Category Archives: Thesis

The influence of BMI and smoking at disease onset on long-term joint damage measured with the RAAD score in patients with rheumatoid arthritis






Introduction: after the development of new effective medication and the introduction of “treat-to-target” strategies directed at obtaining remission, the prognosis of RA greatly improved. Remarkably, obesity is named as a predictor of less radiographic progression. The literature is not clear about the relation between body mass index (BMI) and long-term joint damage. Little evidence about the long-term effect of smoking on joint damage is available. Time consuming radiographic scoring methods, such as the Sharp van der Heijde (SHS) and Larsen score, are frequently used in clinical research to evaluate joint damage of hands and feet. In order to have an easy applicable instrument to measure joint damage, Zijlstra et al. developed the RAAD score in 2002. A high correlation between the RAAD score and the SHS has been found. The present study investigated whether BMI and smoking at the moment of diagnosis are related with irreversible joint damage at long-term, measured with the RAAD score.
Patients and methods: the research population consists of all patients who received treatment for RA in the ZGT from January 1996 until December 2015. From this population patients with a RAAD score, determined between 2014 and April the first of 2016, and a disease duration of at least five years at the moment of the RAAD score were included. Baseline data were collected through retrospective record research and through verifying information during an outpatient visit. Smoking at disease onset was categorized in three groups: current smoker, former smoker, non smoker. Mann Whitney U tests, Spearman’s correlations, Kruskal-Wallis tests and multivariate regression analysis were performed.
Results: baseline characteristics study population (n=521): 67.8% woman, mean (SD) age in years 49.0 (13.7), mean (SD) BMI in kg/m2 25.7 (3.9), 79.5% RF positive, 72.6% anti-CCP positive, 36.8% non smoker, 28.4% former smoker, 34.8% smoker. Median [IQR] RAAD score was 2.0 [0-6.0]. A significant, weak correlation between BMI and the RAAD score (correlation coefficient -0.14, p=0.003) was found. No significant difference in RAAD score was found between patients with different smoking status. Obviously, the RAAD score was correlated with disease duration, irreversible damage can only increase. Disease duration was correlated with BMI. There was an increasing trend in BMI at disease during the decades. When corrected for this trend, through adjusting for disease duration, no significant correlation was found between BMI and the RAAD score.
Conclusion: BMI and smoking status at the moment of diagnosis of RA are not related with irreversible joint damage at long-term as measured with the RAAD score, when adjusted for disease duration. For the trend in BMI throughout the decades was corrected with disease duration. Continue reading

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The effect of mutant SOD1 on cell viability






Mutations in the gene encoding for superoxide dismutase 1 (mSOD1) lead to protein aggregation and
are associated with 20% of familial amyotrophic lateral sclerosis (ALS) cases. Multiple molecular
chaperones are known to influence mSOD1 aggregation and… Continue reading






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Implementation of a transcutaneous bilirubinometer in a newborn nursery : A randomized Controlled Trial






Objective: The aim of this study is to provide quantitative data on the reduction of blood sampling when using transcutaneous bilirubinometry to assess hyperbilirubinemia in healthy jaundiced newborns.
Study-design: In a randomized controlled trial in jaundiced infants (≥36 weeks gestational age) in a Dutch newborn nursery ward, the need for total serum bilirubin (TSB) measurement to determine hyperbilirubinemia was assessed by either a transcutaneous bilirubin (TcB) measurement (JM-103) (intervention group) or visual assessment of jaundice (control group). When TcB was within 50μmol/L below the threshold for phototherapy on the bilirubin nomogram, a TSB was obtained.
Results: A total of 254 neonates were randomized to either the intervention group (n=127) or the control group (n = 127). In the intervention group 43 neonates (33.9%) needed one or more TSB measurements taken versus 85 neonates (66.9%) in the control group (difference 33.0; 95% CI 21.4 to 44.6, P = Continue reading






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Het effect van interventie op de orthostatische bloeddruk profielen van syncope patiënten die zich presenteren op de spoedeisende hulp.






Introduction Orthostatic hypotension is a common cause of syncope at the emergency department (ED). Frequently an intervention is started for example intravenous fluid or medication. Recent studies described different orthostatic blood pressure recovery patterns visualized by a non-invasive beat-to-beat blood pressure monitor (Nexfin®). However, until now no research has been conducted about the effect of an intervention started at the ED on orthostatic blood pressure recovery patterns.
Objective To evaluate the effect of intervention on orthostatic blood pressure recovery patterns of syncope patients at the ED. Besides, we want to determine if it’s better to detect the effect of an intervention with Nexfin® or with the conventional intermittent blood pressure method (cBD).
Material and Methods During 14 weeks 30 patients ≥18 years were included with (pre)syncope at the ED and they were randomized in two groups. At both groups the blood pressure was measured at the ED and the outside department in lying and standing position with the cBD and in group 1 also with the Nexfin® simultaneously.
Results In the group of patients who received an intervention 71% showed a recovered blood pressure pattern at the outpatient department, in comparison to 20% of the patients who did not receive an intervention (p = 0,05). The Nexfin® also detected significantly more patients with an abnormal blood pressure recovery pattern (p = 0,03) in comparison to the cBD.
Conclusion Despite the small study population it appears that an intervention results into normalization of orthostatic blood pressure recovery patterns. Beside this we also found that the Nexfin® detected more abnormal orthostatic blood pressure recovery patterns in comparison to the cBD. Continue reading






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The diagnostic application of sonication on heart valves with suspected infective endocarditis






Introduction: Infective endocarditis (IE) is a very serious disease. Although relatively uncommon (5-11 per 100,000 people per year), it is associated with a high mortality and morbidity. The infection is predominantly caused by bacteria. However, in 10-20% of cases no causative organism is identified. This is a serious limitation to the ability of clinicians to provide the afflicted patients with optimal treatment.
Infected heart valves may become damaged through the disease process, resulting in impaired functioning. Valves affected by IE may require surgical replacement. An explanted heart valve may provide important additional opportunity to obtain information pertaining to the causative microorganism, particularly in cases of blood culture-negative IE. However, standard microbiological tests on explanted heart valves frequently lead to negative results (up to 49%). An increase in sensitivity for the detection of microorganisms would be beneficial to the diagnosis and treatment of IE.
Sonication has demonstrated an increased microbiological yield when carried out on various prosthetic materials that were suspect for infection, mainly in prosthetic joint infections. The added value is particularly apparent in material cultures of patients that were receiving prior antimicrobial therapy. It is hypothesized that similar added value may be seen when applied to explanted (prosthetic or native) heart valves.
Methods: Through a prospective case-control study, the results obtained from the experimental sonication protocol were compared to the results of the standard diagnostic protocol for explanted cardiac material. Results were obtained through cultures on agar plates, inoculation of aerobic and anaerobic blood culture bottles, and 16S PCRs. The sonication tests were always done after the standard workup, avoiding interference with regular diagnostics necessary for the clinics. Explanted valves with no suspicion of IE were used as negative controls, in order to assess the reliability of the method.
Based on a power analysis for dependent samples with α=0.05, β=0.80, and d=0.3, the necessary number of valves was determined to be n=16. Based on the UMCG’s records, the expected time needed to collect 16 valves per study group would exceed 1 year. The project was set up as a pilot study in order to evaluate and optimise the proposed study protocol, and to start with the collection of patient data. The results presented in this report are therefore limited to the number of valves collected within a 3 month period, between 01-04-2016 and 01-07-2016.
Results: Fourteen valves were included, of which 7 were suspected of IE. Polymerase chain reaction (PCR) methods identified microbial deoxyribonucleic acid (DNA) from present microorganisms on 4 of these valves. Cultures identified the presence of viable microorganisms on 2 of these valves. All negative control valves showed no evidence of microbial presence according the standard diagnostic method and the sonication protocol.
Notably, there was one clinical case that illustrates the potential for sonication as an addition to the standard workup for explanted valves from patients with IE, by making a significant contribution to the diagnosis and resulting therapy. Indeed, only sonication was able to demonstrate the presence of viable Propionibacterium acnes (P. acnes) in this case of culture-negative IE. The presence of P. acnes was confirmed by 16S PCR on the heart valve.
Conclusion: Based on the currently available data there is insufficient evidence to draw definite conclusions, though initial results are promising. However, this project enabled me to carefully formulate and validate a standard operating procedure (SOP) for the sonication of heart valves in the microbiology laboratory. This method has demonstrated the ability to
2
detect the presence of microorganisms. In one case sonication demonstrated additive value by detecting the presence of a bacterium through cultures that was not cultured using the standard diagnostic protocol, allowing for antibiotic susceptibility testing, which is crucial for final patient treatment. This finding suggests that there seems to be benefit to the detection of microorganisms by using sonication. Continuation of data collection will be needed to provide conclusive evidence. Continue reading






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The diagnostic application of sonication on heart valves with suspected infective endocarditis






Introduction: Infective endocarditis (IE) is a very serious disease. Although relatively uncommon (5-11 per 100,000 people per year), it is associated with a high mortality and morbidity. The infection is predominantly caused by bacteria. However, in 10-20% of cases no causative organism is identified. This is a serious limitation to the ability of clinicians to provide the afflicted patients with optimal treatment.
Infected heart valves may become damaged through the disease process, resulting in impaired functioning. Valves affected by IE may require surgical replacement. An explanted heart valve may provide important additional opportunity to obtain information pertaining to the causative microorganism, particularly in cases of blood culture-negative IE. However, standard microbiological tests on explanted heart valves frequently lead to negative results (up to 49%). An increase in sensitivity for the detection of microorganisms would be beneficial to the diagnosis and treatment of IE.
Sonication has demonstrated an increased microbiological yield when carried out on various prosthetic materials that were suspect for infection, mainly in prosthetic joint infections. The added value is particularly apparent in material cultures of patients that were receiving prior antimicrobial therapy. It is hypothesized that similar added value may be seen when applied to explanted (prosthetic or native) heart valves.
Methods: Through a prospective case-control study, the results obtained from the experimental sonication protocol were compared to the results of the standard diagnostic protocol for explanted cardiac material. Results were obtained through cultures on agar plates, inoculation of aerobic and anaerobic blood culture bottles, and 16S PCRs. The sonication tests were always done after the standard workup, avoiding interference with regular diagnostics necessary for the clinics. Explanted valves with no suspicion of IE were used as negative controls, in order to assess the reliability of the method.
Based on a power analysis for dependent samples with α=0.05, β=0.80, and d=0.3, the necessary number of valves was determined to be n=16. Based on the UMCG’s records, the expected time needed to collect 16 valves per study group would exceed 1 year. The project was set up as a pilot study in order to evaluate and optimise the proposed study protocol, and to start with the collection of patient data. The results presented in this report are therefore limited to the number of valves collected within a 3 month period, between 01-04-2016 and 01-07-2016.
Results: Fourteen valves were included, of which 7 were suspected of IE. Polymerase chain reaction (PCR) methods identified microbial deoxyribonucleic acid (DNA) from present microorganisms on 4 of these valves. Cultures identified the presence of viable microorganisms on 2 of these valves. All negative control valves showed no evidence of microbial presence according the standard diagnostic method and the sonication protocol.
Notably, there was one clinical case that illustrates the potential for sonication as an addition to the standard workup for explanted valves from patients with IE, by making a significant contribution to the diagnosis and resulting therapy. Indeed, only sonication was able to demonstrate the presence of viable Propionibacterium acnes (P. acnes) in this case of culture-negative IE. The presence of P. acnes was confirmed by 16S PCR on the heart valve.
Conclusion: Based on the currently available data there is insufficient evidence to draw definite conclusions, though initial results are promising. However, this project enabled me to carefully formulate and validate a standard operating procedure (SOP) for the sonication of heart valves in the microbiology laboratory. This method has demonstrated the ability to
2
detect the presence of microorganisms. In one case sonication demonstrated additive value by detecting the presence of a bacterium through cultures that was not cultured using the standard diagnostic protocol, allowing for antibiotic susceptibility testing, which is crucial for final patient treatment. This finding suggests that there seems to be benefit to the detection of microorganisms by using sonication. Continuation of data collection will be needed to provide conclusive evidence. Continue reading






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Informatievoorziening en communicatie rondom chemotherapie :Mogelijke verbeteringen in de informatievoorziening en communicatie met patiënten die chemotherapie krijgen in het Medisch Spectrum Twente.






Background: In the care around cancer patients receiving chemotherapy, it is important to provide good information and effective communication: this leads to fewer mental health problems, aproved ability to cope with diagnosis and treatment, better self-care and higher overall satisfaction. Objective: This study examines which aspects of information and communication to patients receiving chemotherapy for the first time at the Medisch Spectrum Twente (MST) can be improved by evaluating which information and communication needs exist and to which extent these needs are met.
Methods: We conducted a research consisting of a prospective and retrospective studyline. In the prospective studyline, a total of 30 patients, that got their first chemotherapy treatment in the period between 15 February 2016 and 10 June 2016, completed a questionnaire based on the QUOTEchemo-Importance before the start of their treatment. After their first chemotherapy cycle, they completed a questionnaire based on the QUOTEchemo-Performance. In the retrospective studyline, 52 patients who received chemotherapy for the first time in 2015, completed the two questionnaires at once. Both questionnaires have been developed and validated to measure information and communication needs and experiences around chemotherapy treatment. Results: Patients attached most importance to aspects associated with ‘prognosis’, ‘treatment-related information’and ‘affective communication’. Almost all aspects of information and communication can be improved. The greatest potential for improvement was found for the aspects associated with ‘coping information’, ‘interpersonal communication’ and ‘alternative sources of information’.
Conclusion: In general, the patiens are satisfied with the information and communication around their treatment. However, there is room for improvement in different areas. In particular, there is a clear need for improvement regarding the attention for wishes, questions and support needs of relatives of the patient. The same applies to the assistence that is provided in finding reliable websites. When dealing with their illness and treatment, patients would like to get more support from the caretakers in the form of information on psychosocial care and support groups. They also like to see improvement in possibilities that are available to discuss concerns, fears and emotions. Continue reading






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Impact and outcome of abnormal loading on the right ventricle in children and adults with repaired tetralogy of Fallot






1. Cross-sectional study Right ventricular remodeling in response to abnormal loading in repaired tetralogy of Fallot. Aims The long-term outcome of repaired tetralogy of Fallot (TOF) depends on multiple factors, including the pathophysiological remod… Continue reading






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het bouwen en valideren van een opstelling om de contrastgevoeligheid bij hoge lichtniveaus te meten : Een pilotstudy






Glaucoma is a chronic progressive eye disease which causes damage to the optic nerve. It could lead to blindness if left untreated. Many glaucoma patients complain of seeing in low, high and changing light conditions. Recent research focused on the lo… Continue reading






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Ashy Dermatose – de histopathologische inter-observer correlatie






Background and objectives Ashy Dermatosis (AD) is a rare pigment disorder clinically characterized by ‘ash –gray’ discoloration of the skin. It is an acquired slowly progressive, persistent skin disease of unknown etiology. There is no well proven effective treatment. It is cosmetically very disturbing for patients. The aim of this study is to clarify the histopathology of AD, because in that part little research has been done. We want to investigate if we can identify a clear histopathological pattern by an inter-observer correlation analysis.
Material and methods Three dermatologists and one pathologist, all specialized in dermatopathology and/or pigment disorders, reviewed 54 skin biopsies from patients who were previously diagnosed with AD. The observers scored histopathological characteristics and gave the most suspect diagnosis. The location of biopsy was reported only, the clinical symptoms and differential diagnosis were not mentioned. The inter-observer correlation is measured by pair-wise similarities and multirater Fleiss’ Kappa.
Results 81.5% of the included patients were female. Skin type IV and V were most common. The ages ranged between 16 and 73 years. The Fleiss’ kappa for diagnosis was 0.18 which can be interpreted as a ‘slight’ correlation. In many biopsies other diagnoses seemed more likely than AD. The percentage of pairwise similarities for assessing characteristics was between 61 and 96 % with kappa values between -0.01 and 0.41 (bad to reasonable agreements) except for ‘subepidermal fibrosis’ (35% pairwise agreement and κ = -0.33). In only four cases they all agreed AD as the pathology conclusion. They scored respectively 28, 27, 14 and 28 times AD as diagnosis. The characteristics of these cases were displayed graphically per observer. The average AD case had pigment-incontinence, superficial lymfohistiocytair perivascular infiltrate and mild vacuolization of the basal cell layer. Epidermal atrophy, hyperkeratosis and exocytosis of lymphocytes could be quite possible. The presence of civatte bodies differed per observer.
Conclusion It appears that there was no unilateral agreement of histopathological pattern for AD according to the observers. They often set other criteria and pointed different biopies as AD. But they also differ in scoring histological characteristics, which is an interesting finding for histopathological diagnosing in general. The absence of clinic and differential diagnosis is apparently important for a proper diagnosis of this skin disorder. A clear criterium for histopathology is necessary in future. It seems to be a ‘diagnosis per exclusionem’ right now. When it has anamnestic no triggers, it persists, is resistant for treatment and pathology seems not only conform but also closes out other disease, it can be diagnosed as AD. Continue reading






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Prevalence of Psychiatric Comorbidities among Women Undergoing Autologous Breast Reconstruction






Background. Patients undergoing mastectomy and autologous breast reconstruction (BR)
are required to have sufficient and long-lasting coping mechanisms. Although mental health
problems are a widespread problem in the United States, information regarding the
prevalence of psychiatric diagnosis among this patient group is lacking.
Methods. Retrospective analysis was performed using data from a large tertiary teaching
hospital. Additionally, this was compared to nationwide data provided by the Nationwide
Inpatient Sample (NIS) database. Patients undergoing autologous BR were included and
divided into different psychiatric diagnosis groups. Prevalence of each disorder, the moment
of diagnosis, and data per age group were reviewed.
Results. In total, 26,804 patients (2008 – 2012) were included in the comparison of
institutional data and nationwide data. Pre-operative, 15.3% of the patients were diagnosed
with a psychiatric disorder within the institutional database, and 17.6% in the NIS database.
There was no significant difference in prevalence between the two databases.
For the analysis of moment of diagnosis and different age groups, institutional data from 817
patients (2004 – 2014) was utilized. Post-operative, an additional 20.5% of the patients were
diagnosed with one or more psychiatric disorder. No major differences in prevalence preoperative
were seen between the age groups. Women ≤ 39 year old showed the highest
increase of prevalence post-operative.
Conclusions. Approximately one in six patients were diagnosed with a psychiatric
comorbidity before autologous breast reconstruction. Post-operative, an additional 20.5%
developed a psychiatric disorder. There was no difference in prevalence and moment of
diagnosis between the age groups. Continue reading






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Metabolic syndrome after liver transplantation : Differences in the occurrence of metabolic syndrome between patients treated with a calcineurin inhibitor and patients treated with an mTOR inhibitor after liver transplantation






Introduction: The proportion of patients with metabolic syndrome (MetS) after orthotopic
liver transplantation (OLT) is substantial higher compared to the general population. MetS
consists of a cluster of obesity, raised glucose, raised triglycerides, reduced High-Density
Lipoproteins and raised blood pressure, which is associated with an increased risk of
cardiovascular disease, diabetes mellitus and liver steatosis. The difference in prevalence might
among other things be attributed to the use of immunosuppressants.
Objectives: The main goal was to investigate whether there is a difference in occurrence of
MetS after OLT between patients treated with a calcineurin inhibitor (CNi) and patients treated
with an mTOR inhibitor (mTORi), two common used immunosuppressive drugs. In addition,
the responsible components for the development and disappearance of MetS were studied.
Methods: In this retrospective study, patients who underwent an OLT between 2006 and 2012
at the Universitätsklinikum Münster were observed. The MetS status (no MetS, new developed
MetS, persistent MetS and disappeared MetS) was determined at baseline (T0), one (T1), three
(T3), five (T5) and eight (T8) years after OLT. In addition, the responsible components for the
development and disappearance of MetS were determined. Patients who were continuously
treated with a CNi were compared with patients who were switched from a CNi to an mTORi.
At baseline, all patients were evaluated in the continuous CNi group.
Results: In total, 134 patients were included in this study. The incidence of MetS in the
continuous CNi group was 18.8%, 12.8%, 14.3% and 50.0%, while the incidence in the mTORi
switchers group was 47.8%, 23.8%, 23.1% and 60.0% at T1, T3, T5 and T8, respectively. In
the continuous CNi group, MetS disappeared in 41.7%, 46.7%, 28.6% and 0%, while it
disappeared in the mTORi switchers group in 42.9%, 12.5%, 12.5% and 25.0% of the patients
at T1, T3, T5 and T8, respectively. Within both groups, the component raised triglycerides
arose most often in patients who developed MetS. However, this proportion was substantially
higher in the mTORi switchers group. Within both groups the component reduced HDL
disappeared most often.
Conclusion: Liver transplant recipients who are switched to an mTORi seem to develop more
often MetS than patients who are continuously treated with a CNi. Furthermore, patients who
are continuously treated with a CNi seem to have a greater chance to recover from MetS. In
most cases, development of MetS seem to be caused by increased triglyceride levels, especially
in the mTORi switchers group. Independent of the immunosuppressant group, disappearance
of MetS seems to be most often the consequence of normalization of the HDL concentration. Continue reading






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Evaluatie poortwachtersrol van de huisarts in de huidkankerzorg : een retrospectieve dwarsdoorsnede studie






Introduction: The incidence of skin malignancies is increasing annually, amplifying the importance of primary care physicians role in diagnosing and treating dermatologic malignancies. It is estimated that 40% of skin lesions excised in primary care offices are not submitted for histopathological examination. Prior studies suggest that clinical diagnosis of primary care physicians is inaccurate, causing potential skin (pre-)malignancies to remain unrecognized. Furthermore, skin malignancies are more often radically excised by dermatologists than by primary care physicians. The role of the primary care physician is to recognize pre-malignancies as early as possible and then initiate an appropriate follow-up; either with a specialized care referral or treatment in the primary care office. In our opinion prior research lacks full information to draw conclusions on the clinical diagnosis of the primary care physician in skin malignancy care.
Study objective: To gain insight in the recognition of skin malignancies by primary care physicians and the effect of the clinical suspicion on the radicality of the cutting surfaces of the excised skin lesion. Methods: A retrospective cross-sectional study was performed; all skin excisions completed and sent in by primary care physicians in the catchment area of Isala during a 4 year timeframe were analysed. First, the histopathological diagnoses were grouped into either the benign or malignant category. The paired differential diagnosis and the general practitioner malignancy scale (1=definitely benign, 5=definitely malignant) were compared to the histopathological diagnoses. Second, the effect of a clinical suspicion of a (pre)malignancy or lack thereof on the percentage of radically excised skin malignancies was studied. Results: This study shows general practitioners predict a correct histopathological diagnosis based on the clinical suspicion in only 38.1%. However, when combining the differential diagnosis with the general practitioner malignancy scale, the general practitioners predict the correct histopathological nature of 78.9% of the (pre-)malignant lesions. Furthermore, this study showed that 1 in 22.7 skin excisions with no clinical suspicion for malignancy was diagnosed as a (pre)malignancy. One in every 200 skin lesions without any suspicion turned out to be a melanoma. The cutting surfaces of excised lesions were non-radical in 29.9%.The highest percentage, 43.2%, of non-radicality was found in the head-neck area.
Conclusion: Primary care physicians are quite capable of recognizing skin malignancies; however, 1 in 200 skin lesions with no clinical suspicion of malignancy turned out to be a melanoma. Therefore, to improve the accuracy of recognition, a guideline on “suspicious skin lesions” by the Dutch primary care physician society (Nederlands huisartsen genootschap, NHG) is necessary. Considering the high percentage of non-radical excisions of skin malignancies in the head-neck area, we advise primary care physicians to first take a biopsy of lesions in the head-neck area when there is a clinical suspicion of malignancy. When there is a histopathological diagnosed malignancy, we advise them to refer their patients to specialized care. Continue reading






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Het effect van neurolyse bij ramus infrapatellaris neuropathie






Objective: Entrapment neuropathy of the infrapatellar branch of the saphenous nerve is generally an unknown and unfrequently diagnosed cause of knee pain. The aim of this study was to evaluate the efficacy of surgery used by plastic surgeons to treat this neuropathy: neurolysis of the infrapatellar branch.
Methods: A cohort of patiënts diagnosed with infrapatellar neuropathy was evaluated. Patiënts that received treatment were asked their pain scores (Numeral Rating Scale 0-10) before and after surgery, their global perceived effect, and the influence of this disease on their life in terms of working and sporting. Patients treated with neurolysis between September 2014 and Februari 2015 were also evaluated prospectively. Their pain score was evaluated using the visual analog scale (10-100mm). In addition, neural conduction was measured before and after surgery using somatosensory evoked potentials (SSEP).
Results: A total of 55 patiënts with infrapatellar neuropathy were evaluated, of which 50 patiënts were treated by neurolysis. 74 percent of the treated patiënts (n = 32) demonstrated a numeral rating scale reduction of at least 50% in the first 6 months. On the long term, 96 percent (n = 48) showed a numeral rating scale reduction of on average 4 in 12 months after surgery. The reduction in pain score in treated patiënts differs significantly from that of untreated patients. Prospectively, 2 patiënt were evaluated. Both showed a visual analog scale reduction of at least 50% in 3 months after surgery. With the used SSEP technique described in literature no results could be reproduced that indicate neural conduction impairment.
Conclusion: Surgical neurolysis as a treatment for infrapatellar neuropathy is effective in about two-thirds of the patiënts. In addition, almost all patiënts (96%) will retrieve a significant reduction in pain in a 12 months recovery period. Continue reading






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A prospective cohort study on acute radiation-induced toxicity in the head andneck region : Development of normal tissue complication probability models.






Background: The purpose of this study was to identify which dose-volume parameters and
other pre-treatment factors can be used to predict most prevalent acute radiation-induced
toxicities, including xerostomia, dysphagia, mucositis, sticky saliva and loss of taste during
and immediately after radiation in the head and neck region.
Materials and methods: At the department of Radiation Oncology of the UMCG, a
retrospective analysis in a prospective cohort study was performed including 210 patients
with head and neck squamous cell carcinoma (HNSCC) treated with curative
(chemo)radiation. In all patients, acute radiation-induced toxicity was scored prospectively.
Univariable and multivariable logistic regression analysis were performed to develop
predictive models for grade ≥2 xerostomia, grade ≥4 dysphagia, grade ≥3 mucositis and grade
≥2 sticky saliva, scored at a weekly basis according to the CTCAEv4.0 international toxicity
scoring system to determine which dose-volume parameters were the most important
prognostic factors for the development of acute side effects.
Results: The multivariable logistic regression analyses revealed different prognostic factors:
the mean dose to the oral cavity for xerostomia, the mean dose to the pharyngeal constrictor
muscle for dysphagia, the mean dose to the oral cavity for mucositis and the mean dose to the
contralateral submandibular gland for sticky saliva.
Conclusion: A number of significant associations were found between the dose distribution in
certain organs-at-risk (OARs) and acute toxicity in HNSCC. However, for introduction into
routine clinical practice, further research with more advanced statistical methods to improve
the reliability of the models followed by external validation in an independent patient cohort
is needed. Continue reading






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The advantages of high-frame-rate videos in fiber endoscopic evaluation of swallowing.






Objectives: The purpose of this study was to verify whether or not high-frame-rate (HFR) videos were superior to standard-frame-rate (SFR) videos in the visual recognition of motion of the laryngopharyngeal structures during the pharyngeal phase of swallowing.
Method: Five healthy subjects were asked to swallow 0.5 ml water under fiberoptic transnasal laryngoscopy. The endoscope was connected to a high-speed digital imaging (HSDI) camera, which recorded the laryngopharyngeal view throughout the swallowing process at 4000 frames per second (fps). A total of five HFR videos were recorded, and were then copied and downsampled into a standard-frame-rate video version with 30 fps. Fifteen otorhinolaryngologists observed all ten HFR and SFR videos in random order, and rated the videos on a four-point rating scale reflecting the degree of the visual recognition of the rapid motions of the laryngopharyngeal structures just before the ‘white-out’ phenomenon.
Results: The number of observers judging the HFR videos with higher scores compared to the SFR videos was significantly higher for most laryngopharyngeal structures. These structures include: the posterior pharyngeal wall (p=0.001), the left lateral pharyngeal wall (p=0.015), the right lateral pharyngeal (p=0.035), the tongue base (p=0.005), and the epiglottis tilting (p=0.005). Only the recognition of laryngeal elevation (p=0.059) did not seem to benefit from a higher frame rate.
Conclusion: These results demonstrated the superiority of HFR videos compared to SFR videos in the evaluation of the contractive motions of the pharyngeal structures during the pharyngeal phase of swallowing. Continue reading






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Bone health in Zellweger spectrum disorders






Introduction: Zellweger spectrum disorders (ZSD) are a group of genetic metabolic disorders, caused by dysfunctional peroxisomes. Patients with a ZSD are often characterized by their heterogeneity in clinical presentation. Studies from the past decade… Continue reading






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A dose dependent relationship between periodontitis and hypercoagulability: the Periodontitis Increases Risk of AcuteThrombotic Events (PIRATE) study : (An unplanned interim analysis)






Introduction: Venous thrombo-embolism occurs in about 1:1000 people every year and can lead to disabling complications or in some cases, death. A substantial part of venous thrombo-embolism cases is still unexplained. The last decades, infection and inflammation are recognized as acquired risk factors for venous thrombosis. Periodontitis is a chronic inflammatory condition of the surrounding tissues of the teeth, that is relatively common in the population. In this observational study, we study the influence of periodontitis on coagulation values by measuring coagulation values before and after extraction of all teeth, so in presence and absence of severe periodontitis, in a patient population already eligible for this intervention. Methods: Patient recruitment took place at the department of oral and maxillofacial surgery of the University Medical Center of Groningen (UMCG). An unplanned interim analysis was performed using the 18 patients that already had completed the study. Severity of periodontitis was assessed directly before extraction of all teeth using PISA scores. Blood samples were obtained before intervention and three months thereafter. Thrombin Generation tests (with and without thrombomodulin) were performed using Calibrated Automated Thrombography (CAT). Furthermore, D-dimer (Hemosil HS 500) and Factor VIII were measured. Results:. In patients with PISA-scores > 2000 mm2, thrombin generation without thrombomodulin and D-dimer showed a significant decrease after intervention. Linear regression showed that the severity of periodontitis (PISA scores) had significant influence on the decline in coagulation values after intervention for thrombin generation without thrombomodulin and D-dimer. Factor VIII values were not influenced by periodontitis. Conclusion: A dose dependent relationship was observed between periodontitis severity and levels of D-dimer and thrombin generation without thrombomodulin. Thrombin generation with thrombomodulin was probably non-significant due to a lack of power. Only in very severe periodontitis patients, the influence of periodontitis on coagulation could possibly be clinical relevant, but more research has to be done. Continue reading






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The results of aortic valve repair procedures for aortic regurgitation






Background: Valve-preserving surgery of the aortic valve has become a standard approach in the treatment of aortic root aneurysm and aortic regurgitation (AR). By avoiding lifelong anticoagulation therapy it offers a good alternative for the composite graft replacement. Recently there is a renewed interest in this valve-preserving surgery, but due to limited experience with this procedure in the Netherlands, it is only performed in a small number of expertise centers.
Objectives: This study was performed to gain more data on valve-preserving surgery in one of these expertise centers in the Netherlands, the Thorax Centrum Twente (TCT) in Enschede. We studied the outcome of the aortic valve repair procedures looking at incidence of recurrent AR and valve-related complications, reduction of symptoms of AR and mortality rate. Outcome was compared with existing results of valve-preserving surgery.
Methods: Over a 4-year period, 69 consecutive patients underwent valve-preserving surgery in the TCT. In this retrospective cohort study, clinical and echocardiographic data were collected from medical records. Follow-up was complete in 100% (cumulative follow-up: 123 patient-years). Results: Overall freedom from relevant recurrent AR (≥ grade II) at 12, 24, 36 and 48 months after surgery was 92%, 87%, 83% and 66% respectively. Freedom from valve-related complications at 1 and 4 years after surgery was 91% and 89% respectively. There was a significant reduction in preoperative symptoms 3 months after the surgery (p Continue reading






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Invloed van feedback met behulp van 3D Gait op de voorspellende waarde voor blessures






AIM – A lot of recreational and competitive runners develop running related injuries. The aim of
this research is to improve the gait of the runners with the help of the 3D Gait system. At the
same time the improving of the gait will improve the injury index score, which is manufactured
by the 3D Gait software. DESIGN – pilot study. METHOD – 20 healthy people were examined
with the help of the 3D Gait system. All participants ran at each measurement at a speed of 9
km/h. They got markers on the feet, shank, thigh and pelvis. Before each measurement the
participants ran 4 minutes at a speed of 9 km/h to warm up, after that the measurement started.
After the first measurement feedback, generated with the help of the report made by the 3D Gait
software, was given to the participants. The parameters on which feedback was given were: Step
frequency, step width, pelvic drop, knee rotation, knee flexion and toe out angle. After the
feedback another 4 minutes of warming up was done and the second measurement was started.
After one month the 3 measurements took place at exactly the same way as the previous two
measurements. RESULTS – A significant improvement between the injury index measured at
measurement 1 and 2, but also a significant improvement between measurement 1 and 2 for the
secondary outcome, the hip, were found. Besides that, participants with running injuries in their
history made a significant higher score than the participants without running injuries in their
history. The feedback given at the hip made the score significantly improve between the three
measurements. CONCLUSION – This research shows that feedback with the help of 3D Gait the
injury index can be improved, but this improvement does not remain after 1 month. Continue reading






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