Comparing the Healing Abilities of Fluorapatite and Hydroxyapatite Ceramics in Regenerating Bone Tissue: An In Vivo Study.

Some reports in the literature show the advantages of fluoride-containing apatite ceramics over hydroxyapatite (HAP), at least in some aspects. While HAP has been used extensively in the treatment of bone defects, fluoridated apatite has hardly been tested in vivo. In order to verify the biological properties of fluoride-doped apatite and to assess its therapeutic potential, we synthesized fluorapatite (FAP) and applied it as a filling in bone defects of experimental animals (rabbits). The treatment effects were evaluated on extracted bones after 3 and 6 months from implantation using peripheral quantitative computed tomography (pQCT), dual-energy X-ray absorptiometry (DXA), radiography (X-ray) and histological staining. The study proved the integration between FAP and the bone tissue, thus indicating its stimulating effect on new bone formation and mineralization. The results achieved after 3 months of treatment were difficult to interpret unequivocally and suggested the transient delay in FAP integration of bone in comparison with HAP. The reasons for this phenomenon are unclear. Most likely, these differences between FAP and HAP resulted mainly from the different porosities, densities and ionic reactivity of the ceramics, which in our opinion affected their solubility, integration and degree of bone tissue resorption. However, it was shown that 6 months after implantation, similar level of bone defect regeneration was achieved for both FAP and HAP. In this article, we present our hypothesis concerning the basis of this phenomenon.

Diagnostic value of chest CT scanning for determination of Covid-19 severity in individual lung lobes.

INTRODUCTION AND OBJECTIVE: CT examination is an important diagnostic tool in assessment of the severity of the infection and course of the disease. The aim of the study was to evaluate the degree and frequency of involvement of individual lung lobes and the population Lobe Involvement Coefficient (pLIC) value in the investigated population. MATERIAL AND METHODS: The analyzed material comprised 124 patients aged 18-92 years. CT examinations were performed using a 16- and 32-row CT LightSpeed apparatus. The spatial distribution of typical Covid -19 pathological changes was analyzed, divided into five lung lobes. The degree of the severity of lobe involvement was assessed using counters and percentages, as well as the population Lobe Involvement Coefficient (pLIC). Statistical analysis of data was performed with the use of Statistica 10.0 software. Values were measured on an oridinal scale. Anova Friedman's test was used to compare lobes. RESULTS: Statistically significant differences in the involvement between most of the individual lobes were shown. There was no statistically significant difference in the degree of lobe involvement between the left and right upper lobes, nor in the left and right lower lobes. The highest pILC was demonstrated for the lower lobe and the lowest value was obtained for the middle lobe. CONCLUSIONS: The lower lobes were affected most frequently and most severely, with no statistical difference between the right and left sides. The middle lobe was affected relatively least frequently and lightly. The introduced pLIC index allows quantitative assessment of individual lobes involvement in relation to the entire studied population.

Computed Tomography Diagnostic of Uncommon Case of Osteopetrosis in 80-Year-Old Man-Case Report.

Background and Objectives: During osteopetrosis course, impaired bone remodeling induces skeletal osteosclerosis and abnormally dense bones, which, however, are brittle and susceptible to low-energy fractures. In this study, radiological evaluation and densitometric measurements of several bones of the skeleton in one of the oldest patients in the world suffering from osteopetrosis was presented. Materials and Methods: Volumetric bone mineral density measurements of the examined bones in an 80-year-old man were performed using two different quantitative computed tomography techniques. Results: The obtained results show higher values of the volumetric bone mineral density of the trabecular bone in lumbar spine than in the cortical bone compartment. T-score and Z-score in this patient reached values of 27-28 and 31-32, respectively. Conclusions: The obtained densitometric data may serve for further diagnostic purposes of osteopetrosis. As documented, the severity of the osteosclerotic changes of bones were higher in this patient than in most other described cases. Moreover, radiological signs diagnosed in this patient were characteristic for all types of osteopetrosis making this case very uncommon.

Perfusion CT - A novel quantitative and qualitative imaging biomarker in gastric cancer.

OBJECTIVES: The aim of this research was to examine whether Perfusion Computed Tomography (P-CT) can qualitatively and quantitatively help detect gastric cancer neoangiogenesis in vivo as well as treatment response evaluation. We attempted to explore which P-CT parameters are best used in neoangiogenesis and neoadjuvant therapy for most effective evaluation. We also tried to recognize a positive prediction value of P-CT in early responders and non-responders patients identification. MATERIALS AND METHODS: Twenty-four patients with positive biopsy results and/or clinically proven gastric cancer were enrolled in the P-CT exam. Patients were qualified for systemic treatment (16 patients received chemotherapy and 8 patients received radiochemotherapy). The baseline Perfusion-CT exam and after neoadjuvant treatment Perfusion-CT exam were conducted using a 64-row GE tomograph based on a deconvolution model in first-pass protocol perfusion. The P-CT examined the following parameters: Blood Flow (BF), Blood Volume (BV), Mean Transit Time (MTT) and Permeability Surface (PS). Positive clinical response to neoadjuvant treatment (CHT and RCT) was defined as tumor size reduction 25% or more. RESULTS: Tumor dimension reduction after neoadjuvant therapy was significantly correlated with the BF and the PS. Neoadjuvant therapy was more effective for patients with higher output BF and PS values. We did not register a significant relationship between BV and MTT parameters and tumor dimension reduction. Patients with a positive treatment response showed a decrease in BF, BV and PS perfusion parameters with an increase in MTT. CONCLUSIONS: P-CT examination allows a noninvasive neoangiogenesis assessment in vivo, leading to early identification of responding and non-responding patients. As a standard procedure, a full evaluation of treatment response should include a P-CT exam assessing neoangiogenesis.

Diagnostic difficulties resulting from morphological image variation in spondylodiscitis MR imaging.

BACKGROUND: Spinal infection (discitis; spondylodiscitis) presents a wide spectrum of pathologies. The method of choice for spondylodiscitis imaging is magnetic resonance (MR). It provides detailed anatomical information, especially concerning epidural space and spinal cord. The main aim of this article is the description and evaluation of spondylodiscitis morphological variation visible in magnetic resonance imaging. MATERIAL/METHODS: In this article we retrospectively analysed the patients diagnosed at the Department of Radiology of the Provincial Hospital No 2 in Rzeszów between October 2009 and October 2011. The subjects involved a group of five women aged 41-74 (mean 56.3 years) and eight men aged 46-69 (mean 61,3 years). All patients had spondylodiscitis symptoms. All patients underwent MRI examination before and after the contrast enhancement. In three patients additional CT examination was performed. RESULTS: Following the MRI procedure all patients were diagnosed with typical symptoms of spondylodiscitis. It also revealed a number of pathologies resulting from morphological spondylodiscitis variation. Other pathologies found on the MR images of the study group patients involved epidural intra-canal spinal pathological masses causing spinal cord compression, lung abscess, pyothorax, paravertebral abscesses and epidural empyemas, abscess between adjacent vertebral bodies, abscesses beneath anterior longitudinal ligament, and iliopsoas muscle abscesses. In all cases a destruction of vertebral bodies with end plates loss restriction and cortical layer discontinuity was observed. Moreover, one person was diagnosed with pathological vertebral body fractures and liquefactive necrosis of the vertebral body. CONCLUSIONS: Spondylodiscitis manifests itself in a great number of morphological variations visible on the radiological images. Apart from ordinary features of vertebral bodies and discs, progressive spinal destruction is observed together with reactive bone changes and soft tissue infiltration. The latter leads to a number of complications e.g. abscesses or even fistulas and also to the formation of obstacles in radiological images. The knowledge of radiological images together with overall evaluation of clinical and laboratory features enables a proper diagnosis.