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Dive into the research topics where Marek Chojnowski is active.

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Featured researches published by Marek Chojnowski.


Reumatologia | 2016

Capillaroscopy - a role in modern rheumatology.

Marek Chojnowski; Anna Felis-Giemza; Marzena Olesińska

Capillaroscopy is a non-invasive, easy and safe diagnostic technique designed to evaluate small vessels of the microcirculation in the nailfold. It can reveal both the general architecture of capillary rows and fine details of particular vessels. The most important indications for performing capillaroscopy include differential diagnosis of primary and secondary Raynauds phenomenon, as well as assessment of scleroderma spectrum disorders. In systemic sclerosis capillary abnormalities appear and evolve in a clearly defined sequence called the scleroderma pattern, which correlates with internal organ involvement. Capillaroscopy is also listed as a systemic sclerosis classification criterion recognized by the European League Against Rheumatism (EULAR). With digitized equipment, capillaroscopy allows for precise qualitative and quantitative evaluation of the microcirculation and is a valuable tool in the rheumatologists’ daily practice.


Archives of Medical Science | 2015

Evaluation of T-wave alternans in high-resolution ECG maps recorded during the stress test in patients after myocardial infarction

Dariusz Janusek; Michal Kania; Rajmund Zaczek; Małgorzata Kobylecka; Marek Chojnowski; Leszek Królicki; Grzegorz Opolski; Roman Maniewski

Introduction Recent studies point to analysis of T-wave alternans as a promising indicator of an increased risk of life-threatening ventricular arrhythmias. In this study the occurrence of T-wave alternans in the high-resolution ECGs recorded during the exercise stress test and scintigraphic tests (SPECT) in patients with ischemic heart disease was examined. Material and methods The study group consisted of 33 patients after myocardial infarction. In the group of patients after myocardial infarction and with low left ventricular ejection fraction correlations of 70% between the test results of T-wave alternans and SPECT and 60% between the test results of T-wave alternans and stress test were found. Results In the group of patients after myocardial infarction but with high left ventricular ejection fraction correlations were respectively 39% and 48%. The analysis of the electrocardiographic maps showed a strong dependence of this correlation on the T-wave alternans amplitude and location of the ECG measuring electrode on the chest. The results might suggest that in patients after myocardial infarction and at increased risk for sudden cardiac death T-wave alternans may also provide information about cardiac electrical instability associated with ischemia. Conclusions It can also be assumed that the position of the electrode where the highest level of the T-wave alternans was detected can indicate the location of the ischemic region of the heart.


Reumatologia | 2017

Infrared thermal imaging in connective tissue diseases

Marek Chojnowski

Infrared thermal imaging (IRT) is a non-invasive, non-contact technique which allows one to measure and visualize infrared radiation. In medicine, thermal imaging has been used for more than 50 years in various clinical settings, including Raynaud’s phenomenon and systemic sclerosis. Imaging and quantification of surface body temperature provides an indirect measure of the microcirculation’s overall performance. As such, IRT is capable of confirming the diagnosis of Raynaud’s phenomenon, and, with additional cold or heat challenge, of differentiating between the primary and secondary condition. In systemic sclerosis IRT has a potential role in assessing disease activity and monitoring treatment response. Despite certain limitations, thermal imaging can find a place in clinical practice, and with the introduction of small, low-cost infrared cameras, possibly become a part of routine rheumatological evaluation.


Reumatologia | 2016

Radionuclide synovectomy – essentials for rheumatologists

Marek Chojnowski; Anna Felis-Giemza; Małgorzata Kobylecka

Radionuclide synovectomy is a minimally invasive method of treating persistent joint inflammation. It involves intra-articular injection of radioactive colloids which induce necrosis and fibrosis of hypertrophic synovial membrane. The most common indication for radiosynovectomy is rheumatoid arthritis, although patients with seronegative spondyloarthropathies, unclassified arthritis, haemophilic arthropathy and other less common arthropathies can also benefit from this method. Radiosynovectomy is safe, well tolerated and efficacious. About 70–80% of patients respond well to the therapy. However, the therapeutic effects are considerably worse in patients with co-existent osteoarthritis and advanced joint degeneration. Despite its advantages, radionuclide synovectomy is not performed as often as it could be, so greater knowledge and understanding of this method are needed. The authors present the most important facts about radiosynovectomy that may help rheumatologists in their daily clinical practice.


Clinical Imaging | 2015

Simplified protocol of cardiac 18F-fluorodeoxyglucose positron emission tomography viability study in normoglycemic patients with known coronary artery disease ☆

Małgorzata Kobylecka; Maria Teresa Płazińska; Tomasz Mazurek; Adam Bajera; Anna Słowikowska; Katarzyna Fronczewska-Wieniawska; Marek Chojnowski; Joanna Mączewska; Marianna Bąk; Leszek Królicki

PURPOSE The purpose was to evaluate quality of 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) myocardial scans and its correlation with background glucose (BG) after simplified 5% intravenous glucose load protocol. METHODS An intravenous glucose load protocol was applied in 69 normoglycemic patients with confirmed coronary artery disease. The blood glucose level was measured every 15 min. RESULTS Eighty-four percent of images were optimal, 8.7% suboptimal, and 7.3% uninterpretable. The quality of 18F-FDG-PET was BG independent and body mass index dependent (P=.0007). CONCLUSIONS Simplified glucose load protocol is a safe and efficient method of preparation for FDG cardiac viability study in patients with normoglycemia.


Nuclear Medicine Review | 2014

Radioguided surgery in patient with pancreatic neuroendocrine tumour followed by PET/CT scan as a new approach of complete resection evaluation — case report

Jolanta Kunikowska; Maciej Słodkowski; Łukasz Koperski; Anna Kolasa; Jan Maryański; Piotr Pawliszak; Renata Matyskiel; Marek Chojnowski; Michał Najdzik; Leszek Królicki

Radioguided surgery using 68-gallium labelled somatostatin analogues is a promising method for detection of small, intra-abdominal, neuroendocrine neoplasm (NEN). However, due to high background activity (physiological uptake in e.g. spleen, adrenal glands and kidneys) tumours of the tail and body of pancreas might be impossible to detect with hand-held gamma probe. Therefore a new concept of intraoperative PET/CT scan of the resected tissue can be helpful in determining whether the tumour has been excised within the margins of healthy tissue. A 71-year-old woman with primary, non-metastatic NEN of the tail of pancreas is described. The tumour was diagnosed using MRI and PET/CT scan. Before operation patient was administered intravenously 80 MBq of ⁶⁸Ga-DOTATATE. The surgery procedure was performed 60-180 minutes post injection. During the procedure pancreas was visualized, but the tumour could not be localized neither with palpation nor gamma probe. The tail of the pancreas was resected en bloc with spleen and adjacent lymph nodes. PET/CT scan of the tissue specimen was performed immediately followed by pathological examination. PET/CT scan of the resected tissue showed moderate activity in the tail of pancreas, and a small focus of high activity in the tail. Area of high SSTR expression in the tail corresponded with preoperative findings in MRI and whole-body PET/CT. Histopathological examination of the specimen confirmed the presence of neuroendocrine tumour grade 1. Immediate PET/CT scan of the surgical specimen can bring new quality to intraoperative assessment of completeness of resection of neuroendocrine tumours.


Reumatologia | 2018

Beta burns following radionuclide synovectomy

Marek Chojnowski; Maria Teresa Płazińska; Marek Sławomir Chojnowski; Leszek Królicki

Radionuclide synovectomy (RSV) is a form of minimally invasive treatment of persistent joint inflammation. The procedure has a high safety profile and the occurrence of serious adverse events, such as full-thickness skin radiation necrosis, is rare. Less severe radiation events, while more common, are usually benign and self-limiting. We present two cases of low-grade beta burns that developed after RSV, despite proper injection technique. The potential long-term risk of such exposure is also discussed, with reference to historical radiation incidents. While low-grade beta burns after RSV usually pose little danger to the patient, any clinician involved in radionuclide treatment of arthritis should be aware of their existence and management


Nuclear Medicine Review | 2017

Radionuclide imaging and therapy in a patient with coexistent diabetic foot syndrome and psoriatic arthritis

Marek Chojnowski; Beata Mrozikiewicz-Rakowska; Małgorzata Kobylecka; Leszek Czupryniak; Leszek Królicki

We report a case of 67-year-old man suffering from psoriatic arthritis, type 2 diabetes and diabetic foot syndrome. The patient presented symptoms of inflammation of the right ankle joint. Scintigraphic imaging with radiolabeled white blood cells was performed to differentiate whether the inflammation was related to psoriatic arthritis or diabetic foot syndrome. After revealing that, the inflammatory process was restricted only to the articular space of subtalar joint, the patient was diagnosed with exacerbation of psoriatic arthritis and qualified for radionuclide synovectomy. In patients with coexistent diabetic foot syndrome and inflammatory arthritis of the foot it is of vital importance to accurately differentiate these two conditions. We conclude that this can be potentially achieved with radiolabeled white blood cells scintigraphic imaging.


Nuclear Medicine Review | 2017

Assessment of the myocardial FDG-PET image quality with the use of maximal Standardized Uptake Value myocardial to background index. Application of the results in regard to semiquantitative assessment of myocardial viability with cardiac dedicated softwar

Małgorzata Kobylecka; Tomasz Mazurek; Katarzyna Fronczewska-Wieniawska; Anna Fojt; Anna Słowikowska; Joanna Mączewska; Marek Chojnowski; Adam Bajera; Maria Teresa Płazińska; Leszek Królicki

BACKGROUND The objective of this study was to semiquantitatively assess the degree of myocardial fluorodeoxyglucose (FDG) uptake in glucose-loaded myocardial viability positron emission tomography/computed tomography (PET/CT) scans, to calculate the myocardial to background index, and correlate the index with image quality assessed on the basis of visual qualitative assessment. MATERIAL AND METHODS The myocardial FDG-PET/CT study was carried out in 69 non-diabetic patients, who had known coronary artery disease, by intravenous injection of 250 ± 70 MBq (range: 180-320 MBq) FDG. Images were interpreted visually and patients were divided into three groups according to the grade of myocardial uptake: optimal, suboptimal, and uninterpretable. Semiquantitative analysis was performed by calculating the standardized uptake value (SUVmax) for myocardium and background (blood pool) activity, and expressed as the myocardial to background (M/B) activity ratio. RESULTS On the basis of visual (qualitative) analysis, 60/69 (86.96%) patients showed optimal quality of FDG cardiac uptake, 3/69 (4.35%) were suboptimal, and uninterpretable FDG PET scan results were found in 6/69 (8.70%) patients. The M/B index was found to be significantly higher in images of optimal vs. suboptimal quality (6.87 ± 3.99 vs. 1.65 ± 0.78 respectively; p < 0.0001). CONCLUSIONS The index ratio of 2.2, which is consistent with the upper borderline value for visually uninterpretable images, was considered the cut-off value for scans of optimal and non-optimal quality.


Reumatologia | 2016

Esophageal transit scintigraphy in systemic sclerosis

Marek Chojnowski; Małgorzata Kobylecka; Marzena Olesińska

Systemic sclerosis is a rare connective tissue disease, distinctive features of which are fibrosis and microangiopathy. The esophagus is one of the most commonly involved internal organs. Most patients experience dysphagia, difficulties in swallowing and gastro-esophageal reflux. However, in up to one third of cases, the initial onset of esophageal disease may be clinically silent. There are several diagnostic modalities available for assessing both morphological and functional abnormalities of the esophagus. If structural abnormalities are suspected, endoscopy is the method of choice. Functional evaluation is best achieved with manometry. Both endoscopy and manometry are invasive techniques, with low patient acceptance. Barium-contrast study is well tolerated, but qualitative assessment of functional abnormalities is imprecise. Esophageal scintigraphy is an easy, non-invasive, sensitive and specific diagnostic modality. It can detect esophageal dysfunction even in asymptomatic patients. In patients already diagnosed with systemic sclerosis, scintigraphy is useful in evaluating severity and progression of the disease.

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Leszek Królicki

Medical University of Warsaw

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Tomasz Mazurek

Medical University of Warsaw

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Adam Bajera

Medical University of Warsaw

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Anna Słowikowska

Medical University of Warsaw

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Grzegorz Opolski

Medical University of Warsaw

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Joanna Mączewska

Medical University of Warsaw

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