Expression of Sigma-Class Glutathione-S-Transferase in Fetal and Pediatric Filum Terminale Samples: A Comparative Study.

Background and objectives: The pathophysiology of tethered cord syndrome (TCS) in children is not well elucidated. An inelastic filum terminale (FT) is the main factor underlying the stretching of the spinal cord in TCS. Our study aimed to investigate the expression of glutathione-S-transferase (GST) in children and fetal FT samples in order to understand the relationship between this enzyme expression and the development of TCS. Materials and Methods: FT samples were obtained from ten children with TCS (Group 1) and histological and immunohistochemical examinations were performed. For comparison, FT samples from fifteen normal human fetuses (Group 2) were also analyzed using the same techniques. Statistical comparison was made using a Chi-square test. Results: Positive GST-sigma expression was detected in eight (80%) of 10 samples in Group 1. The positive GST-sigma expression was less frequent in nine (60%) of 15 samples from Group 2. No statistically significant difference was detected between the two groups (p = 0.197). Conclusions: Decreased FT elasticity in TCS may be associated with increased GST expression in FT. More prospective studies are needed to clarify the mechanism of the GST-TCS relationship in children.

The evaluation of the effects of steroid treatment on the tumor and peritumoral edema by DWI and MR spectroscopy in brain tumors.

OBJECTIVE: To investigate the effects of dexamethasone on brain tumor and peritumoral edema by different sequences of magnetic resonance imaging (MRI). MATERIALS AND METHODS: MRI was performed in 28 patients with brain tumor. Patients were divided into the 3 groups based on the histological diagnosis; Group I: high-grade glial tumor, Group II: low-grade glial tumor, and Group III: brain metastasis. The measurements of peritumoral edema volume and apparent diffusion coefficient (ADC) values were performed while the peak areas of cerebral metabolites were measured by spectroscopy in groups I and II. The changes in edema volumes, ADC values and cholin/creatine peak areas were compared. RESULTS: The volume of peritumoral edema was decreased in groups I and II, but increased in group III after dexamethasone treatment. These changes were not statistically significant for 3 groups. ADC value was decreased in group I and increased in groups II and III. Changes in ADC values were statistically significant. Cholin/creatine peak areas were decreased after dexamethasone in groups I and II, but these changes were also not significant. CONCLUSION: Dexamethasone has no significant effect on the volume of peritumoral edema in glial tumor and metastasis. Moreover, dexamethasone increases the fluid movements in low grade gliomas and metastases, decreases in high grade gliomas. However, more comprehensive clinical studies are needed to show the effects of dexamethasone on brain tumors and peritumoral edema.

Histological structure of the medial and lateral walls of cavernous sinus in human fetuses.

PURPOSE: The aim of this study is to elucidate the architecture of these fine structures in human fetuses. METHODS: The histological examination of medial wall (MW) and lateral wall (LW) was performed in 15 normal human fetuses. Eleven fetuses were female and four were male. The gestational age ranged between 14 and 35 weeks. The weight ranged between 180 and 1750 g. The wall samples (two MW and two LW from each fetus) were obtained by microsurgical technique and underwent histological examination. Each wall was examined for the structure and composition of collagen and elastic fibers, ganglions, peripheral nerves, and vessels. RESULTS: A total of 60 wall samples (30 MW and 30 LW) were examined in 15 fetuses. Loose connective tissue composed of type III collagen was observed in both of the walls. Elastic fibers were observed only in three wall samples (two MW and one LW). Ganglion was detected in 11 samples (nine in LW and two in MW), and peripheral nerve was found in 28 walls (18 LW and 10 MW). Vessels were observed in 51 samples (26 LW and 25 MW). None of the walls was stained with type I collagen. CONCLUSIONS: The structure of LW and MW of the cavernous sinus (CS) in fetuses is mainly composed of collagen tissue while some elastic fibers are supported by this tissue. Type III collagen is the main component of fetal CS walls. Because of the weak histological structure, CS may be more prone to tumor invasion in infants.

Morphological structure and variations of lumbar plexus in human fetuses.

The objective of this study is to study the anatomy of lumbar plexus on human fetuses and to establish its morphometric characteristics and differences compared with adults. Twenty lumbar plexus of 10 human fetal cadavers in different gestational ages and genders were dissected. Lumbar spinal nerves, ganglions, and peripheral nerves were exposed. Normal anatomical structure and variations of lumbar plexus were investigated and morphometric analyses were performed. The diameters of lumbar spinal nerves increased from L1 to L4. The thickest nerve forming the plexus was femoral nerve, the thinnest was ilioinguinal nerve, the longest nerve through posterior abdominal wall was iliohypogastric nerve, and the shortest nerve was femoral nerve. Each plexus had a single furcal nerve and this arose from L4 nerve in all fetuses. No prefix or postfix plexus variation was observed. In two plexuses, L1 nerve was in the form of a single branch. Also, in two plexuses, genitofemoral nerve arose only from L2 nerve. Accessory obturator nerve was observed in four plexuses. According to these findings, the morphological pattern of the lumbar plexus in the fetus was found to be very similar to the lumbar plexus in adults.

Revision Cranioplasty with Three-dimensional Custom-made Titanium Implants in Patients with Failed Cranioplasty.

OBJECTIVE: Graft failure is a common complication of cranioplasty. Revision cranioplasty is required to overcome this complication. However, no previous studies have reported outcomes in revision cranioplasty with 3-dimensional (3D) custom-made titanium implants. We describe our experience with 3D titanium implants in patients with revision cranioplasty. METHODS: We evaluated 43 consecutive patients between January 2011 and December 2019 who underwent revision cranioplasty using 3D custom-made titanium implants. The 3D image of the patient's cranium and the plan to close the cranium defect were created in a virtual environment using software programs. Demographic and radiologic features were compared based on the materials used in the initial cranioplasty. RESULTS: Previous material was autologous graft (AG) in 27 patients and polymethyl methacrylate (PMMA) in 16 patients. The mean time without revision cranioplasty is longer in patients with PMMA implants than in patients with AG. There was no statistically significant difference in the length of hospital stay between patients with PMMA implants and patients with AG. There were no postoperative adverse events such as infection, wound dehiscence, convulsions, or epidural hematoma in 38 patients during hospitalization. Wound dehiscence developed in 5 patients and surgical repair was required in one. CONCLUSIONS: Initial cranioplasty with PMMA provides a longer time period than the AG before the revision. However, both of them have similar outcomes based on length of hospital stay and cranial defect area. Custom-made 3D titanium implant is a good option for revision cranioplasty to prevent implant failure and reduce patients' cosmetic concerns.

Comparison of Surgical Techniques for Intracranial Arachnoid Cysts: A Volumetric Analysis.

AIM: To compare the volumetric changes of intracranial arachnoid cysts (IACs) in different surgical techniques. MATERIAL AND METHODS: Sixty-six patients who underwent IAC surgery in our department between 2010 and 2020 were studied retrospectively. Based on the surgical technique, clinical and volumetric changes, postoperative complications, recurrence rates, and length of hospital stay were statistically compared. RESULTS: Microsurgical fenestration (MF) was performed on 32 (48.5%) patients, endoscopic fenestration (EF) on 17 patients, cystoperitoneal shunt (CPS) on 11 patients, and EF + CPS in six patients. The mean IAC volume change rate was 68.54 mL, and the mean cyst volume change rate was 40.68%. The MF technique produces a significantly greater mean cyst volume change than the EF technique. The mean volume change in sylvian IAC is 4.8 times greater than in posterior fossa IAC, a significant difference. The mean cyst volume change is four times greater in patients with skull deformity than in patients with balance loss, and this difference is statistically significant. In patients with cranial deformity, the mean cyst volume change is 2.6 times greater than in patients with neurological dysfunction. This difference is also statistically significant. The volume of IAC decreased more in patients with postoperative complications, with a significant difference between the postoperative complication and the change in IAC volume. CONCLUSION: MF can achieve better volumetric reduction in IAC, particularly in patients with sylvian arachnoid cysts. However, more volumetric reduction increases the risk of postoperative complications.

Risk Factors and Surgical Treatment Options for Intracranial Infections.

AIM: To present our experience on intracranial infections, and to determine the possible locations as well as the risk factors for surgical treatment. MATERIAL AND METHODS: Over 13 years, 103 patients with intracranial infection underwent surgical evacuation. Seventy-one (68.9%) patients were men, and the mean age was 38.57 years. For intracranial infections, direct and indirect microbiological identification methods were used. The clinical and radiological data of patients were retrospectively analyzed and compared statistically based on the type of infection, location, history of previous surgery, comorbid diseases, and demographic features of the patients. RESULTS: Forty-six (44.7%) patients had intraparenchymal abscess, 25 (24.3%) had subdural empyema, and 32 (31.0%) had epidural empyema. Emergent surgical evacuation was performed in 60 (58.25%) patients. Microbiological agents were not isolated in 26 (25%) patients, while multiple microorganisms were isolated in 17 (16.5%) patients. Intraparenchymal abscesses are more common in the frontal lobe and cerebellum, while subdural empyemas are located more frequently in the frontoparietal region. There was no significant difference between intracranial infection and age, gender, history of surgery, and preoperative antibiotic use. However, a statistically significant relationship between intracranial infection, history of previous surgery, and the patient?s comorbid disease was found. Specifically, intraparenchymal abscesses were more frequently detected in immunocompromised patients, and subdural empyemas were common in patients with previous tumor surgery. CONCLUSION: Brain abscesses commonly develop in the frontal lobe and cerebellum. Patients who underwent previous cranial surgery and patients with comorbid diseases are more prone to intracranial infections. Large abscesses with significant edema are best candidates for emergent surgical evacuation.

Simultaneous Closure of Bilateral Cranial Defects Using Custom-Made 3D Titanium Implants: A Single Institution Series.

AIM: To investigate the outcomes of the simultaneous closure of bilateral cranial defects using custom-made three-dimensional (3D) titanium implants. MATERIAL AND METHODS: Demographic data of 26 patients with bilateral cranial defects who underwent cranioplasty using the 3D custom-made titanium implants in our clinic between 2017 and 2022 were retrospectively reviewed. Data on the area of cranium defect, the time interval between last cranial surgery and cranioplasty, postoperative complications, etiology of the cranium defect, and hospitalization of the patient were statistically evaluated. RESULTS: The incidence of bilateral cranioplasty was 19.11%. The gender distribution of patients was 4 (15.4%) female and 22 (84.6%) male, with a mean age of 29.08 ± 14.65 years. The mean defect area was 35.0 ± 19.03 and 29.24 ± 22.51 cm2 on the right and left sides, respectively. The etiology of the cranium defect was gunshot wounds in 12 patients, and 14 patients had a history of trauma-related injuries such as falls and vehicle accidents. Eight patients had a history of failed cranioplasty with autologous bone. Postoperative complications were wound dehiscence in two patients and diffuse cerebral edema in one patient. No mortality was recorded. CONCLUSION: The custom-made cranioplasty is feasible for simultaneous closure of bilateral cranial defects. Many complications can be prevented by careful preoperative evaluation before surgery and an appropriate implant selection for the patient.

Unilateral hyperplasia of lamina and spinous process of C6 vertebra: case report.

We report a 20-year-old male patient who was admitted to our emergency clinic after a traffic accident and who suffered from neck pain. Radiographic examination of the cervical spine showed hypertrophy of the left lamina and hypertrophy and elongation of the left spinous process of the sixth cervical vertebra (C6). A computed tomography scan revealed the associated schisis of the spinous process at the same level. Magnetic resonance imaging scan demonstrated no abnormality of the neural elements. The patient underwent a surgical operation due to persistent neck pain and the local aesthetic abnormality.

Comparison of intrathecal dotarizine and nimodipine treatments in cerebral vasospasm after subarachnoid hemorrhage: an experimental study in rabbits.

BACKGROUND: cerebral vasospasm (CVS) is one of the most considerable complications of subarachnoid hemorrhage (SAH). The aim of this study was to assess and to compare the ability of intrathecal dotarizine and nimodipine to prevent and treat vasospasm in a rabbit model of subarachnoid hemorrhage. METHOD: thirty male New Zealand white rabbits weighing 2,500-3,000 g were allocated into five groups randomly. The treatment groups were as follows: Control, only SAH, SAH/Dotarizine, SAH/Nimodipine, SAH/Vehicle. Forty-eight hours after SAH injection, all animals underwent femoral artery catheterization procedure by open surgery under anesthesia and angiography performed for each animal in the fifth day just before sacrifice. FINDINGS: basilar artery vessel diameters are measured by angiography. Basilar artery vessel diameters and luminal sectional areas are measured in pathology slides. There was a statistically significant difference between the mean basilar artery cross-sectional areas and the mean arterial wall thickness measurements of the control and SAH-only groups (p < 0.05). CONCLUSIONS: these findings demonstrate that calcium channel blocker dotarizine has marked vasodilatory effect in an experimental model of SAH in rabbits. Nimodipine is an effect-proven agent in CVS, but dotarizine may take place of it.