Rok Hren

Dr. Rok Hren

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
20 August 2022 in Sensors
Verified
Journal Article
Open access
PDF file
JSJošt Stergar
Jošt Stergar
RHRok Hren
Rok Hren
Matija MilanicMatija Milanic
Matija Milanic
Hyperspectral imaging (HSI) is a promising optical modality that is already being used in numerous applications. Further expansion of the capabilities of HSI depends on the modularity and versatility of the systems, which would, inter alia, incorporate profilometry, fluorescence imaging, and Raman spectroscopy while following a rigorous calibration and verification protocols, thus offering new insights into the studied samples as well as verifiable, quantitative measurement results applicable to the development of quantitative metrics. Considering these objectives, we developed a custom-made laboratory HSI system geared toward biomedical applications. In this report, we describe the design, along with calibration, characterization, and verification protocols needed to establish such systems, with the overall goal of standardization. As an additional novelty, our HSI system uses a custom-built broadband LED-based light source for reflectance imaging, which is particularly important for biomedical applications due to the elimination of sample heating. Three examples illustrating the utility and advantages of the integrated system in biomedical applications are shown. Our attempt presents both the development of a custom-based laboratory HSI system with novel LED light source as well as a framework which may improve technological standards in HSI system design.

25 April 2024 in Healthcare
Verified
Journal Article
Open access
PDF file
ILIga Lipska
Iga Lipska
RBRossella Di Bidino
Rossella Di Bidino
MNMaciej Niewada
Maciej Niewada
BNBertalan Nemeth
Bertalan Nemeth
TBTomasz Bochenek
Tomasz Bochenek
RHRok Hren
Rok Hren
The purpose of this article is to investigate the common facilitators and barriers associated with the implementation of hospital-based health technology assessment (HB-HTA) across diverse hospital settings in seven countries. Through a two-round Delphi study, insights were gathered from a panel of 15 HTA specialists from France, Hungary, Italy, Kazakhstan, Poland, Switzerland, and Ukraine. Experts initially conducted a comprehensive review of the HB-HTA implementation in their respective countries, identifying the barriers and facilitators through descriptive analysis. Subsequently, panel experts ranked these identified barriers and facilitators on a seven-point Likert scale. A median agreement score ≥ 6 and interquartile range (IQR) ≤ 1 was accepted as reaching a consensus. Out of the 12 statements categorized as external and internal barriers and facilitators, the expert panel reached consensus on six statements (two barriers and four facilitators). The external barrier, which achieved consensus, was the lack of the formal recognition of the role of HB-HTA in national or regional legislations. The internal barrier reaching consensus was the limited availability of human resources dedicated to HB-HTA. This qualitative study indicates that HB-HTA still has progress to make before being formally accepted and integrated across most countries, although by building on the facilitating factors we identified there may be an opportunity for the implementation of internationally developed strategies to strengthen HB-HTA practices.

21 February 2023 in Sensors
Verified
Journal Article
Open access
PDF file
JSJošt Stergar
Jošt Stergar
RHRok Hren
Rok Hren
Matija MilanicMatija Milanic
Matija Milanic
Hyperspectral microscope imaging (HMI) is an emerging modality that integrates spatial information collected by standard laboratory microscopy and the spectral-based contrast obtained by hyperspectral imaging and may be instrumental in establishing novel quantitative diagnostic methodologies, particularly in histopathology. Further expansion of HMI capabilities hinges upon the modularity and versatility of systems and their proper standardization. In this report, we describe the design, calibration, characterization, and validation of the custom-made laboratory HMI system based on a Zeiss Axiotron fully motorized microscope and a custom-developed Czerny-Turner-type monochromator. For these important steps, we rely on a previously designed calibration protocol. Validation of the system demonstrates a performance comparable to classic spectrometry laboratory systems. We further demonstrate validation against a laboratory hyperspectral imaging system for macroscopic samples, enabling future comparison of spectral imaging results across length scales. An example of the utility of our custom-made HMI system on a standard hematoxylin and eosin-stained histology slide is also shown.

Verified
Journal Article
Open access
PDF file
TKTomasz Kluszczynski
Tomasz Kluszczynski
BNBertalan Nemeth
Bertalan Nemeth
MWMagdalena Wladysiuk
Magdalena Wladysiuk
MCMarcin Czech
Marcin Czech
MKMaria Kamusheva
Maria Kamusheva
RHRok Hren
Rok Hren
This study examines patient access to orphan medicinal products (OMPs) in Central and Eastern Europe (CEE) over the past five years, focusing on seven countries: Bulgaria, Czechia, Hungary, Poland, Romania, Slovakia, and Slovenia. While these jurisdictions have undergone rapid healthcare transformations, significant disparities in OMP access persist compared to Western Europe. This study aimed to address this gap by identifying barriers and enablers to optimize patient access to OMPs in a sustainable and equitable manner. A mixed-methodology approach was utilized, combining systematic literature reviews, in-depth interviews, and advisory board insights. Perspectives were gathered from a wide range of stakeholders, including policymakers, payers, academia, industry associations, and patient advocacy groups. Additionally, the study incorporated data from CEE-specific initiatives to triangulate findings and evaluate barriers, enablers, and best practices in OMP access. The analysis identified sub-optimal OMP access across most CEE countries, marked by prolonged delays and lower reimbursement rates compared to Western Europe, with Slovenia and Czechia as notable exceptions. Key barriers include limited awareness, inadequate health technology assessment (HTA) frameworks, insufficient financing mechanisms, underutilization of novel access schemes, and fragmented patient engagement. Conversely, enablers include the presence of rare disease policies, OMP-specific HTA frameworks, and patient-inclusive decision-making processes.

1 September 2024 in Radiology and Oncology
Verified
Journal Article
Open access
PDF file
RHRok Hren
Rok Hren
SBSimona Kranjc Brezar
Simona Kranjc Brezar
UMUrban Marhl
Urban Marhl
GSGregor Sersa
Gregor Sersa
Background: Laser speckle coherence imaging (LSCI) is an emerging imaging modality that enables noninvasive visualization and assessment of tissue perfusion and microcirculation. In this article, we evaluated LSCI in imaging perfusion in clinical oncology through a systematic review of the literature. Methods: The inclusion criterion for the literature search in PubMed, Web of Science and Scopus electronic databases was the use of LSCI in clinical oncology, meaning that all animal, phantom, ex vivo , experimental, research and development, and purely methodological studies were excluded. Results: Thirty-six articles met the inclusion criteria. The anatomic locations of the neoplasms in the selected articles were brain (5 articles), breasts (2 articles), endocrine glands (4 articles), skin (12 articles), and the gastrointestinal tract (13 articles). Conclusions: While LSCI is emerging as an appealing imaging modality, it is crucial for more clinical sites to initiate clinical trials. A lack of standardized protocols and interpretation guidelines are posing the most significant challenge.

21 September 2022 in Tomography
Verified
Journal Article
Open access
PDF file
LRLuk Rogelj
Luk Rogelj
RDRok Dolenec
Rok Dolenec
MTMartina Vivoda Tomšič
Martina Vivoda Tomšič
ELElmar Laistler
Elmar Laistler
USUrban Simončič
Urban Simončič
RHRok Hren
Rok Hren
Anatomically accurate models of a human finger can be useful in simulating various disorders. In order to have potential clinical value, such models need to include a large number of tissue types, identified by an experienced professional, and should be versatile enough to be readily tailored to specific pathologies. Magnetic resonance images were acquired at ultrahigh magnetic field (7 T) with a radio-frequency coil specially designed for finger imaging. Segmentation was carried out under the supervision of an experienced radiologist to accurately capture various tissue types (TTs). The final segmented model of the human index finger had a spatial resolution of 0.2 mm and included 6,809,600 voxels. In total, 15 TTs were identified: subcutis, Pacinian corpuscle, nerve, vein, artery, tendon, collateral ligament, volar plate, pulley A4, bone, cartilage, synovial cavity, joint capsule, epidermis and dermis. The model was applied to the conditions of arthritic joint, ruptured tendon and variations in the geometry of a finger. High-resolution magnetic resonance images along with careful segmentation proved useful in the construction of an anatomically accurate model of the human index finger. An example illustrating the utility of the model in biomedical applications is shown. As the model includes a number of tissue types, it may present a solid foundation for future simulations of various musculoskeletal disease processes in human joints.