A micro-computed tomography study of the sinus tympani variation in humans.

BACKGROUND: The posterior part of the tympanic cavity comprises a depression called the sinus tympani (ST). The said structure is of outmost importance, e.g. in surgical procedures involving the middle ear, as a pathology (microbial biofilm or cholesteatoma) present in this difficult to access location might hinder its effective treatment. The aim of the study was to evaluate anatomical variants of the ST in human adult petrous bones. For this purpose, three-dimensional (3D) models of the ST were recreated from micro-computed tomography (CT) scans of 44 dry petrous bone samples (19 female, 25 male), applying 3D Slicer, Meshmixer and MeshLab software. MATERIALS AND METHODS: Anatomical variants of the ST were classified in terms of both shape and surface configuration. The internal configuration of the ST was classified as heterogeneous - containing small bony trabeculae and crests up to 1.0 mm in size, contrasting to homogeneous ST that characterizes a relatively smooth interior, or mere presence of minor depressions and mild folds. Female STs were more bowl-shaped (57.9%) than saccular (42.1%), and had heterogeneous surface configuration (52.6%) compared to homogeneous (47.4%). On the contrary, male STs were more saccular (52.0%) rather than bowl-shaped (48.0%), and predominantly had a heterogeneous surface (84.0%) over homogeneous (16.0%). RESULTS AND CONCLUSIONS: A complex combination of ST features comprised of a saccular shape and heterogeneous surface occurred in 52.0% of males and in 15.8% of females (a statistically significant difference; p = 0.0254, Fisher's exact test) seems to be clinically important because of its potential negative implication on health outcomes after surgery in the case of, for example, cholesteatoma, and it may also favour chronic pathological processes.

A new method to estimate 3D cell parameters from 2D microscopy images.

Optical microscopy has been a basic and standard technique in cell biology research for decades. Microscopy techniques function well for thin, optically transparent cultures and allow for the imaging of thicker biological specimens. There is no better method of in vitro cell observation and analysis, hence microscopic techniques are extensively used and constitute an optimal tool for cell culture studies. This paper proposes an original methodology of optical microscopy data processing based on the phase contrast technique during cell culture monitoring. By exploiting images recorded during cell proliferation, a surface reconstruction was performed based on assumption, it can be considered that the local brightness of the image depends on the cells' thickness and thus the obtained results can be interpreted in the form of a surface that represents a three-dimensional structure, which allowed for a quantitative description of the cell evolution. The 3D data obtained enabled the investigation of parameters describing the morphology of the cells and the topology of their proliferation. These parameters included cell sizes in plane but also in the direction perpendicular to it, cell volume changes, their spatial distribution, as well as anisotropy and directivity. The method presented provides data carrying information similar to that obtained using a holographic microscope, e.g. A HoloMonitor (Phase Holographic Imaging PHI Inc.), or from confocal scanning microscopy with the "z-stack" mode. The techniques of bright field or phase contrast cell observation are, however, much cheaper, and widely available when compared to holographic microscopy, for instance. Besides, these also enable monitoring of cell activity over time, i.e. the study and quantitative description of dynamic changes in the cells. The proposed approach uses generally available free tools such as ImageJ software with BoneJ and Particle Analyzer plugins. The methodology is suitable for even a basic microscope, it can be easily implemented as a script, and thus data processing can be significantly shortened, the methodology can be automated, and also applied for data processing in real time.

Micro-imaging of implanted scaffolds using combined MRI and micro-CT.

RATIONALE AND OBJECTIVES: Thanks to the advanced studies in biomaterial engineering a panoply of polymers can be used to manufacture porous scaffolds for bone tissue regeneration. Suitability of the scaffold for its purpose is determined by factors like size of the pores, its orientation and shape, as well as biocompatibility of the material. Even though a variety of analysis methods is available for in vitro studies, investigating the process of bone reconstruction on implanted scaffold meets with difficulties. METHODS AND MATERIALS: Polylactide porous sponges imbued in hydroxyapatite were implanted into long bones of white New Zealand rabbits for 3 months. The bones obtained from the animals were subjected to MRI and µCT imaging. The obtained images were subsequently fused together. RESULTS AND CONCLUSIONS: Combined MRI and µCT resulted in high resolution diagnostic images which allow for: implant positioning, inflammation divulgement, rating degree of implant resorption, observation of newly formed trabeculae, texture analysis and other quantitative measurements.

Differences in the mineral density of lower limb bone tissue in a healthy population sample.

This article presents the results of research to evaluate the impact of the functional asymmetry of the lower limbs on the precision of the densitometric measurements used in the diagnosis of metabolic bone diseases and in monitoring treatment outcomes. The study subject were 46 healthy adults, in whom the mineral density of the bone tissue (BMD) was measured in the proximal epiphysis of the femoral bone in both the left and right lower limb. In 43 of the analyzed cases (94%), higher BMD was found in the dominant extremity (avg. 2,8%, range 0,6-11,8%). Although lateralization of the lower limbs was confirmed in every case in this population sample, no statistically significant differences in BMD were found between the dominant and subdominant limb. However, due to the large differences in BMD found in individual cases, control DEXA measurements should always be taken from the same side when monitoring the outcome of metabolic bone disease treatment in individual patients.

The most common errors in the densitometric diagnosis of osteoporosis.

A review of world literature on the subject indicates that, given the present state of our knowledge, and the technological possibilities and availability of the apparatus, the most useful method for the evaluation of bone metabolism, especially the diagnosis of osteoporosis, is dual energy X-ray absorptiometry (DEXA). However, this method is not free of errors that can exert a negative impact on the final results of examination. On the basis of heir own experience, the authors have presented here the most common errors encountered in the densitometric technique. A DPV-L densitometric apparatus (Lunar Corporation) was used in this research. Errors in densitometric testing are divided into three groups: those dependent on the object investigated, those dependent on densitometric data analysis, and others. In the first group we took into account factors which can lead to either overestimating (+) or underestimating (-) the final test results: degenerative changes (+), scoliosis (+), the presence of foreign bodies, such as metal (-), status post fracture (+), the presence of pathological structures (+ or -), osteoporotic fractures (+), and incorrect arrangement of the investigated object (+ or -). Errors in data analysis included erroneous data entry regarding the patient's age, height, body mass (affecting the value of the Z-score), and sex (distorting the T-score and the Z-score), and incorrect settings regarding the measurement field. Other errors to densitometric technique included failure to calibrate or improper calibration of the measurement apparatus and errors in computer programming. Individual errors were responsible for falsifying results from 1 to 37%. If several of these errors are accumulated, the accuracy of examination may change more than 100%. Densitometric examinations of the lumbar spine are the most subject to error. The repeatability of the results generated by the DEXA apparatus (as stated in the equipment specifications) ranges for particular skeletal regions from 0,9% to 2,5% of the coefficient of variance, while the precision ranges from 3% to 5%. This means that even if we follow the strictest guidelines for test procedures, the margin of error is still several percent. We also cannot exclude the impact of errors of the three types listed above on the final results. We are convinced that the DEXA method is an excellent instrument for the diagnosis of osteoporosis (in static bone evaluation). However, its value diminishes in monitoring dynamic changes in bone tissue, even at 1-2 year intervals.

[Functional assessment after operative treatment of femoral shaft fracture]. / Ocena wyniku czynnosciowego po operacyjnym leczeniu zlaman trzonu kosci udowej.

The paper presents results of treatment in 135 patients (aged 16-77 years) with fracture of the femoral shaft treated with one of the four techniques: open intramedullary Küntcher nailing, Zespol fixation, AO plating and closed locked and unlocked intramedullary nailing. The assessment has been based on authors' own 4-grade, 35-points scale involving 7 parameters. Closed intramedullary nailing proved to the most efficient. No reoperation in this group occurred. The percentage of excellent and good results was the highest--96.4% and such was the score--32.6 points. Open methods (Küntcher nailing, Zespol fixation, AO plating) rendered 88.2%, 31.7 points and 59% excellent and good results, 26.2 points in group without complication and reoperated one respectively.

[Dual energy X-ray absorptiometry in Ilizarov lower extremity lengthening: preliminary study]. / Metodyka badania densytometrycznego w wydluzeniach konczyn dolnych sposobem Ilizarowa--doniesienie wstepne.

Ilizarov method for lower extremity lengthening has been employed in 107 patients. Some 25% of numerous complications are bony union disturbances. Dual energy X-ray absorptiometry (DEXA) for assessment of new bone formation was introduced to reduce these problems. Detailed densitometry methodology developed on the ground of 93 measurements in 11 patients is presented. Pre-operative measurement was followed by subsequent evaluations done every 3 weeks after the onset of distraction. DEXA was capable of showing the callus 3-4 weeks earlier than conventional radiography. DEXA allows for adjusting the pace of lengthening to the extent of new bone mineralization, evaluation of lengthening achieved, determining the timing for safe removal of the apparatus. The need for temporary rearranging of the apparatus and troublesome image analysis are among the drawbacks of the method.

[Treatment of compound C2 tibial shaft fracture with Polfix fixator in the pillar version]. / Leczenie zlaman zlozonych trzonu kosci piszczelowej typu C2 sposobem Polfix w wersji filarowej.

Pillar version of POLFIX fixator for treatment of compound C2 tibial shaft fractures presented. The method was employed in 9 cases and in 8 of them (89%) the fracture healed within 32 weeks on an average. In 1 case of IIIB open fracture infection developed and no union has been achieved. The fixator can be designed preoperatively; there is no need to dismantle the template when drilling, tapping or inserting screws what makes an osteosynthesis easy. The method may be used also in metaphyseal fractures. Pillar version of POLFIX fixator proved useful in treatment of compound tibial fractures.

[Fixation of neck-head with a single cannulated screw for slipped capital femoral epiphysis--preliminary report]. / Zespolenie szyjkowo-glowowe jedna kaniulowana sruba gabczasta w przewleklym mlodzienczym zluszczeniu glowy kosci udowej--doniesienie wstepne.

Results of surgical treatment in 7 patients with slipped capital femoral epiphysis have been presented. Slip angle ranged from 12(to 42(. Closed, in situ neck-head fixation with a single cannulated screw was performed. The screw was introduced percutaneously, through the anterior surface of the femoral neck into the center of the head and perpendicularly to its base. The method employed rendered very good results. No head or neck perforation occurred. No progression of the slip was observed. Soft tissue trauma was only minimal; mobilization was commenced the first postoperative day.

[Z-plasty in treatment of snapping hip]. / Plastyka "Z" w leczeniu operacyjnym biodra trzaskajacego.

The study deals with clinical assessment of results of surgical treatment of 13 snapping hips. Bringnall and Stainsby procedure has been employed; the surgical technique has been described. The mean age at the operation was 19 years, mean follow-up was 21 months. In 11 cases (84.6%) the symptoms abated completely. The results justify conclusion, that Z-plasty with transposition of created flaps should be recommended as a mode of surgical treatment for snapping hip.