Small dense LDL cholesterol in human subjects with different chronic inflammatory diseases

BACKGROUND AND AIMS

Chronic inflammatory diseases (CID) are associated with a profound increase in cardiovascular (CV) risk resulting in reduced life expectancy. However, LDL-cholesterol is reported to be low in CID patients which is referred to as the "LDL paradoxon". The aim of the present study was to investigate whether LDL-particles in CID exhibit an increased content of the highly atherogenic small-dense LDL subfraction (sdLDL).

METHODS AND RESULTS

In this prospective, single center, observational study we enrolled 141 patients with CID (RA n = 59, inflammatory bowel disease (IBD) n = 35, ankylosing spondylitis (SpA) n = 25, Psoriasis n = 22) in 2011 through 2013 to evaluate sdLDL levels before as well as 6 and 26 weeks after initiation of different anti-cytokine therapies (anti-TNFα, anti-IL-6R antibodies). sdLDL levels were compared to 141 healthy individuals in a case control design. Compared to healthy controls, all CID patients displayed a significantly higher sdLDL content within the LDL cholesterol fraction: RA 35.0 ± 9.2% (p < 0.001), SpA 42.5 ± 10.5% (p < 0.001), IBD 37.5 ± 7.1% (p < 0.001), Psoriasis 33.6 ± 4.6% (p < 0.01). Furthermore, the sdLDL/LDL ratio was significantly higher in male compared to female RA subjects (p < 0.05). Neither anti-TNFα nor anti-IL6R medication altered sdLDL levels despite a significant improvement of disease activity.

CONCLUSION

In several different chronic inflammatory disease entities, LDL-cholesterol is shifted toward a pro-atherogenic phenotype due to an increased sdLDL content which might in part explain the LDL paradoxon. Since premature CV disease is a major burden of affected patients, specifically targeting lipid metabolism should be considered routinely in clinical patient care.

CLINICAL TRIALS

Registration at German Clinical Trial Register (DRKS): DRKS00005285.

OT2-05-02: ACRIN 6691 Monitoring and Predicting Breast Cancer Neoadjuvant Chemotherapy Response Using Diffuse Optical Spectroscopic Imaging (DOSI)

Background

Imaging technologies monitoring and predicting breast cancer response to neoadjuvant chemotherapy (NAC) are of increasing interest. The utility of conventional imaging approaches varies and identifies the need for alternate functional imaging strategies. The use of model-based photon migration methods to quantitatively separate light absorption from scattering in multiply-scattering tissues is a type of near-infrared spectroscopy (NIRS) broadly referred to as diffuse optical spectroscopy (DOS) [Bevilacqua, et al. Applied Optics, 2000; Jakubowski, et al., J of Applied Optics, 2009]. DOSI is a promising experimental technology that allows patients undergoing NAC to be followed with a “no significant risk” device meeting Food and Drug Administration criteria for exempt status. The current design is a mobile device which offers increased accessibility and is relatively simple to perform and interpret, as compared to mammography, magnetic resonance imaging, and positron emission tomography. Due to its size and portability, DOSI is a low barrier-to-access technology, creating new opportunities for patients to receive personalized treatment and for physicians to gain new insight into response mechanisms. The long-term goal is to provide oncologists with a relatively simple, risk-free bedside tool that can be used to help inform medical decisions on chemotherapy regimen, duration, and timing of surgery, thereby maximizing therapeutic response and minimizing unnecessary toxicity.

Trial design: In this phase I/II prospective single arm study, patients will receive SOC NAC at five (5) NCI Network for Translational Research in Optical Imaging (NTROI) clinical sites with identical DOSI instruments and procedures. Patients will receive four DOSI exams: at baseline before chemotherapy, at early therapy 5–10 days after NAC initiation, at mid therapy, and at post therapy prior to surgery. The protocol will evaluate a harmonized DOSI technology platform that has been standardized for NAC monitoring.

Eligibility: Women who have been diagnosed with breast cancer, have had confirmation by pre-treatment biopsy, and are scheduled to receive NAC followed by surgery are eligible for this trial.

Specific aims: The primary aim of this clinical trial is to determine whether the baseline to mid-therapy changes in the DOSI measurement of the quantitative tumor tissue optical index can predict final pathologic complete response in patients with breast cancer undergoing NAC. The secondary aims investigate the correlation between additional DOSI quantitative measurements of tumor biochemical composition obtained at other timepoints, the full range of pathologic response (i.e. complete, partial, and non-response), and any corresponding imaging measurements.

Statistical methods: Logistic regression models will be used to study the relationships between pathological complete response and percent change in tissue optical index tumor to normal ratio at different imaging time points.

Study size: A total of sixty (60) patients will be enrolled in this imaging study. Currently, one patient has accrued.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT2-05-02.

Sensitivity study of an ultrasound coupled transrectal electrical impedance tomography system for prostate imaging

In 2009, prostate cancer ranked as the most common cancer and the second most fatal cancer in men in the United States. Unfortunately, the current clinical diagnostic methods (e.g. prostate-specific antigen (PSA), digital rectal examination, endorectal MRI, transrectal ultrasound, biopsy) used for detecting and staging prostate cancer are limited. It has been shown that cancerous prostate tissue has significantly different electrical properties when compared to benign tissues. Based on these electrical property findings, a transrectal electrical impedance tomography (TREIT) system is proposed as a novel prostate imaging modality. The TREIT system comprises an array of electrodes interfaced with a clinical transrectal ultrasound (TRUS) probe. We evaluate this imaging system through a series of phantom imaging experiments to assess the system's ability to image high and low contrast objects at various positions. We found that the TREIT system can easily discern high contrast inclusions of 1 cm in diameter at distances centered at two times the radius of the TREIT probe away from the probe surface. Furthermore, this technology's ability to detect low contrast inclusions suggests that it has the potential to successfully detect prostate cancer.

Chemotherapy-induced nausea, vomiting, and fatigue--the role of individual differences related to sensory perception and autonomic reactivity

BACKGROUND

In spite of antiemetics, postchemotherapy side effects continue to be common and may affect compliance to cancer treatment. Among the known factors associated with increased symptom severity are: younger age, treatment toxicity, expected severity, and distress, but little is still known about the role of other factors. The aim of our study was to investigate the role of individual differences related to sensory perception for posttreatment side effects.

METHODS

Hundred and twenty-five women receiving adjuvant chemotherapy for breast cancer completed measures of absorption, autonomic perception, somatosensory amplification, trait anxiety, and expected severity at baseline. Pretreatment distress and posttreatment nausea, vomiting, and fatigue were assessed at the 1st, 4th, 6th and last cycles of chemotherapy.

RESULTS

While univariate analyses showed several factors to be associated with side effects, only absorption and pretreatment distress remained independent predictors of nausea and fatigue when controlling for the remaining factors. Posttreatment vomiting was only predicted by expected severity of vomiting.

CONCLUSION

Chemotherapy-induced side effects are related to increased autonomic nervous system activity, and absorption has been associated with increased autonomic nervous system reactivity to stress. The results suggest that individuals with high absorption may be at greater risk for developing side effects. Improved precision in identifying patients at risk of experiencing more severe side effects after cancer treatment will increase the ability to target treatments aimed at reducing these side effects.

Multimodal image re-registration via mutual information to account for initial tissue motion during image-guided neurosurgery

Multimodal imaging modalities, such as high-resolution pre-operative MR (pMR) and intra-operative US (iUS), have been used widely to provide complementary information for guiding neurosurgery. Proper registration between the images is usually established fiducials placed on the patient skull, which can be identified both in MR and a tracking system that also records location and orientation of each iUS scan. Although such systems can achieve high registration accuracy, we have observed brain tissue motion with respect to the skull after the craniotomy and before opening of the dura. We developed a rigid registration strategy to re-align the brain in iUS and pMR to account for such motion. The mutual information between the two modalities is maximized through a genetic algorithm. Two patient cases are presented to show the improved registration accuracy of soft tissues.

Anticipatory Nausea: The Role of Individual Differences Related to Sensory Perception and Autonomic Reactivity

BACKGROUND

Anticipatory nausea (AN) during chemotherapy has been difficult to control with conventional antiemetics. AN can lead cancer patients to delay or discontinue chemotherapy, possibly compromising the treatment.

PURPOSE

The aim is to investigate the possible influence on the development of AN of individual differences in absorption, somato-sensory amplification, and autonomic perception-measures theorized to be related to sensory perception and autonomic reactivity.

METHODS

Prior to treatment, 125 women (M age = 48.5 years) undergoing adjuvant chemotherapy for breast cancer rated their expected severity of side effects and completed the Tellegen Absorption Scale, the Somato-Sensory Amplification Scale, and the Autonomic Perception Questionnaire. AN, as well as anticipatory vomiting (AV), distress, and worry/anxiety, were measured prior to the fourth, sixth, and last cycle of chemotherapy. Posttreatment nausea (PN), vomiting, and fatigue were measured after the first, fourth, sixth, and last cycle.

RESULTS

34% of the women reported AN before 1 or more cycles. When controlling for treatment characteristics and other known predictors, AN was significantly associated with high absorption in addition to severity of PN, pretreatment worry/anxiety, and not receiving radiotherapy between chemotherapy sessions. AV was not associated with any of the variables investigated. Our data suggest that the association is strongest in the early phases of treatment.

CONCLUSIONS

Our results partly confirm the results of a previous study showing absorption and autonomic perception as predictors of anticipatory side effects in cancer patients receiving chemotherapy. Individuals high in absorption may be more autonomically reactive to aversive stimuli and, subsequently, more conditionable. Additional radiotherapy could be a competing stimulus, reducing the conditioning of chemotherapy-related nausea. Further studies investigating possible psycho-physiological mechanisms in the development of AN are needed.

Intra-operative image updating

Intraoperative brain shift and deformation pose challenges for image-guided surgery. One strategy to address these problems utilizes computational modeling coupled with intraoperatively acquired information from efficient and economical sources such as ultrasound and the optics of the operating microscope. Calibration algorithms for the accurate integration of these sparse data sources have been implemented. Assessment has been performed in both phantom and pig brain models, and accuracy better than 2 mm has been achieved. Methods of incorporating these data into the computational model are being developed.

Comparison of imaging geometries for diffuse optical tomography of tissue

Images produced in six different geometries with diffuse optical tomography simulations of tissue have been compared using a finite element-based algorithm with iterative refinement provided by the Newton-Raphson approach. The source-detector arrangements studied include (i) fan-beam tomography, (ii) full reflectance and transmittance tomography, as well as (iii) sub-surface imaging, where each of these three were examined in a circular and a flat slab geometry. The algorithm can provide quantitatively accurate results for all of the tomographic geometries investigated under certain circumstances. For example, quantitatively accurate results occur with sub-surface imaging only when the object to be imaged is fully contained within the diffuse projections. In general the diffuse projections must sample all regions around the target to be characterized in order for the algorithm to recover quantitatively accurate results. Not only is it important to sample the whole space, but maximal angular sampling is required for optimal image reconstruction. Geometries which do not maximize the possible sampling angles cause more noise artifact in the reconstructed images. Preliminary simulations using a mesh of the human brain confirm that optimal images are produced from circularly symmetric source-detector distributions, but that quantitatively accurate images can be reconstructed even with a sub-surface imaging, although spatial resolution is modest.

Sampling of time- and frequency-domain signals in monte carlo simulations of photon migration

We compare two fundamentally different ways to evaluate the time dependence in Monte Carlo simulations of photon migration: estimating the pulse response in time versus evaluating the transfer function at discrete points in the frequency domain. We show that these two methods differ in accuracy owing to quantization and sampling errors, whereas the statistical error is essentially the same for both methods. From our analysis we also derive alternative methods to sample the time-domain pulse response with reduced quantization and sampling error. Simulation results are included to illustrate our theoretical analysis.

Non-invasive thermal assessment of tissue phantoms using an active near field microwave imaging technique

An active microwave imaging system for non-invasive temperature sensing has been developed and evaluated. The system is designed to assess biological tissues undergoing thermal therapy. This paper presents results that demonstrate the imaging capabilities of the microwave method using simulated and experimental phantom materials. Results from both numerical studies and laboratory experiments have been analysed and are presented. The imaging system uses a 16 channel fixed monopole array transceiver unit operating over a bandwidth of 300-900 MHz. The annular array diameter is 14.75 cm and is immersed in a 0.9% saline solution. Standard heterodyning principles are used for signal detection leading to a dynamic range of the system of better than 115dB. Image formation is accomplished with a 2-D finite element based, near-field iterative technique. This allows the simultaneous reconstruction of both the real and imaginary components of the dielectric property distribution in tissue equivalent phantoms. Data acquisition currently captures 144 complex field measurements per image. Image reconstruction requires approximately 2 min per iteration with a typical convergence in less than 10 steps. Experiments performed to evaluate the temperature dependence of biological phantoms (saline with variable salt concentrations) are described. The numerical accuracy and precision of the reconstruction algorithm based upon these phantom studies are presented. Simple laboratory models of localized hyperthermia have been used to evaluate the experimental accuracy and precision of the imaging system. A numerical precision of 0.02 degrees C and an accuracy of 0.37 degrees C have been observed with the current algorithm. In laboratory experiments, images have been reconstructed at different target temperatures and target saline concentrations. The effect of placing high contrast biological phantoms (i.e. bone/fat simulants) along with the heated objects have also been studied. Localized heating of the biological phantom is achieved by pumping a saline solution of pre-selected concentration through enclosed ends of hollow dielectric cylinders having approximately 5cm inner diameter and 4 mm wall thickness. The temperature of the heated zone is preset and maintained to +/-0.2 degrees C by an external heater and circulator. The results currently show that a maximum temperature precision of 0.98 degrees C and maximum relative accuracy of 0.56 degrees C has been achieved in the laboratory using the current generation of the prototype system.

Instrumentation and design of a frequency-domain diffuse optical tomography imager for breast cancer detection

The instrument development and design of a prototype frequency-domain optical imaging device for breast cancer detection is described in detail. This device employs radio-frequency intensity modulated near-infrared light to image quantitatively both the scattering and absorption coefficients of tissue. The functioning components of the system include a laser diode and a photomultiplier tube, which are multiplexed automatically through 32 large core fiber optic bundles using high precision linear translation stages. Image reconstruction is based on a finite element solution of the diffusion equation. This tool for solving the forward problem of photon migration is coupled to an iterative optical property estimation algorithm, which uses a Levenberg-Marquardt routine with total variation minimization. The result of this development is an automated frequency-domain optical imager for computed tomography which produces quantitatively accurate images of the test phantoms used to date. This paper is a description and characterization of an automated frequency-domain computed tomography scanner, which is more quantitative than earlier systems used in diaphanography because of the combination of intensity modulated signal detection and iterative image reconstruction.

Refined solution structure of the glucocorticoid receptor DNA-binding domain

A refined solution structure of the glucocorticoid receptor DNA-binding domain (GR DBD) has been determined using two- and three-dimensional nuclear magnetic resonance (NMR) spectroscopy on an 15N-labeled GR DBD fragment in conjunction with distance geometry and simulated annealing calculations. Thirty structures of the fragment C440-R510 of the rat GR were calculated based on 906 distance constraints obtained from NOE intensities (168 intraresidue and 738 interresidue NOEs) and 43 dihedral constraints. Average atomic root mean square (rms) differences between the 24 best structures and their geometric average are 0.70 A for backbone atoms and 1.44 A for all heavy atoms. Several regions that were not well defined in a previous NMR structure determination of a similar protein fragment [Härd, T., Kellenbach, E., Boelens, R., Maler, B.A., Dahlman, K., Freedman, L.P., Carlstedt-Duke, J., Yamamoto, K.R., Gustafsson, J.-A., & Kaptein, R. (1990b) Science 249, 157-160] are now well-defined. The refined structure of the uncomplexed GR DBD is very similar to the crystal structure of GR DBD in a sequence specific DNA complex [Luisi, B. F., Xu, W. X., Otwinowski, Z., Freeman, L. P., Yamamoto, K. R., & Sigler, P. B. (1991) Nature 352, 497-505], in particular with regard to the presence and relative positions of secondary structure elements. The backbone atom rms difference between the average NMR solution structure and the crystal structure of the DNA-complexed GR DBD is 1.8 A. The most pronounced differences between the free and DNA-complexed states are found within the fragment C476-C482 in the second zinc-coordinating domain.(ABSTRACT TRUNCATED AT 250 WORDS)

Deletion of the DXS165 locus in patients with classical choroideremia

Using various probes from the Xq21 region which is known to carry the choroideremia (tapetochoroideal dystrophy, TCD) locus, we have screened the DNAs from eight unrelated male choroidermia patients for microdeletions. In two of these patients, but not in any of 45 males tested as controls, lack of hybridization signals with probe plbD5 suggested a deletion encompassing the DXS165 locus and (part of) the TCD gene. Absence of additional clinical features in these patients and the fact that two closely linked, and probably flanking, TCD markers (DXYS1 and DXS72) are not deleted may indicate that the physical distance between the DXS165 locus and the TCD gene is small.

Regional localisation of X chromosome short arm probes

Nine human X chromosome-specific clones have been isolated by screening an X-chromosomal genomic library with fetal muscle cDNA. Five of the clones have been localised to the short arm and four to the long arm. The short arm probes have been regionally assigned using a panel of somatic cell hybrids. They have been mapped further using a series of DNA samples from male patients with different deletions of the region Xp21, and having complex phenotypes including Duchenne muscular dystrophy. The use of these probes in the mapping of the short arm of the X chromosome is discussed.

Perirenal lymphoma. Report of a case

A patient with fever and abdominal pain was examined with ultrasonography and CT. The two methods demonstrated an isolated perirenal mass but the exact nature of it could not be established. Ultrasonographically guided coarse needle biopsy and the following histopathologic examination of the biopsy core demonstrated a malignant lymphoma.

The Matching Familiar Figures Test: a primary, secondary, and tertiary evaluation

Analyzed the Matching Familiar Figures (MFF) Test, which has been employed by researchers to determine conceptual tempo, for potential use as a tool for the clinician. The literature indicates that the test is valid in terms of range and structural clarity of information provided. The psychological factors inherent in impulsivity are discussed, along with some significant implications of the MFF that justify its further development. Currently, the primary deficits are a lack of norms as well as an alternate form. Several crucial advantages of this test are listed that favor its use in a clinical environment.

Impulsivity: a multidimensional concept with developmental aspects

Fifty-five preschool children were administered a number of tests purported to measure impulsivity: Delay of Gratification, Walk-the-Line-Slowly, Matching Familiar Figures Test, Schenectady Kindergarten Rating Scales, a teacher rating scale, and the Porteus Maze Test. Analyses indicated that impulsivity is multidimensional, with age-, sex-, IQ-, and teacher-related types. The results suggested that multiple indices are essential to the measurement and study of impulsivity. An interaction between sex and age of child was also revealed with respect to type and rate of activity. While 3- and 4-year-old girls differ radically from boys in type and rate of motor activity (fine muscle vs. gross muscle), 5-year-olds were virtually identical.

Construct validation of children's behavior problem dimensions: relationship to activity level, impulsivity, and soft neurological signs

A construct validation study of dimensions of children's behavior problems was carried out with use of multiple linear regression. The Ss were 76 latency-aged boys in residential treatment. The dimensions involved were Conduct Disorder and Inadequacy-Immaturity. The predictor variables were activity level, impulsivity, and soft signs of neurological damage. Results indicated that Conduct Disorder was significantly predicted by activity level, in combination with impulsivity. Inadequacy-Immaturity was significantly predicted by activity level and soft signs. A third dimension, Personality Disorder, was found to be uncorrelated with the three predictor variables.

Reflection-impulsivity and level of maturity

It was hypothesized that scores on the Matching Familiar Figures Test (MFF) are related to level of maturity. To test this hypothesis, 76 latency-aged boys in residential treatment were administered the MFF and a gross motor coordination test and were assessed for soft signs of neurological damage. Also included were age, IQ, and reading scores, along with ratings of behavior problems, activity, and impulsivity levels. A factor analysis yielded a factor (Factor II) consisting of MFF errors, age, soft signs of neurological damage, and gross motor coordination. Another factor (Factor IV) consisted of MFF errors and MFF latency. Factor IV provides support for the reflection-impulsivity construct, while Factor II may suggest that scores on the MFF are partially a function of physiological maturity and that errors contribute more than latency to the determination of reflection/impulsivity.

[High frequency cinematographic investigations of the mode of operation of common grinding instruments on bone and cartilage (author's transl)]

The mode of operation of grinding faces, rod diamonds and diamond grinding heads which are expecially employed in oto-surgery was investigated in slow motion pictures with the aid of high frequency cinematography. The R.P.M. ranged between 5,000-80,000, the picture frequency was usually 6,000 pictures per second. Full efficiency of the diamond grinding heads (DS) is only guaranteed by adequate flushing. Water stream flushing and drop flushing (drop sequence depending on R.P.M.) must be centered on the grinding head, as increased soiling due to filling of the diamond surface occurs otherwise. Because of the fixed mounting of the spray tube in the direction of the shaft, spray flushing is most useful, although not unsable for diamond faces. Due to its very fine-rough surface, the DS produces grinding dust by abrasion from the bone or cartilage which is readily distributed in the airspace over the whole working area. The same does also apply to finely atomized fluid sprays. Cutting is performed tangentially. The percussing DS touches the bone only with a small part of its surface and easily gets soiled. Depending on the R.P.M., the cutting speed was 10,000-80,000 R.P.M. These values also apply for the fluid dropping rate. Contrary to the rose bit or the surgical fraises, the DS got soiled more easily and produced definitely finer cuts.

[Experiences with a new bone drill for surgery of the ear and nose (author's transl)]

Surgical drilling similar to that developed by Kaltenbach and Voigt for bone work on the ear, nose, maxilla, hand and vertebrae can be used at up to 80,000 rev/min without undesirable heat production. Drill-bits with the normal shaft length of 45 mm remain steady at 80,000 rev/min, but drill-bits of 70 mm length sometimes vibrate. The size of drill head and rate of revolution in this respect are related proportionately especially with cutting as opposed to diamond drill-heads. In ear surgery this method is only suitable on certain conditions. In nasal surgery it is useful for the transverse osteotomy with a 45 mm long circular saw.

[High frequency cinematographic investigations of the mode of operation of common drilling instruments on bone and cartilage (author's transl)]

High frequency cinematographic films were made of the mode of operation of common oto-surgical drilling instruments on bone and cartilage. Rose bits and surgical fraises of different sizes were used at 5,000-80,000 R.P.M. The evaluation of the slow motion pictures was performed on the running films and by review of single frames. In detail: The preparation of the drilling head on the bone without simultaneous flushing leads to a filling of the cutting channel and decreased cutting. Drop flushing only prevents the increasing soiling of the drilling head if the drop sequence is rapid and which must be markedly increased with increasing R.P.M. of the drilling instrument. Flushing with a stream of water, which definitely prevents soiling, is preferable. Both drop flushing as well as the water stream must continuously wet the drilling head, i.e. must be absolutely centric in every case. Safest is the automatic spray flusing which is mounted on the handpiece, but which has so far not been used in oto-surgery. During the preparation, the air space of the working area is always filled with drilling dust or haze. Cutting is always performed tangenitally. The cutting speed lies between 2,9 m/s to 16 m/s. It depends on the R.P.M. of the drilling instrument. A drill head running out of true, even with a gently percussing shaft, touches the bone only with a part of its cutting surface which strikes more vigorously than desired and easily gets soiled, despite flushing. Cutting is therefore less and uncontrolled. An increased feeding energy (pressure on the support) in order to speed up cutting leads to heavy wear of the drilling instrument and unsafety in handling due to jumping of the drilling head. During each contact of a cutter with the bone, coarse fraises with low R.P.M. (5,000 R.P.M. = 83 R/s) show a short stopping of the rotation which results in a jerk and vibration of the whole preparation and can thus lead to a damage of the inner ear.

[Progressive necrotizing otitis externa in diabetics with disorders of the cerebral nerves (author's transl)]

The disease occurs without exception in elderly diabetics. Pseudomonas aeruginosa (pyocyaneus) is always found in the secretion. In our reported case of a 71-year old man appeared in addition to a fetid, festering, granulating otitis externa, disturbances of swallowing, hoarseness and severe occipital headaches appear after five months. Neurologically, the N. glossopharyngeus, the N. recurrens and the N. hypoglossus were shown to be paretic. The inflammatory process has pushed forward via the bone of the auditory meatus on to the base of the skull to the jugular foramen and the foramen lacerum. Surgical removal of the inflammatory changes and subsequent treatment with carbenicillin is recommended as the treatment of choice.

[Bacterial airborne dispersal during the drilling of infected bone (author's transl)]

The hazards of infection by bacterial airborne dispersal secondary to drilling bone in the surgical treatment of infection of the air spaces of the skull were assessed experimentally. This included estimation of the furthest distance that the cooling fluid, using coloured water, and the bone chips of a dry petrous temporal bone can be thrown, and the spread of the fine dust produced by the drilling using a staph. albus suspension as the rinsing fluid. The drops and bone chips were flung to a distance of about 90 cm in the working area around a cutting burr rotating at 80 000 r.p.m. The fine dust thrown off by cutting and diamond burrs and the infected fluid mist stays suspended in the air for hours and can be carried across the whole room by air currents. The surgeon and operating theatre personnel are therefore always at risk of infection. Preventive measures are discussed.

[How important are lower tunnels in the cottle septoplasty? (author's transl)]

The Cottle method is the best for correction of anterior nasal septal deformities. Establishment of the lower tunnel however seems unadvisable because of the common damage to the nasopalatine nerve passing through the incisive foramen with occasional permanent sequelae. The procedure also is time-consuming. As a rule spurs or deviations can be dealt with after establishing upper tunnels without perforation of the mucoperichondrial or mucoperiosteal flaps. The method is described in details.

[Histological examinations about possible heat lesions of bone and cartilage during boring and grinding (author's transl)]

In skull bone and septum cartilage holes were bored with rose trepans and diamond cutters of various sizes (2-20) and at different revolutions (5,000-42,0000 rev/min) with and without the use of cooling fluid. The specimens were examined histologically. Borings with rose trepans without cooling fluid cause sometimes considerable heat lesions up to a depth of 30 mu. Bone shows the more severe lesions. The use of cooling fluid reduces the damage quite considerably (burns zone up to a maximum depth of 12 mu). In the normal range of up to 10,000 rev/min practically no heat lesions occur. In the high range above 20,000 rev/min the lesions are often only plaque-shaped. Water jet or spray cooling is superior to droplet cooling. Diamond cutters cause more severe lesions. Boring and grinding in the highest range (up to 300,000 rev/min) without cooling fluid cause very deep burns (up to 56 mu),

[Investigations on the shape and size of bone-chips produced during boring and grinding (author's transl)]

Examinations of the shape and size of chips produced during boring and grinding of dry macerated and fresh temporal bone by various drills and grinders at different revolutions show that rose trepans mainly scrape fresh bone, producing large rolled-up chips, but knock off dry macerated bone, producing more compact chips of bizarre shape. In either case the chip waste also contains plenty of fine and finest compact chips which are broken off and splinter during the removal or knocking-off of the chips from solid bone. The size of the chip depends on the size of the drill head. Diamond cutting heads produce fine and finest compact bone chips. Bone milling produces plenty of scrapes even from dry macerated temporal bone. The rate of revolutions (10,000-80,000 per min) had no influence on the shape and size of chips. Clinically the scraped chip seems to be the most favourable in the drilling of bone because it causes least damage. The use of a drill head with sharp-edged, intact cutting surfaces seems important for this, with continuous rinsing during the boring process to prevent soiling of the interspaces between the cutters and to ensure full performance in accordance with their construction.

[Noise level measurements of the air noise during drilling and grinding on the fresh isolated temporal bone (author's transl)]

Aerial sound measurements with different drilling instruments were performed during dry running and preparations of the bone. Registered were the values of the small drilling instruments Sirona, Dentatus-Air, and Electro-Torque-Ritter. Also tested were the KaVo-Technique-machine, the Hall-machine, the Air-Orbit-turbine, and the Sirona-turbine. During dry running most of them already reached the allowed marginal value of noise nuisance for the ear of 85 dB (A) at a distance of 35 cm. Only the Air-Orbit-machine showed a slightly lower value of 80 dB (A). The level increases with the used handpieces. Normal handpieces 1:1 exert only a minimal influence, gear handpieces 2:1, however, markedly increase the level. The verticity is of no importance in the range of normal rotations between 10,000 r/min. and 80,000 r/min. Only rotations in the lower frequency range of 2,000 r/min. markedly decrease the noise level. During bone drilling, the kind and size of the drilling bit have an influence on the intensity of the noise level. Quadruple wing milling cutters create a very high noise level (at a distance of 15 cm still above 110 dB [A!]), big rose cutters (R 16) create noise levels of 95 dB (A) and above, and only diamond round bits create less noise (approximately 88 db [A]). Small drilling bits make such a faint noise, that it is overroared by the drilling instrument. The turbines create only slightly higher levels than during dry running. Larger drilling bits cannot be employed here on principle. Wing milling cutters can lead to persistent damages of the inner ear. The frequent use of dental drilling instruments for bone preparations can also lead to a hearing loss of the operator in the long run.

[Measurement of sound transmitted through the body while drilling and grinding isolated petrous temporal bone (author's transl)]

Measurements of the effect of rotating drills and grinders on isolated fresh temporal bone on the sound transmitted through the body have not previously been made known. In contrast to measurement of air-conducted sound, they include the portion of sound which effects the hearing apparatus of the patient through the bone during the process of drilling the temporal bobe. Measurements were made with a calibrated acceleration pick-up in conjunction with a precision sound level meter (test amplifier with sound frequency analyser). The recording was made continuously between 20 Hz and 20 000 Hz. The range between 250 Hz and 8000 Hz was examined mathematically. Above 8000 Hz the curves dropped markedly, apart from a few exceptions. The level of the sound depends largely on the size of the drill bit, and consequently on the breadth and depth of the rotating cutting edges. The smaller drill heads produce a considerably smaller quantity of sound. The highest level of sound comes from the burrs and wing-cutters. The diamond head lies lower in the scale, but almost equals the effect of the steel drills. The speed of rotation of the drill head plays only a subordinate role. Between 16 000 and 80 000 r.p.m. the values are the same. In the region of 10 000 r.p.m. the sound level is frequently reduced, even if a few loud peaks may still occur here. The type of drilling machine, the handpiece or transmission handpiece used have no effect. Altogether, the rotary drill produces less sound transmitted to the inner ear through the body than through the air.

[Facial paresis following stapedectomy (author's transl)]

An ususual complication after stapedectomy for otosclerosis is reported. After two vain attempts elsewhere, the tympanic cavity was opened for the third time. Since the incus was missing, a malleovestibuloplasty was undertaken, using the Schuknecht wire prosthesis. Hearing was very good. One day after the operation, a facial paralysis developed, and increased over the following days. After 18 days, the nerve was found to be oedematous and swollen above the fenestra ovale upto the level of the promontory and had forced the prosthesis out of the fenestra ovale. Six weeks later, nerve function was normal.

[Microcoagulation in the treatment of facial spasm (author's transl)]

A method for the surgical treatment of facial spasm is described. The nerve trunk is exposed in the mastoid region and the sheath is opened. With a bipolar electrode, microspots are burnt spirally round the nerve trunk and also at a few places in the centre of the nerve after pulling the bundles apart. Three cases are reported and assessed in comparison with the methods of Miehlke, Fisch, Rosemann and Schaupp. The more rapid and easier delineation of the nerve trunk in the event of a recurrence are considered an advantage compared with the extratemporal methods.