Pineal Tumor Surgery-The Choice of the Approach Related to Tumor Characteristics and Posterior Fossa Anatomy.

OBJECTIVE: This research aimed to determine whether an adequate surgical approach can be chosen based on clearly defined values of anatomical landmarks (tentorial angle) and tumor size and extension. METHODS: We conducted a retrospective analysis of patients operated on because of pineal tumors. The cohort was divided depending on the surgical approach. On preoperative magnetic resonance imaging, we measured maximal diameters, tumor volume, and tumor propagation. In the group of patients operated with the supracerebellar infratentorial approach, we also tested the correlation of tentorial angle with residual tumor. Differences among groups in resection, complications rate, and outcome were tested by the χ2 test. Finally, in both groups, the correlation of residual tumor with tumor volume, propagation, and diameters was tested using the receiver operating characteristic curve. RESULTS: In the group operated with a supracerebellar approach, total resection was achieved in 78% of the patients. The critical value of cranio-caudal diameter correlated with tumor residue was 31 mm, for lateral-lateral diameter 25 mm, for the lateral extension 14 mm, and tumor volume 12 cm3. Tentorial angle did not influence the extent of the resection. In the group operated with an occipital transtentorial approach, the critical tumor volume related to tumor residue was 9 mm3, anterior-posterior diameter 29 mm, and cranio-caudal diameter 28 mm. The extent of the resection was significantly higher in the supracerebellar group. CONCLUSIONS: In both approaches, tumors larger than 3 cm show an increased risk of subtotal resection. Except when most tumor volume is localized above the venous system, we advocate a supracerebellar corridor as an effective approach that is not limited by tentorial angle.

Reconstruction of Moderately and Severely Atrophic Scalp-A Multicentric Experience in Surgical Treatment of Patients Irradiated for Tinea Capitis in Childhood and Surgical Algorithm.

Background and Objectives: Before the introduction of griseofluvin, the use of X-ray radiation was the treatment of choice for tinea capitis. More than half a century later various types of tumors have been found to be associated with childhood irradiation due to tinea capitis, most commonly cancers of the head and neck, as well as brain tumors. The often unusually aggressive and recurrent nature of these tumors necessitates the need for repeated surgeries, while the atrophic skin with an impaired vascular supply due to radiation often poses an additional challenge for defect reconstruction. We present our experience in the surgical treatment of such patients. Materials and Methods: This is a retrospective cohort study. In this study, 37 patients treated for acquired defects of the scalp with a history of irradiation therapy due to tinea capitis in childhood were included in this study, 24 male and 13 female patients. The mean age at the first appointment was 60.6 ± 7.8, with the youngest included patient being 46 and the oldest being 75 years old. Patients' characteristics, surgical treatment, and complications were analyzed and a reconstructive algorithm was developed. Results: Local flaps were used for reconstruction in 34 patients, direct sutures were used in 10 patients and 20 patients received split-thickness skin grafts for coverage of both primary and secondary defects for reconstruction of flap donor sites. One regional flap and one dermal substitute covered by an autologous skin graft were also used for reconstruction. Complications occurred in 43.2% of patients and were significantly associated with the presence of comorbidities (p = 0.001), aseptic bone necrosis (p = 0.001), as well as skin atrophy in frontal, occipital, and parietal region (p = 0.001, p = 0.042 and p = 0.001, respectively). A significant correlation between major complications and moderate skin atrophy was found only in the parietal region (p = 0.026). Conclusions: Unfortunately, many protocols developed for scalp reconstruction are not applicable in the setting of severe or diffuse scalp skin atrophy associated with high tumor recurrence rate and radiation-induced vascular impairment, such as in tinea capitis patients in Serbia. An algorithm has been developed based on the authors' experience in managing these patients.

Effects of subchronic methionine stimulation on oxidative status and morphological changes in the rat ileum.

This study was conducted to explore the effects of sulfur containing amino acids on redox status and morphological parameters in the rat ileum tissue. Male Wistar albino rats were randomly divided into the following groups: Group K (saline (1 ml/day, i.p.)), Group M (methionine (0.8 mmol/kg/day, i.p.)), Group C (methionine (0.8 mmol/kg/day) + L-cysteine (7 mg/kg/day), i.p.) and Group N (methionine (0.8 mmol/kg/day) + N-acetyl-L-cysteine (50 mg/kg/day), i.p.). Activities of antioxidant enzymes in the ileum were analyzed to profile oxidative status. Morphometric analysis included measurement of villus height (µm), tunica mucosa thickness (µm), tunica muscularis thickness (µm), the total thickness of the ileal wall (µm) and the number of cells in the lamina propria (per 0.1 mm2 of tissue). Results showed that methionine treatment reduced the activity of antioxidant enzymes (SOD, GPx, CAT) and the GSH content compared to the control group (p > 0.05). The application of methionine reduced the following parameters statistically significant compared to the control group: length of the ileal villi (p < 0.01), tunica mucosa thickness (p < 0.01), and ileal wall thickness (p < 0.01). We concluded that methionine induced the changes in the gut redox status, which implied oxidative stress occurrence. L-cysteine and N-acetyl-L-cysteine both exhibited antioxidant properties.

Suppression of methionine-induced colon injury of young rats by cysteine and N-acetyl-L-cysteine.

Changes in the methionine metabolism can cause a state called hyperhomocysteinemia, inducing oxidative stress in the gut. The production of free radicals is important in the colon damage caused by methionine. This study aimed at evaluating the effect of the use of L-cysteine and N-acetyl-L-cysteine on the colon morphometry of young rats treated with methionine. A total number of 32 male rats were distributed in a randomized experimental design in 4 groups: control group treated with saline; methionine group; cysteine + methionine group, and N-acetyl-L-cysteine + methionine group. After 21 days of treatment, rats were sacrificed and the colon samples were taken for histological and biochemical analysis. Methionine load increased depth of crypts, the lamina muscularis mucosae thickness, the mucosal height, and the number of cells in lamina propria (p < 0.01). Combination of methionine with L-cysteine (C group) and with N-acetyl-L-cysteine (N group) reversed methionine effects. Methionine treatment increased the GPx activity and MDA concentration, while L-cysteine and N-acetyl-L-cysteine increased the catalase activity compared to methionine group. It was concluded that the use of L-cysteine and N-acetyl-L-cysteine was beneficial to decrease intestinal mucosal height and oxidative damage when methionine was used in combination with them.

Determination of Predictive Anatomic Parameters for Bleeding of Brain Arteriovenous Malformations by Multidetector CT Angiography.

Patients with brain arteriovenous malformation (AVM) have a certain risk to bleed, and the goal of this study was to examine the effect of radiological and clinical predictive characteristics of AVM hemorrhage using multidetector computed tomographic (MDCT) angiography. The study included a series of 57 patients, mean age 35.46 years, who were diagnosed during their hospitalization at Clinical Department of Neurosurgery, Clinical Center of Serbia, in the period from January 2008 to March 2016. In all patients, the diagnosis was made using MDCT angiography. Two groups of patients were observed. The first group included patients who did not initially present with hemorrhage, while the second group initially presented with hemorrhage. Both groups were treated with medical therapy or a combination of medical therapy with embolization/surgery/radiotherapy. Deep venous drainage (p<0.05), combined arterial supply from different basins (p<0.05) with a length <60 mm, venous dilatation present in the drainage vein (p<0.01), and the angle of casting sup-ply arteries in the nidus (p<0.01) carry a risk of repeated bleeding. In the group of patients who had initial hemorrhage, the mean value of the casting angle size was 130°, while in the group that did not have initial bleeding the mean value of the measured angle size was 103.81° with standard deviation of 17.21° (p<0.01). In conclusion, AVMs with deep venous drainage from the carotid and vertebrobasilar basin, the length of the feeding arteries <60 mm, the angle of the casting feeding arteries in the nidus ≥130° and dilatation and/or venous aneurysm of drainage vessel are predictive for clinical presenting by hemorrhage.

Adult Brainstem Gliomas: Retrospective Analysis of 51 Patients.

AIM: Brainstem gliomas (BSG) constitute less than 2% of brain tumors in adults. Therapeutic options are limited and BSG are associated with a high morbidity and mortality. MATERIAL AND METHODS: We reviewed the records of 51 patients with BSG treated at the Institute of Neurosurgery, Clinical Center of Serbia in Belgrade between 1998 and 2012. We recorded demographic and clinical variables as well as radiological findings and survival. RESULTS: Of the 51 patients, 62.7% were male and 37.3% were female. The mean age was 30.6±19.3 years. High grade glioma (Astrocytoma grade III and IV) was most common at the age of 38.2±17.9 years (t=.481, p=0.017) while low grade glioma (Astrocytoma grade I and II) was common in younger age as 25.4±17.4 years (X2=4.013; p=0.045), with localization in the pons (X2=5.299; p=0.021) and exophytic presentation (X2=3.862; p=0.049). Ataxia, as initial symptom, was a predictor of poor outcome (HR:5.546, p=0.012). CONCLUSION: Due to its specific localization, BSG present a major challenge for neurosurgery, because of the necessity of safe approach for radical resection. Histological verification of BSG determines the need for additional therapeutic procedures such as radiotherapy and chemotherapy. Benefit from correct diagnosis is reflected in the avoidance of potentially adverse effects of treatment.

GLIOBLASTOMA MULTIFORME BRAIN TUMORS LOCATED IN THE MOTOR CORTEX--SPECIFIC FINDINGS IN COMPARISON WITH LOW GRADE GLIOMAS OF THE SAME LOCALIZATION: ANALYSIS OF A SIXTY PATIENT SERIES.

The verified presence of a glioblastoma multiforme (GBM) tumor in the motor area of the brain, in a patient lacking preoperative neurological deficit, offers no certainty that the tumor can be radically removed without the possibility of causing postoperative motor deficit. We present a series of 60 patients hospitalized at the Clinical Department of Neurosurgery, Clinical Center of Serbia in Belgrade between October 2011 and February 2015, harboring tumors located within and in the vicinity of the motor zone of the brain. By using Karnofsky's index (KI), the pre- and postoperative conditions of the patients were evaluated. Regarding electrical stimulation of the motor cortex, significantly lower values of the electrical current intensity, frequency, and pulse wave duration (p < 0.01) were needed for triggering motor response in case of GBM tumor compared to a slowly growing tumor (low-grade). Patients with low-grade gliomas (LGG) had statistically significantly higher KI values pre- and postoperatively than patients with GBM (p < 0.01). Using electrical stimulation of the cortex, a higher grade of resection of LGG could be achieved as compared with the group presenting with GBM (χ² = 5.281; df = 1; p < 0.05). Our findings and review of the results reported by other authors underline the necessity of routine application of electrical stimulation of the cerebral cortex in order to identify the primary motor field (M1).

The results of treatment of primary brain tumors in children.

During the period of 2009-2011 in UCH in Belgrade, we treated 22 patients with brain tumors. Treatment included the diagnosis and therapy that included surgery and postoperative neuroradiological follow-up of all patients regardless of whether radiotherapy was conducted with or without chemotherapy. The most frequent were low grade astrocytomas and medulloblastomas. Patients with supratentorial localization of tumor had significantly smaller neurological sequelae compared with patients with infratentorial as well as patients diagnosed with low grade astrocytomas of any localization. From 10 patients with supratentorial localization, 7 of them had no neurological deficit, while from 11 patients with infratentorial localization, 3 of them were Without deficit. Patients with histological diagnosis of low grade astrocytoma of any localization had less neurological deficits compared with other tumors. From 7 low grade astrocytoma in 5 of them there was no neurological deficit, while only in one patient residual tumor was verified. In 7 patients the rest of the tumor was diagnosed, while in 14 patients no residual tumors was diagnosed during follow-up based on the MRI diagnosis. Surgery, postoperative radiotherapy and chemotherapy in some cases represent an effective therapeutic approach in the treatment of brain tumors in children.