Transient acute hydrocephalus after aneurysmal subarachnoid hemorrhage and aneurysm embolization: a single-center experience.

PURPOSE: Acute hydrocephalus is a common complication after aneurysmal subarachnoid hemorrhage (aSAH). It can be self-limiting or require cerebrospinal fluid diversion. We aimed to determine the transient acute hydrocephalus (TAH) rate in patients with aSAH treated endovascularly and evaluate its predictive factors. METHODS: A retrospective review of 357 patients with aSAH who underwent endovascular treatment from March 2013 to December 2019 was performed. Clinical and radiographic data were analyzed and risk factors with potential significance for acute hydrocephalus were identified. We constructed a new risk score, the Drainage Or Transiency of Acute Hydrocephalus after Aneurysmal SAH (DOTAHAS) score, that may differentiate patients who would experience TAH from those needing surgical interventions. RESULTS: Acute hydrocephalus occurred in 129 patients (36%), out of whom in 66 patients (51%) it was self-limiting while 63 patients (49%) required external ventricular drainage placement. As independent risk factors for acute hydrocephalus, we identified older age, poor initial clinical condition, aSAH from posterior circulation, and the extent of cisternal and intraventricular hemorrhage. The following three factors were shown to predict acute hydrocephalus transiency and therefore included in the DOTAHAS score, ranging from 0 to 7 points: Hunt and Hess grade ≥ 3 (1 point), modified Fisher grade 4 (2 points), and Ventricular Hijdra Sum Score (vHSS) ≥ 6 (4 points). Patients scoring ≥ 3 points had significantly higher risk for EVD (P < 0.0001) than other patients. CONCLUSION: The newly developed DOTAHAS score can be useful in identifying patients with transient acute hydrocephalus. Further score evaluation is needed.

The visibility of the periventricular crossroads of pathways in preterm infants as a predictor of neurological outcome and occurrence of neonatal epileptic seizures.

AIM: To evaluate the relationship between the neurological outcome, neonatal epileptic seizures, and signal-intensity visibility of the frontal and parietal periventricular crossroads of pathways on brain magnetic resonance imaging (MRI) in preterm infants at term-equivalent age. METHODS: The study enrolled 48 preterm infants born between 2012 and 2016. The signal-intensity characteristics of the frontal and parietal periventricular crossroads were evaluated and classified into four grades. A non-favorable outcome was defined as a motor and functional disorder with developmental delay and/or cerebral palsy. RESULTS: Neonatal seizures, epilepsy, pathological EEG and brain ultrasound finding, and brain MRI abnormalities were mostly found in neonates with non-favorable outcomes. Visible frontal and parietal periventricular crossroads were associated with a normal neurologic outcome (P=0.0004; P=0.0009, respectively). Not-visible or slightly visible periventricular crossroads were associated with non-favorable outcomes in the case of frontal crossroads (P=0.036) and not-visible periventricular crossroads in the case of both frontal and parietal crossroads (P=0.001, P=0.015, respectively). The visibility of the frontal and parietal periventricular crossroads was associated with a lack of neonatal epileptic seizures (P=0.03; P=0.02, respectively). The frontal crossroads were more frequently slightly visible, while the parietal periventricular crossroads were more frequently visible. CONCLUSION: Poor visibility of the frontal and parietal crossroads of pathways on MRI is associated with neonatal epileptic seizures and poor neurological outcomes in preterm infants at term-equivalent age.

Comparison between stenting and conservative management of posterior circulation perforator aneurysms: Systematic review and case series.

PURPOSE: Posterior circulation perforator aneurysms (PCPAs) are a rare type of intracranial aneurysms whose natural history and optimal clinical management are still largely unexplored. This study aims to report our experience with treating ruptured PCPAs and to provide a systematic review of the literature to compare the two most established treatment options, endovascular stenting, and conservative management including administration of antifibrinolytic drugs and watchful waiting. METHODS: We performed a systematic review of the literature following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Major databases were searched for case reports and case report series written in the English language between 1995 and 2020. Additionally, we retrospectively reviewed our stroke center database for cases of ruptured PCPAs between January 2014 and July 2020. Endovascular stenting and conservative treatment were compared using endpoints, including favorable outcome rate (mRS 0-2), occlusion rate, mortality rate, periinterventional complication rate, and re-hemorrhage rate. RESULTS: We identified 31 patients treated endovascularly using stents and 33 patients treated conservatively, with the administration of antifibrinolytic drugs in 3 of them. Our analysis showed no statistically significant difference between the groups, except for the occlusion rate. CONCLUSIONS: The optimal management strategy of PCPAs is still unknown, but stenting can be considered as an effective occlusion method with an acceptable complication rate. Preventive ventricular drainage may be necessary due to the high hydrocephalus rate encountered in ruptured PCPAs.

Choline elevation in amygdala region at recovery indicates longer survival without depressive episode: a magnetic resonance spectroscopy study.

RATIONALE: Depression, with variable longitudinal patterns, recurs in one third of patients. We lack useful predictors of its course/outcome, and proton magnetic resonance spectroscopy (1H-MRS) of brain metabolites is an underused research modality in finding outcome correlates. OBJECTIVES: To determine if brain metabolite levels/changes in the amygdala region observed early in the recovery phase indicate depression recurrence risk in patients receiving maintenance therapy. METHODS: Forty-eight patients on stable-dose antidepressant (AD) maintenance therapy were analyzed from recovery onset until (i) recurrence of depression or (ii) start of AD discontinuation. Two 1H-MRS scans (6 months apart) were performed with a focus on amygdala at the beginning of recovery. N-acetylaspartate (NAA), choline-containing metabolites (Cho), and Glx (glutamine/glutamate and GABA) were evaluated with regard to time without recurrence, and risks were assessed by Cox proportional hazard modeling. RESULTS: Twenty patients had depression recurrence, and 23 patients reached AD discontinuation. General linear model repeated measures analysis displayed three-way interaction of measurement time, metabolite level, and recurrence on maintenance therapy, in a multivariate test, Wilks' lambda = 0.857, F(2,40) = 3.348, p = 0.045. Cho levels at the beginning of recovery and subsequent changes convey the highest risk for earlier recurrence. Patients experiencing higher amygdala Cho after recovery are at a significantly lower risk for depression recurrence (hazard ratio = 0.32; 95% confidence interval 0.13-0.77). CONCLUSION: Cho levels/changes in the amygdala early in the recovery phase correlate with clinical outcome. In the absence of major NAA fluctuations, changes in Cho and Glx may suggest a shift towards reduction in (previously increased) glutamatergic neurotransmission. Investigation of a larger sample with greater sampling frequency is needed to confirm the possible predictive role of metabolite changes in the amygdala region early in the recovery phase.

Acute Carotid Stent Thrombosis in an Ultrarapid Clopidogrel Metabolizer: Case Report and Literature Review.

INTRODUCTION: Carotid angioplasty and stenting (CAS) represents an effective procedure for treating carotid artery disease. The acute in-stent thrombosis is an extremely rare complication of CAS especially when it occurs postprocedurally during the first 24 hours. Improper antiplatelet therapy or poor response to antiplatelet medications is known to be associated with a higher risk of in-stent thrombosis during early postprocedural period following a successful intervention. MATERIAL AND METHODS: A patient who experienced acute carotid in-stent thrombosis in early postprocedural period is described. He had been taking dual antiplatelet therapy for 2 weeks before undergoing a successful CAS. Moreover, pharmacogenetics studies showed the patient to be a clopidogrel ultrarapid metabolizer, which theoretically confers hyperresponsivity to medication. Alongside the report itself, a brief literature review of relevant sources pertinent to the case has been conducted. RESULTS: According to the available literature, this is the first case report describing an ultrarapid clopidogrel metabolizer who underwent an uneventful CAS but experienced acute carotid in-stent thrombosis in early postprocedural period. A rescue procedure included an endovascular intervention consisting of thrombectomy and local alteplase application, followed by postprocedural administration of intravenous eptifibatide. At discharge, patient's dual antiplatelet therapy included ticagrelor instead of clopidogrel. CONCLUSION: Acute carotid in-stent thrombosis is a highly unexpected complication of CAS and can occur despite ultrarapid clopidogrel metabolism trait.

The physiological range of the Böhler's angle in the adult Croatian population.

BACKGROUND: To examine the relationship of the Böhler's angle with age, sex, and laterality, and to analyze the interrater agreement. METHODS: After 248 digital lateral radiographs of the foot were submitted to exclusion criteria, three raters independently measured the Böhler's angle on the remaining 130 X-rays in PACS. The variables were analyzed with correlation coefficients, and one-way ANOVA. The repeated measures of ANOVA were computed across age groups (30-39, 40-49, 50-59, and 60-69 years). The interrater agreement was calculated using intraclass correlation coefficient (ICC). RESULTS: The mean value of the Böhler's angle was 34±5° (21-46°). It was not related to age (in general [p=0.057], and across groups [p from 0.107 to 0.122]), sex (p=0.344; p=0.342), and laterality (p=0.618; p=0.617). The interrater reliability was almost perfect (ICC=0.94). CONCLUSIONS: The Böhler's angle was not related to age, sex, and laterality, whereas the interrater agreement was almost perfect.

Impact of remote ischemic preconditioning preceding coronary artery bypass grafting on inducing neuroprotection.

BACKGROUND: Neurological complications after coronary artery bypass grafting (CABG) reduce quality of life, increase mortality, and inflate resource utilization. The risk of postoperative neurological complications parallels the increasing risk burden of the contemporary patient population. We evaluated the efficacy of remote ischemic preconditioning (RIPC) on inducing neuroprotection. METHODS: Seventy patients undergoing first-time CABG were randomly assigned to RIPC or a sham procedure. Structural brain magnetic resonance imaging (MRI) was complemented with functional connectivity MRI to gain a whole-brain global connectivity analysis. Paired neurocognitive and MRI data were acquired pre- and postoperatively. The primary end point was a composite of new ischemic brain lesions and neurocognitive impairment. Secondary end points included brain connectivity profiles, pooled ischemic volumes, and individual components of the primary outcome. The Shapiro-Wilk test was used to determine whether a data set followed a normal distribution. The Fisher exact test was used to calculate the measures of association for categorical variables, whereas continuous data were tested with either the Mann-Whitney U test or the Student t test. RESULTS: There was no between-group difference in the incidence of the primary end point (9 [27%] in the RIPC group vs 8 [24%] in the control group, odds ratio, 1.17 [95% confidence interval, 0.34-4.06]; P = 1.0). Although RIPC did not reduce the incidence of brain ischemia (8/33 [24%] vs 7/33 [21%]; P = 1.0), the pooled ischemic volume was lower in the RIPC group (157 [interquartile range, 125-231] vs 777 [interquartile range, 564-965] mm3; P = .004). Postoperative neurocognition was marginally superior in the RIPC group as evidenced by a lower absolute number of abnormal neurocognitive tests in the RIPC group (7/99 [7%] vs 16/99 [16%]; odds ratio, 0.40 [95% confidence interval, 0.14-1.09]; P = .074). Robust reductions of functional connectivity profiles for the associative thalamus were documented in both groups, irrespective of RIPC (RIPC group, t = 3.31; P < .01; and the control group, t = 3.52; P < .01). CONCLUSIONS: Silent brain ischemia occurs frequently after CABG. RIPC did not reduce the incidence of the primary outcome. However, RIPC significantly reduced the pooled volume of ischemic brain lesions. Surgery adversely affected global brain connectivity, with RIPC conferring no demonstrable protection. The association of RIPC with superior neurocognitive test scores failed to cross the threshold for significance.

Choline and N-acetyl aspartate levels in the dorsolateral prefrontal cortex at the beginning of the recovery phase as markers of increased risk for depressive episode recurrence under different duration of maintenance therapy and after it: a retrospective cohort study.

AIM: To evaluate the relationship between the dynamics of proton magnetic resonance spectroscopy (1H-MRS) brain metabolite levels at the beginning of the recovery phase of the index depressive episode and the time to the recurrence of depression. METHODS: This retrospective cohort study analyzed the changes in N-acetyl aspartate (NAA), choline (Cho), and glutamate-glutamine in 48 patients with recurrent depression treated with maintenance antidepressant monotherapy at a stable dose. 1H-MRS was performed at the start of the recovery phase and 6 months later. 1H-MRS parameters, index episode descriptors, and depressive disorder course were analyzed by Cox proportional hazards model. RESULTS: NAA and Cho decrease six months after the beginning of the recovery period were time-independent risk factors for depressive episode recurrence. Hazard ratio associated with NAA decrease was 2.02 (95% confidence interval 1.06-3.84) and that associated with Cho decrease was 2.06 (95% confidence interval 1.02-4.17). These changes were not related to symptoms severity, as Montgomery-Asberg Depression Scale score remained generally unchanged (mean -0.01; standard deviation 1.6) over the first 6 months of recovery. CONCLUSION: Patients receiving maintenance antidepressant therapy after recovery who experience a decrease in NAA or Cho levels early in the recovery phase have a double risk of depressive episode recurrence. Sustained NAA and Cho levels at the beginning of the recovery phase may indicate increased brain resilience conferred by antidepressant therapy, while NAA and Cho decrease may indicate only the trait-related temporal effect of therapy in another stratum of patients.

Interactive histogenesis of axonal strata and proliferative zones in the human fetal cerebral wall.

Development of the cerebral wall is characterized by partially overlapping histogenetic events. However, little is known with regards to when, where, and how growing axonal pathways interact with progenitor cell lineages in the proliferative zones of the human fetal cerebrum. We analyzed the developmental continuity and spatial distribution of the axonal sagittal strata (SS) and their relationship with proliferative zones in a series of human brains (8-40 post-conceptional weeks; PCW) by comparing histological, histochemical, and immunocytochemical data with magnetic resonance imaging (MRI). Between 8.5 and 11 PCW, thalamocortical fibers from the intermediate zone (IZ) were initially dispersed throughout the subventricular zone (SVZ), while sizeable axonal "invasion" occurred between 12.5 and 15 PCW followed by callosal fibers which "delaminated" the ventricular zone-inner SVZ from the outer SVZ (OSVZ). During midgestation, the SS extensively invaded the OSVZ, separating cell bands, and a new multilaminar axonal-cellular compartment (MACC) was formed. Preterm period reveals increased complexity of the MACC in terms of glial architecture and the thinning of proliferative bands. The addition of associative fibers and the formation of the centrum semiovale separated the SS from the subplate. In vivo MRI of the occipital SS indicates a "triplet" structure of alternating hypointense and hyperintense bands. Our results highlighted the developmental continuity of sagittally oriented "corridors" of projection, commissural and associative fibers, and histogenetic interaction with progenitors, neurons, and glia. Histogenetical changes in the MACC, and consequently, delineation of the SS on MRI, may serve as a relevant indicator of white matter microstructural integrity in the developing brain.

Tentorial alignment and its relationship to cisternal dimensions of the pineal region: MRI anatomical study with surgical implications using the new clivotentorial method.

OBJECTIVES: Tentorial alignment and dimensions of posterior fossa cisterns are measurements whose variability can decrease surgical freedom if not taken into account when choosing the approach to the pineal region. The aim is to provide quantitative anatomical information regarding these dimensions, and to discuss their relevance in two most commonly used approaches to this region: the occipital transtentorial and supracerebellar-infratentorial approach. PATIENTS AND METHODS: A retrospective study of midsagittal T1-weighted MRI images of 410 randomly selected healthy subjects was performed. The clivus-tentorium (C-T) angle was measured to assess tentorial alignment. The following distances were used as craniocaudal cisternal measurements: quadrigeminal cistern = superior colliculi - inferior part of the splenium of corpus callosum (SC-ISCC), and superior cerebellar cistern = vermis - inferior part of the splenium of corpus callosum (VER-ISCC). RESULTS: Median C-T angle value was 19 ±â€¯7°, the quadrigeminal cistern height 6.7 ±â€¯1.6 cm, and the superior cerebellar cistern height 10.4 ±â€¯2.6 cm. The C-T angle was negatively correlated with the SC-ISCC distance (r = -0.271; p <  0.001) and the VER-ISCC distance (r = -0.052, p >  0.001). The SC-ISCC distance was positively correlated with the VER-ISCC distance (r = 0.282; p < 0.001). CONCLUSION: Our new method of measuring tentorial alignment provides a simple and effective aid in preoperative planning. For the first time, we present data on craniocaudal dimensions of posterior fossa cisterns, their relationship with tentorial alignment, and discuss their relevance in SCIT and OT approaches.

Lower Choline-Containing Metabolites/Creatine (Cr) Rise and Failure to Sustain NAA/Cr Levels in the Dorsolateral Prefrontal Cortex Are Associated with Depressive Episode Recurrence under Maintenance Therapy: A Proton Magnetic Resonance Spectroscopy Retrospective Cohort Study.

BACKGROUND: The aim of this study was to evaluate the relationship between changes in proton magnetic resonance spectroscopy (1H-MRS) parameters at the start of the index episode recovery phase and at recurrence in patients with recurrent depression who were treated with prolonged maintenance therapy. METHODS: 1H-MRS parameters were analyzed in 48 patients with recurrent depression who required maintenance therapy with antidepressant medication prescribed by a psychiatrist and who continued with the same antidepressant during the maintenance phase, either to recurrence of depression, completion of the 10-year observation period, or the start of the withdrawal phase (tapering-off antidepressant). N-acetylaspartate (NAA), choline-containing metabolites (Cho), creatine (Cr), and glutamine/glutamate were measured at the start of the recovery phase and 6 months later. RESULTS: Recurrent depressive episodes occurred in 20 patients. These individuals had a smaller increase in Cho/Cr after the beginning of the recovery phase compared to the non-recurrent patient group and also exhibited a decreased NAA/Cr ratio. CONCLUSION: Sustainable NAA and increased Cho levels at the onset of the recovery phase of the index episode are early markers of antidepressant effectiveness associated with a lower risk of major depressive disorder recurrence. The NAA and Cho changes in the non-recurrent group may be attributable to increased brain resilience, contrary to the transient temporal effect observed in subjects who experienced a depressive episode.

Long-term angiographic outcome of stent-assisted coiling compared to non-assisted coiling of intracranial saccular aneurysms.

AIM: To compare angiographic result at long-term follow-up, and rates of progressive occlusion, recurrence, and retreatment of stent-assisted coiled (SAC) and non-assisted coiled (NAC) intracranial saccular aneurysms. METHODS: Retrospective evaluation of department records identified 260 patients with 283 saccular intracranial aneurysms who had long-term angiographic follow-up (more than 12 months) and were successfully treated with SAC (89 aneurysms) or NAC (194 aneurysms) at the University Hospital Center Zagreb from June 2005 to July 2012. Initial and control angiographic results in both groups were graded using Roy/Raymond scale, converted to descriptive terms, and the differences between them were evaluated for statistical significance. A multivariate analysis was performed to identify factors related to progression of aneurysm occlusion and recurrence at follow-up, and those related to aneurysm retreatment. RESULTS: There were more progressively occluded aneurysms in SAC group (38 of 89 aneurysms, 42.7%) than in NAC group (46 of 194, 23.7%) (P=0.002), but there were no significant differences in the rates of recanalization, regrowth, and stable result. Multivariate logistic regression identified the use of stent as the most important factor associated with progressive occlusion (P=0.015, odds ratio 2.22, 95% confidence interval 1.17-4.21), and large aneurysm size and posterior circulation location as most predictive of aneurysm recurrence and retreatment. CONCLUSION: The use of stent is associated with delayed occlusion of initially incompletely coiled aneurysms during follow-up, but does not reduce the rate of recurrence and retreatment compared to coiling alone. Long-term angiographic follow-up is needed for both SAC and NAC aneurysms.

[CLINICAL GUIDELINES FOR DIAGNOSING, TREATING AND MONITORING OF ADULT PATIENTS WITH GLIOMAS OF CENTRAL NERVOUS SYSTEM]. / KLINICKE UPUTE ZA DIJAGNOZU, LIJECENJE I PRACENJE ODRASLIH BOLESNIKA OBOLJELIH OD GLIOMA SREDISNJEGA ZIVCANOG SUSTAVA.

Gliomas of the central nervous system are glial cell tumors that are divided in low and high grade group. Multidisciplinary approach to treatment consists of surgery, radiotherapy and chemotherapy. The type and order of treatment depend on the characteristics of the tumor and the patient. We present the clinical guidelines for diagnostic procedures, surgical treatment, oncological treatment and follow up of patients with this type of tumor in the Republic of Croatia.

No change in N-acetyl aspartate in first episode of moderate depression after antidepressant treatment: (1)H magnetic spectroscopy study of left amygdala and left dorsolateral prefrontal cortex.

BACKGROUND: The role of brain metabolites as biological correlates of the intensity, symptoms, and course of major depression has not been determined. It has also been inconclusive whether the change in brain metabolites, measured with proton magnetic spectroscopy, could be correlated with the treatment outcome. METHODS: Proton magnetic spectroscopy was performed in 29 participants with a first episode of moderate depression occurring in the left dorsolateral prefrontal cortex and left amygdala at baseline and after 8 weeks of antidepressant treatment with escitalopram. The Montgomery-Asberg Depression Rating Scale, the Hamilton Rating Scale for Depression, and the Beck Depression Inventory were used to assess the intensity of depression at baseline and at the endpoint of the study. At endpoint, the participants were identified as responders (n=17) or nonresponders (n=12) to the antidepressant therapy. RESULTS: There was no significant change in the N-acetyl aspartate/creatine ratio (NAA/Cr) after treatment with antidepressant medication. The baseline and endpoint NAA/Cr ratios were not significantly different between the responder and nonresponder groups. The correlation between NAA/Cr and changes in the scores of clinical scales were not significant in either group. CONCLUSION: This study could not confirm any significant changes in NAA after antidepressant treatment in the first episode of moderate depression, or in regard to therapy response in the left dorsolateral prefrontal cortex or left amygdala. Further research is necessary to conclude whether NAA alterations in the first episode of depression could possibly be different from chronic or late-onset depression, and whether NAA alterations in stress-induced (reactive) depression are different from endogenous depression. The potential role of NAA as a biomarker of a treatment effect has yet to be established.

Impact of remote ischemic preconditioning preceding coronary artery bypass grafting on inducing neuroprotection (RIPCAGE): study protocol for a randomized controlled trial.

BACKGROUND: Neurological complications after cardiac surgery have a profound impact on postoperative survival and quality of life. The increasing importance of strategies designed to improve neurological outcomes mirrors the growing risk burden of the contemporary cardiac surgical population. Remote ischemic preconditioning (RIPC) reduces adverse sequelae of ischemia in vulnerable organs by subjecting tissues with high ischemic tolerance to brief periods of hypoperfusion. This trial will evaluate the neuroprotective effect of RIPC in the cardiac surgical arena, by employing magnetic resonance imaging (MRI) and neurocognitive testing. METHODS: Patients scheduled for elective coronary artery bypass grafting with the use of cardiopulmonary bypass will be screened for the study. Eligible patients will be randomized to undergo either a validated RIPC protocol or a sham procedure. The RIPC will be induced by inflation of a blood pressure cuff to 200 mmHg for 5 minutes, followed by a 5-minute reperfusion period. Three sequences of interchanging cuff inflations and deflations will be employed. Neurocognitive testing and MRI imaging will be performed preoperatively and on postoperative day 7. Paired pre- and postoperative neurocognitive and neuroimaging data will then be compared. The primary composite outcome measure will consist of new ischemic lesions on brain MRI, postprocedural impairment in brain connectivity on resting-state functional MRI (rs-fMRI), and significant new declines in neurocognitive performance. The secondary endpoint measures will be the individual components of the primary endpoint measures, expressed as continuous variables, troponin T release on postoperative day 1 and the incidence of major adverse cardiovascular events at 3 months postoperatively. Major adverse cardiovascular events, including accumulating cardiovascular mortality, stroke, nonfatal myocardial infarction, and rehospitalization for ischemia, will form a composite endpoint measure. DISCUSSION: This trial will aim to assess whether RIPC in patients subjected to surgical myocardial revascularization employing cardiopulmonary bypass initiates a neuroprotective response. Should the results of this trial indicate that RIPC is effective in reducing the incidence of adverse neurological events in patients undergoing coronary artery bypass grafting, it could impact on the current standard of care. TRIAL REGISTRATION: ClinicalTrials.gov NCT02177981.

Long lasting near-obstruction stenosis of mesencephalic aqueduct without development of hydrocephalus--case report.

The aim of this study is to present the five-year longitudinal magnetic resonance imaging (MRI) follow up of a patient with incidental finding of near-obstruction stenosis of the aqueduct of Sylvius due to a large pineal cyst. The patient was scanned 3 times on a 3T MR device using a set of standard structural sequences supplemented with high-resolution constructive interference of steady state (CISS) T2 sequence for precise delineation of the aqueduct of Sylvius and cardiac-gated phase-contrast sequences for the analysis of cerebrospinal fluid (CSF) movement. On all MR scans, the size of the pineal cyst and severity of near-obstruction aqueductal stenosis did not show any morphological changes. There was no significant ventricular enlargement although structural CISS sequence showed a near-obstruction stenosis and cardiac-gated phase-contrast sequences did not detect CSF movement through the aqueduct of Sylvius. Our findings are contradictory to the classic hypothesis of CSF physiology based on secretion, circulation, and absorption of CSF, which states that the impairment of CSF circulation through the aqueduct of Sylvius inevitably leads to a hypertensive hydrocephalus development involving the third and the lateral ventricle. Our research group previously proposed a new hypothesis of CSF physiology, which offers more suitable explanation for such clinical cases.

The effect of atypical antipsychotics on brain N-acetylaspartate levels in antipsychotic-naïve first-episode patients with schizophrenia: a preliminary study.

PURPOSE: To investigate the correlates of a clinical therapeutic response by using the parameters measured by proton magnetic resonance spectroscopy after the administration of atypical antipsychotics. PATIENTS AND METHODS: Twenty-five antipsychotic-naïve first-episode patients with schizophrenia were monitored for 12 months. The patients were evaluated using (1)H magnetic resonance spectroscopy in the dorsolateral prefrontal cortex and Positive and Negative Syndrome Scale, Clinical Global Impression Scale of Severity, Tower of London - Drexel University, Letter-Number Span Test, Trail Making Test A, and Personal and Social Performance Scale. They were administered atypical antipsychotics, starting with quetiapine. In the absence of a therapeutic response, another antipsychotic was introduced. RESULTS: After 12 study months, the N-acetylaspartate/creatine (NAA/Cr) level did not significantly change at the whole-group level. Additional analysis revealed a significant rise in the NAA/Cr level in the study group that stayed on the same antipsychotic throughout the study course (P=0.008) and a significant drop in NAA/Cr in the study group that switched antipsychotics (P=0.005). On the whole-group level, no significant correlations between NAA/Cr values and other scores were found at either baseline or after 12 study months. CONCLUSION: One-year treatment with atypical antipsychotics administered to antipsychotic-naïve patients didn't result in a significant rise in the NAA/Cr ratio. However, a significant rise was witnessed in the study group in which a satisfactory therapeutic response had been achieved with a single antipsychotic administration.

General recommendations for the management of aneurysmal subarachnoid hemorrhage.

Subarachnoid hemorrhage is a neurologic emergency and a detrimental cerebrovascular event with a high rate of death and complications. Recommendations have been developed and based on literature search, evaluation of the results of large international clinical trials, collective experience of the authors, and endorsed by the Croatian Society of Neurovascular Disorders, Croatian Society of Neurology including Section for Neurocritical Care, Croatian Neurosurgical Society, Croatian Society for Difficult Airway Management and Croatian Medical Association. The aim of these guidelines is to provide current and comprehensive recommendations and to assist physicians in making appropriate decisions in the management of subarachnoid hemorrhage. Evidence based information on the epidemiology, risk factors and prognosis, as well as recommendations on diagnostic work up, monitoring and management are provided, with regard to treatment possibilities in Croatia.