RBRoman Bošnjak

Roman Bošnjak

*This is an algorithmically generated author record based on publicly available information.

Current Organizations / Institutes

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Roman Bošnjak has a total of 119 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    A Successful Control of the Intraoperative Bleeding from McConnell’s Artery during Fully Endoscopic Resection of Planum Sphenoidale Meningioma Using Bone Chip and Bioglue : A Case Report

    by Guenther C Feigl, Roman Bosnjak, Daniel Staribacher, Gavin Britz, Dzmitry Kuzmin

    The endoscopic transsphenoidal approach is a common approach used in skull base neurosurgery to reach the sellar region. One of the intraoperative risks of this approach is intraoperative bleeding out of the carotid artery. Gentle drilling can prevent carotid artery injury. However, injury to smaller branches, such as the McConnell’s capsular artery, which is located within the surgical corridor, is more difficult to prevent. If such an injury is within the junction to the main trunk of the carotid artery, there will be a small circular defect in this area. This can result in massive blood loss and should be closed surgically immediately. We describe a clinical case of intraoperative bleeding from the McConnell’s artery originating from the carotid arterial segment (C4) in a 78-year-old female patient operated on for planum sphenoidale meningioma via endoscopic transsphenoidal approach, as well as provide a technical note on a possible technique for bleeding control in such cases. Pinpoint carotid bleeding as a result of intraoperative injury can be stopped by wedging a bone fragment in the carotid canal and fixing it in that position with histoacryl glue at the defect site.


  • Open Access

    Transglabellar Butterfly Incision for Anterior Cranial Vault Access: Case Report

    by Jure Urbančič, Roman Bošnjak, Domen Vozel

    (1) Background: The transglabellar approach, a type of transfacial technique, typically involves glabellar resection and opening the frontal sinus via a bicoronal incision, providing access to the anterior cranial vault. To prevent complications, the frontal sinus is typically obliterated. However, the success of transnasal endoscopic techniques has prompted a re-evaluation of these traditional methods. (2) Methods: This paper provides a brief literature review and discusses the removal of an elongated glioma of the left gyrus rectus (4.4 × 1.9 × 2.2 cm) in a 63-year-old male using a transglabellar subfrontal approach via a butterfly incision, with frontal sinus preservation. (3) Results: An uneventful gross-total resection of a WHO grade II oligodendroglioma was achieved. There is a paucity of literature describing a transglabellar subfrontal approach via a butterfly incision with frontal sinus preservation. (4) Conclusions: The described approach could be utilized in selected cases such as small intra-axial lesions oriented longitudinally along the inferomedial frontal lobe from the posterior wall of the frontal sinus to the anterior communicating artery complex in patients with pre-existing glabellar rhytids. Since this is merely a case presentation, we cannot conclude that this represents established clinical practice. The outcomes of this approach should be investigated in the future.


  • Open Access

    A Multidisciplinary Skull Base Board for Tumour and Non-Tumour Diseases: Initial Experiences

    by Jure Urbančič, Saba Battelino, Roman Bošnjak, Tomislav Felbabić, Nejc Steiner, Matej Vouk, Matej Vrabec, Domen Vozel

    The skull base is the area where various cancerous and non-cancerous diseases occur and represents the intersection of several medical fields. The key is an integrated treatment by specialists of multiple disciplines. We prospectively analysed patients with a skull base disease between August 2022 and 2023 and presented to the Multidisciplinary Skull Base Board (MDT-SB), which takes place once a month hybridly (in-person and remotely). Thirty-nine patients (median age of 58.2 years) were included, of which twelve (30.8%) had a benign tumour, twelve (30.8%) had a malignant tumour, five had an infection (12.8%), and ten (25.6%) had other diseases. For each patient, at least two otorhinolaryngologists, a neurosurgeon, and a neuroradiologist, as well as an infectious disease specialist, a paediatrician, an oculoplastic surgeon, a maxillofacial surgeon, and a pathologist were involved in 10%, 8%, 8%, 3%, and 3% of cases, respectively. In fifteen patients (38%), the MDT-SB suggested surgical treatment; in fourteen (36%), radiological follow-ups; in five (13%), non-surgical treatments; in two, conservative treatments (5%); in two (5%), surgical and conservative treatments; and in one (3%), a biopsy. Non-cancerous and cancerous diseases of the skull base in adults and children should be presented to the MDT-SB, which consists of at least an otolaryngologist, a neurosurgeon, and a neuroradiologist.


  • Open Access

    COVID-19 and Surgical Practice in Slovenia: Managing the Crisis in Neurosurgery during the COVID-19 Pandemic

    by Matic Munda, Tomaz Velnar, Roman Bosnjak, Tilen Zele, Lidija Gradisnik, Peter Spazzapan, Natasa Kos, Nina Kocivnik, Mitja Benedicic, Borut Prestor

    Worldwide, the novel coronavirus disease 2019 (COVID-19) has become a significant threat to global health. Worldwide, COVID-19 has affected the health service also in Slovenia. During this time, neurosurgery is facing difficulties in its service, both in emergency and elective surgeries. In the article, we describe the anti-COVID-19 measures taken at our neurosurgical department in a medical centre in Ljubljana, Slovenia, and analysed and compared the number of emergency and elective neurosurgical procedures during the time of the pandemic.


  • Open Access

    Atypical Skull-Base Osteomyelitis: Comprehensive Review and Multidisciplinary Management Viewpoints

    by Jure Urbančič, Domen Vozel, Saba Battelino, Roman Bošnjak, Barbara Kokošar Ulčar, Tadeja Matos, Matic Munda, Lea Papst, Nejc Steiner, Matej Vouk, et al.

    Atypical skull-base osteomyelitis is a rare but fatal disease that usually involves infection of the ethmoid, sphenoid, occipital, or temporal bones that form the skull base. Unlike typical (so-called otogenic), atypical skull-base osteomyelitis has no otogenic cause. Instead, some authors call atypical skull-base osteomyelitis sinonasal, since the infection most often originates from the nose and paranasal sinuses. Diagnosing and treating this disease is challenging. To assist in managing atypical skull-base osteomyelitis, a review of the most recent literature, with patient cases and multidisciplinary perspectives from otolaryngologists, neurosurgeons, radiologists, infectious disease specialists, pathologists, and clinical microbiologists, is provided in this paper.


  • Open Access

    Spinal Stenosis with Sacral Osseous Deformity Mimicking Chronic Inflammatory Demyelinating Polyneuropathy

    by Vlado Stolevski, Roman Bosnjak, Boro Ilievski, Aleksandar Dimovski

    BACKGROUND: Differential diagnoses of neurosurgical spinal disorders and polyneuropathies have been recognized to cause clinical perplexity, occasionally misdiagnosing chronic inflammatory demyelinating polyneuropathy (CIDP). When nerve conduction studies and cerebrospinal fluid (CSF) analyses reinforce a certain clinical presentation, the importance of imaging studies, conservative treatment response, and interdisciplinary clinical approach should be highly emphasized. CASE PRESENTATION: We report a 51-year-old patient who presented with a 16-week history of neurogenic claudication and right-sided lower extremity monoparesis, with low back pain syndrome dating from 10 years ago. He was initially evaluated by a neurologist under the suspicion of CIDP, supported by nerve conduction studies and CSF analyses, without any subjective or objective improvements after systemic corticosteroid therapy. After performing magnetic resonance imaging (MRI) of the lumbosacral spine, he was referred to a neurosurgeon. Neurological examination revealed features of lower motor neuron lesion, consistent with the MRI findings of L4-L5 and L5-S1 stenosis with right-sided S1 vertebra osseous deformity, without any radiographic evidence of CIDP. The patient underwent surgery and improvements were noted early in the post-operative recovery phase and continuously throughout the regular monthly follow-ups, without any clinical features of CIDP. Histopathology results confirm sacral osseous deformity. No evidence of CIDP, osseous deformity residue, or recurrence was evident on the post-operative MRI control performed 11-month post-surgery. CONCLUSIONS: Degenerative spinal stenosis compromising spinal canal dimensions can mimic CIDP due to sharing multiple clinical similarities. That scenario is especially highlighted when age-related spinal degenerative disease is unexpected and seldom aggravated by spinal osseous lesions. Avoiding misdiagnosis and providing adequate treatment can pose a serious challenge for neurosurgeons and neurologists, demonstrating the importance of an interdisciplinary approach toward diverse spinal disorders.

  • Open Access

    The Cytotoxic Effects of Cannabidiol and Cannabigerol on Glioblastoma Stem Cells May Mostly Involve GPR55 and TRPV1 Signalling

    by Tamara T. Lah, Bernarda Majc, Metka Novak, Ajda Sušnik, Barbara Breznik, Andrej Porčnik, Roman Bošnjak, Aleksander Sadikov, Marta Malavolta, Selma Halilčević, et al.

    Glioblastoma (GBM) is one of the most aggressive cancers, comprising 60–70% of all gliomas. The large G-protein-coupled receptor family includes cannabinoid receptors CB1, CB2, GPR55, and non-specific ion receptor protein transporters TRPs. First, we found up-regulated CNR1, GPR55, and TRPV1 expression in glioma patient-derived tissue samples and cell lines compared with non-malignant brain samples. CNR1 and GPR55 did not correlate with glioma grade, whereas TRPV1 negatively correlated with grade and positively correlated with longer overall survival. This suggests a tumour-suppressor role of TRPV1. With respect to markers of GBM stem cells, preferred targets of therapy, TRPV1 and GPR55, but not CNR1, strongly correlated with different sets of stemness gene markers: NOTCH, OLIG2, CD9, TRIM28, and TUFM and CD15, SOX2, OCT4, and ID1, respectively. This is in line with the higher expression of TRPV1 and GPR55 genes in GSCs compared with differentiated GBM cells. Second, in a panel of patient-derived GSCs, we found that CBG and CBD exhibited the highest cytotoxicity at a molar ratio of 3:1. We suggest that this mixture should be tested in experimental animals and clinical studies, in which currently used Δ9-tetrahydrocannabinol (THC) is replaced with efficient and non-psychoactive CBG in adjuvant standard-of-care therapy.


  • Open Access

    Clinical Applications of Poly-Methyl-Methacrylate in Neurosurgery: The In Vivo Cranial Bone Reconstruction

    by Tomaz Velnar, Roman Bosnjak, Lidija Gradisnik

    Background: Biomaterials and biotechnology are becoming increasingly important fields in modern medicine. For cranial bone defects of various aetiologies, artificial materials, such as poly-methyl-methacrylate, are often used. We report our clinical experience with poly-methyl-methacrylate for a novel in vivo bone defect closure and artificial bone flap development in various neurosurgical operations. Methods: The experimental study included 12 patients at a single centre in 2018. They presented with cranial bone defects after various neurosurgical procedures, including tumour, traumatic brain injury and vascular pathologies. The patients underwent an in vivo bone reconstruction from poly-methyl-methacrylate, which was performed immediately after the tumour removal in the tumour group, whereas the trauma and vascular patients required a second surgery for cranial bone reconstruction due to the bone decompression. The artificial bone flap was modelled in vivo just before the skin closure. Clinical and surgical data were reviewed. Results: All patients had significant bony destruction or unusable bone flap. The tumour group included five patients with meningiomas destruction and the trauma group comprised four patients, all with severe traumatic brain injury. In the vascular group, there were three patients. The average modelling time for the artificial flap modelling was approximately 10 min. The convenient location of the bone defect enabled a relatively straightforward and fast reconstruction procedure. No deformations of flaps or other complications were encountered, except in one patient, who suffered a postoperative infection. Conclusions: Poly-methyl-methacrylate can be used as a suitable material to deliver good cranioplasty cosmesis. It offers an optimal dural covering and brain protection and allows fast intraoperative reconstruction with excellent cosmetic effect during the one-stage procedure. The observations of our study support the use of poly-methyl-methacrylate for the ad hoc reconstruction of cranial bone defects.


  • Open Access

    The Endplate Role in Degenerative Disc Disease Research: The Isolation of Human Chondrocytes from Vertebral Endplate—An Optimised Protocol

    by Lidija Gradišnik, Uroš Maver, Boris Gole, Gorazd Bunc, Matjaž Voršič, Janez Ravnik, Tomaž Šmigoc, Roman Bošnjak, Tomaž Velnar

    Background: Degenerative disc disease is a progressive and chronic disorder with many open questions regarding its pathomorphological mechanisms. In related studies, in vitro organ culture systems are becoming increasingly essential as a replacement option for laboratory animals. Live disc cells are highly appealing to study the possible mechanisms of intervertebral disc (IVD) degeneration. To study the degenerative processes of the endplate chondrocytes in vitro, we established a relatively quick and easy protocol for isolating human chondrocytes from the vertebral endplates. Methods: The fragments of human lumbar endplates following lumbar fusion were collected, cut, ground and partially digested with collagenase I in Advanced DMEM/F12 with 5% foetal bovine serum. The sediment was harvested, and cells were seeded in suspension, supplemented with special media containing high nutrient levels. Morphology was determined with phalloidin staining and the characterisation for collagen I, collagen II and aggrecan with immunostaining. Results: The isolated cells retained viability in appropriate laboratory conditions and proliferated quickly. The confluent culture was obtained after 14 days. Six to 8 h after seeding, attachments were observed, and proliferation of the isolated cells followed after 12 h. The cartilaginous endplate chondrocytes were stable with a viability of up to 95%. Pheno- and geno-typic analysis showed chondrocyte-specific expression, which decreased with passages. Conclusions: The reported cell isolation process is simple, economical and quick, allowing establishment of a viable long-term cell culture. The availability of a vertebral endplate cell model will permit the study of cell properties, biochemical aspects, the potential of therapeutic candidates for the treatment of disc degeneration, and toxicology studies in a well-controlled environment.


  • Open Access

    Neurosurgical Approaches to Brain Tissue Harvesting for the Establishment of Cell Cultures in Neural Experimental Cell Models

    by Lidija Gradišnik, Roman Bošnjak, Gorazd Bunc, Janez Ravnik, Tina Maver, Tomaž Velnar

    In recent decades, cell biology has made rapid progress. Cell isolation and cultivation techniques, supported by modern laboratory procedures and experimental capabilities, provide a wide range of opportunities for in vitro research to study physiological and pathophysiological processes in health and disease. They can also be used very efficiently for the analysis of biomaterials. Before a new biomaterial is ready for implantation into tissues and widespread use in clinical practice, it must be extensively tested. Experimental cell models, which are a suitable testing ground and the first line of empirical exploration of new biomaterials, must contain suitable cells that form the basis of biomaterial testing. To isolate a stable and suitable cell culture, many steps are required. The first and one of the most important steps is the collection of donor tissue, usually during a surgical procedure. Thus, the collection is the foundation for the success of cell isolation. This article explains the sources and neurosurgical procedures for obtaining brain tissue samples for cell isolation techniques, which are essential for biomaterial testing procedures.