Individual Anatomical Features Research Articles

Dual-ratio approach to pulse oximetry and the effect of skin tone.

Pulsatile blood oxygen saturation ( ) via pulse oximetry is a valuable clinical metric for assessing oxygen delivery. Individual anatomical features, including skin tone, may affect current optical pulse oximetry methods. We developed an optical pulse oximetry method based on dual-ratio (DR) measurements to suppress individual anatomical confounds on . We designed a DR-based finger pulse oximeter, hypothesizing that DR would suppress confounds from optical coupling and superficial tissue absorption. This method is tested using Monte Carlo simulations and in vivo experiments. Different melanosome volume fractions in the epidermis, a surrogate for skin tone, cause changes in the recovered on the order of 1% in simulation and in vivo. Different heterogeneous pulsatile hemodynamics cause greater changes on the order of 10% in simulations. recovered with DR measurements showed less variability than the traditional single-distance (SD) transmission method. For the models and methods considered here, measurements are strongly impacted by heterogeneous pulsatile hemodynamics. This variability may be larger than the skin tone bias, which is a known confound in measurements. The partial suppression of variability in the recovered by DR suggests the promise of DR for pulse oximetry.

Correlations of teleroentgenometric indicators according to the Steiner method with the dimensions of teeth and dental arches in young men and young women with a physiological bite without taking into account the type of face

Annotation. The importance of teleradiographic indicators in the diagnosis and planning of orthodontic treatment is difficult to overestimate, but their relationship with the size of teeth and dental arches in different age and sex groups remains insufficiently studied. This is especially relevant for the Ukrainian population, where individual anatomical features can affect the effectiveness of orthodontic interventions, which makes the study of such relationships important for improving approaches to diagnosis and treatment. The purpose of the study is to establish the specifics of correlations between teleroentgenometric parameters according to the Steiner method with the dimensions of teeth and dental arches in Ukrainian young men and young women with a physiological bite. A morphometric study of the teeth and dental arches was carried out, and teleroentgenometric indicators were determined using the Steiner method from the primary computer tomograms of 41 Ukrainian young men (aged 17 to 21) and 68 Ukrainian young women (aged 16 to 20), which were obtained from data bank of the Department of Pediatric Dentistry and Research Center of the National Pirogov Memorial Medical University, Vinnytsya. The evaluation of correlations between teleroentgenometric indicators according to the Steiner method and computed tomographic dimensions of teeth and dental arches was carried out in the license package “Statistica 6.0” using Spearman's non-parametric statistics. As a result of the analysis of the reliable and average strength of unreliable correlations between teleroentgenometric parameters according to the Steiner method with the sizes of teeth and dental arches, it was established: in young men – 5.71 % of similar relationships with the sizes of the teeth of the upper jaw (mostly reliable straight lines of average strength with the sizes of incisors and canines), only 1.79 % with the dimensions of the teeth of the lower jaw and 6.60 % with the dimensions of the dental arches (mainly reliable straight and reverse of medium strength with distances characterizing the position of canines and first premolars relative to the hard palate, as well as the distance between the crowns of the central incisors and the line that connects the molars of the upper jaw); in young women – 4.82 % of similar relationships with the dimensions of the teeth of the upper jaw (mostly reliable straight lines of weak force with the dimensions of canines), 5.00 % with the dimensions of the teeth of the lower jaw (mostly reliable straight lines of weak force with the dimensions of incisors), 14.58 % with the dimensions of dental arches (mainly reliable direct and reverse medium strength with the distances between the crowns of the central incisors and the line connecting the canines, the first premolars and molars of the upper jaw, as well as the distances between the distal and medial roots of the lower first molars). Thus, in Ukrainian young men and young women with a physiological bite, the peculiarities and gender differences of the correlations between teleroentgenometric indicators according to the Steiner method and computed tomographic dimensions of teeth and dental arches were established.

Robot-assisted mitral valve surgery may be supported by patient-specific planning aid in port placement

Robotic-assisted mitral valve surgery is gaining renewed popularity in the global surgical community. Appropriate patient-specific planning is pivotal for the safety and effectiveness of this procedure. One main step in this perspective is represented by the choice of placement of four ports in the right chest, for the introduction of robotic arms. Individual anatomical features (e.g., chest morphology and position of the mitral valve inside the chest) may determine inadequate surgical exposure, conversion to open procedure, or refusal for the technique. Currently, and contrary to robotic-assisted procedures in other surgical specialties, there is no dedicated approach or tool for patient-specific planning aimed at formally addressing these issues preoperatively. Herein, we present a dedicated, comprehensive method entailing: a homemade algorithm for rib segmentation (deep learning approach) and identification of intercostal spaces / candidate port entry sites; semiautomatic definition of a target working volume (mitral valve); definition of dedicated Performance Measure J* based on each potential triad of thoracic ports entry sites. We propose the dedicated J* parameter to better indicate the optimal patient-specific entry port solution than other parameters (h_e, ic, CCI and E). Prospective clinical studies should be based on the J* parameter. We hypothesize that this approach, dedicated to the requirements of robotic-assisted mitral valve surgery, may enhance the safety and the diffusion of this surgical strategy.

THE USE OF A TRAINING 3D-MODEL IN THE TREATMENT OF A PATIENT WITH A PATHOLOGICAL FRACTURE OF THE PROXIMAL PART OF THE FEMUR (CASE FROM PRACTICE)

Prostate cancer is the second most common cause of malignancy in men, with bone metastases being a significant source of morbidity and mortality in advanced cases. Objective. To give a clinical example of a patient with a pathological transtrochanteric fracture of the right femur with displacement of fragments, the presence of metastasis at the fracture site, to emphasize the importance of 3D-training before surgery. Methods. A clinical example with a significant impairment of the function of the right lower extremity against the background of a significant pain syndrome is given. The diagnosis was established: pathological transtrochanteric fracture of the right femur with displacement of fragments, the presence of metastasis at the fracture site. Pre-surgical training was carried out using a 3D-model and total endoprosthetics of the right hip joint with a revision individual implant of the cement fixation type was carried out. The patient fully recovered the function of the right lower limb and hip joint, the pain syndrome was eliminated, and sleep normalized. The use of a 3D-model for preoperative training of surgeons made it possible to rationally limit traumatization of healthy tissues during tumor removal, prevent possible complications and optimize the time of surgical intervention and thus minimize blood loss. Conclusions. The use of a training 3D-model before surgery followed by prosthetics with a special oncological endoprosthesis provided satisfactory functional results and restoration of the patient's quality of life in the given clinical case. The use of a 3D-model is the key to careful preparation for surgical intervention, taking into account the individual anatomical features of the pathological process and adjacent tissues, which allows you to significantly optimize the terms of the operation and reduce blood loss, and also provides valuable experience for further surgical practice.

Exploiting light-based 3D-printing for the fabrication of mechanically enhanced, patient-specific aortic grafts

Despite polyester vascular grafts being routinely used in life-saving aortic aneurysm surgeries, they are less compliant than the healthy, native human aorta. This mismatch in mechanical behaviour has been associated with disruption of haemodynamics contributing to several long-term cardiovascular complications. Moreover, current fabrication approaches mean that opportunities to personalise grafts to the individual anatomical features are limited. Various modifications to graft design have been investigated to overcome such limitations; yet optimal graft functionality remains to be achieved. This study reports on the development and characterisation of an alternative vascular graft material. An alginate:PEGDA (AL:PE) interpenetrating polymer network (IPN) hydrogel has been produced with uniaxial tensile tests revealing similar strength and stiffness (0.39 ± 0.05 MPa and 1.61 ± 0.19 MPa, respectively) to the human aorta. Moreover, AL:PE tubular conduits of similar geometrical dimensions to segments of the aorta were produced, either via conventional moulding methods or stereolithography (SLA) 3D-printing. While both fabrication methods successfully demonstrated AL:PE hydrogel production, SLA 3D-printing was more easily adaptable to the fabrication of complex structures without the need of specific moulds or further post-processing. Additionally, most 3D-printed AL:PE hydrogel tubular conduits sustained, without failure, compression up to 50% their outer diameter and returned to their original shape upon load removal, thereby exhibiting promising behaviour that could withstand pulsatile pressure in vivo. Overall, these results suggest that this AL:PE IPN hydrogel formulation in combination with 3D-printing, has great potential for accelerating progress towards personalised and mechanically-matched aortic grafts.

Angiographic measurement of the superficial temporal artery for potential use in cerebral bypass surgery: a combined radiological and cadaveric study.

This study aims to investigate the microsurgical anatomy of the superficial temporal artery (STA), explore the relationship between STA length and lumen diameter, and develop a reliable radiologic method for selecting STA segments for bypass surgery. This study used 10 cadaveric dissections (20 STAs, both sides) and 20 retrospective radiological examinations (40 STAs, both sides), employing curved multiplanar reformation and flow color lookup table (CLUT) DICOM processing. Measurements included vessel lumen diameters and luminal cross-sectional thicknesses 3mm proximal to the STA bifurcation, 3mm distal to the frontal branch, 5cm distal to the frontal branch, 3mm distal to the parietal branch, and 5cm distal to the parietal branch. The distance between the STA bifurcation and the superior zygomatic border (SZB) was also measured. In our analysis, descriptive statistics encompassed mean, standard deviation (SD), standard error, minimum and maximum values, and distributions. Comparative statistics were performed using Student's t-test, with statistical significance set at p < 0.05. There were no statistically significant differences between STA measurements of bifurcation distances (p = 0.88) and lumen diameters (p = 0.46) between cadavers and radiological measures. However, lumen thicknesses were larger in frontal branches than parietal branches at the seventh and eighth centimeter (p = 0.012, p = 0.039). Branches became thinner distally from the zygoma in both cadavers and radiological image measurements. The CLUT DICOM processing radiological measures provided the high-precision required to enable pre-surgical vessel selection for extracranial-intracranial bypass. The results show that STA vessel luminal diameters are sufficient (> 1mm) for bypass surgery in the first 9cm but gradually decrease after that. Also shown is that the choice of frontal versus parietal branches depends on individual anatomical features; therefore, careful preoperative radiological examination is critical.

Impacted third molar root abnormality with mandibular canal close position as a presupposing factor to inferior alveolar nerve trauma

The aim of the study is reducing the risks of surgical injury to the inferior alveolar nerve, by taking into account individual topographic and anatomical features, improving diagnostic methods, and techniques for removing retinated teeth with a close fit to the mandibular canal. An examination was conducted in the Department of Surgical Dentistry (CBCT/OPG) and surgical treatment of 223 patients, with a close fit of the roots of the retinated lower third molar to the mandibular canal. Microslips of teeth with roots intact during removal (n=96) of the main group and the control group (n=52) were prepared with a Micromet Remet manual petrographic machine. The sections were carried out along the longitudinal axis of the tooth with the capture of the area of close fitting of the nerve, the teeth from the control group were sawed longitudinally along the axis of the root. The measurement of the macroanatomic features of the roots was carried out with a micrometer (MCC-MP-100 0.001 electronic «CHEESE», manufactured in the Russian Federation), measurements of the thickness of dentine and cement tissues on macroglyphs were carried out using a microscope calibration ruler with an accuracy of 0.01 mm. In the main group, three types of attachment of the mandibular canal to the root of the third molars were distinguished: 20 (96) cases of inter-root attachment of the mandibular canal, 42 (96) apical, 34 (96) lateral (buccal and lingual). A number of anomalies in the structure of the roots of the third molars have been revealed, which are a factor in injury to the neurovascular bundle of the mandibular canal during tooth extraction. The surface of the roots, as well as the microscopes of the tooth sections adjacent to the mandibular canal, were studied under a microscope. A number of specific anomalies of the roots of retinated third molars formed by root dilaceration, thinning of cement tissues, hypercementosis, which are formed at the site of the mandibular canal.In the presence of a deep indentation on the root of the tooth, as well as in the presence of areas of apical hypercementosis in the form of a «spike», the probability of nerve injury during tooth extraction increases many times, which must be taken into account when removing retinated third molars.

Features of trigeminal nerve exit on the base of the brain: neurovascular conflict

The trigeminal nerve is a complex anatomical formation that performs very important tasks in terms of functionality. This article focuses on the study of the exit of the trigeminal nerve and its syntopy with arteries. It is the study of the location of nearby vessels relative to the nerve and their neurovascular conflict that determines the relevance of this work. The prevalence of trigeminal neuralgia (TN) is quite high and amounts to 40–60 patients per 100,000 population, and the incidence according to the World Health Organization is within 2–4 people per 10,000 population. The maximum risk of neurovascular conflict is observed in the age group of people from 45 to 60 years. It is also known that women suffer from neuralgia significantly more often than men. Not only the exact diagnosis, but also the selection of the most appropriate treatment tactics will depend on the result of studies of the individual anatomical features of the pons area. The authors of the article studied 17 preparations of the base of the brain of middle-aged individuals, fixed in a 7 % formalin solution. Of the 17 preparations studied, neurovascular relationships were noted in 14, which is 82.4 % of the total. As a result of morphometric measurements, the data on the length and width of the pons, the thickness of the trigeminal nerve roots, and the middle cerebellar peduncles were obtained. Statistical data processing and photographic documentation were carried out. The clinical manifestations of the disease, diagnostic options, and various methods of treatment were considered. The most effective method of treating neurovascular conflict is surgery, the first mention of which dates back to 1934.

The role of 3D modeling in pancreas surgery: a review

INTRODUCTION: Surgical interventions on the pancreas are technically complex and are accompanied by a fairly large number of complications, which is largely due to the variant anatomy of the pancreas.OBJECTIVE: The aim of this paper is to evaluate the possibilities of 3D modeling in the surgical treatment of pancreatic diseases according to the literature.MATERIALS AND METHODS: Literature searched in Russian and English for the period from 2017 to 2022 in Medline/PubMed, RSCI/Elibrary, CyberLeninka, Google Scholar databases. The search was conducted on the keywords: pancreas, chronic pancreatitis, pancreatic cancer, pancreatic resection, computed tomography, 3-D modeling, 3-D reconstruction, surgical planning, surgical intervention, pancreas, chronic pancreatitis, pancreas cancer, pancreatectomy, computed tomography, 3-D modeling, 3D reconstruction, surgical planning.RESULTS: 49 publications on various aspects of the use of 3D modeling in pancreatic surgery were included in the final analysis. The diagnostic value of building three-dimensional models in assessing the resectability of pancreatic tumors, identifying individual topographic and anatomical features of the pancreatobiliary zone, which should be taken into account during surgery to avoid intra- and postoperative complications, is shown. Examples of a description based on 3D modeling of rare vascular anomalies and cysts that are not visualized according to standard computed tomography in patients who are scheduled for pancreatic surgery are presented. The importance of postoperative 3D modeling of the pancreas for assessing the adequacy of the surgical intervention and early detection of possible complications of the operation is indicated.CONCLUSION: 3D modeling is an innovative and promising diagnostic method that allows increasing the information content of standard computed tomography in pancreatic surgery. 3D models make it possible to select patients for pancreatic resection and substantiate the most optimal surgical strategy. In the future, we should expect an improvement in the results of surgical treatment of pancreatic tumors and complicated pancreatitis.

ANATOMO - MORPHOLOGICAL FEATURES OF AN EDENTULOUS UPPER JAW

Introduction: The success of prosthetic and implant treatment is determined by the knowledge of the anatomical and morphological features of upper and lower edentulous jaws and the identification of landmarks in the prosthetic field that contribute to accurate planning of the complete rehabilitation of the oral cavity. Purpose: This article aims to present and analyze anatomical and morphological features of an edentulous upper jaw that are important for the prosthetist. Materials and methods: A search was conducted in the period from October 2022 till December 2022 in the electronic databases PubMed, Google Scholar, ScienceDirect and several other bibliographic databases using the following keywords: anatomical features, upper jaw, atrophy, residual bone, complete prostheses, edentulous patients. Only literary sources in English, German, Bulgarian and Russian language were included. Rеsults: A total of 1076 articles were identified by the literature search, and the title and abstracts of the articles were examined. Twenty-eight original research studies met the inclusion criteria. Data and evidence were extracted for the importance of anatomical landmarks and features of the prosthetic field in case of complete tooth loss during prosthetic treatment. Conclusion: Individual anatomical and morphological features, age-related and functional changes that occur after complete tooth loss create conditions for prosthetics that must be tailored to the specifics of each individual clinical case and require an individual approach.

Preoperative assessment of the individual anatomy of the superior petrosal vein complex using balanced fast field echo magnetic resonance imaging.

Here, we sought to examine the validity and reproducibility of balanced fast field echo (bFFE) for assessing superior petrosal vein (SPV) complex (SPVC) anatomy. Preoperative bFFE or equivalent scans and operative videos were studied and directly compared with regard to the individual anatomical features of SPVCs and their relation to the operative field. The anatomical details of the bFFE findings of the non-operated side (group 2) of all 50 patients were then reviewed, including the presence of petrosal-galenic anastomosis, and finally compared to the operated SPVCs (group 1). A complete correlation between bFFE and intraoperative findings was observed in 62% of cases and had a significant correlation with 3 Tesla magnet strength and higher pixel bandwidth (rbis = -0.47; p = 0.005). The sensitivity and specificity of bFFE magnetic resonance imaging were 93.7 and 95.2%, respectively, for detecting an SPV disturbing the operative field, and 97.3% and 95% for a disturbing tributary, respectively. Each group had 50 SPVCs, with a total of 70 and 64 SPVs, 10 and 11 general SPVC configurations, as well as 29 and 28 different individual anatomical variations in groups 1 and 2, respectively. Both groups had 1-3 SPVs with a similar distribution of frequencies [Chi-square (4) = 27.56; p = 0.0145 (Fisher's exact test)]. The similarity of the general configurations was not statistically significant. The same four predominant configurations constituted 80% of the SPVCs in each group. The vein of the cerebellopontine fissure was most frequently found in 86% and 88% of cases, and a petrosal-galenic anastomosis was seen in 38% and 40% of groups 1 and 2, respectively. Individual SPVC variations are extensive. Good quality bFFE or equivalents are feasible for preoperative SPVC assessments. However, methods improving vascular visualization are recommended.

Reconstruction of massive bone defects after femoral tumor resection using two new-designed 3D-printed intercalary prostheses: a clinical analytic study with the cooperative utilization of multiple technologies

BackgroundTo reconstruct massive bone defects of the femoral diaphysis and proximal end with limited bilateral cortical bone after joint-preserving musculoskeletal tumor resections, two novel 3D-printed customized intercalary femoral prostheses were applied.MethodsA series of nine patients with malignancies who received these novel 3D-printed prostheses were retrospectively studied between July 2018 and November 2021. The proximal and diaphyseal femur was divided into three regions of interest (ROIs) according to anatomic landmarks, and anatomic measurements were conducted on 50 computed tomography images showing normal femurs. Based on the individual implant-involved ROIs, osteotomy level, and anatomical and biomechanical features, two alternative 3D-printed prostheses were designed. In each patient, Hounsfield Unit (HU) value thresholding and finite element analysis were conducted to identify the bone trabecula and calcar femorale and to determine the stress distribution, respectively. We described the characteristics of each prosthesis and surgical procedure and recorded the intraoperative data. All patients underwent regular postoperative follow-up, in which the clinical, functional and radiographical outcomes were evaluated.ResultsWith the ROI division and radiographic measurements, insufficient bilateral cortical bones for anchoring the traditional stem were verified in the normal proximal femur. Therefore, two 3D-printed intercalary endoprostheses, a Type A prosthesis with a proximal curved stem and a Type B prosthesis with a proximal anchorage-slot and corresponding locking screws, were designed. Based on HU value thresholding and finite element analysis, the 3D-printed proximal stems in all prostheses maximally preserved the trabecular bone and calcar femorale and optimized the biomechanical distribution, as did the proximal screws. With the 3D-printed osteotomy guide plates and reaming guide plates, all patients underwent the operation uneventfully with a satisfactory duration (325.00 ± 62.60 min) and bleeding volume (922.22 ± 222.36 ml). In the follow-up, Harris Hip and Musculoskeletal Tumor Society scores were ameliorated after surgery (P < 0.001 and P < 0.001, respectively), reliable bone ingrowth was observed, and no major complications occurred.ConclusionsTwo novel 3D-printed femoral intercalary prostheses, which achieved acceptable overall postoperative outcomes, were used as appropriate alternatives for oncologic patients with massive bone defects and limited residual bone and increased the opportunities for joint‐preserving tumor resection. Several scientific methodologies utilized in this study may promote the clinical design proposals of 3D-printed implants.

Microanatomy features in third molars roots adjacent to mandibular canal

Of the study is to reduce the risk of postoperative neuropathy of the inferior alveolar nerve by improving diagnostic methods, assessment of individual topographic and anatomical features and extraction technique of impacted teeth adjacent to the mandibular canal. According to the CBCT examination, orthopantomography and macroscopic examination of removed third molars roots (n=140) the relative position of the mandibular canal and the roots of the third molars were studied. Three variants of close mandibular canal and third molars position have been identified. In the lateral and apical nerve position, the root surface depressions were detected. With inter-radicular position fit, the mandibular canal and the nerve bundle form a «bed» in between impacted tooth roots. The injury of neurovascular bundle prognosis during extraction with an interadicular mandibular position depends on roots anatomy and their convergence degree. If the interradicular distance is less than the diameter of the mandibular canal, nerve injury during tooth extraction is inevitable, in such cases coronectomy is indicated.

LATE RESULTS OF TREATING PATIENTS WITH OCCLUSIVE-STENOTIC LESIONS OF THE AORTA INFRARENAL SEGMENT'S MAIN ARTERIES.

The aim: To analyze the results of surgical treatment in the late postoperative period after using modern types of surgical technologies for occlusive-stenotic atherosclerotic lesions of the infrarenal aorta's main arteries. Materials and methods: The total of 420 patients were operated on. The patient's age ranged from 45 to 87 years (in the mean, 66.7±2.3 years). Men pre¬dominated - 375 (89.29%), and women were 45 (10.71%). According to the ischemia classification by Rutherford - 324 (77%) patients fell under categories 4, 5, 6 of the classification. 98 patients were operated on by the open method, 243 by the endovascular method, and 79 by the hybrid method. We assessed such indices as: postoperative thrombosis, limb amputations, mortality, and repeated operations performed due to complications or unsuccessful results of the primary operation. Results: It was ascertained, a decrease in the number of postoperative complications from 7.87% to 4.39% (t=2,11, p=0,035), repeated operations - from 7.87% to 4.39% (t=2,11, p=0,035), amputations - from 3.63% to 2.19% (t=1,24, p=0,214) and mortality - from 3.03% to 1.09% (t=2,03, p=0,042) in the group where in-depth examination methods were applied, a treatment algorithm based on individual anatomical and hemodynamic features was implemented, techniques for performing operations were improved. Conclusions: The analysis of late results of surgical interventions showed that the largest number of complications was found in the group of patients with multistory occlusive-stenotic lesions of arteries.

COMPARATIVE EVALUATION OF THE TEMPOROMANDIBULAR JOINT STRUCTURES AFFECTED BY TMJ DYSFUNCTION.

The aim: To investigate the individual anatomical features of the temporomandibular joint structures affected by TMJ disorders and compare them with those of asymptomatic patients. Materials and methods: The sample consisted of 41 patients. The study group included 29 patients. The retroposition of the right mandibular head was observed in 16 patients, the anterior position of the right mandibular head - in 13 patients, the retroposition of the left mandibular head - in 19 patients, and the anterior position of the left mandibular head - in 10 patients. The control group consisted of 12 patients with an anterior or central position of the right and left mandibular heads. Results: In the study group, a comparative analysis of the ABC angle on the right and left sides found no statistically significant difference in Student's criterion (p=0.176). In the control group, a comparative analysis of the ABC angle on the right and left sides found no statistically significant difference in Student's criterion (p=0.131). To identify a possible difference in the inclination of the articular tubercle in the study and control groups (anterior position of the mandibular head), calculations were carried out and when comparing two related samples using Wilkinson's T-criteria, the difference is not statistically significant p=0.119. The mean values obtained using Student's criterion did not reveal any statistically significant difference between both groups, р*=0,811. Conclusions: A comparative analysis of the ABC angle in patients with TMJ dysfunction and the control group did not reveal any statistically significant difference. At the same time, there was no statistically significant difference between patients with the anterior and posterior position of the mandibular head.

СОВРЕМЕННЫЕ ВОЗМОЖНОСТИ И НАПРАВЛЕНИЯ ИСПОЛЬЗОВАНИЯ 3D-МОДЕЛИРОВАНИЯ В ОТОРИНОЛАРИНГОЛОГИИ

Today the development of 3D technologies, the spread and improvement of 3D printers, as well as the development and application of new printing materials have contributed to the widespread introduction of 3D printing in medicine. There are many options for using 3D technologies, however, one of the most commonly used areas is preoperative planning. Modern imaging techniques are an important component of the preoperative stage in surgical practice. Using a personalized 3D model the surgeon in detail works out on it the optimal surgical approach, the most important stages of the upcoming operation, taking into account the individual anatomical features of the structure of the area of interest. The realism and practical significance of the operation on a 3D model is achieved due to the complete identity of the area of surgical interest with the patient's organs on a 1:1 scale. The purpose of this review was to present up-to-date information on the possibilities and prospects of using 3D printing in planning surgical interventions in otorhinolaryngology, using 3D modeling technologies in teaching students at the Department of Ear, Nose and Throat Diseases of Belarusian State Medical University. Thus, the prospects for 3D technologies are very large-scale, and they will undoubtedly become one of the most dynamic areas in medicine in the future.

Selective Laser Melting-Sintering Technology: From Dental Co-Cr Alloys to Dental Ceramic Materials

The general term of CAD/CAM technology (i.e., Computer-Aided Design/Compute-Aided Manufacturing) comprises several aspects, such as subtractive manufacturing processes, like milling (soft and hard milling), and additive manufacturing processes, like Selective Laser Melting (SLM), which refers to metallic materials, or Selective Laser Sintering (SLS), which refers to glasses/glass-ceramics/ceramic, or polymeric, or related composite materials produced via powder metallurgy technique. In biomaterials fabrications, the first step in SLM or SLS technology is the digital design of the prosthetic restoration, whereby the patient's individual anatomical and morphological features are precisely described. Afterwards laser-aided melting or sintering is repeated (layer-by-layer) until the complete restoration item is fabricated. A wide range of dental materials can be produced by SLM or SLS technology, e.g., metals and alloys, thermoplastic polymers, glasses/ceramics, waxes, and thermoplastic composites. Thus, it is a promising technology for producing a variety of dental restorations, such as metal-ceramic restorations, all-ceramic restorations, maxillofacial prostheses, functional skeletons, individual scaffolds for tissue engineering, etc. SLM technology is already widely applied for fabricating metal objects for dental (e.g., Co-Cr alloy) and orthopedic prostheses. As a subsequence, in the last decade, researchers' interest has been shifted to SLS of ceramic powders, such as SiO2, Al2O3, SiO2/Al2O3, and ZrO2/Y2O3. This article comprehensively reviews the SLS process and its prospects for producing glasses/glass-ceramic/ceramic materials for biomedical/dental applications. The experimental results clearly show that this very modern additive manufacturing technology does not jeopardize the properties of the ceramic biomaterials' properties.

A scoping review of three‐dimensional ophthalmic anatomy smartphone applications

AbstractPurpose: Patient education and understanding has been shown to improve outcomes by enabling engagement. Information relating to ophthalmic disease and surgery is often complex, pertaining to microanatomy of the eye and adnexa. The use of three‐dimensional anatomical models in clinical consultations is one method that can improve patients' understanding of their ophthalmic condition(s) and procedure(s). Our research group surveyed the current app marketspace for virtual smartphone anatomical models that can be readily deployed in any ophthalmic clinic setting for the benefit of patients and clinicians alike.Methods: We conducted a systematic review of Google's ‘Play Store’ and Apple's ‘App Store’ – the two most commonly used app stores – using the key term ‘eye anatomy’. Apps were excluded if they were not related to ophthalmology and if they did not offer a 3D function that could rotate 360°. All relevant apps were evaluated by three parameters: 3D Features, Highlights individual anatomical features, and Cost.Results: The ‘Play Store’ generated 250 results of which 20 were relevant. The ‘App Store’ generated 211 results of which 12 were relevant. Between the ‘Play Store’ and ‘App Store’ there was an overlap of 7 apps. These apps offered a variety of 3D features including 360° rotation, X‐ray and animation modes, and virtual/augmented/mixed reality options. Of the relevant 25 Google and Apple apps, 76% (19/25) offered a function to highlight individual anatomical features. 32% (8/25) of these apps were free and the remaining 68% (17/25) had a price range from £0.89 to £36.62, averaging at £10.36 per app.Conclusions: The availability of medical smartphone applications has proliferated over the past two decades. Whilst there is a wealth of applications available to aid ophthalmology anatomy learning, further improvements and content regulation from specialists is required to maintain a high standard of content. This study is the first to systematically evaluate smartphone apps within the context of ophthalmic anatomy.

A clinical case of choroidal detachment as choroidal effusion in a child with Sturge-Weber-Crabbe syndrome

Choroidal effusion syndrome is a rare idiopathic condition that occurs predominantly in middle-aged man with hyperopia and is characterized by ciliochoroidal detachment (CD), followed by exudative retinal detachment. To present a clinical case of postoperative choroidal detachment in a child with SturgeWeberCrabbe syndrome after microinvasive non-penetrating glaucoma surgery.&#x0D; RESULTS: This article presents the clinical case of postoperative choroidal detachment in a child with SturgeWeberCrabbe syndrome after microinvasive non-penetrating glaucoma surgery. Against the background of the existing anomalies in the development of an optic disc after antiglaucomatous intervention for decompensated glaucoma, after the normalization of IOP, the patient developed choroid detachment with exudative retinal detachment the next day of operation. After conservative therapy involving bed rest and double instillation of mydriatics for 1 month, the situation was completely resolved and his vision was restored to 1.0.&#x0D; DISCUSSION: The atypicality of our clinical case of CD lies in the overly pronounced exudative component. In addition to the classic CD vesicles, we observed high exudative retinal detachment as well as high retinoschisis, which is extremely atypical for classical CD. Considering the characteristics of congenital syndrome, it is necessary to accurately differentiate atypical CCA from the rare choroidal effusion syndrome, which also includes CCA with retinal detachment, but does not present with retinoschisis. Against the background of conservative therapy with bed rest and two instillations of mydriatics for 1 month, the situation was completely resolved, and the patients vision was restored to 1.0. In the treatment of such patients, it is always necessary to consider their individual anatomical features as well as to understand the detailed pathogenesis of the complications that arise before rushing to repeat surgery.

Innovative method for determining the central ratio of the jaws as an effective clinical method for improving the quality of full removable dental prosthetics

BACKGROUND: In modern conditions, in the widespread clinical practice in the prosthetics of patients with complete edentulism, the anatomical and physiological method and its modifications have become popular. However, for all its reliability and ease of use, this method is not without drawbacks.&#x0D; AIM: Improving the effectiveness of complete removable dentures. By developing a new method for determining the central ratio of the jaws.&#x0D; MATERIAL AND METHODS: An innovative method for determining the central ratio of the jaws was created by improving the functional-physiological method for determining the central ratio of the jaws, using a gnatometer and teleradiographic examination.&#x0D; RESULTS: 100 prostheses were made by this method for 74 patients. A comparative correlation analysis of teleradiographic images with old prostheses before treatment, with a gnatometer in the oral cavity during treatment, and with new prostheses 2 months after treatment was carried out.&#x0D; CONCLUSION: The proposed method for determining the CSF allows highly accurate, in accordance with individual anatomical parameters and features, to determine the bite height and central occlusion of the patient as a model for the reconstruction of the future dentition, taking into account and in accordance with Angles skeletal class.