Intimal Hemorrhage of Basilar Artery Induced by Severe Vasospasm Following Subarachnoid Hemorrhage: The Experimental Analysis.

BACKGROUND: Cerebral vasospasm, a serious complication of subarachnoid hemorrhage (SAH), has been extensively studied for its neurochemical and pathophysiologic mechanisms. However, the contribution of inner elastic membrane dissection and subintimal hemorrhage to basilar artery occlusion remains underexplored. This study investigates inner elastic membrane-related changes in the basilar artery after SAH. METHODS: Twenty-four hybrid rabbits were divided into control, sham, and SAH groups, with SAH induced by autologous blood injection. After 2 weeks, basilar artery changes, vasospasm indexes (VSIs), and dissections were evaluated. RESULTS: The SAH group showed significantly higher VSI, with vascular wall thickening, luminal narrowing, convoluted smooth muscle cells, intimal elastic membrane disruption, endothelial cell desquamation, and apoptosis. Some SAH animals exhibited subintimal hemorrhage, inner elastic membrane dissection, and ruptures. Basilar arteries with subintimal hemorrhage had notably higher VSI. CONCLUSIONS: These findings highlight the role of subintimal hemorrhage and inner elastic membrane dissection in basilar artery occlusion post-SAH, offering valuable insights into vasospasm pathophysiology.

Localization of Intracranial Lesions Using Superficial Stereotaxic Cranial Lesion Locator Based on Magnetic Resonance Images.

BACKGROUND: Detection of a deep-seated lesion located in the brain parenchyma and major neuroanatomical sites is a critical issue in neurosurgery. Some neurosurgical cranial navigation systems have been developed that are available; however, some preparation is necessary, including the installation of complex computer software programs and obtaining specific neuroradiological images. OBJECTIVE: The purpose of this experimental study was to design and evaluate a superficial stereotaxic frameless lesion locator in order to localize mass lesions within the brain. METHODS: A superficial stereotaxic frameless lesion locator system was designed using cardboard and the Cartesian coordinate system as a reference framework. This material was used in a model creating printed magnetic resonance images in the superficially marking of the lesion. This material easily located the lesion placement and superficially projected the lesion location. RESULTS: The results of this study revealed that the superficial stereotaxic frameless lesion location procedure using a coordinate cardboard locator is a safe, fast, and simple procedure. This procedure provides an accurate means of locating the target lesion seated within the brain parenchyma. When compared with other models, we found that this device is reliable and has a high rate of superficial lesion detection. CONCLUSION: A superficial lesion locator may be used in clinical practice. This experimental study demonstrated the usability and reliability of the procedure. Additional detailed investigations are necessary to improve the procedure.

Reconsideration of Neurogenic Pulmonary Edema as Source of Metastatic Cerebral Abscess Following Subarachnoid Hemorrhages: A Preliminary Study.

BACKGROUND: Subarachnoid hemorrhage (SAH) may be a cause of neurogenic pulmonary edema (NPE). It is well known that lymphatic fluid draining by thoracic duct to lungs consists of many dangerous metabolites, degraded tissue particles, and microbiologic pathogens. However, not enough studies have investigated whether NPE causes septicemia or not. In this study, we retrospectively examined our experimental materials to determine whether there is a meaningful relationship between NPE and cerebral abscess formation. METHODS: Forty-two rabbits were divided into 3 groups: Control (n = 5), SHAM (n = 7), and SAH (n = 30) with severe neurogenic lung edema detected in rabbits. The SHAM and SAH groups received 1 mL saline and 1 mL autologous arterial blood into the Sylvian cisterna, respectively. Weight, heartbeat, respiration rate, and blood pressure were recorded by routinely using monitoring devices. All multilevel lungs and brain tissue microsections were examined by stereologic and Cavalier methods. For statistical analysis, NPE criteria and the numbers of abscess or abscess resembling cores in the brains were estimated in all groups and compared. The Mann Whitney-U test was used to analyze the results statistically. RESULTS: All rabbits were around 4 years old; body weight was between 3.94 and 4.5 kg; normal heart rhythm rate was found between 251 ± 39/minutes and 281 ± 30/minutes; and respiration rate was between 24 ± 5/minutes and 36 ± 7/minutes. Histopathologic examinations showed that abscess formations frequently spread in middle cerebral arterial territories of all animals in the NPE-detected rabbits. While average abscess numbers were estimated as 3 ± 1 in 7 animals (n = 7; P < 0.005) in severe NPE-detected rabbits, only 1 ± 1 abscess core was detected in a less severe NPE that developed in 3 (n = 3; P < 0.05) animals. The vasospasm index values of pulmonary arteries (PAs) of all animals were 1.233 ± 0.065 in the control group; 1.567 ± 0.0430 in the SHAM group, and 2.890 ± 0.0453 in the SAH group (P < 0.05). CONCLUSIONS: This experimental study showed that NPE is a relatively common pathology following experimental SAH in rabbits. The NPE is frequently complicated with brain abscess as shown in this study. The pathophysiologic mechanism was concluded, as NPE may be responsible for cerebral abscess development via bacteria/cytotoxic particles conveyed by thoracic duct to lungs and transferred from the ruptured alveoli-capillary membrane to the brain by way of systemic circulation.

Using of Fresh Cadaveric Cow Brain in the Microsurgical Training Model for Sulcal-Cisternal and Fissural Dissection.

OBJECTIVE: The aim of this experimental study was to evaluate the feasibility of using fresh cadaveric cow brain as in a training model for microsurgical dissection of sulcus, cisterns, and fissure. METHODS: Experimental microneurosurgical activities in this study were performed under the operating microscope. Bilateral sylvian cisterns, interhemispheric fissure, and hemispheric sulcus of the fresh cadaveric cow brain were used as an interested area for this experimental study. The dissection was continued reaching down to the floor of the cistern and total dissection of the middle cerebral artery inside the cisternal space. The suitability of a cow brain as a training model for sylvian fissure microdissection was evaluated as three groups; bad, good, and perfect. RESULTS: Ten uncovered fresh cadaveric cow brains were used in this experimental feasibility study. The suitability of the experiment for training model was evaluated as bad in (1) 10% of the fresh cadaveric cow brains. The suitability was found as good in (6) 60% of the procedures. In the remaining (3) 30% of the brain dissection, the suitability of the experiment was evaluated as perfect. CONCLUSION: In conclusion, performing the sulcal, cisternal, and fissural dissection and protecting the neural and vascular tissue from the mechanical bruising effect of metallic microsurgical instruments are feasible as shown in this study. We believe that this training model will contribute to the practical micro-neurosurgery. Additionally, it provides adequate performance for the microsurgical intervention.

[Pediatric head injuries, retrospective analysis of 851 patients: an epidemiological study]. / Çocukluk çagi kafa travmalari, 851 olgunun retrospektif degerlendirilmesi: Epidemiyolojik bir çalisma.

BACKGROUND: The aim of this study was to contribute to the epidemiological database of our country about pediatric head injuries. METHODS: We retrospectively analyzed 851 patients younger than 14 years old with head injury, treated in the Neurosurgery Department of Samsun Mehmet Aydin Education and Research Hospital between January 2003 and June 2008. RESULTS: Five hundred and fifty (65%) patients were male and 301 (35%) were female. Falls (70%) were the most common cause of head injury. According to Glasgow Coma Score (GCS), 74% of patients had mild (13-15), 22% moderate (9-12) and 4% severe (3-8) head injury. Eighty-seven (10.5%) patients were operated. The commonest operations were performed for depressed fractures and epidural hematomas. The mortality rate was 3.8% (33). Common causes of mortality were traffic accidents and falls from heights. CONCLUSION: Other reported studies and this study show that the majority of pediatric head injuries occur as a result of preventable causes. It is important to have local epidemiological studies and data about head injuries in order to prevent these traumas before their occurrence.

[Retrospective analysis of 954 adult patients with head injury: an epidemiological study]. / Kafa travmasi nedeniyle tedavi edilen 954 eriskin olgunun retrospektif degerlendirilmesi: Epidemiyolojik çalisma.

BACKGROUND: Head traumas are among the most common causes of mortality and morbidity among young adults in urban areas. We aimed to contribute to the epidemiological database of our country with regard to head traumas. METHODS: We retrospectively analyzed 954 patients older than 15 years with head trauma who were treated in the Neurosurgery Department of Samsun Mehmet Aydin Education and Research Hospital between January 2003 and June 2008. Seven hundred twenty-one (75.5%) patients were male and 233 (24.5%) were female. Five hundred twenty-one (52.5%) were between 15-40 years old. RESULTS: Traffic accident (75%) was the most common cause of head trauma. According to Glasgow Coma Score (GCS), 48% of the patients had mild (13-15), 31% moderate (9-12) and 21% severe (3-8) head injury. One hundred seventy-seven (18.5%) patients were operated. The commonest operations were performed for subdural and epidural hematomas. Mortality was 19.4% (185). Common causes of mortality were traffic accidents (77%) and gunshot injuries. CONCLUSION: It is important to have local epidemiological studies and data about head traumas in order to prevent these traumas. In this study, the predominance of young men and the causes of trauma and mortality were similar to that reported in the related literature.

Neuroprotective effects of methylprednisolone and hypothermia after experimental spinal cord injury: a histopathological and stereological study.

OBJECTIVE: Spinal cord injury is a common trauma among severe accidents in which the spinal cord has been severed; intravenous methylprednisolone and hypothermia are widely used in the treatment of traumatic spinal cord injuries. However, no common consensus has been reached on therapeutic approaches to prevent and reduce disability caused by spinal cord injuries. In this study, the efficacy of methylprednisolone and hypothermia treatments after experimental spinal cord injury made by dynamic weight-drop model in rabbits was investigated. MATERIALS AND METHODS: This experiment consists of three groups: injured, methylprednisolone-treated and hypothermia-treated groups. The methylprednisolone-treated group received intravenous methylprednisolone (30 mg/kg/day) immediately after spinal cord injury for three days. In the hypothermia-treated group, cold isotonic saline (5°C) was infused via a cannula into the epidural space at a rate of 10 ml/min. The temperature of the tissue was allowed to reach 25ºC, and then isotonic saline solution was given at a rate of 5 ml/min for 3 hours. Saline was given to the injured group following spinal cord injury. After 1 week of experimental injury, mid-thoracic level tissue was removed from the spinal cord for histopathological evaluation and subsequent stereological analysis. RESULTS: The volume of spinal cord segment, not only parenchyma of grey and white matter but also cavity, was estimated by the Cavalieri principle. Significant differences were seen between the injured group and methylprednisolone /hypothermia-treated groups in terms of the total volume cavity of spinal cord segment; cavity volume in the grey matter and cavity volume in the white matter. No significant differences were seen between methylprednisolone and hypothermia-treated groups in terms of the total volume cavity of spinal cord segment; cavity volume in the grey matter and cavity volume in the white matter. CONCLUSIONS: These results suggested that both methylprednisolone and hypothermia treatment are neuroprotective in preventing spinal cord tissue from tissue damage after experimental injury.

A simple technique for localizing consecutive fields for disector pairs in light microscopy: application to neuron counting in rabbit spinal cord following spinal cord injury.

Locating the same microscopic fields in consecutive sections is important in stereological analysis. The tools for achieving this requirement have limited number in practice. This paper presents a simple and inexpensive technique for localizing the same fields on disector pairs in conventional light microscopes equipped with widely available dial indicators. It is partly a modification of equipment previously described. The presented procedure requires two light microscopes equipped with dial indicators and modified slide clips. An application of the present system was shown in a model of spinal cord injury (SCI). A midthoracic laminectomy was performed leaving the dura intact. A contusion was done at the level of midthoracic spinal cord segments (T7-T8) by dropping a 10-g mass from a height of 30 cm. The subjects were randomly divided into three groups (10 animals in each): hypothermia group, methylprednisolone group, and traumatic spinal cord injury alone group. Present results show that treatment with hypothermia after spinal cord trauma has a neuroprotective effect on cell damage but not in the methylprednisolone treatment group.