Smart hospital: achieving interoperability and raw data collection from medical devices in clinical routine

Introduction

Today, modern technology is used to diagnose and treat cardiovascular disease. These medical devices provide exact measures and raw data such as imaging data or biosignals. So far, the Broad Integration of These Health Data into Hospital Information Technology Structures-Especially in Germany-is Lacking, and if data integration takes place, only non-Evaluable Findings are Usually Integrated into the Hospital Information Technology Structures. A Comprehensive Integration of raw Data and Structured Medical Information has not yet Been Established. The aim of this project was to design and implement an interoperable database (cardio-vascular-information-system, CVIS) for the automated integration of al medical device data (parameters and raw data) in cardio-vascular medicine.

Methods

The CVIS serves as a data integration and preparation system at the interface between the various devices and the hospital IT infrastructure. In our project, we were able to establish a database with integration of proprietary device interfaces, which could be integrated into the electronic health record (EHR) with various HL7 and web interfaces.

Results

In the period between 1.7.2020 and 30.6.2022, the data integrated into this database were evaluated. During this time, 114,858 patients were automatically included in the database and medical data of 50,295 of them were entered. For technical examinations, more than 4.5 million readings (an average of 28.5 per examination) and 684,696 image data and raw signals (28,935 ECG files, 655,761 structured reports, 91,113 x-ray objects, 559,648 ultrasound objects in 54 different examination types, 5,000 endoscopy objects) were integrated into the database. Over 10.2 million bidirectional HL7 messages (approximately 14,000/day) were successfully processed. 98,458 documents were transferred to the central document management system, 55,154 materials (average 7.77 per order) were recorded and stored in the database, 21,196 diagnoses and 50,353 services/OPS were recorded and transferred. On average, 3.3 examinations per patient were recorded; in addition, there are an average of 13 laboratory examinations.

Discussion

Fully automated data integration from medical devices including the raw data is feasible and already creates a comprehensive database for multimodal modern analysis approaches in a short time. This is the basis for national and international projects by extracting research data using FHIR.

Exome-based gene panel analysis in a cohort of acute juvenile ischemic stroke patients:relevance of NOTCH3 and GLA variants

BACKGROUND

Genetic variants are considered to have a crucial impact on the occurrence of ischemic stroke. In clinical routine, the diagnostic value of next-generation sequencing (NGS) in the medical clarification of acute juvenile stroke has not been investigated so far.

MATERIAL AND METHODS

We analyzed an exome-based gene panel of 349 genes in 172 clinically well-characterized patients with magnetic resonance imaging (MRI)-proven, juvenile (age ≤ 55 years), ischemic stroke admitted to a single comprehensive stroke center.

RESULTS

Monogenetic diseases causing ischemic stroke were observed in five patients (2.9%): In three patients with lacunar stroke (1.7%), we identified pathogenic variants in NOTCH3 causing cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Hence, CADASIL was identified at a frequency of 12.5% in the lacunar stroke subgroup. Further, in two male patients (1.2%) suffering from lacunar and cardioembolic stroke, pathogenic variants in GLA causing Fabry's disease were present. Additionally, genetic variants in monogenetic diseases lacking impact on stroke occurrence, variants of unclear significance (VUS) in monogenetic diseases, and (cardiovascular-) risk genes in ischemic stroke were observed in a total of 15 patients (15.7%).

CONCLUSION

Genetic screening for Fabry's disease in cardioembolic and lacunar stroke as well as CADASIL in lacunar stroke might be beneficial in routine medical work-up of acute juvenile ischemic stroke.

High tumour mutational burden and EGFR/MAPK pathway activation are therapeutic targets in metastatic porocarcinoma

BACKGROUND

Eccrine porocarcinoma (EPC) is a rare skin cancer arising from the eccrine sweat glands. Due to the lack of effective therapies, metastasis is associated with a high mortality rate.

OBJECTIVES

To investigate the drivers of EPC progression.

METHODS

We carried out genomic and transcriptomic profiling of metastatic EPC (mEPC), validation of the observed alterations in an EPC patient-derived cell line, confirmation of relevant observations in a large patient cohort of 30 tumour tissues, and successful treatment of a patient with mEPC under the identified treatment regimens.

RESULTS

mEPC was characterized by a high tumour mutational burden (TMB) with an ultraviolet signature, widespread copy number alterations and gene expression changes that affected cancer-relevant cellular processes such as cell cycle regulation and proliferation, including a pathogenic TP53 (tumour protein 53) mutation, a copy number deletion in the CDKN2A (cyclin dependent kinase inhibitor 2A) region and a CTNND1/PAK1 [catenin delta 1/p21 (RAC1) activated kinase 1] gene fusion. The overexpression of EGFR (epidermal growth factor receptor), PAK1 and MAP2K1 (mitogen-activated protein kinase kinase 1; also known as MEK1) genes translated into strong protein expression and respective pathway activation in the tumour tissue. Furthermore, a patient-derived cell line was sensitive to EGFR and MEK inhibition, confirming the functional relevance of the pathway activation. Immunohistochemistry analyses in a large patient cohort showed the relevance of the observed changes to the pathogenesis of EPC. Our results indicate that mEPC should respond to immune or kinase inhibitor therapy. Indeed, the advanced disease of our index patient was controlled by EGFR-directed therapy and immune checkpoint inhibition for more than 2 years.

CONCLUSIONS

Molecular profiling demonstrated high TMB and EGFR/MAPK pathway activation to be novel therapeutic targets in mEPC.

A versatile liquid-jet setup for the European XFEL

The SPB/SFX instrument of the European XFEL provides unique possibilities for high-throughput serial femtosecond crystallography. This publication presents the liquid-jet sample delivery setup of this instrument. The setup is compatible with state-of-the-art gas dynamic virtual nozzle systems as well as high-viscosity extruders and provides space and flexibility for other liquid injection devices and future upgrades. The liquid jets are confined in a differentially pumped catcher assembly and can be replaced within a couple of minutes through a load-lock. A two-microscope imaging system allows visual control of the jets from two perspectives.

Sequence-dependent cross-resistance of combined radiotherapy plus BRAFV600E inhibition in melanoma

INTRODUCTION

Treatment of patients with metastatic melanoma is hampered by drug-resistance and often requires combination with radiotherapy as last-resort option. However, also after radiotherapy, clinical relapses are common.

METHODS & RESULTS

Our preclinical models indicated a higher rate of tumour relapse when melanoma cells were first treated with BRAF^V600E inhibition (BRAFi) followed by radiotherapy as compared to the reverse sequence. Accordingly, retrospective follow-up data from 65 stage-IV melanoma patients with irradiated melanoma brain metastases confirmed a shortened duration of local response of mitogen-activated protein kinase (MAPK)-inhibitor-pretreated compared with MAPK-inhibitor-naïve intracranial metastases. On the molecular level, we identified JARID1B/KDM5B as a cellular marker for cross-resistance between BRAFi and radiotherapy. JARID1B^high cells appeared more frequently under upfront BRAFi as compared with upfront radiation. JARID1B favours cell survival by transcriptional regulation of genes controlling cell cycle, DNA repair and cell death.

CONCLUSION

The level of cross-resistance between combined MAPK inhibition and radiotherapy is dependent on the treatment sequence. JARID1B may represent a novel therapy-overarching resistance marker.

Gene expression profiling in aggressive digital papillary adenocarcinoma sheds light on the architecture of a rare sweat gland carcinoma

BACKGROUND

Sweat gland carcinomas are rare cutaneous adnexal malignancies. Aggressive digital papillary adenocarcinoma (ADPA) represents a very rare subentity, thought to arise almost exclusively from the sweat glands of the fingers and toes. The aetiology of sweat gland carcinomas and ADPA is largely unknown. ADPAs are most likely driven by somatic mutations. However, somatic mutation patterns are largely unexplored, creating barriers to the development of effective therapeutic approaches to the treatment of ADPA.

OBJECTIVES

To investigate the transcriptome profile of ADPA using a sample of eight formalin-fixed, paraffin-embedded tissue samples of ADPA and healthy control tissue.

METHODS

Transcriptome profiling was performed using the Affymetrix PrimeView Human Gene Expression Microarray and findings were validated via reverse transcription of RNA and real-time quantitative polymerase chain reaction.

RESULTS

Transcriptome analyses showed increased tumour expression of 2266 genes, with significant involvement of cell cycle, ribosomal and crucial cancer pathways. Our results point to tumour overexpression of FGFR2 (P = 0·001).

CONCLUSIONS

The results indicate the involvement of crucial oncogenic driver pathways, highlighting cell cycle and ribosomal pathways in the aetiology of ADPA. Suggested tumour overexpression of FGFR2 raises the hope that targeting the fibroblast growth factor (FGF)/FGF receptor axis might be a promising treatment for ADPA and probably for the overall group of sweat gland carcinomas.

Platelet Function and Hemolysis in Centrifugal Pumps: In Vitro Investigations

The effects of centrifugal pumps on blood components other than erythrocytes, namely platelets and their interaction with the coagulation system, are not very well known. In a comparative study with three centrifugal pumps (BioMedicus BP-80, St. Jude Isoflow, and Sarns Delphin) and the Stöckert roller pump hemolysis, platelet counts, thromboplastin and partial thromboplastin times, as well as resonance thrombography (RTG) parameters for the assessment of platelet and coagulation function were evaluated in vitro. Normalized indices of hemolysis (NIH) with ACD anticoagulation after 360 minutes were 0.008 ± 0.004 (Isoflow), 0.018 ± 0.017 (BP-80), 0.085 ± 0.051 (Delphin), and 0.049 ± 0.010 g/1001 (roller pump). Plasmatic coagulation was activated in all circuits. Platelet function was severely inhibited by the BP-80, indicated by increase in RTG platelet time to 358% ± 150% of initial values compared to 42% ± 29% (Isoflow), 40% ± 20% (Delphin), and 12% ± 10% (roller pump). Fibrin polymerization was affected similarly. The large surface area of the BP-80 leads to an extensive activation of platelets and plasminogen.

Bak apoptotic pores involve a flexible C-terminal region and juxtaposition of the C-terminal transmembrane domains

Bak and Bax mediate apoptotic cell death by oligomerizing and forming a pore in the mitochondrial outer membrane. Both proteins anchor to the outer membrane via a C-terminal transmembrane domain, although its topology within the apoptotic pore is not known. Cysteine-scanning mutagenesis and hydrophilic labeling confirmed that in healthy mitochondria the Bak α9 segment traverses the outer membrane, with 11 central residues shielded from labeling. After pore formation those residues remained shielded, indicating that α9 does not line a pore. Bak (and Bax) activation allowed linkage of α9 to neighboring α9 segments, identifying an α9:α9 interface in Bak (and Bax) oligomers. Although the linkage pattern along α9 indicated a preferred packing surface, there was no evidence of a dimerization motif. Rather, the interface was invoked in part by Bak conformation change and in part by BH3:groove dimerization. The α9:α9 interaction may constitute a secondary interface in Bak oligomers, as it could link BH3:groove dimers to high-order oligomers. Moreover, as high-order oligomers were generated when α9:α9 linkage in the membrane was combined with α6:α6 linkage on the membrane surface, the α6-α9 region in oligomerized Bak is flexible. These findings provide the first view of Bak carboxy terminus (C terminus) membrane topology within the apoptotic pore.

Platelet function and hemolysis in centrifugal pumps: in vitro investigations

The effects of centrifugal pumps on blood components other than erythrocytes, namely platelets and their interaction with the coagulation system, are not very well known. In a comparative study with three centrifugal pumps (BioMedicus BP-80, St. Jude Isoflow, and Sarns Delphin) and the Stockert roller pump hemolysis, platelet counts, thromboplastin and partial thromboplastin times, as well as resonance thrombography (RTG) parameters for the assessment of platelet and coagulation function were evaluated in vitro. Normalized indices of hemolysis (NIH) with ACD anticoagulation after 360 minutes were 0.008+/-0.004 (Isoflow), 0.018+/-0.017 (BP-80), 0.085+/-0.051 (Delphin), and 0.049+/-0.010 g/1001 (roller pump). Plasmatic coagulation was activated in all circuits. Platelet function was severely inhibited by the BP-80, indicated by increase in RTG platelet time to 358%+/-150% of initial values compared to 42%+/-29% (Isoflow), 40%+/-20% (Delphin), and 12%+/-10% (roller pump). Fibrin polymerization was affected similarly. The large surface area of the BP-80 leads to an extensive activation of platelets and plasminogen.

The implementation of a quality-net as a part of the European project DIABCARE Q-Net

DIABCARE Q-Net is a European project with a consortium of partners in healthcare, industry, and research, which has the overall target of improvement in diabetes care by aggregation, evaluation, and feedback of anonymized patient data with the tools of modern telematics, resulting from the initiative of the St. Vincent-Declaration, St. Vincent, Italy. Based on standardized tools for quality improvement in diabetes care, i.e., the Basic Information Sheet (BIS) and recently developed data entry and feedback software (DIABCARE Data for Windows), DIABCARE Q-Net as a part of the Telematics Applications Program of the European Commission will improve diabetes care and disease management by the implementation of a quality network. Therefore, the project implements regional, national, and central nodes for processing of diabetes quality indicators. All participating centers (GP's and clinics in Europe) get feedback by standardized benchmarking. The pilot testing and the state of implementation of our network confirm the importance of improving the quality of life of diabetic patients in all participating countries.

Acute inhalation toxicity testing: considerations of technical and regulatory aspects

The EU regulatory statute for the acute hazard identification of chemicals requires selection of the two most appropriate routes of administration. Testing employing the oral route is mandatory, whereas selection of the dermal or inhalation route requires expert judgement, i.e. considerations of structural alerts with regard to the inherent acute inhalation toxicity as well as the likelihood of dermal and inhalation exposure, respectively. Currently, testing of chemicals requires acute inhalation exposure of 4-h and 1-h durations according the EU classification and labelling and UN Transport Guidelines, respectively. The analysis made revealed that 1-h exposures appear to add little knowledge in addition to existing 4-h LC50 values and a default value of 4 should be used for conversion of 4-h to 1-h LC50 values, independently of the physical state of the chemical. Therefore, also the unit of concentration of exposure atmospheres should be independent of nominal features of the test substance. Hence, the preferred dose metric is mass (mg/liter air) rather than volume (ppm). Taking into account the overall variability of acute toxicity data the recommendations given are classification into the following groups of 4-h LC50 values: < or = 0.05, > 0.05-0.2, > 0.2-1, > 1-5 and > 5.0 mg/l. No distinction should be made concerning vapours and aerosols with regard to units and conversion factors from 4-h to 1-h LC50 values and the default factor of 4 appears to be most suitable. Further differentiation of classification is not indicated due to technical variability of acute inhalation testing and resolution of the acute bioassay.

Incorporation of oleic acid and eicosapentaenoic acid into glycerolipids of cultured normal human fibroblasts

Confluent skin fibroblasts from normal humans were incubated in serum free medium with up to 100 nmole/mL eicosapentaenoic acid (EPA; bound to albumin in a 4.6:1 ratio) and compared with cells incubated with oleic acid (OA) at similar concentrations. The rate of [14C]OA incorporation into triacylglycerol (TG) (nmol/mg/h) was approximately 5-fold greater than that of [14C]EPA. The mass of TG formed after incubation of fibroblasts with EPA was also significantly lower than that formed with OA (43.2 +/- 9.3 vs. 59.5 +/- 6.6 micrograms/mg cell protein, respectively, P = 0.006). The addition of excess, unlabeled EPA reduced the rate of incorporation of [14C]OA into TG whereas unlabeled OA stimulated incorporation of [14C]EPA into TG. When the cells were preincubated with human serum basic proteins (BP I, II and III), the mass of TG formed (compared to baseline) was significantly higher with the basic proteins whether OA or EPA was studied. Only BP I significantly stimulated the mass of cell phospholipids, an effect that occurred with either OA or EPA in the medium. The results suggest that in cultured normal human fibroblasts, OA is a better substrate for TG synthesis than EPA and that this effect may be accentuated by the presence of the basis proteins.

Two-dimensional color-mapping of turbulent shear stress distribution downstream of two aortic bioprosthetic valves in vitro

Since artificial heart valve related complications such as thrombus formation, hemolysis and calcification are considered related to flow disturbances caused by the inserted valve, a thorough hemodynamic characterization of heart valve prostheses is essential. In a pulsatile flow model, fluid velocities were measured one diameter downstream of a Hancock Porcine (HAPO) and a Ionescu-Shiley Pericardial Standard (ISPS) aortic valve. Hot-film anemometry (HFA) was used for velocity measurements at 41 points in the cross-sectional area of the ascending aorta. Three-dimensional visualization of the velocity profiles, at 100 different instants during one mean pump cycle, was performed. Turbulence analysis was performed as a function of time by calculating the axial turbulence energy within 50 ms overlapping time windows during the systole. The turbulent shear stresses were estimated by using the correlation equation between Reynolds normal stress and turbulent (Reynolds) shear stress. The turbulent shear stress distribution was visualized by two-dimensional color-mapping at different instants during one mean pump cycle. Based on the velocity profiles and the turbulent shear stress distribution, a relative blood damage index (RBDI) was calculated. It has the feature of combining the magnitude and exposure time of the estimated shear stresses in one index, covering the entire cross-sectional area. The HAPO valve showed a skewed jet-type velocity profile with the highest velocities towards the left posterior aortic wall. The ISPS valve revealed a more parabolic-shaped velocity profile during systole. The turbulent shear stresses were highest in areas of high or rapidly changing velocity gradients. For the HAPO valve the maximum estimated turbulent shear stress was 194 N m-2 and for the ISPS valve 154 Nm-2. The RBDI was the same for the two valves. The turbulent shear stresses had magnitudes and exposure times that might cause endothelial damage and sublethal or lethal damage to blood corpuscules. The RBDI makes comparison between different heart valves easier and may prove important when making correlation with clinical observations.

Comparison of conductivity measured hematocrit to microhematocrit

Two electrical conductivity methods of hematocrit (H) measurement, Coulter Counter (CCH) and lonometer (IH), were compared to the microhematocrit (MH) with two different anticoagulants, Li Heparin (Li) and EDTA. The results showed MH-Li is higher than MH-EDTA (mean difference 1.7 vol%). The IH-Li is 1.8 vol% higher than CC H-EDTA. These differences are attributed to osmotic shrinking of red cells by EDTA. The MH-Li and IH-Li correlate very closely (r = .992), and are considered to provide the truest hematocrit values.

Estimation of turbulent shear stresses in pulsatile flow immediately downstream of two artificial aortic valves in vitro

Measuring turbulent shear stresses is of major importance in artificial heart valve evaluation. Bi- and unidirectional fluid velocity measurements enable calculation of Reynolds shear stress [formula: see text] and Reynolds normal stress [formula: see text]. tau is important due to the relation to hemolysis and thrombus formation, but sigma is the only obtainable parameter in vivo. Therefore, determination of a correlation factor between tau and sigma is pertinent. In a pulsatile flow model, laser Doppler (LDA) and hot-film (HFA) anemometry were used for simultaneous bi- and unidirectional fluid velocity measurements downstream of a Hall Kaster and a Hancock Porcine aortic valve. Velocities were registered in two flow field locations and at four cardiac outputs. The velocity signals were subjected to analog signal processing prior to digital turbulence analysis, as a basis for calculation of tau and sigma. A correlation factor of 0.5 with a correlation coefficient of 0.97 was found between the maximum Reynolds shear stress and Reynolds normal stress, implying [formula: see text]. In vitro estimation of turbulent shear stresses downstream of artificial aortic valves, based on the axial velocity component alone, seems possible.

Three-dimensional visualization of axial velocity profiles downstream of six different mechanical aortic valve prostheses, measured with a hot-film anemometer in a steady state flow model

Hot-film anemometry was used for in vitro steady-state measurements downstream of six mechanical aortic valve prostheses at flow rates 10, 20 and 30 l.min-1. Three-dimensional visualizations of velocity profiles at two downstream levels were made with the valves rotated 0 and 60 degrees in relation to the sinuses of valsalvae. The velocity fields downstream of the disc valves were generally skew with increasing velocity gradients and laminar shear stresses with increasing flow rates. Furthermore, increased skewness of the velocity profiles was noticed when the major orifices of the disc valves were towards the commissure than when approaching a sinus of valsalvae. The velocity profiles downstream of the ball valve were generally flat but with considerably more disturbed flow, consistent with the findings in turbulent flow.

Biotransformation von monolinuron (N-(4-chlorphenyl)-N′-methyl-N′-methoxyharnstoff) in der isoliert perfundierten Hühnerleber

The biotransformation of radioactively labelled monolinuron (N-(4-chloro[U-14C]phenyl)-N'-methyl-N'-methoxyurea) was studied in the isolated perfused liver of the chicken. After a 4-hr perfusion, 83.1% of the added radioactivity was recovered, 56.6% in the perfusion medium and 26.5% in the liver and bile. The fraction of radioactivity extractable from the perfusion medium into ethyl acetate amounted to 47.8% of the added dose. In addition to monolinuron, five breakdown products were identified in this extract, namely N-(4-chlorophenyl)-N'-hydroxymethyl-N'-methoxyurea, N-(4-chlorophenyl)-N'-methoxyurea, N-(4-chlorophenyl)-N'-methylurea, 4-chlorophenylurea and 4-chloroacetanilide. Of particular interest was the absence of arylhydroxylated monolinuron derivatives, since in monolinuron-metabolism studies in the laying hen 2-hydroxy-4-chlorophenylurea and 3-hydroxy-4-chlorophenylurea were both detected. This differing metabolism corresponds to earlier findings in the rat, in which arylhydroxylated breakdown products were detected only in in vivo studies and not in rat-liver perfusion. Possible reasons for the differing metabolism of monolinuron in vivo and in vitro are discussed.

[Gas chromatographic analysis in the detection of anaerobes]

By means of gaschromatography a rapid (ca 30 min) diagnosis of anaerobic infections is possible. The principle of a simple technique regarding the equipment and the laboratory-chemical process is presented.

[Bulbus motility in early and late surgery of orbital floor fractures (author's transl)]

Among 638 patients with fractures of the middle third of the facial skeleton 139 were found to have clinically relevant fractures of the orbital floor. 74 of them were followed up ophthalmologically and by x-ray examination. In 49 patients the results of the operative treatment were judged from a detailed questionnaire. Operation within 2 weeks after the accident yielded better results than later operation. Persisting motility disturbances concerned mainly the upper field of gaze.

[Delayed infections after foreign body inclusion in the maxillofacial region]

Nine cases of so-called late infections following foreign body inclusions due to trauma as well as possible developmental mechanisms were discussed. The question arises as to whether a nonirritating incorporated foreign body should be surgically removed as early as possible to eliminate the possibility of late infection.

Hypoxemia following the administration of sublingual nitroglycerin

Nitroglycerin, 0.6 mg sublingually, was given to 27 nonasthmatic subjects with varying degrees of airways dysfunction to determine the effect on arterial oxygenation. In six normal subjects, the partial pressure of oxygen in arterial blood (Pao2) transiently decreased by 9 mm Hg (p less than 0.05) and in eight subjects with only small airways dysfunction, the Pa02 decreased by 14 mm Hg (p less than 0.0001). The alveolar-arterial oxygen gradient on oxygen increased by only 11 mm Hg indicating that the decrease in room air Pao2 was primarily due to worsening ventilation-perfusion mismatch and not to an increase in shunt. Thirteen subjects with advanced obstructive or restrictive lung disease experienced a much lesser decrease in Pao2 of 4 mm Hg. Data are presented on xenon perfusion studies of a dog model of unilateral alveolar hypoxia that suggest the worsening ventilation-perfusion ratio seen in the human subjects after the administration of nitroglycerin could be due to loss of the lung's ability to vasoconstrict in regions of alveolar hypoxia and shift perfusion to better ventilated regions of the lung.

[Infected dermoid and epidermoid cysts in the maxillofacial region. Differential diagnosis and therapy]

More than 30% of the patients with dermoid and epidermoid cysts treated on an in-patient basis during the last 10 years in the Düsseldorf Hospital for Jaw and Plastic Surgery showed symptoms of acute or chronic inflammation. The difficulties involved in the clinical diagnosis of infected dermoid or epidermoid cysts were illustrated by example cases. Infected dermoid and epidermoid cysts may be mistaken for ondontogenous abscesses, infected atheromas, furuncles, superinfected tumors, and specific inflammations.

[Infected median and lateral neck cysts and fistulas]

During the last 10 years, 50 patients with congenital anomalies of the neck were treated in the Hospital for Oral and Plastic Surgery in Düsseldorf. Acute or chronic infection was observed in one third of the median and lateral cervical cysts and all cervical fistulas. Most of the cysts and fistulas were not diagnosed or considered in the differential diagnosis at the time of referral. The most frequent false diagnoses were: odontogenous abcess, odontogenous fistula, phlegmon of the floor of the mouth, specific lymphoma, abcess of the lymph node.

Testing in vitro of an indirect mutagen (cyclophosphamide) with human leukocyte cultures: Activation by liver perfusion and by incubation with crude liver homogenate

The indirect mutagen cyclophosphamide was tested in human whole blood cultures with respect to chromosome-breaking activities and suppression of mitotic indices after activation by liver perfusion and crude liver homogenates with and without cofactors. Both methods produced nearly the same effects, with the exception of liver homogenate without cofactors which had only weak metabolic activities.

Sinuscopy for the diagnosis of blow-out fractures

Between 1973 and 1976 thirty-one patients with the symptoms of a blow-out fracture underwent sinuscopy. In all these cases a precise diagnosis was not possible from the clinical and x-ray findings alone without exploratory surgery. In 28 cases an exact diagnosis could be made using sinuscopy; 21 patients with blow-out fractures underwent reconstructive surgery to the orbital floor. In the remaining 7 cases fracture of the orbital floor was ruled out and the patients were spared more extensive diagnostic procedures. In 3 cases the diagnosis of a fracture could not be definitely established. Exploratory surgery of the orbital floor showed blow-out fractures which needed treatment. These findings were photographed; 5 typical photographs of fractures are presented. Sinuscopy provides a simple and sure method in the diagnosis of blow-out fractures. Its early application is recommended in cases of suspected fractures of the orbital floor, since reconstructive surgery of blow-out fractures yields the best functional results when performed within 2 weeks after the accident.