Vaso Antunovic’s research while affiliated with Klinički centar Srbije and other places

Intraventricular hemorrhage occurs in almost one fifth of prematurely born children. Due to present complications, such as hydrocephalus and neurological deficit, it endangers the child's life, therefore there is the need for understanding and prevent risk factors as well as the need for finding most optimal methods of treatment. The aim of the study was to point out the current therapeutic modalities of the treatment of posthemorrhagic hydrocephalus in prematurely born children. The study included 60 patients divided into two groups of 30 patients treated at the University Children's Hospital of Belgrade in the period 2003-2008. Treatment outcome of the control group of patients treated by standard methods was influenced by gestational age (p=0.024), head circumference on birth (p = 0.043), body mass on birth (p = 0.006), Apgar score on birth (p < 0.001), peripartum asphyxia (p < 0.001), cardiorespiratory arrest (p < 0.001), respiratory distress (p = 0.002) and intraventricular hemorrhagic grade (p < 0.001). As statistically significant predictors of the poor treatment outcome of the experimental group of patients treated by using Ommaya reservoir were identified: low body mass on birth (p < 0.05), low Apgar score (p < 0.05), prolonged number of days on assisted ventilation (p < 0.05), presence of peripartum asphyxia (p < 0.05) and cardiorespiratory arrest (p < 0.05). No statistically significant difference was detected in the outcome between the patients treated by the standard method and those with installed Ommaya reservoir. However, the difference of 10% in mortality between the two groups may be clinically significant so that further studies of larger samples are necessary.

Natural course of aneurysms that occur on blood vessels of the brain singles out the need for understanding the mechanism of the occurrence of aneurysm wall rupture and identification of anatomic characteristics as predictive factors for hemorrhage to occur. In this study we comparatively present results of our researches and experimental models on animals. We made a comparative analysis of anatomical characteristics of blood vessels of the brain and aneurysms obtained on the basis of digital subtraction angiography and intraoperative finding. In this article we review recent research in the anatomic characteristics of intracranial aneurysms and parent blood vessels. We present a series of 185 aneurysms (ruptured and unruptured) dissected at the Neurosurgical Clinic of Clinical Center of Serbia in Belgrade. Inclination angle may be considered as the vital predesposing factor for intracranial aneurysm rupture. In aneurysms that ruptured it was 139.748+/-27.242 degrees, while in unruptured aneurysms it was considerably smaller and amounted to 100.882+/-22.001 degrees (p<0.01). Inclination angle may be regarded as the vital predisposing factor since it differs considerably in unruptured and ruptured aneurysms. Aneurysms with blood stream angle smaller than 115 degrees have very small probability of rupture, while blood stream angle bigger than 150 degrees presents a high risk of rupture.

AVM because of outstanding tendency toward bleeding, even though 20 times more rare then aneurysm on the blood vessels of the brain and her own specific anatomical structure even today represents big neurosurgical challenge. MATERIAL and Series which is shown here consists of 39 patients which were hospitalized in the institute for neurosurgery of the Clinical Center of Serbia in the period between 1995 and 2004. This group was exposed to symptomatic therapy or it was estimated that surgery, embolization and radio surgery. Combined type of venous drainage brings a high risk (p < 0.001) from repeated bleeding. Combined artery bringing from different flows (p < 0.05) contributes to genesis of 'steal phenomenon', in combination with deep venous drainage it presents predisposing anatomical characteristics for repeated bleeding (p < 0.001) according to our results should present AVM with dimensions 2.5 to 5 cm localized in eloquent zone of big brain with combined type of venous drainage and cobined artery bringing from vertebro-basilar flow and carotid flow. Perception of natural course of AVM point to certainly more benign pathology in regard to other vascular malformations. Specific anatomical structure requires planning of treatment from case to case, most often combination of embolization, radio surgery and surgical treatment.

Therapeutic protoclol for intracranial aneurysm treatment is very complex. In depand od patient status and anviografic founding we determinate modality and time of treatment. Analysis included 137 patients who were treated in Neurosurgical clinic CCS because sponatenus subarachnoid haemorrhage rigine from aneurysm belading. We performed direct surgery (microsurgery) in 109 patients. In early termine we operated 28 patients (25.69%), in first 24 hours 5 of them. In interemdiate period we performed surgery in 9, and other 72 patient we operated in postpone period. Embolisation was performed in 22 patinet. GOS form embolised patient was 4.636 +/- 0.581 and in operated 4.113 +/- 1.106 (p < 0.05). Cumulative experient of Neurisurgical Clinic CCS and summation of international experience impose as the best treatment is the treatment which is best known for the physician.

Different clinical and surgical factors can influence the occurrence of anesthesiologic complications in pediatric neurosurgery. Preoperative knowledge of these factors is of great importance in the application of safe anesthetics and a favorable surgical outcome. The objective was to establish the importance of clinical and surgical risk factors on the frequency of anesthesia complications in pediatric neurosurgery. The research, from 1996 to 2000, involved 705 children, aged from <1 year to 15 years, who underwent surgery for elective neurosurgical pathology and severe head injuries. We analysed the influence that: age, the preoperative neurologic diagnosis, the urgency of the operation, additional disorders, the surgical position, and the duration of anesthesia had on the frequency of anesthesia complications. To test the statistical relevance and to confirm the hypothesis, the Pearson's chi-square test, Mann-Whitney U-test, and univariate and multivariate logistic regressions were used. Anesthesia complications (cardiovascular, respiratory, air embolism, allergic reactions) were present in 68/705 (9.6%) patients. Their frequency was statistically greater in children for whom the surgery was >240 min, who were in the sitting position and when comorbidity was evident. Neither age nor the urgency of the operation or reoperation had any significant influence on the occurrence of anesthetic complications. The duration of anesthesia, the sitting position of the patient, and the presence of comorbidities significantly increase the risk of anesthesia complications in pediatric neurosurgery.

The etiology of the noninflamed edema of the optic disc, or the stasis of the same, is related to a large number of various illnesses which result in the increased intracranial pressure. When examining fundus, an edema of the optic disc is found which can be quantitatively expressed in diopters, while retrobulbar part of the optic nerve can be measured by ultrasonography. The objective of our [Serbian characters: see text] is to explore the relation of the optic disc prominence and the degree of thickness of retrobulbar part of the optic nerve. Study included 21 patients with the increased intracranial pressure, treated at the Institute of Neurosurgery, Clinical Center of Serbia, that is, 41 eyes that manifested stasis of the optic nerve. Echographically, by means of Schraeder's method, the thickness of retrobulbar part of the optic nerve was measured and the degree of the optic disc prominence was clinically determined in diopters. The thickened optic nerve was confirmed in all patients. Using Pearson's correlation, the relation between the degree of the optic nerve thickness and the prominence of the same was analyzed, and it was found that there was no significant correlation between these two parameters. Instead of conclusion, we shall ask a question: How relevant is dogma that the prominence of the optic disc more than 3D should be considered the optic disc stasis? The authors think that rating of the optic disc prominence in diopters is not justified.

The use of computer models for the 3-dimensional reconstruction could be a reliable method to overcome technical imperfections of diagnostic procedures for the microsurgical operation of giant intracranial aneurysms. We presented a case of successfully operated 52-year-old woman with giant intracranial aneurysm, in which the computer 3-dimensional reconstruction of blood vessels and the aneurysmal neck had been decisive for making the diagnosis. The model for 3-dimensional reconstruction of blood vessels was based on the two 2-dimensional projections of the conventional angiography. Standard neuroradiologic diagnostic procedures showed a giant aneurysm on the left middle cerebral artery, but the conventional subtraction and CT angiography did not reveal enough information. By the use of a personal computer, we performed a 3-dimensional spatial reconstruction of the left carotid artery to visualize the neck of aneurysm and its supplying blood vessels. The 3-dimensional spatial reconstruction of the cerebral vessels of a giant aneurysm based on the conventional angiography could be useful for planning the surgical procedure.

Haemorrhage is most important sequelae of brain cavernoma, so the surgical treatment is very important for treatment that complication. There are two types of bleeding chronic subclinical microhaemorrhage and acute real haemorrhage. Pathophysiological factors wich are responsible for bleeding are not still understanding. The reason for this study is understanding of clinical curse of cavernomas and identification of factors of influence. This is retrospective and prospective study. We analised 36 patients with simpthomatic brain cavernoma, surgicaly treated in Institute of neurosurgery KCS in 10 years period (1987-1997). Female were dominant but without statistical significance (p > 0.05). Male patients were older (32,1:29,8), but without statistical significance (p > 0.05). Almost 75% lesions were supratentorial, 25% infratentorial (p < 0.05). Focal neurological deficite (FND) was dominant clinical presentation in 52.8%. FND was dominant in 52.6% female, but without statistical singnificans (p > 0.05). Clinical presentation according the age was not statisticaly significant (p > 0.05). Clinical presentation was very diferent according the size of lesion (p < 0.001). FND as a sign of bleeding was in 57.9% supratentorial cavernomas and in 42.1% infratentorial (p < 0.005). More than 1/3 patients have recurent bleeding with 21 atack of haemorrhage or almost 2 atack per patient. We find that dominant predictive factors for recurent haemorrhages are localisation and size of lesion.

To provide updated outcome data (10 years) of a Phase II study of combined surgery, postoperative radiotherapy, and adjuvant chemotherapy in patients with anaplastic oligodendroglioma and oligoastrocytoma. In 23 adult patients, surgery, postoperative radiotherapy (60 Gy in 30 daily fractions within 6 weeks), and adjuvant modified chemotherapy (procarbazine 60 mg/m(2) on Days 1-14, lomustine 100 mg/m(2) on Day 1, and vincristine 1.4 mg/m(2) [maximum 2 mg] on Days 1 and 8) were administered every 6 weeks for up to six cycles or until progression occurred. The median follow-up was 116 months for all patients. The median survival time was 118 months, and the 5-year and 10-year survival rate was 57% and 47%, respectively. The median time to tumor progression was 78 months, with a 5-year and 10-year progression-free survival rate of 52% and 39%, respectively. Gender, age, Karnofsky performance status, location, and histologic type did not influence survival. Patients with tumors <or=4 cm did better than those with tumors >4 cm (p = 0.0470), as did those with total tumor resection compared with those with subtotal tumor resection or biopsy only (p = 0.0024). Gender, Karnofsky performance status, location, and histologic type did not influence progression-free survival, but younger age (p = 0.0389), smaller tumor size (p = 0.0357), and more radical surgery (p = 0.0033) correlated positively with it. Acute high-grade (Grade 3 or worse) chemotherapy-related toxicity was mainly hematologic, with 3 patients (13%) experiencing acute Grade 4 toxicity. The results of this 10-year update confirmed that the trimodality approach is effective in patients with anaplastic oligodendroglioma and oligoastrocytoma.

To provide a 10-year update of hyperfractionated radiation therapy (Hfx RT) in adults with incompletely resected supratentorial low-grade glioma. A total of 37 patients were treated with 55 Gy in 50 fractions in 25 treatment days in 5 weeks to tumor plus 2 cm, and additional 17.6 Gy given in 16 fractions in 8 treatment days in 1.5 weeks to tumor plus 1 cm, (1.1 Gy twice daily). Total dose was 72.6 Gy in 66 fractions in 33 treatment days in 6.5 weeks. After a median follow-up time of 121 months for all patients, the median survival time (MST) for all 37 patients was 145 months, whereas 10-year survival rate was 67%. Median time to tumor progression (MTP) has not yet been attained, but 10-year progression-free survival (PFS) rate was 62%. There was no difference in survival or PFS regarding gender, age, location, site, size, CT enhancement, and histology; whereas lower KPS, higher neurologic status, and lesser extent of surgery had an adverse influence. Infield progression occurred in 15 (88%), whereas in only 2 (12%) patients, tumor progression was described as marginal. Brain necrosis has not been observed so far. Autopsy findings confirmed recurrent glioma and excluded post-RT necrosis in 14 (38%) patients. Of those, 7 (50%) patients had either Grade 3 (n = 4) or Grade 4 (n = 3) glioma. High-dose HFX RT is effective with mild to moderate toxicity. Further studies are warranted with more patients before testing it against standard fractionation RT in this patient population.