Pre-procedural high-pitch coronary CT angiography assessment of patients undergoing transcatheter aortic valve implantation (TAVI) without patient-specific adjustment: analysis of diagnostic performance.

AIM: To evaluate the ability to assess the coronary arteries using pre-procedural computed tomography (CT; high-pitch mode) in patients referred for transcatheter aortic valve implantation (TAVI). METHODS AND MATERIALS: CT and invasive coronary angiography (ICA) were performed pre-TAVI in 100 patients (46 women; 79 ± 5.9 years). CT was performed in prospectively ECG-triggered high-pitch mode after intravenous administration of 70 ml iodinated contrast medium. Image quality was assessed using a four-point scale (graded 0-3). Significant coronary artery stenosis (≥50% diameter) was graded as either present or absent by one observer and in one-third of patients by two observers independently. ICA was the standard of reference. Results were reported per segment and per patient. RESULTS: Twenty-two percent of patients had known coronary artery disease (CAD). In two cases, a coronary anomaly was detected. Diagnostic image quality (grade 1-3) was achieved in 30.3% of segments. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 75%, 80.5%, 16%, and 98.5%, respectively. Significant coronary stenosis could be ruled out completely in all segments in three patients. The interrater agreement per patient was excellent (kappa = 1). CONCLUSION: Relevant coronary findings can frequently be observed in high-pitch TAVI-planning CT. Despite the limitations of the technique and in patients referred to pre-TAVI evaluation (rapid heart rate, coronary calcifications, etc.), a valid evaluation of coronary arteries is possible in a considerable proportion of segments with a high NPV; however, few studies were completely free of motion artefacts to dependably exclude CAD using this technique in this challenging group of patients.

COMPUTED TOMOGRAPHY IN DETECTING FEATURES OF CORONARY ATHEROSCLEROSIS IN DIFFERENT ETHNIC GROUPS OF KAZAKHSTAN POPULATION.

The aim of the study was to identify the features of coronary lesions and to determine the correlation between the main risk factors for coronary artery disease according to the SCORE quality of life scale and the calcium index in MSCT in different age and ethnic groups in men and women living in Kazakhstan. We retrospectively analyzed 935 case histories of patients undergoing MSCT to assess the condition of the coronary arteries. The patients were divided into three groups: Kazakhs (66.9%), Russians (21.4%) and other (11.7%) nationalities. There were statistically significant differences between ethnic groups in BMI (p=0.03), type of chest pain (p<0.01), statin use (p=0.01), and blood glucose (p<0.01). The study showed that the prevalence of coronary atherosclerosis is higher among Russians compared to Kazakhs, even after adjusting for traditional risk factors. In multivariate analysis, the calcium index values ​​were significantly higher in the group of the Russian population by 48% (OR=1.48; 95% CI 0.91-2.40) than in the Kazakh population. In the course of the cross-sectional study, statistically significant differences in the nature of coronary lesions were revealed between ethnic groups, mainly males, living in the Republic. Until now, such studies have not yet been conducted among the inhabitants of Kazakhstan, and data on the ethnic specificity of risk factors for cardiovascular diseases in this geographical region have not been sufficiently studied. Previous studies have shown that East Asians, including Chinese, Koreans, and Japanese, have a lower incidence of coronary artery disease as measured by CI compared to Europeans. A large MESA study also reported observations that study participants of Chinese nationality had a lower CI compared to Europeans. Despite significant differences in dietary habits and living in different climatic conditions between Asians of different countries, lower CI scores appear to be a racial trait of Asians, which was further confirmed by our study. These results are undoubtedly representative, as patients from different regions of Kazakhstan were treated in two clinics of republican significance. In the future, it is necessary to conduct prospective studies with subsequent follow-up of patients after treatment and in identifying the causes of recurrent coronary events, as was done in the MESA study.

High inter- and intra-observer agreement in mapping sequences compared to classical Lake Louise Criteria assessment of myocarditis by inexperienced observers.

AIM: To investigate the observer agreement for the assessment of chronic myocarditis by native T1 and T2 relaxation times, post-contrast T1 relaxation time, and extracellular volume (ECV) fraction, compared to Lake Louise Criteria: oedema ratio (OR) and early gadolinium enhancement ratio (EGEr). MATERIALS AND METHODS: Data were collected retrospectively on 71 consecutive patients who underwent cardiac magnetic resonance imaging as part of a complete diagnostic work-up according to current guidelines for suspected myocarditis. Thirteen cases were excluded due to previous myocardial infarction or technical issues. To test for intra- and interobserver agreement, the determination of the myocardial native T1 and T2 relaxation times, post-contrast T1 relaxation time, ECV, OR and EGEr was undertaken by two medical school graduates after comprehensive training. Bland-Altman analysis and intraclass correlation coefficient (ICC) were assessed. RESULTS: The final analysis included 27 patients with chronic myocarditis, 21 patients with dilated cardiomyopathy and/or hypertensive heart disease, and 10 patients with unremarkable investigations in the control group. Excellent interobserver agreement was obtained for native T1 and T2 relaxation times, post-contrast T1 relaxation time and ECV, with ICC of 0.982/0.977/0.991/0.994, p < 0.001. Interobserver agreement was lower for OR and EGEr, with ICC of 0.841 and 0.818, p < 0.001, respectively. Mapping parameters (cut-off values: T1 1,070 ms, T2 54 ms, ECV 30%) yield good performance in the diagnosis of chronic myocarditis with the best sensitivity/specificity/accuracy of 93%/80%/88% for ECV, followed by 70%/80%/74% for T2, and 52%/88%/69% for T1. CONCLUSIONS: mapping parameters show excellent agreement between observers in the assessment of myocarditis.

Free-breathing quantification of regional ventilation derived by phase-resolved functional lung (PREFUL) MRI.

PURPOSE: To test the feasibility of regional fully quantitative ventilation measurement in free breathing derived by phase-resolved functional lung (PREFUL) MRI in the supine and prone positions. In addition, the influence of T2 * relaxation time on ventilation quantification is assessed. METHODS: Twelve healthy volunteers underwent functional MRI at 1.5 T using a 2D triple-echo spoiled gradient echo sequence allowing for quantitative measurement of T2 * relaxation time. Minute ventilation (ΔV) was quantified by conventional fractional ventilation (FV) and the newly introduced regional ventilation (VR), which corrects volume errors due to image registration. ΔVFV versus ΔVVR and ΔVVR versus ΔVVR with T2 * correction were compared using Bland-Altman plots and correlation analysis. The repeatability and physiological plausibility of all measurements were tested in the supine and prone positions. RESULTS: On global and regional scales a strong correlation was observed between ΔVFV versus ΔVVR and ΔVVR versus ΔVVRT2* (r > 0.93); however, regional Bland-Altman analysis showed systematic differences (p < 0.0001). Unlike ΔVVRT2* , ΔVVR and ΔVFV showed expected physiologic anterior-posterior gradients, which decreased in the supine but not in the prone position at second measurement during 3 min in the same position. For all quantification methods a moderate repeatability (coefficient of variation <20%) of ventilation was found. CONCLUSION: A fully quantified regional ventilation measurement using ΔVVR in free breathing is feasible and shows physiologically plausible results. In contrast to conventional ΔVFV, volume errors due to image registration are eliminated with the ΔVVR approach. However, correction for the T2 * effect remains challenging.

Detection of chronic lung allograft dysfunction using ventilation-weighted Fourier decomposition MRI.

Chronic lung allograft dysfunction (CLAD) remains the leading cause of morbidity and mortality after lung transplantation. Diagnosis requires spirometric change, which becomes increasingly difficult with advancing CLAD. Fourier decomposition magnetic resonance imaging (FD-MRI) permits acquisition of ventilated-weighted images during free-breathing. This study evaluates FD-MRI in detecting CLAD in selected patients after bilateral lung transplantation (DLTx). DLTx recipients demonstrating CLAD at various stages participated. Radiologists remained blinded to clinical status until completion of image analysis. Image acquisition used a 1.5-T MR scanner using a spoiled gradient echo sequence. After FD processing and regional fractional ventilation (RFV) quantification, the volume defect percentage at 2 thresholds (VDP1,2 ), median lung RFV and quartile coefficient of dispersion (QCD) were calculated. Sixty-two patients participated. CLAD was present in 29/62 (47%) patients, of whom 17/62 (27%) had forced expiratory volume in 1 second ≤65% at image acquisition. VDP1 was higher among these participants compared to other groups (P < .001). Increased VDP1 was associated with subsequent graft loss, with values >2% showing reduced survival, independent of degree of graft dysfunction (P = .005). VDP2 discriminated between presence or absence of CLAD (area under the curve = 0.71; P = .03). QCD increased significantly with advancing disease (P < .001). In conclusion, FD-MRI-derived parameters demonstrate potential in quantitative CLAD diagnosis and assessment after DLTx.

Comparison of volumetric and functional parameters in simultaneous cardiac PET/MR: feasibility of volumetric assessment with residual activity from prior PET/CT.

OBJECTIVE: To compare cardiac left ventricular (LV) parameters in simultaneously acquired hybrid fluorine-18-fluorodeoxyglucose ([18F] FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) in patients with residual tracer activity of upstream PET/CT. METHODS: Twenty-nine patients (23 men, age 58±17 years) underwent cardiac PET/MRI either directly after a non-cardiac PET/CT with homogenous cardiac [18F] FDG uptake (n=20) or for viability assessment (n=9). Gated cardiac [18F] FDG PET and cine MR sequences were acquired simultaneously and evaluated blinded to the cross-imaging results. Image quality (IQ), end-diastolic (LVEDV), end-systolic volume (LVESV), ejection fraction (LVEF) and myocardial mass (LVMM) were measured. Pearson correlation and intraclass correlation coefficient (ICC), regression and a Bland-Altman analysis were assessed. RESULTS: Except LVMM, volumetric and functional LV parameters demonstrated high correlations (LVESV: r=0.97, LVEDV: r=0.95, LVEF: r=0.91, LVMM: r=0.87, each p<0.05), but wide limits of agreement (LOA) for LVEDV (-25.3-82.5ml); LVESV (-33.1-72.7ml); LVEF (-18.9-14.8%) and LVMM (-78.2-43.2g). Intra- and interobserver reliability were very high (ICC≥0.95) for all parameters, except for MR-LVEF (ICC=0.87). PET-IQ (0-3) was high (mean: 2.2±0.9) with significant influence on LVMM calculations only. CONCLUSION: In simultaneously acquired cardiac PET/MRI data, LVEDV, LVESV and LVEF show good agreement. However, the agreement seems to be limited if cardiac PET/MRI follows PET/CT and only the residual activity is used. KEY POINTS: • [ 18 F] FDG PET-MRI is feasible with residual [ 18 F] FDG activity in patients with homogenous cardiac uptake. • Cardiac volumes and function assessed by PET/MRI show good agreement. • LVEDV and LVESV are underestimated; PET overestimates LVMM and LVEF. • Cardiac PET and MRI data correlate better when acquired simultaneously than sequentially. • PET and MRI should not assess LV parameters interchangeably.

[Image-guided pain therapy. Sympathicolysis]. / Bildgestützte Schmerztherapie. Sympathikolyse.

BACKGROUND: In the autonomic nerve system most sympathetic neurons synapse peripherally in the ganglia of the sympathetic trunk. A reduction in sympathicotonia by partial elimination of these ganglia is a therapeutic approach that has been used for more than 100 years. In the early 1920s the first attempts at percutaneous sympathicolysis (SL) were carried out. Nowadays, minimally invasive image-guided SL has become an integral part of interventional radiology. Established indications for SL are hyperhidrosis, critical limb ischemia and the complex regional pain syndrome. METHODS: The standard imaging guidance modality in SL is computed tomography (CT) which allows the exact placement of the puncture needle in the target area under visualization of the surrounding structures. Ethanol is normally used for chemical lysis, which predominantly eliminates the unmyelinated autonomic axons. In order to visualize the distribution of the ethanol during application, iodine-containing contrast medium is added. RESULTS: The sympathetic nervous system (SNS) controls sweat secretion via the efferent neurons; therefore, effective therapy of idiopathic palmar, axillary and plantar hyperhidrosis can be achieved when SL is performed at the corresponding level of the sympathetic trunk. Furthermore, due to the vasomotor innervation of most blood vessels, by reduction of the sympathicotonus an atony of the smooth muscles and therefore vasodilatation occurs, which is used as a palliative therapeutic option in patients with critical limb ischemia. By elimination of the afferent sensory fibers this also results in pain relief. This principle is also used in the SL therapy of the complex regional pain syndrome. CONCLUSION: After the introduction of CT guidance, major complications have become rare events. In addition to the usual risks of percutaneous interventions there are, however, a number of specific complications, such as syncope caused by irritation of cardiac sympathetic nerves in thoracic SL and ureteral injury in lumbar SL.

Pericardial, intra-abdominal, and subcutaneous adipose tissue in patients with major depressive disorder.

OBJECTIVE: Major depressive disorder (MDD) is associated with an increased risk for developing coronary artery disease (CAD). Recently, pericardial adipose tissue, a metabolically active visceral fat depot surrounding the heart, has been implicated in the pathogenesis of CAD. Therefore, we investigated pericardial adipose tissue volumes in patients with MDD and compared them to healthy comparison subjects. METHOD: In this case-control study at a university medical center, 50 male and female in-patients with MDD and 25 healthy men and women were examined. The main outcome measures were the volumes of pericardial adipose tissue, intra-abdominal adipose tissue (IaAT) and subcutaneous adipose tissue (ScAT) which were measured using magnetic resonance imaging. RESULTS: The pericardial adipose tissue volumes were greater in men and women with MDD compared with the healthy comparison group following adjustments for the effects of age, weight, height, and physical activity. CONCLUSION: This study expands our knowledge about the alterations in body composition that occur in patients with MDD. The findings are highly relevant for understanding the comorbidity between heart disease and depressive disorders.

[Hybrid imaging in diagnostics and therapy of chronic myocardial ischemia. Clinical value]. / Hybridbildgebung in Diagnostik und Therapie der chronischen Myokardischämie. Klinischer Stellenwert.

Clinical studies have consistently shown that there is only a very weak correlation between the angiographically determined severity of coronary artery disease (CAD) and disturbance of regional coronary perfusion. On the other hand, the results of randomized trials with a fractional flow reserve (FFR)-guided coronary intervention (DEFER, FAME I, FAME II) showed that it is not the angiographically determined morphological severity of coronary artery disease but the functional severity determined by FFR that is critical for prognosis and the indications for revascularization. A non-invasive method combining the morphological image of the coronary anatomy with functional imaging of myocardial ischemia is therefore particularly desirable. An obvious solution is the combination of coronary computed tomography angiography (CCTA) with a functional procedure, such as perfusion positron emission tomography (PET), perfusion single photon emission computed tomography (SPECT) or perfusion magnetic resonance imaging (MRI). This can be performed with fusion imaging or with hybrid imaging using PET-CT or SPECT-CT. First trial results with PET CCTA and SPECT CCTA carried out as cardiac hybrid imaging on a 64 slice CT showed a major effect to be a decrease in the number of false positive results, significantly increasing the specificity of CCTA and SPECT. Although the results are promising, due to the previously high costs, low availability and the additional radiation exposure, current data is not yet sufficient to give clear recommendations for the use of hybrid imaging in patients with a low to intermediate risk of CAD. Ongoing prospective studies such as the SPARC or EVINCI trials will bring further clarification here.

Regional analysis of longitudinal systolic function of the right ventricle after corrective surgery of tetralogy of Fallot using myocardial isovolumetric acceleration index.

To assess regional longitudinal systolic function of the right ventricle in patients with repaired tetralogy of Fallot (TOF) by tissue Doppler imaging-derived isovolumetric acceleration (IVA) index and determine the effect of right-ventricular (RV) enlargement on regional systolic function. In 30 consecutive TOF patients and 30 age-matched controls, myocardial velocity of the RV ventricular free wall in the basal and middle regions were examined in the apical four-chamber view. Peak myocardial velocity during IVA was recorded on the free RV wall. IVA index was calculated as the difference between baseline and peak velocity divided by their time interval. In 23 of the studied TOF patients, magnetic resonance imaging was performed on the same day to determine global RV volume and ejection fraction. IVA index of the RV lateral free wall was significantly lower in the basal (8.31 ± 6.00 vs. 19.00 ± 10.85 m/s(2), p = 0.0001) and middle segments (6.56 ± 5.22 vs. 16.17 ± 7.44 m/s(2), p = 0.0001) in patients than in controls. Among TOF patients, a negative correlation was found between IVA index in the middle segment and RV end-diastolic volume/body surface area (r = -0.549, p < 0.01). Similar to other longitudinal RV wall parameters, the IVA index showed a decreased value in the RV free wall, which is related to the impaired regional and global longitudinal RV systolic dysfunction. RV enlargement adversely affects regional longitudinal systolic function.

[Cardiac magnetic resonance imaging: from imaging to diagnosis]. / Kardiale Magnetresonanztomographie: Vom Bild zur Diagnose.

Cardiac magnetic resonance imaging (CMR) has evolved over the past 20 years from a research-based imaging modality to an indispensable routine procedure in cardiac diagnostics. In addition to the morphological representation of cardiac anatomy, whereby only noninvasive multidetector computed tomography (MDCT) is superior, another strength of CMR is the assessment of cardiac function and tissue differentiation. This requires that the radiologist performing the examination and analyzing the results has good knowledge of cardiac and thoracic anatomy and a detailed knowledge of the various cardiovascular diseases, hemodynamics, and pathophysiology. CMR reliably allows determination of a range of easy to determine quantitative parameters such as ventricular ejection fraction and also the valvular regurgitation fraction, which allows objective assessment of cardiac function. Especially the possibility to differentiate inflamed, viable, and ischemic tissue using adenosine stress MRI in the last 10 years has led to routine use of CMR. Even compared to competing nuclear medicine procedures, CMR is important for treatment decision-making and for prognosis estimation, thus, making it an indispensable component of cardiovascular diagnostics.

[MRI for myocarditis]. / MRT bei Myokarditis.

Cardiovascular magnetic resonance imaging (CMRI) has become the primary tool for the non-invasive assessment in patients with suspected myocarditis, especially after exclusion of acute coronary syndrome (ACS) for the differential diagnosis. Various MRI parameters are available which have different accuracies. Volumetric and functional ventricular assessment and the occurrence of pericardial effusion alone demonstrate only a poor sensitivity and specificity. The calculation of the T2-ratio (edema assessment), the early or global relative myocardial enhancement (gRE) and the late gadolinium enhancement (LGE), which represents irreversibly injured myocardium, are more specific parameters. All MRI parameters demonstrate the best accuracy in infarct-like acute myocarditis, whereas in chronic myocarditis sensitivity and specificity are less accurate. Therefore, a multisequential (at least two out of three parameters are positive) approach is recommended. The assessment of the value of newer, more quantitative MRI sequences, such as T1 and T2-mapping is still under investigation.

[Imaging prior to transcatheter aortic valve implantation]. / Bildgebung vor Transkatheteraortenklappenersatz.

Percutaneous transcatheter aortic valve implantation (TAVI) is an established alternative to open heart surgery in patients with severe aortic stenosis (AS) unsuitable for conventional aortic valve replacement due to comorbidities with a high perioperative risk or contraindications. Preprocedural imaging plays a major role for adequate determination of indications and prosthesis selection, prosthesis sizing and therefore for a reduction of periprocedural complications. Besides Doppler echocardiography which is mainly used for grading of the severity of aortic valve stenosis and peri-interventional imaging, cardiac computed tomography (CCT) is the imaging modality of choice. The CCT procedure not only allows for reliably assessment and measuring of the complex 3-dimensional geometry of the aortic root but also for the aorta and the peripheral vessels used as potential access paths.

[German Radiological Society and the Professional Association of German Radiologists position paper on coronary computed tomography: clinical evidence and quality of patient care in chronic coronary syndrome]. / Positionspapier von DRG und BDR zur Computertomographie des Herzens: Klinische Evidenz und Versorgungsqualität beim chronischen Koronarsyndrom.

This position paper is a joint statement of the German Radiological Society (DRG) and the Professional Association of German Radiologists (BDR), which reflects the current state of knowledge about coronary computed tomography (CT). It is based on preclinical and clinical studies that have investigated the clinical relevance as well as the technical requirements and fundamentals of cardiac computed tomography.

[Diagnostic work-up of coronary artery disease: Clinical value of different imaging methods]. / Diagnostik der koronaren Herzkrankheit : Stellenwert der verschiedenen bildgebenden Verfahren.

This continuing medical education (CME) article describes the different non-invasive imaging methods with the exception of positron emission tomography for ischemia and viability testing. While stress methods, such as myocardial scintigraphy, stress echo or stress magnetic resonance imaging can detect the functional relevance of coronary artery stenosis, multislice computed tomography allows the visualization of the coronary anatomy and potential stenoses. Recently developed hybrid imaging allows the coronary anatomy and simultaneous functional testing of ischemia to be depicted. The different imaging methods for ischemia and viability testing are described.

Diffusion tensor imaging and tractography for assessment of renal allograft dysfunction-initial results.

OBJECTIVES: To evaluate MR diffusion tensor imaging (DTI) as non-invasive diagnostic tool for detection of acute and chronic allograft dysfunction and changes of organ microstructure. METHODS: 15 kidney transplanted patients with allograft dysfunction and 14 healthy volunteers were examined using a fat-saturated echo-planar DTI-sequence at 1.5 T (6 diffusion directions, b = 0, 600 s/mm²). Mean apparent diffusion coefficient (ADC) and mean fractional anisotropy (FA) were calculated separately for the cortex and for the medulla and compared between healthy and transplanted kidneys. Furthermore, the correlation between diffusion parameters and estimated GFR was determined. RESULTS: The ADC in the cortex and in the medulla were lower in transplanted than in healthy kidneys (p < 0.01). Differences were more distinct for FA, especially in the renal medulla, with a significant reduction in allografts (p < 0.001). Furthermore, in transplanted patients a correlation between mean FA in the medulla and estimated GFR was observed (r = 0.72, p < 0.01). Tractography visualized changes in renal microstructure in patients with impaired allograft function. CONCLUSIONS: Changes in allograft function and microstructure can be detected and quantified using DTI. However, to prove the value of DTI for standard clinical application especially correlation of imaging findings and biopsy results is necessary.

Computer tomography assessment of pedicle screw placement in lumbar and sacral spine: comparison between free-hand and O-arm based navigation techniques.

Transpedicular screw fixation has been accepted worldwide since Harrington et al. first placed pedicle screws through the isthmus. In vivo and in vitro studies indicated that pedicle screw insertion accuracy could be significantly improved with image-assisted systems compared with conventional approaches. The O-arm is a new generation intraoperative imaging system designed without compromise to address the needs of a modern OR like no other system currently available. The aim of our study was to check the accuracy of O-arm based and S7-navigated pedicle screw implants in comparison to free-hand technique described by Roy-Camille at the lumbar and sacral spine using CT scans. The material of this study was divided into two groups, free-hand group (group I) (30 patients; 152 screws) and O-arm group (37 patients; 187 screws). The patients were operated upon from January to September 2009. Screw implantation was performed during PLIF or TLIF mainly for spondylolisthesis, osteochondritis and post-laminectomy syndrome. The accuracy rate in our work was 94.1% in the free-hand group compared to 99% in the O-arm navigated group. Thus it was concluded that free-hand technique will only be safe and accurate when it is in the hands of an experienced surgeon and the accuracy of screw placement with O-arm can reach 100%.

[Preoperative and postoperative imaging in patients with transposition of the great arteries]. / Prä- und Postoperative Bildgebung bei Patienten mit Transposition der großen Gefäße.

Transposition of the great arteries (TGA) is a rare disease representing not more than 3-5% of all congenital heart diseases. TGA is a cardiac anomaly in which the aorta arises entirely or largely from the morphological right ventricle and the pulmonary artery from the morphological left ventricle. This is called a ventriculo-arterial discordant connection and when accompanied by an atrio-ventricular concordant connection it is called a complete or D-transposition (D-TGA). The terms congenitally corrected TGA (ccTGA) or L-TGA describe an atrio-ventricular discordant connection. In D-TGA survival can only be achieved if additional shunting is simultaneously present, which possibly has to be created post-natal by the so-called Rashkind maneuver.Nowadays, an early anatomic correction using the arterial switch operation is the treatment of choice. Up to the 1980s, an atrial switch operation according to Senning/Mustard was performed. Apart from echocardiography the imaging modality of choice is usually MRI to assess the complex postoperative anatomy, viability of the myocardium and to perform a volumetric and functional assessment, including MR flow measurements. Multidetector computed tomography (MDCT) is used if there are contraindications to MRI or if an assessment of cardiac and especially coronary anatomy is the main interest.

[Nora's lesion. Discussion of a rare bone proliferation]. / Die Nora-Läsion. Diskussion einer seltenen Knochenproliferation.

Nora's lesion, also known as "bizarre parosteal osteochondromatous proliferation" (BPOP), was first described in 1983 by the pathologist Nora. This lesion is defined as a proliferation of the bone. In most cases the lesion emanates from the intact cortical substance of short bones. It used to be assigned to reactive, heterotopic ossifications. More recent publications described constant genetic alterations supposing a tumorous genesis. Nora lesions are mostly found in the third or fourth decade of life; a preference of sexes is not described in the literature. They are characterized by a typical appearance in radiological diagnostics, but the diagnosis is ultimately determined by histopathological examination. Surgical resection is the therapy of choice.We report the case of a 29-year-old patient with an undetermined proliferation of the proximal ulna. The diagnosis of a Nora's lesion was made. The therapeutic approach, differential diagnosis and corresponding literature are presented and discussed.