located in the basal ganglia (n = 72, [75.8%]) and were in linear patterns (n = 58, [63.0%]). There was no statistically significant difference between the two groups.ConclusionA low prevalence of significant abnormalities was found in children with primary headaches. Dilated perivascular space was the most common finding in both groups on MRI. CTA showed more vascular lesions in the migraine group than in the non-migraine group. Therefore, further evaluations are needed to reveal the relationship between vascular lesions or dilated perivascular space and pediatric primary headaches.

HYPERGLYCEMIA AS A PREDICTOR OF OUTCOME IN PAEDIATRIC SEVERE TRAUMATIC BRAIN INJURY PATIENTS UNDERWENT SURGERY: A SINGLE CENTER EXPERIENCE FROM EASTERN INDONESIA FROM 2017-2022.

The aim: Traumatic Brain Injury (TBI) remains a significant health burden worldwide. This study aimed to describe, determine and recommendation concerning the impact of hyperglycemia on pediatric TBI. Materials and methods: Paediatric trauma patients with severe TBI event were identified and admitted to our Dr. Soetomo General Hospital, Surabaya, the regional Trauma Center of East Java, Indonesia between calendar year of 2017 and 2022. Our institutions trauma database was utilized to select the patient included in this study. Patients with GCS ≤ 8 who underwent neurosurgical interventions were included to the study. Neurosurgical interventions are craniotomy for clot evacuation and decompressive craniectomy. We excluded patients with GCS > 8 and/or treated with conservative therapy (no surgery needed). Data collected for analysis as independent variables included patient age, admission GCS score and admission serum glucose score, mechanism of injury, type of intracranial lesion and type of surgery. Outcome of the patients included was examined at discharge which sub-grouped by Glasgow Outcomes Scale (GOS) score. Independent variables were entered into the logistic model in a stepwise fashion with a significant cutoff of p< 0,05. Results: Patients with worse neurological outcomes (GOS score 1-2) had a mean serum glucose value of over 200 mg/dL. Patients who died (GOS score of 1) had higher mean admission glucose values (226.44 ± 62,00) than the patients who had survived with a GOS score of 3 (139.80 ± 10.87), 4 (87), or 5 (134). Patients who resulted in a vegetative state (GOS score of 2) had higher mean admission serum glucose values than patients who were discharged with a GOS score of 5 (205.14 ± 36.17 vs. 134; p = 0.003). Conclusions: Hyperglycaemia in pediatric TBI patients that underwent neurosurgical intervention is associated with worse outcomes, even mortality. We believe that prospective evaluation of glucose normalization in the context of acute management of pediatric head injuries is both appropriate and necessary for the next study.

The coexistence of anterior communicating artery aneurysm and meningioma: A literature review and illustrative case.

Anterior communicating artery (Acom) aneurysm has an association with many types of intracranial lesions. However, its association with meningioma can be challenging, which is not well addressed in the literature. Herein, we described a literature review focused on the association between Acom aneurysm and meningioma, explicitly highlighting the spatial presence between these two pathologies. We analyzed the literature according to that association with particular emphasis on location-based challenges. Furthermore, we present an illustrative case of surgically treating both lesions in one surgery utilizing the same approach. A Medline database search was conducted by the following combined formula: (Meningioma [Title/ Abstract]) AND (Aneurysm [Title/Abstract]) AND (((Anterior communicating artery [Title/Abstract]) OR (Acom [Title/Abstract])) OR Acomm [Title/Abstract]))). Additional resources were added after screening the references of the included papers. Nine patients with coexistence of Acom aneurysm and meningioma were found in the literature. The coexistence of both pathologies was found in seven females and two males. The presence of an aneurysm was found to be solitary in 66.67% (n = 6/9). Furthermore, meningioma was found to be an isolated lesion in all included cases, and in 22.2% (n = 2/9), they were located ipsilaterally. The location of the meningioma to the aneurysm seems to be in proximity. Acom aneurysm can coexist with intracranial meningioma; this association can be spatially related intracranially. Such coexistence entails a variety of nuances and challenges that neurosurgeons encounter during the management of these complex lesions.

High Incidence of Hippocampal Abnormalities in Pediatric Patients with Congenital Cytomegalovirus Infection.

Background  Congenital cytomegalovirus (CMV) infection exhibits polymicrogyria, intracranial calcification, white matter lesions, and several types of intracranial lesions on magnetic resonance imaging (MRI), in addition to various developmental disorders and epilepsies. However, little is known on the presence of hippocampal abnormality in this affliction. The aim of this study is to clarify the incidence of hippocampal abnormality in congenital CMV infection. Methods  Seventeen children diagnosed as having congenital CMV infection along with 17 age-matched pediatric controls were retrospectively evaluated by brain MRI and clinical review. The measurement data were obtained from conventional coronal sections in this retrospective study. Hippocampal malrotation (HIMAL) was defined as a hippocampal diameter ratio (i.e., the ratio of the height and width of the hippocampus) of >0.92. Results  Hippocampal diameter ratios were significantly higher in the congenital CMV infection group (0.99 [range: 0.70–1.58] on the right side and 0.85 [range: 0.66–1.39] on the left side) than in controls (0.71 [range: 0.58–0.91] and 0.70 [range: 0.50–1.00], respectively). HIMAL was present in 17 of 34 hippocampi (50%) in the congenital CMV infection group and 1 of 34 hippocampi (2.9%) in controls. No correlations were detected between HIMAL and intelligence quotient/developmental quotient or the occurrences of autism spectrum disorder or epilepsy. Conclusion  This study is the first to demonstrate the incidence of hippocampal abnormality to be significantly higher in congenital CMV infection patients than in age-matched controls. Further study is necessary to clarify the associations of HIMAL with other clinical and developmental features.

Cognitive Function Outcomes of Post-operative Mild to Moderate Traumatic Brain Injury using Combination of Mini-mental State Examination, Digit Span, and Constructional Praxis

BACKGROUND: Progress has been made in developing systems of care that strives to minimize traumatic brain injury (TBI)-related morbidity and mortality. As the TBI survivors, one’s might be experienced cognitive function disorders that affect their quality of life.&#x0D; AIM: We sought to investigate the changes of cognitive function in patients with mild or moderate TBI.&#x0D; METHODS: This was a prospective study on 80 patients with mild and moderate TBI who had undergone surgery; 79 patients included in the study and one patient excluded due to incompletion of cognitive tasks. We assessed the cognitive function using a combination of mini-mental state examination (MMSE), digit span (DS), and constructional praxis (CP) tests. The correlations between clinical variables and neuropsychological tests were analyzed.&#x0D; RESULTS: In this study, majority of the patients were male (77.2%) with the mean of age 28.4 years, ranging from 15 to 74 years, predominantly was a young adult (15–20 years, 32.9%). In this series, majority of the patients had moderate TBI (69.6%). Most of the patients (55.7%) had 12 or more education years. MMSE examination revealed that 6.3% and 2.5% of patients had mild- and moderate-cognitive disturbances, respectively, significantly correlated with age (p = 0.049) and educational level (p = 0.008). From DS tests, 13.9% patients had attention disorders and significantly correlated with age (p = 0.015), educational level (p = 0.000), and the severity of TBI (p = 0.018). From CP tests, 24.1% and 5.1% had mild- and moderate-disturbances, respectively, significantly correlated with the severity of TBI (p = 0.025) and the type of intracranial lesion (p = 0.009).&#x0D; CONCLUSIONS: We found (using a combination of MMP, DS, and CP test) cognitive impairment more frequently in patients with moderate TBI, older age, and low education level, hence, emphasized the importance of holistic neuropsychological assessments and neurological rehabilitation for adequate management of patients with TBI.

Neurostereologic Lesion Volumes and Spreading Depolarizations in Severe Traumatic Brain Injury Patients: A Pilot Study.

Spreading depolarizations (SDs) occur in 50-60% of patients after surgical treatment of severe traumatic brain injury (TBI) and are independently associated with unfavorable outcomes. Here we performed a pilot study to examine the relationship between SDs and various types of intracranial lesions, progression of parenchymal damage, and outcomes. In a multicenter study, fifty patients (76% male; median age 40) were monitored for SD by continuous electrocorticography (ECoG; median duration 79h) following surgical treatment of severe TBI. Volumes of hemorrhage and parenchymal damage were estimated using unbiased stereologic assessment of preoperative, postoperative, and post-ECoG serial computed tomography (CT) studies. Neurologic outcomes were assessed at 6months by the Glasgow Outcome Scale-Extended. Preoperative volumes of subdural and subarachnoid hemorrhage, but not parenchymal damage, were significantly associated with the occurrence of SDs (P's < 0.05). Parenchymal damage increased significantly (median 34ml [Interquartile range (IQR) - 2, 74]) over 7 (5, 8) days from preoperative to post-ECoG CT studies. Patients with and without SDs did not differ in extent of parenchymal damage increase [47ml (3, 101) vs. 30ml (- 2, 50), P = 0.27], but those exhibiting the isoelectric subtype of SDs had greater initial parenchymal damage and greater increases than other patients (P's < 0.05). Patients with temporal clusters of SDs (≥ 3 in 2h; n = 10 patients), which included those with isoelectric SDs, had worse outcomes than those without clusters (P = 0.03), and parenchymal damage expansion also correlated with worse outcomes (P = 0.01). In multivariate regression with imputation, both clusters and lesion expansion were significant outcome predictors. These results suggest that subarachnoid and subdural blood are important primary injury factors in provoking SDs and that clustered SDs and parenchymal lesion expansion contribute independently to worse patient outcomes. These results warrant future prospective studies using detailed quantification of TBI lesion types to better understand the relationship between anatomic and physiologic measures of secondary injury.

Associated intracranial lesions: meningioma and anterior communicating aneurysm

Abstract Asymptomatic associated intracranial lesions are more frequently diagnosed with the utilization of high-resolution imaging. The occurrence of brain tumors together with intracranial aneurysms are a very rare situation. This coexistence is still a diagnostic and therapeutic challenge as no consensus concerning imaging that may cover both type of intracranial lesion was established. We report a case of a 62 years old patient with a meningioma and aneurysm treated in one session with good outcome.

Routine screening by brain magnetic resonance imaging is not indicated in every girl with onset of puberty between the ages of 6 and 8 years.

It is still controversial whether all girls with central precocious puberty (CPP) should undergo brain magnetic resonance imaging (MRI) for unveiling intracranial pathology. The objectives of the study were to determine the prevalence and type of intracranial lesions in otherwise normal girls with central precocious puberty (idiopathic CPP) and to identify the clinical and biochemical predictors of brain abnormalities. This was a retrospective study conducted at the Endocrine Unit of "Bambino Gesù" Children's Hospital (Rome, Italy) from 1990 to 2012. One hundred eighty-two girls were consecutively diagnosed with CPP. All girls underwent a thorough endocrine assessment and brain MRI with a detailed examination of the hypothalamic-pituitary area. None of them had a history of neurological diseases, endocrine disorders, neurofibromatosis or other genetic syndromes, or previous hormonal therapies. Prevalence of brain abnormalities at MRI scan was measured. Brain MRI showed no alteration in 157 (86%), incidentalomas of the hypothalamic-pituitary area unrelated to CPP in 19 (11%), and hamartomas in six girls (3%). Girls with hamartomas were younger than 6 years and had significantly higher mean baseline and stimulated LH values (P < .001), LH to FSH ratio (P < .001), serum 17β-estradiol levels (P < .001), and uterine length (P < .05). However, all the parameters overlapped extensively in girls with or without cerebral alterations. Our data cast doubt on the need of routine screening by brain MRI in girls with idiopathic CPP older than 6 years. Evidence-based criteria to drive clinical decision making about the use of MRI are lacking.

Surgery for Bilateral Large Intracranial Traumatic Hematomas: Evacuation in a Single Session

ObjectiveManagement guidelines for single intracranial hematomas have been established, but the optimal management of multiple hematomas has little known. We present bilateral traumatic supratentorial hematomas that each has enough volume to be evacuated and discuss how to operate effectively it in a single anesthesia.MethodsIn total, 203 patients underwent evacuation and/or decompressive craniectomies for acute intracranial hematomas over 5 years. Among them, only eight cases (3.9%) underwent operations for bilateral intracranial hematomas in a single session. Injury mechanism, initial Glasgow Coma Scale score, types of intracranial lesions, surgical methods, and Glasgow outcome scale were evaluated.ResultsThe most common injury mechanism was a fall (four cases). The types of intracranial lesions were epidural hematoma (EDH)/intracerebral hematoma (ICH) in five, EDH/EDH in one, EDH/subdural hematoma (SDH) in one, and ICH/SDH in one. All cases except one had an EDH. The EDH was addressed first in all cases. Then, the evacuation of the ICH was performed through a small craniotomy or burr hole. All patients except one survived.ConclusionBilateral intracranial hematomas that should be removed in a single-session operation are rare. Epidural hematomas almost always occur in these cases and should be removed first to prevent the hematoma from growing during the surgery. Then, the other hematoma, contralateral to the EDH, can be evacuated with a small craniotomy.

Is Prehospital Endotracheal Intubation Associated with Improved Outcomes In Isolated Severe Head Injury? A Matched Cohort Analysis

Prehospital endotracheal intubation (ETI) following traumatic brain injury in urban settings is controversial. Studies investigating admission arterial blood gas (ABG) patterns in these instances are scant. Outcomes in patients subjected to divergent prehospital airway management options following severe head injury were studied. This was a retrospective propensity-matched study in patients with isolated TBI (head Abbreviated Injury Scale (AIS) ≥ 3) and Glasgow Coma Scale (GCS) score of ≤ 8 admitted to a Level 1 urban trauma center from January 1, 2003 through October 31, 2011. Cases that had prehospital ETI were compared to controls subjected to oxygen by mask in a one to three ratio for demographics, mechanism of injury, tachycardia/hypotension, Injury Severity Score, type of intracranial lesion, and all major surgical interventions. Primary outcome was mortality and secondary outcomes included admission gas profile, in-hospital morbidity, ICU length of stay (ICU LOS) and hospital length of stay (HLOS). Cases (n = 55) and controls (n = 165) had statistically similar prehospital and in-hospital variables after propensity matching. Mortality was significantly higher for the ETI group (69.1% vs 55.2% respectively, P = .011). There was no difference in pH, base deficit, and pCO2 on admission blood gases; however the ETI group had significantly lower pO2 (187 (SD = 14) vs 213 (SD = 13), P = .034). There was a significantly increased incidence of septic shock in the ETI group. Patients subjected to prehospital ETI had a longer HLOS and ICU LOS. In isolated severe traumatic brain injury, prehospital endotracheal intubation was associated with significantly higher adjusted mortality rate and worsened admission oxygenation. Further prospective validation of these findings is warranted.

Fluorescence-guided surgery for brain tumors.

5-aminolevulinic acid-induced protoporphyrin IX fluorescence was authorized in the EU for visualization of tumor tissue during surgery for WHO grade III and IV gliomas in 2007. It facilitates tumor identification and doubles the number of gross total resections that can be achieved in these tumors. The growing acceptance of fluorescence-guided surgery in malignant gliomas brings forward a substantial yield of data on many types of intracranial lesions. The following review summarizes the main findings of these publications and illustrates the limitations, caveats and future perspectives of 5-aminolevulinic acid-induced fluorescence in malignant glioma as well as in other brain neoplasms.

Role of repeat CT scans in the management of traumatic brain injury

BackgroundIn trauma practice, there are no guidelines on the necessity or value of repeat CT scan. The purpose of the present study was to determine the role of serial CTs in demonstrating changes in intracranial lesions and the influence on management. MethodsIn this study, 201 patients of traumatic brain injury were followed with serial CT scans for a maximum of up to 5 scans. The presence of different types of intracranial lesions at each CT scan as well as the evolution of lesions was recorded. The development of new lesions was noted. The management decisions at the time of each CT was detailed. ResultsProgression of lesion was seen most often in patients with mixed lesions (21.8%). New lesions were seen in 5.5% of patients at CT-2 and in 5.8% at CT-3. Out of total 201 patients, 47 (23%) had change in management. 26 (55%) decisions of change in management were based upon clinical deterioration and 21 (45%) upon radiological changes only. A higher incidence of surgical intervention was seen in patients who had the first CT scan within 6 h of initial trauma. However, a few patients in whom the first CT scan was 6 h after trauma as well as some patients in whom CT scan was repeated as a routine without any clinical deterioration also had a change in their management. ConclusionsRepeat CT scans resulted in management changes even in patients with no clinical deterioration and thus may be of value in detecting changes at an early stage.

A Case of Adipsic Hypernatremia Associated with Anomalous Corpus Callosum in Adult with Mental Retardation

Adipsic hypernatremia cause chronic hyperosmolality and hypernatremia through a combination of impaired thirst and osmotically stimulated antidiuretic hormone secretion. This syndrome can be grouped together as disorders of osmoreceptor dysfunc tion due to the various degrees of osmoreceptor destruction related with different types of intracranial lesions around the anterior hypothalamus, consistent with the location of primary osmoreceptor cells. Adipsic hypernatremia, associated with developmental disorder of corpus callosum, is very rare. Most cases are diagnosed at infancy and early childhood; the replacement of desmopressin is necessary. Herein, we report adipsic hypernatremia associated with anomalous corpus callosum in adult with mental retardation; they were treated with only free water without desmopressin. (Endocrinol Metab 27:232-236, 2012)

Epileptic seizures in neurofibromatosis type 1 are related to intracranial tumors but not to neurofibromatosis bright objects

Objective To investigate the relationship between intracranial lesions and epileptic seizures in neurofibromatosis type 1 (NF1) patients. Background NF1 is one of the most common autosomal dominant neurocutaneous disorders, and epilepsy is more prevalent in NF1 patients than in the general population. Epileptic seizures were found to be related to various types of intracranial lesions in NF1 patients. Methods The clinical characteristics of NF1 (1986–2006 in Chung-Gung Memorial Hospital), diagnosed on the basis of the criteria of the National Institutes of Health Consensus Conference (1988), were reviewed by 2 neurologists. We diagnosed epileptic seizures of NF1 patients on the basis of clinical appearances and a history of antiepileptic drugs. Magnetic resonance images were also evaluated by 2 neuroradiologists to confirm the locations of brain tumors or neurofibromatosis bright objects (NBOs). The locations of NBOs were classified into 4 categories: cortex and hippocampus, subcortical white matter, basal ganglia, and infratentorial area. The association between the location of the lesions and the occurrence of seizure in NF1 patients was analyzed statistically. Results The medical records of 630 NF1 patients were reviewed. In this cohort, 37 (5.87%) NF1 patients had epileptic seizures. The patients include 22 males (59.5%) and 15 females (40.5%). The mean seizure onset age was 14.8 years (2 months to 72 years). The most common seizure pattern was partial onset seizures, 3 simple partial seizures, and 14 complex partial seizures. Other seizure types found include 15 primary generalized seizures (2 absence seizures and 13 generalized tonic–clonic seizures), 2 infantile spasms, and 3 unclassified. A total of 172 (23 with epilepsy and 149 without epilepsy) NF1 patients underwent MRI examinations. NBOs were identified in 16 (69.6%) epilepsy patients and in 108 (72.5%) patients without epilepsy. The location or the number of these intracranial lesions does not show significant correlation with the occurrence of epilepsy in our cohort. Among 11 NF1 patients with intracranial tumors, 4 patients had seizures (36.36%), vs. 19 out of 161 NF1 patients (11.80%) without tumors. Conclusion The occurrence of epileptic seizures in NF1 patients is related to intracranial tumors but not to NBOs.

Effects of early systemic insults and the type of intracranial lesion on outcomes after traumatic brain injury

Effects of early systemic insults and the type of intracranial lesion on outcomes after traumatic brain injury

Severe Traumatic Brain Injury in Austria V: CT findings and surgical management

The aim of this paper is to describe CT findings and surgical management of patients with severe traumatic brain injury (TBI) in Austria. Data sets from 415 patients treated by 5 Austrian hospitals were available. The analysis focused on incidence, surgical management, and outcome of different types of intracranial lesions, and outcome of surgical interventions with and without monitoring of intracranial pressure (ICP). For the first analysis we assigned the patients to 16 groups based on the type of lesion as evaluated by CT scan. For the second analysis we created 4 groups based on surgical treatment (yes/no) and ICP monitoring (yes/no). The mean age was 48.9 years with a male to female ratio of 299:116. The most frequent single lesions were contusions (CONT) and diffuse brain edema. Combined lesions were far more common than single lesions; the most frequently observed combinations included CONT and subarachnoid hemorrhage (SAH) with or without subdural hematoma (SDH). Surgery was done in 276 (66.5%) patients. Osteoplastic surgery (OPS; n = 221) was the most common method followed by osteoclastic surgery (OCS; n = 91) and decompressive craniectomy (DEC; n = 15). ICU mortality was 29.7% for all patients who had any kind of surgery, which was lower than that of patients who were treated non-operatively (33.1%). The ICU mortality of patients with SDH was lower with OCS (18.8%) than with OPS (36.0%). Patients who received ICP monitoring but did not require surgery had the lowest 90 day mortality (17.5%). ICP monitoring seems to be beneficial in both operatively and non-operatively treated patients with severe TBI. Patients with SDH who were operated on had significantly better outcomes. In patients with SDH, their outcome after osteoclastic surgery was significantly better than after osteoplastic procedures.

Patients who Talk and Deteriorate: A New Look at an Old Problem

Background and Methods: We sought to review established prognostic indicators applied to Asian population, and to identify new risk factors for deterioration in patients who talked and deteriorated after traumatic brain injury (TBI). This retrospective study used our prospectively maintained TBI database. From August 1999 to July 2001, 324 patients were admitted to the neurosurgical intensive care unit (ICU). Thirty-eight patients (11.8%) talked between injury and subsequent deterioration into coma. Independent outcome predictors were studied. Results and Conclusion: Fourteen patients had subdural haematomas, 9 extradural haematomas, 19 contusions/haematomas and 3 subarachnoid haemorrhages. 81.5% of the patients had mass lesions potentially requiring surgery. Twenty patients had good functional recovery at 6 months (Glasgow Outcome Score 4 and 5); 18 were dead or vegetative. Age, gender, type of intracranial lesion and presence of coagulopathy were significantly correlated with outcome. Intracranial haematomas continue to be most significant in patients who talk and deteriorate. Coagulopathy was the strongest prognostic predictor of poor outcome with fibrinolytic parameters being reliable prognostic markers of head injury. Early identification, continued monitoring and treatment of coagulopathy should be our new look at improving outcome of these patients.

Primary canine and feline nervous system tumors: intraoperative diagnosis using the smear technique.

The recent application of neuroimaging techniques in veterinary neurology has led to the accurate localization of many types of intracranial lesions but has also created a clinical need, particularly with brain tumors, for a specific intraoperative diagnosis. For human brain tumors, a smear technique has been used successfully for many years to provide an extremely rapid, highly accurate intraoperative diagnosis. In similar smear preparations of intracranial lesions, obtained either by computed tomography (CT)-guided stereobiopsy or from a craniotomy, we have described distinguishing cytologic features of some primary spontaneous nervous system tumors in 80 dogs and 13 cats. A final diagnosis was confirmed by evaluation of paraffin-embedded sections from the same sample and, when appropriate, by immunocytochemical staining. Preliminary findings indicate that, in dogs and cats, this procedure is useful for rapid, accurate intraoperative diagnosis of many primary nervous system tumors. The distinguishing features of the canine and feline tumors bear a remarkably close resemblance to their human counterparts.

Coexisting diffuse axonal injury (DAI) and outcome of severe head injury.

The importance of coexisting diffuse axonal injury (DAI) and outcome were studied in 107 patients with diffuse and focal brain injury. Comprehensive neuropathological study was undertaken in 26 fatal patients. There was a clear rank order of the mortality rate in the lesion type. The rank order of good recovery and moderate disability was also similar to the inverse of the mortality ranking. The pathological "marker" of DAI, macroscopic lesions in the corpus callosum and dorsolateral quadrant of the upper brainstem and histological evidence of axonal retraction balls, were commonly found not only in patients with diffuse brain injury but also in focal brain injury. The type of intracranial lesion in severe head injury is thus an important factor in determining outcomes and DAI of varying severity is the common subjacent lesion in the fatal patients.