Publications by authors named "Darko Chudy"

26 Publications

  • Page 1 of 1

Structural changes in brains of patients with disorders of consciousness treated with deep brain stimulation.

Sci Rep 2021 Feb 23;11(1):4401. Epub 2021 Feb 23.

Department of Neurosurgery, Dubrava University Hospital, Avenija Gojka Suska 6, 10000, Zagreb, Croatia.

Disorders of consciousness (DOC) are one of the major consequences after anoxic or traumatic brain injury. So far, several studies have described the regaining of consciousness in DOC patients using deep brain stimulation (DBS). However, these studies often lack detailed data on the structural and functional cerebral changes after such treatment. The aim of this study was to conduct a volumetric analysis of specific cortical and subcortical structures to determine the impact of DBS after functional recovery of DOC patients. Five DOC patients underwent unilateral DBS electrode implantation into the centromedian parafascicular complex of the thalamic intralaminar nuclei. Consciousness recovery was confirmed using the Rappaport Disability Rating and the Coma/Near Coma scale. Brain MRI volumetric measurements were done prior to the procedure, then approximately a year after, and finally 7 years after the implementation of the electrode. The volumetric analysis included changes in regional cortical volumes and thickness, as well as in subcortical structures. Limbic cortices (parahippocampal and cingulate gyrus) and paralimbic cortices (insula) regions showed a significant volume increase and presented a trend of regional cortical thickness increase 1 and 7 years after DBS. The volumes of related subcortical structures, namely the caudate, the hippocampus as well as the amygdala, were significantly increased 1 and 7 years after DBS, while the putamen and nucleus accumbens presented with volume increase. Volume increase after DBS could be a result of direct DBS effects, or a result of functional recovery. Our findings are in accordance with the results of very few human studies connecting DBS and brain volume increase. Which mechanisms are behind the observed brain changes and whether structural changes are caused by consciousness recovery or DBS in patients with DOC is still a matter of debate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-83873-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7902623PMC
February 2021

The Accuracy of Direct Targeting Using Fusion of MR and CT Imaging for Deep Brain Stimulation of the Subthalamic Nucleus in Patients with Parkinson's Disease.

J Neurol Surg A Cent Eur Neurosurg 2021 Feb 22. Epub 2021 Feb 22.

Department of Neurosurgery, Clinical Hospital Dubrava, Zagreb, Croatia.

Introduction:  In 33 consecutive patients with Parkinson's disease (PD) undergoing awake deep brain stimulation (DBS) without microelectrode recording (MER), we assessed and validated the precision and accuracy of direct targeting of the subthalamic nucleus (STN) using preoperative magnetic resonance imaging (MRI) and stereotactic computed tomography (CT) image fusion combined with immediate postoperative stereotactic CT and postoperative MRI, and we report on the side effects and clinical results up to 6 months' follow-up.

Materials And Methods:  Preoperative nonstereotactic MRI and stereotactic CT images were merged and used for planning the trajectory and final lead position. Immediate postoperative stereotactic CT and postoperative nonstereotactic MRI provided the validation of the final electrode position. Changes in the Unified Parkinson's Disease Rating Scale III (UPDRS III) scores and the levodopa equivalent daily doses (LEDD) and appearance of adverse side effects were assessed.

Results:  The mean Euclidian distance (ED) error between the planned position and the final position of the lead in the left STN was 1.69 ± 0.82 mm and that in the right STN was 2.12 ± 1.00. The individual differences between planned and final position in each of the three coordinates were less than 2 mm. The UPDRS III scores improved by 75% and LEDD decreased by 45%. Few patients experienced complications, such as postoperative infection (= 1), or unwanted side effects, such as emotional instability ( = 1).

Conclusion:  Our results confirm that direct targeting of an STN on stereotactic CT merged with MRI could be a valid method for placement the DBS electrode. The magnitude of our targeting error is comparable with the reported errors when using MER and other direct targeting approaches.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1055/s-0040-1715826DOI Listing
February 2021

Frameless stereotactic brain biopsy: A prospective study on robot-assisted brain biopsies performed on 32 patients by using the RONNA G4 system.

Int J Med Robot 2021 Feb 16. Epub 2021 Feb 16.

Department of Neurosurgery, University Hospital Dubrava, Zagreb, Croatia.

Background: We present a novel robotic neuronavigation system (RONNA G4), used for precise preoperative planning and frameless neuronavigation, developed by a research group from the University of Zagreb and neurosurgeons from the University Hospital Dubrava, Zagreb, Croatia. The aim of study is to provide comprehensive error measurement analysis of the system used for the brain biopsy.

Methods: Frameless stereotactic robot-assisted biopsies were performed on 32 consecutive patients. Post-operative CT and MRI scans were assessed to precisely measure and calculate target point error (TPE) and entry point error (EPE).

Results: The application accuracy of the RONNA system for TPE was 1.95 ± 1.11 mm, while for EPE was 1.42 ± 0.74 mm. The total diagnostic yield was 96.87%. Linear regression showed statistical significance between the TPE and EPE, and the angle of the trajectory on the bone.

Conclusion: The RONNA G4 robotic system is a precise and highly accurate autonomous neurosurgical assistant for performing frameless brain biopsies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/rcs.2245DOI Listing
February 2021

Stereotactic Neuro-Navigation Phantom Designs: A Systematic Review.

Front Neurorobot 2020 23;14:549603. Epub 2020 Oct 23.

Department of Neurosurgery, University Hospital Dubrava, Zagreb, Croatia.

Diverse stereotactic neuro-navigation systems are used daily in neurosurgery and novel systems are continuously being developed. Prior to clinical implementation of new surgical tools, methods or instruments, experiments on phantoms should be conducted. A stereotactic neuro-navigation phantom denotes a rigid or deformable structure resembling the cranium with the intracranial area. The use of phantoms is essential for the testing of complete procedures and their workflows, as well as for the final validation of the application accuracy. The aim of this study is to provide a systematic review of stereotactic neuro-navigation phantom designs, to identify their most relevant features, and to identify methodologies for measuring the target point error, the entry point error, and the angular error (α). The literature on phantom designs used for evaluating the accuracy of stereotactic neuro-navigation systems, i.e., robotic navigation systems, stereotactic frames, frameless navigation systems, and aiming devices, was searched. Eligible articles among the articles written in English in the period 2000-2020 were identified through the electronic databases PubMed, IEEE, Web of Science, and Scopus. The majority of phantom designs presented in those articles provide a suitable methodology for measuring the target point error, while there is a lack of objective measurements of the entry point error and angular error. We identified the need for a universal phantom design, which would be compatible with most common imaging techniques (e.g., computed tomography and magnetic resonance imaging) and suitable for simultaneous measurement of the target point, entry point, and angular errors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnbot.2020.549603DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7644893PMC
October 2020

Hemoglobin A1c in Patients with Glioblastoma-A Preliminary Study.

World Neurosurg 2020 09 31;141:e553-e558. Epub 2020 May 31.

Department of Neurosurgery, Clinical Hospital Dubrava, Zagreb, Croatia; Department of Surgery, Zagreb University School of Medicine, Zagreb, Croatia.

Background: Glioblastomas are among the most common primary brain tumors with an abysmal prognosis. The significance of glucose metabolism in glioblastoma cell metabolism and proliferation is well-known. However, a significant correlation between the systemic metabolic status of the patient and the cellular proliferation of the glioblastoma has not yet been established.

Methods: Our aim was to observe and analyze for a possible correlation between glioblastoma cellular proliferation and patients' glycated hemoglobin (HbA1c) levels as a marker of chronic systemic glycemia. We analyzed the data from 25 patients and compared their Ki-67 values with their preoperative HbA1c values.

Results: We observed a statistically significant correlation (P < 0.03) between chronic glycemia (measured using HbA1c) and the cellular proliferation of glioblastoma (measured by cellular Ki-67 expression).

Conclusions: These results imply a possible positive correlation between glioblastoma cell proliferation and chronic systemic glycemia, a correlation that, to the best of our knowledge, has not yet been reported. Further research in this area could not only lead to a better understanding of glioblastoma but also have significant clinical applications in treating this devastating disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wneu.2020.05.231DOI Listing
September 2020

A biphasic tumor in posterior cranial fossa and the pineal region in young adult.

Surg Neurol Int 2020 11;11:64. Epub 2020 Apr 11.

Departments of Neurosurgery, University Hospital Dubrava, Zagreb, Croatia.

Background: Biphasic tumors of the central nervous system are rarely described and mainly consisted out of the glial and mesenchymal component. The tumor originated out of both astrocytes and pinealocytes, best to our knowledge, has not been described. We present a case of a brain tumor consisted out of pilocytic astrocytoma (PA) and pineocytoma as components situated in the pineal region and posterior cranial fossa in young adult.

Case Description: We present a 21-year-old patient with a history of intermittent headache, followed by nausea and vomiting, double vision, and dextropulsion. Magnetic resonance imaging revealed an extensive cystic-solid expansive formation in the posterior cranial fossa with a solid part in the area of the pineal gland. The patient underwent surgical resection. The pathohistological analysis showed two types of tumor cells; the major part of tumor showed features of PA, while minor part corresponded to pineocytoma.

Conclusion: PA accounts for 5% of all gliomas and is most common in children and young adults. It usually occurs in the cerebellum, the optic pathway, third ventricular region, etc. Pineocytomas are rare, accounting up to 1% of all intracranial tumors. Since tumors origin is different, there must be complex molecular events or mutations that can lead to cell rearrangements and generation of two histologically different tissues in the same tumor mass. The course of treatment options is different for PA and pineocytoma; therefore, the case of brain mass consisted out of two different tissues can be helpful when deciding about the treatment of tumors in posterior cranial fossa and pineal region.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.25259/SNI_288_2019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7193197PMC
April 2020

HbA1c in patients with intracranial meningiomas WHO grades I and II: A preliminary study.

IUBMB Life 2020 07 5;72(7):1426-1432. Epub 2020 Mar 5.

Department of Neurosurgery, Clinical Hospital Dubrava, Zagreb, Croatia.

Meningiomas are among the most common primary brain tumors. There is a growing need for novel ways of differentiating between benign (World Health Organization [WHO] grade I) and atypical (WHO grade II) meningiomas as well as for novel markers of the tumor's future behavior. A difference between glucose metabolism in atypical and benign meningiomas is well known. However, a significant correlation between the systemic metabolic status of the patient and the meningioma WHO grade has not yet been established. Our aim was to compare the WHO grades of intracranial meningiomas with the patient's HbA1c levels as a more reliable marker of the chronic systemic metabolic status than the fasting blood glucose value, which is usually looked at. We retrospectively analyzed 15 patients and compared their meningioma WHO grade with their preoperative HbA1c values. Our results show that patients with benign intracranial meningiomas have significantly lower HbA1c value. Conversely, patients with atypical intracranial meningiomas have higher HbA1c values. Furthermore, we showed that the proliferation factor Ki67 was statistically strongly correlated with the HbA1c value (p < .001. These results imply a possible positive correlation between meningioma cell proliferation and the chronic systemic glycemia. Further research in this area could not only lead to better understanding of meningiomas but could have significant clinical application.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/iub.2268DOI Listing
July 2020

The Dubrava Model-A Novel Approach in Treating Acutely Neurotraumatized Patients in Rural Areas: A Proposal for Management.

J Neurosci Rural Pract 2019 Jul 7;10(3):446-451. Epub 2019 Oct 7.

Department of Neurosurgery, University Hospital Dubrava, Zagreb, Croatia.

Neurotrauma is one of the leading causes of death and disabilities nowadays and represents one of the largest socioeconomic problems in rich countries, as well as developing ones. A satisfying, medically viable, and cost-effective model of managing acutely neurotraumatized patients, especially ones who come from distant and/or rural areas, has yet to be found. Patient outcome after acute neurotrauma depends on many factors of which the possibility of urgent treatment by an experienced specialist team has a crucial role. Here, we present our own way of managing acutely neurotraumatized patients from distant places which is unique in Croatia, the Dubrava model. We present our 5-year experience cooperating with general hospitals in four neighboring cities (Ĉakovec, Bjelovar, Sisak, and Koprivnica) in managing, operating, and taking care of acutely neurotraumatized patients. More than 300 surgeries have been performed in these hospitals through the Dubrava model. Our experience so far provides encouraging results that this system could also be successfully implemented in other institutions. Furthermore, we recorded an increased number of surgeries each year, as well as a good mutual cooperation with the local general hospitals. This trauma managing model is one of a kind in Croatia. We argue that it is not only better for the patients, providing them with better chances of survival, and disability-free recovery, but is also far superior in many ways to the dominant and currently prevalent way of treating these patients in other parts of Croatia. The Dubrava model of treating patients in rural and distant areas is a reliable and proven model with many benefits and as such its implementation should be considered in other institutions as well.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1055/s-0039-1697777DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6779563PMC
July 2019

Intracranial Mature Teratoma in an Adult Patient: A Case Report.

J Neurol Surg Rep 2019 Jan 3;80(1):e14-e17. Epub 2019 Apr 3.

Department of Neurosurgery, University Hospital Dubrava, Zagreb, Croatia.

: Primary intracranial teratoma is a subtype of germ cell tumors, classified into three subtypes. They occur very rarely, with only several reported individual cases in adults.  We present a patient with an intermittent headache in the right frontal region. Magnetic resonance imaging (MRI) revealed a right sided high frontal parasagittal mass that compressed the falx, the right lateral ventricle, as well as the brain parenchyma. Patient underwent surgical treatment. Histopathological analysis described mature teratoma. Four months after the surgical treatment there were no signs of residual intracranial mass or relapse.  Primary intracranial teratoma in adults has a nonspecific clinical presentation. MRI reveals a solitary irregular mass with multilocularity and mixed signals derived from different tissues. The patients age, biochemical markers, and patohistological analysis are necessary to confirm the diagnosis.  Teratoma treatment strategy still remains controversial. It includes radical resection whenever possible. Since the residual portion of mature teratoma may contain part of immature or malignant tissue, tumor recurrence after surgical removal is possible. Also, new tumor mass could occur at other sites intracranial after the initial one was removed. Thus, although patients usually recover, they should be followed-up for a long period of time.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1055/s-0039-1685213DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6447400PMC
January 2019

Primary dural lymphoma mimicking meningioma: a clinical and surgical case report.

J Surg Case Rep 2018 Aug 6;2018(8):rjy189. Epub 2018 Aug 6.

Department of Neurosurgery, University Hospital Dubrava, Zagreb, Croatia.

Introduction: Primary central nervous system lymphoma and its subtype, primary dural lymphoma, are types of non-Hodgkin's lymphoma that only occur in the central nervous system without any dissemination. They are extremely rare cases of extra nodal lymphomas accounting for 1--5% of intracranial tumors.

Case Report: We present a patient diagnosed with primary dural lymphoma in right frontal brain region who underwent surgical resection. Histopathological analysis revealed diffuse B-type large cell non-Hodgkin lymphoma. Patient underwent four cycles of R-CHOP and intrathecal methotrexate protocol. Six months postoperative, no signs of newly onset infiltration were present.

Discussion: Primary dural lymphoma most likely presents with unusual radiological signs, which can easily be mistaken for meningioma, the main differential diagnosis. A thorough immunological, histopathological and clinical patients profile should be conducted in order to establish the certainty of diagnosis. Although there are few treatment options: surgery, radiotherapy or chemotherapy, there is no established treatment protocol.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/jscr/rjy189DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6077807PMC
August 2018

Intraoperative identification of the corticospinal tract and dorsal column of the spinal cord by electrical stimulation.

J Neurol Neurosurg Psychiatry 2018 07 7;89(7):754-761. Epub 2018 Feb 7.

Department of Neurosurgery, Cantonal Hospital of Lucerne, University of Basel, Basel, Switzerland.

Objectives: Anatomical identification of the corticospinal tract (CT) and the dorsal column (DC) of the exposed spinal cord is difficult when anatomical landmarks are distorted by tumour growth. Neurophysiological identification is complicated by the fact that direct stimulation of the DC may result in muscle motor responses due to the centrally activated H-reflex. This study aims to provide a technique for intraoperative neurophysiological differentiation between CT and DC in the exposed spinal cord.

Methods: Recordings were obtained from 32 consecutive patients undergoing spinal cord tumour surgery from July 2015 to March 2017. A double train stimulation paradigm with an intertrain interval of 60 ms was devised with recording of responses from limb muscles.

Results: In non-spastic patients (55% of cohort) an identical second response was noted following the first CT response, but the second response was absent after DC stimulation. In patients with pre-existing spasticity (45%), CT stimulation again resulted in two identical responses, whereas DC stimulation generated a second response that differed substantially from the first one. The recovery times of interneurons in the spinal cord grey matter were much shorter for the CT than those for the DC. Therefore, when a second stimulus train was applied 60 ms after the first, the CT-fibre interneurons had already recovered ready to generate a second response, whereas the DC interneurons were still in the refractory period.

Conclusions: Mapping of the spinal cord using double train stimulation allows neurophysiological distinction of CT from DC pathways during spinal cord surgery in patients with and without pre-existing spasticity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/jnnp-2017-317172DOI Listing
July 2018

Brain biopsy performed with the RONNA G3 system: a case study on using a novel robotic navigation device for stereotactic neurosurgery.

Int J Med Robot 2018 Feb 12;14(1). Epub 2017 Dec 12.

Department of Neurosurgery, University Hospital Dubrava, Zagreb, Croatia.

Background: Robotic neuronavigation is becoming an important tool for neurosurgeons. We present a case study of a frameless stereotactic biopsy guided by the RONNA G3 robotic neuronavigation system.

Methods: A 45 year-old patient with a history of vertigo, nausea and vomiting was diagnosed with multiple periventricular lesions. Neurological status was unremarkable. A frameless robotic biopsy of a brain lesion was performed.

Results: Three tissue samples were obtained. There were no intraoperative or postoperative complications. Histological analysis showed a B-cell lymphoma. After merging the preoperative CT scan with the postoperative MRI and CT scans, the measured error between the planned and the postoperatively measured entry point was 2.24 mm and the measured error between the planned and postoperatively measured target point was 2.33 mm.

Conclusions: The RONNA G3 robotic system was used to navigate a Sedan brain biopsy needle to take tissue samples and could be a safe and precise tool for brain biopsy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/rcs.1884DOI Listing
February 2018

Deep brain stimulation for the early treatment of the minimally conscious state and vegetative state: experience in 14 patients.

J Neurosurg 2018 04 16;128(4):1189-1198. Epub 2017 Jun 16.

6Center for Physical Medicine and Rehabilitation, University Hospital Dubrava, Zagreb.

OBJECTIVE An effective treatment of patients in a minimally conscious state (MCS) or vegetative state (VS) caused by hypoxic encephalopathy or traumatic brain injury (TBI) is not yet available. Deep brain stimulation (DBS) of the thalamic reticular nuclei has been attempted as a therapeutic procedure mainly in patients with TBI. The purpose of this study was to investigate the therapeutic use of DBS for patients in VS or MCS. METHODS Fourteen of 49 patients in VS or MCS qualified for inclusion in this study and underwent DBS. Of these 14 patients, 4 were in MCS and 10 were in VS. The etiology of VS or MCS was TBI in 4 cases and hypoxic encephalopathy due to cardiac arrest in 10. The selection criteria for DBS, evaluating the status of the cerebral cortex and thalamocortical reticular formation, included: neurological evaluation, electrophysiological evaluation, and the results of positron emission tomography (PET) and MRI examinations. The target for DBS was the centromedian-parafascicular (CM-pf) complex. The duration of follow-up ranged from 38 to 60 months. RESULTS Two MCS patients regained consciousness and regained their ability to walk, speak fluently, and live independently. One MCS patient reached the level of consciousness, but was still in a wheelchair at the time the article was written. One VS patient (who had suffered a cerebral ischemic lesion) improved to the level of consciousness and currently responds to simple commands. Three VS patients died of respiratory infection, sepsis, or cerebrovascular insult (1 of each). The other 7 patients remained without substantial improvement of consciousness. CONCLUSIONS Spontaneous recovery from MCS/VS to the level of consciousness with no or minimal need for assistance in everyday life is very rare. Therefore, if a patient in VS or MCS fulfills the selection criteria (presence of somatosensory evoked potentials from upper extremities, motor and brainstem auditory evoked potentials, with cerebral glucose metabolism affected not more than the level of hypometabolism, which is judged using PET), DBS could be a treatment option.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3171/2016.10.JNS161071DOI Listing
April 2018

Excellent outcome of pallidal deep brain stimulation in DYT6 dystonia: A case report.

J Neurol Sci 2016 Jul 19;366:18-19. Epub 2016 Apr 19.

Geriatric Department, Memory Clinic Bldg 20, University Hospital Oslo, Oslo University, Oslo, Norway.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jns.2016.04.032DOI Listing
July 2016

Monoamine Neurotransmitter Metabolite Concentration as a Marker of Cerebrospinal Fluid Volume Changes.

Acta Neurochir Suppl 2016 ;122:283-6

Department of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia.

Objective: In our previous papers we demonstrated that changes in blood and cerebrospinal fluid (CSF) osmolarity have a strong influence on CSF pressure and volume, which is in accordance with a new proposed hypothesis of CSF physiology. Thus, acute changes in CSF volume should be reflected in the CSF concentration of different central nervous system (CNS) metabolites.

Methods: In anesthetized cats (n = 4) we measured the outflow volume of CSF by cisternal free drainage at a negative CSF pressure (-10 cmH2O) before and after the intraperitoneal (i.p.) application of a hypo-osmolar substance (distilled water). In samples of CSF collected at different time intervals (30 min) we measured the concentration of homovanillic acid (HVA).

Results: In spite of fact that constant CSF outflow volume was obtained after a 30-min period in our model, the concentration of HVA gradually increased over time and became stable after 90 min. After the i.p. application of distilled water the outflow CSF volume increased significantly, whereas the concentration of HVA significantly decreased over 30 min.

Conclusions: The results observed suggest that alterations in serum osmolarity change the CSF volume and concentrations of neurotransmitter metabolites because of the osmotic arrival of water from CNS blood capillaries in all CSF compartments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/978-3-319-22533-3_56DOI Listing
July 2017

Tongue somatosensory-evoked potentials in microvascular decompression treated trigeminal neuralgia.

Acta Neurol Belg 2014 Mar 26;114(1):55-8. Epub 2013 Nov 26.

Department of Neurology, Referral Center for Demyelinating Diseases of the Central Nervous System, Zagreb School of Medicine and University Hospital Center, Kišpatićeva 12, 10000, Zagreb, Croatia.

Somatosensory-evoked potentials of the tongue (tSSEP) provide useful information about trigeminal-afferent pathway. The aim of this study was to evaluate tSSEP in trigeminal neuralgia (TN) treatment with microvascular decompression. Two patients with trigeminal neuralgia refractory to conservative treatment underwent microvascular decompression of the trigeminal nerve. tSSEP was performed a month prior to surgery and in the month after the surgery in both patients. Pain frequency and tSSEP were analyzed before and after surgery. In both patients, a complete resolution of pain occurred. In patient 1, tSSEP latencies became shorter than before surgery and wave N1 appeared. The intensity of stimulation necessary to reach the threshold was 4 mA before the surgery and 1 mA after the surgery. A complete recovery of tSSEP after the operation was achieved in patient 2. The results of present study demonstrate potential value of tSSEP in pre-surgery evaluation and post-surgery follow-up of TN patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s13760-013-0260-0DOI Listing
March 2014

Difficulties with diagnosis and consequential poor outcome due to stigma of acquired immunodeficiency syndrome - a case report.

Pathog Glob Health 2013 Sep 1;107(6):325-8. Epub 2013 Aug 1.

University Hospital Dubrava, Zagreb, Croatia.

Low incidence of human immunodeficiency virus (HIV) infections and acquired immunodeficiency syndrome (AIDS) has been detected in Croatia so far. Toxoplasmic encephalitis (TE) is the most common opportunistic cerebral infection in AIDS patients and is highly responsive to antiparasitic chemotherapy, if treated at an early stage. We present the case of the brain biopsy confirmed as TE on a 36-year-old female patient who at admission presented with unconsciousness and a right hemiplegia. A MSCT was performed and two hypodense lesions were diagnosed. The patient's family initially denied the presence or history of any medical problem or infection. An MRI showed multiple ring-enhanced mass lesions. An infectologist required a brain biopsy to exclude cerebral lymphoma and multiple metastases. Pathohistological analysis suggested TE. Meanwhile, patient's blood samples were found to be HIV positive. The patient was transferred to University Hospital for Infectious Diseases in Zagreb, where she died 2 days following admission. The patient's family terminally confessed that the patient had been HIV positive for 10 years and had refused any treatment. Family's denial of infection as well as 'hiding information' concerning patient's health from physicians involved in her treatment caused a delay in proper on-time patient treatment. We would like to emphasize that TE must be considered as a differential diagnosis in patients presenting with multiple cerebral lesions, including patients without acknowledged past history of HIV infection. A stigma towards HIV infection and ignorance of the disease still exist and therefore hinders proper treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1179/2047773213Y.0000000108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4001613PMC
September 2013

Implantation metastasis of malignant fibrous histiocytoma along the stereotactic biopsy tract.

Clin Neurol Neurosurg 2013 Jul 3;115(7):1160-1. Epub 2012 Oct 3.

Department of Neurosurgery, Clinical Hospital Dubrava, Zagreb, Croatia.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clineuro.2012.09.018DOI Listing
July 2013

Dependence of cerebrospinal fluid pressure and volume on the changes in serum osmolarity in cats.

Acta Neurochir Suppl 2012 ;114:351-5

Department of Pharmacology, University of Zagreb School of Medicine, Zagreb, Croatia.

Objectives: To study the effect of blood osmolarity on cerebrospinal fluid (CSF) volume and CSF pressure in cats.

Methods: Three types of methods were used on anesthetized cats. The first, ventriculo-cisternal perfusion (12.96 μL/min) before and after i.v. application of 20% mannitol; the second, measuring the outflow of CSF by cisternal free drainage; and the third, measuring CSF pressure in the ventricles of an intact CSF system, with the second and third method being performed before and after the i.p. application of a hypo-osmolar substance (distilled water).

Results: In the first group, the application of 20% mannitol led to a significantly reduced (p < 0.005) outflow volume (from 12.60 ± 0.29 to 0.94 ± 0.09 μL/min). In the second group, the outflow CSF volume significantly increased (p < 0.001) after the application of distilled water (from 18.8 ± 0.3 to 28.2 ± 0.7 μL/min). In the third group, after the application of distilled water, the CSF pressure also significantly increased (p < 0.05; from 8.3 ± 0.8 to 16.1 ± 0.14 cm H(2)O).

Conclusion: We conclude that changes in serum osmolarity change the CSF volume because of the osmotic gradient between the blood and all of the CSF compartments, and also that the change in CSF pressure is closely associated with changes in CSF volume.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/978-3-7091-0956-4_68DOI Listing
May 2012

Potential error in ventriculocisternal perfusion method for determination of cerebrospinal fluid formation rate in cats.

Coll Antropol 2011 Jan;35 Suppl 1:73-7

University of Zagreb, Dubrava University Hospital, Department of Neurosurgery, Zagreb, Croatia.

The cerebrospinal fluid (CSF) formation rate (Vf) has been extensively studied by the ventriculocisternal perfusion, a method still regarded as the most precise one. This method as well as the equation for the calculation of the CSF formation rate (Vf) was established by Heisey et al on indicator dilution in perfusate. They assumed that the dilution of the indicator substance in perfusion is a consequence of newly formed CSF i.e. a higher CSF formation rate would result in a higher degree of dilution of the indicator substance. Therefore, such method is indirect and any mistake in the interpretation of the degree of indicator dilution would lead to questionable and often contradictory results regarding CSF formation rates. According to Heisey's equation, Vf shoud not depend on the rate of ventriculocisternal perfusion. However it has been shown that Vf is perfusion dependt value, and also that during perfusion the indicator substance is partially absorbed into surrounding tissue. It is possible that obtained Vf dependence on perfusion rate was caused by observed absorption of indicator substances. For that reason, in anaesthetised cats ventriculocisternal perfusion was performed at higher (252.0 microL/min) and at lower perfusion rate (65.5 microL/min) and Vf was calculated at both experimental and corrected (just for absorbed amount) values of indicator substance. Since (inspite of the correction) the difference of 12.4 microL/min between lower (15.0 microL/min) and higher perfusion rate (27.4 microL/min) was obtained, it is obvious that ventriculocisternal perfusion method cannot be considered reliable for measuring CSF formation rate.
View Article and Find Full Text PDF

Download full-text PDF

Source
January 2011

Extracranial propagation of glioblastoma with extension to pterygomaxillar fossa.

World J Surg Oncol 2011 May 19;9:53. Epub 2011 May 19.

Department of Neurosurgery, Clinical Hospital Dubrava, Zagreb, Croatia.

Background: Glioblastoma multiforme is a highly malignant primary brain tumor that shows marked local aggressiveness, but extracranial spread is not a common occurrence. We present an unusual case of recurrent glioblastoma in 54-year old male that spread through the scull base to the ethmoid and sphenoid sinuses, to the orbita, pterygomaxillar fossa, and to the neck.

Methods: A 54-year old male underwent left temporal resection because of brain tumor of his left temporal lobe. Operation was followed by external beam radiation combined with temozolomide. The tumor recurred eight months after first surgery. The patient developed swelling of left temporal region, difficult swallowing and headache. MRI of head showed recurrent tumor, which invaded orbita, ethmoid and sphenoid sinuses, nasal cavity, pterygomaxillar fossa.

Results: The patient died ten months after initial diagnosis of glioblastoma multiforme, and two months after his second operation.

Conclusions: The aggressive surgical operation helped to downsize the tumor mass as much as possible, but did not prolonged significantly the life or improved the life quality of the patient. The current literature is reviewed, and the diagnostic approaches as well as therapeutic options are discussed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/1477-7819-9-53DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3117736PMC
May 2011

Nightmare complication after lumbar disc surgery: cranial nontraumatic acute epidural hematoma.

Spine (Phila Pa 1976) 2011 Dec;36(26):E1761-4

Department of Neurosurgery, University Hospital Dubrava, Zagreb, Croatia.

Study Design: Case report.

Objective: The nontraumatic cranial epidural hematoma is an extremely rare clinical entity and it commonly occurs in the presence of infectious diseases as complication of sinusitis, coagulopathy, vascular malformation of the dura, hemorrhagic tumor, in patients with sickle cell disease, systemic lupus erythematosus, after open heart surgery, and in patients on hemodialysis.

Summary Of Background Data: We reported a case of spontaneous epidural hematoma that occurred after herniated disc surgery. There was no history of preceding head trauma and patient medical history was unremarkable. To date, no report is found of cranial epidural hematoma after lumbar discectomy.

Methods: A 58-year-old woman was operated because of a herniated disc at lumbar L3-L4 level and spinal stenosis. Bilateral L3-L4 interlaminectomies and L3-L4 discectomy were performed. Hemovac drain was placed in epidural space. Four hours after surgery, the patient developed left side weakness accompanied with nausea, vomiting, and severe headache. Urgent computed tomography of the head showed acute cranial epidural hematoma and the patient underwent emergent surgery. There was no evidence of trauma of the scalp or any other anatomical abnormality. Control computed tomography 14 hours after evacuation of the hematoma showed new extradural hematoma at the site of the previous one. Patient underwent second surgery.

Results: Nine days after operation of the spine, patient recovered completely with no neurological deficit, but the cerebrospinal fluid showed at the place of spinal wound. Patient was operated once more and a minor dural tear was revealed, which was repaired. The patient was discharged on ninth postoperative and she recovered completely.

Conclusion: There have been described rare cases of spontaneous subdural, intracerebral, and intracerebellar hematoma caused by intracranial hypotension, but this is the first described case of spontaneous cranial epidural hematoma after lumbar disc surgery caused by intracranial hypotension.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/BRS.0b013e31821cb9fdDOI Listing
December 2011

Effect of osmolarity on CSF volume during ventriculo-aqueductal and ventriculo-cisternal perfusions in cats.

Neurosci Lett 2010 Oct 30;484(2):93-7. Epub 2010 Jul 30.

Department of Neurosurgery, Dubrava University Hospital, Avenija G. Suska 6, 10000 Zagreb, Croatia.

The effect of cerebrospinal fluid (CSF) osmolarity on the CSF volume has been studied on different CSF/brain tissue contact areas. It has been shown, on anesthetized cats under normal CSF pressure, that the perfusion of CSF system (12.96 μl/min) by hyperosmolar CSF (400 mOsml/l) leads to significantly higher outflow volume (μl/min) during ventriculo-cisternal perfusion (29.36 ± 1.17 and 33.50 ± 2.78) than the ventriculo-aqueductal perfusion (19.58 ± 1.57 and 22.10 ± 2.31) in experimental period of 30 or 60 min. Both of these hyperosmolar perfusions resulted in significantly higher outflow volume than the perfusions by isoosmolar artificial CSF (12.86 ± 0.96 and 13.58 ± 1.64). These results suggest that the volume of the CSF depends on both the CSF osmolarity and the size of the contact area between CSF system and surrounding tissue exposed to hyperosmolar CSF. However, all of these facts imply that the control of the CSF volume is not in accordance with the classical hypothesis of cerebrospinal fluid hydrodynamic. According to this hypothesis, the CSF volume should be regulated by active formation of CSF (secretion) inside the brain ventricles and passive CSF absorption outside of the brain. Obtained results correspond to the new hypothesis which claims that the volume of CSF depends on the gradients of hydrostatic and osmotic forces between the blood on one side and extracellular fluid and CSF on the other. The CSF exchange between the entire CSF system and the surrounding tissue should, therefore, be determined by (patho)physiological conditions that predominate within those compartments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neulet.2010.07.058DOI Listing
October 2010

Frontal variant of Alzheimer's disease: clinico-CSF-pathological correlation.

Can J Neurol Sci 2010 Jan;37(1):118-20

Department of Neurology, Zagreb School of Medicine and University Hospital Center, Zagreb, Croatia.

View Article and Find Full Text PDF

Download full-text PDF

Source
January 2010