Canal Size Research Articles

CT correlation of spinal canal diameter with pedicle size for safer posterior cervical pedicle screw fixation.

Utilizing computed tomography (CT) studies, we correlated cervical spinal canal diameters (SCDs) with pedicle size between the C3 and C7 levels to more safely perform posterior cervical surgery. We retrospectively analyzed CT studies for 71 patients with cranial or spinal disorders and correlated the cervical SCD with the pedicle outer width (POW) between the C3 and C7 levels. Patients were divided into normal (SCD ≥12 mm at any level, n = 30) and stenosis groups (SCD <12 mm at any level, n = 41). C7 exhibited the largest SCD and POW values, while C3 and C4 exhibited the smallest SCD and POW values. Moderate correlations (r = 0.3, P = 0.002) were observed at the C3 and C4 levels but no significant correlations were observed from the C5 to C7 levels. For SCD values, the normal group demonstrated significantly greater values between the C3 and C7 levels versus the stenosis group. For POW values, only the C4 level differed significantly between the two groups (P = 0.014, Mann-Whitney U-test). Preoperative pedicle size evaluation remains an essential manoeuvre before performing cervical C3-C7 pedicle screw placement. In 71 cervical CT studies, we found no consistent correlation between POW and SCD values, indicating that it is difficult to estimate POW values based on spinal canal size.

“Skip” corpectomy technique in multilevel cervical spondylotic myelopathy and ossified posterior longitudinal ligament: Outcomes with over 10-years follow-up

Objective Skip corpectomy is a surgical technique that includes C4 and C6 corpectomies and fusion via autografts and a cervical plate and is frequently performed in patients with CSM and OPLL. This study presents long-term clinical and radiological outcomes of 48 patients who underwent skip corpectomy with 10-year follow-up. Methods 48 patients who were diagnosed with CSM or OPLL were included. All patients underwent spinal canal decompression and fusion via skip corpectomy. Clinical assessment was performed using the JOA scoring system. The radiological assessment was performed using plain anteroposterior, lateral, and flexion-extension cervical spine radiographs; cervical spine MR imaging; and cervical spine CT scans. The spinal canal size, spinal cord occupation ratio, cervical lordosis, and T2 signal changes were evaluated preoperatively, and postoperatively. Results The mean follow-up period was 14.6 years (13–20 years). Preoperatively, the JOA score was 11.06 ± 3.09. The mean cervical lordosis was 2.08°±11.74 and the average SCOR was 62.1 ± 14.22. There was a significant improvement in SCOR in the early postoperative period. The average cervical lordosis increased to 13.81 ± 2.51 in the 2nd month and minimal loss of cervical lordosis was observed on the 10th year in two patients. Fusion was achieved in all patients, regardless of the graft type. None of the patients had implant failure and graft or hardware-related complications at the 10th-year follow-up. Conclusion Skip corpectomy provides efficient decompression of the spinal cord and provides adequate sagittal alignment and fusion in patients with CSM and OPLL. Long-term radiological and clinical outcomes of the technique are favorable.

Optic Canal Size is an Indicator for the Accessory Optic Canal: Applications for Anterior Clinoidectomy

BackgroundThe ophthalmic artery normally travels with the optic nerve through the optic canal. However, sometimes, the ophthalmic artery travels through a foramen within the optic strut named an accessory optic canal, double optic canal, or ophthalmic canal. This variant puts individuals at an increased risk for blindness or death during anterior clinoidectomy due to unforeseen hemorrhage of the ophthalmic artery or internal carotid artery when the optic strut is separated from the body of the sphenoid bone. Several features make the accessory optic canal difficult to recognize on imaging: its variant nature, small size, and ability to masquerade as a caroticoclinoid foramen or a pneumatized sphenoidal structure. Hence, improved methods of presurgical identification are warranted. The aim of this study was to assess the size and shape of the optic canal, with and without a concomitant accessory optic canal, to determine whether measurement of the optic canal may provide useful information regarding the presence of an accessory optic canal. MethodsIn 191 dry crania, optic canals with and without concomitant accessory optic canals were assessed for the following parameters: canal area, canal perimeter, circularity, solidity, the axes and aspect ratio of a best fit ellipse, and roundness. ResultsNormal optic canals were found to have a larger area (p=0.036), perimeter (p=0.043), and minor axis of a best fit ellipse (p=0.031) than the optic canals that occurred alongside accessory optic canals. ConclusionsAsymmetry in optic canal size can help indicate the presence of a unilateral accessory optic canal prior to surgery.

Differential diagnosis of prosopalgia of dental patients

Aim. To estimate the size of the areas of the skull holes along the course of the trigeminal nerve in dental patients with prosopalgia according to computed tomography. Materials and methods. Twenty seven dental patients were examined. Clinical methods of examination, palpation, assessment of the intensity pain manifestations using a visual analog scale of pain, clinical index Helkimo. Instrumental methods: gnathodynamometry, spiral computed tomography. Results. The article describes data on the condition of bone canals and skull holes of dental patients with facial pain. 27 dental patients with complaints of pain in the facial area were examined using a visual analog scale of pain, the clinical Helkimo index and spiral computed tomography. The method of measuring the bone channels and holes of the skull is described. Criteria for assessing the degree of asymmetry of bone structures are proposed. Conclusions. The factors of predisposition to prosopalgia of dental patients in the presence of narrowing and pronounced asymmetry of the size of the bone canals of the skull were revealed.

Optic disc drusen and scleral canal size - protocol for a systematic review and meta-analysis.

Around one in forty patients are diagnosed with optic disc drusen (ODD) during their lifetime. Complications of these acellular deposits range from asymptomatic visual field deficits to artery occlusion and subsequent cecity. Still, the pathogenesis of their emergence remains controversial. In particular, it was suggested 50 years ago that a narrow disc and scleral canal is one factor leading to axoplasmic flow disturbance, which induces ODD formation. However, this hypothesis is still debated today. To evaluate the basis of this theory, we will conduct a systematic review and meta-analysis of studies evaluating the scleral canal size in patients with ODD and in healthy subjects. We will search MEDLINE via PubMed, Cochrane, and EMBASE electronic databases to identify articles published before November 29, 2022 that measure the scleral canal size in patients with ODD and in healthy subjects. In addition, grey literature will be searched. The meta-analysis will include studies that include patients with a clinical or imaging diagnosis of ODD and healthy subjects. Additionally, we will perform a subgroup analysis to compare patients with buried ODD and patients with visible ODD. Extracted data from included studies will be presented descriptively, and effect sizes will be computed based on the recommendations from the Cochrane Collaboration handbook. The hypothesis that a narrow scleral canal is a risk factor of ODD has long been debated and this systematic review and meta-analysis should disentangle the different views. Understanding the underlying factors driving the development of ODD should help us focus on patients at risk and develop strategies to prevent advanced stages of the disease in these patients. Besides, focusing on patients with small scleral canals should help us derive associated factors and provide a better understanding of the pathology. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022375110.

The difference distance between the apical foramen and the anatomical apex in primary teeth-An in vitro study.

The apex area in the primary teeth changes continuously due to the physiologic resorption, therefore; the apical foramen (AF) may not correspond to the anatomic apex (AA), which gives a big challenge to achieve successful endodontic treatment. The aim of this research was to study the difference distance (DD) between the position of the AA and AF, besides the difference acceptance (DA) in primary teeth, and the effect of the following variables: root canal curvature, resorption degree, and canal size on DD and DA separately. In this research, 180 root canals from 60 primary teeth were studied. Two lengths of each canal were measured by a K-file from a certain point in the crown; the first length was until the AA and the second was until the AF. Then DD was obtained by calculating the difference between those two lengths. Statistical analysis tests were done. A p value of <.05 was considered significant at a 95% confidence level. The percentage of canals with 0 mm DD was 34.4%, while it was 1.1% with DD of 6 mm. The percentages of acceptable ( ≤ 2 mm) and unacceptable ( > 2 mm) difference were 84.4% and 15.6%, respectively. There was a significant difference in the DD value between the three groups of curvature degree and the three groups of canal size. There was a significant difference between the DA in the three groups of canal size. DD has a wide variation value in primary teeth regardless of the degree of root resorption, which has not affected this value or the accepted difference; however, DD and acceptable difference values are somehow affected by the degree of root curvature and canal size. We recommend adding acceptable difference as a criterion when considering pulpectomy treatment in primary teeth.

Dual Parallel Intramedullary K-Wires for Arthrodesis of the Finger Distal or Thumb Interphalangeal Joints.

K-wire arthrodesis methods are commonly used during arthrodesis of the finger distal interphalangeal (DIP) or thumb interphalangeal (IP) joints. Here we propose an advantageous approach involving dual parallel intramedullary K-wires with the K-wire tips cut to bury underneath the skin. From January 2017 to December 2021, 35 patients (43 joints) underwent finger DIP or thumb IP joint arthrodesis using this method. Radiographic outcomes were evaluated, while functional outcomes were assessed using the visual analogue scale (VAS) for pain and the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score. Patients with at least 1 year follow-up were analyzed. The preoperative and postoperative functional results were analyzed using the paired t-test. Arthrodesis union was achieved in 41/43 joints (95.3%). We treated 10 thumb IP joints and 33 finger DIP joints, for which the underlying cause was osteoarthritis and trauma in 37 and six digits, respectively. The average time of K-wire removal was 8.9 (range, 7-10) weeks after surgery. Twenty-four patients (27 joints; 22 women, two men) had at least 1 year follow-up (mean 15.9; range, 12.5-40.8) months. For patients with bone healing, the VAS score improved from 6.6 (range, 5-8) to 0.6 (range, 0-1) (p < 0.001), and the QuickDASH score improved from 57.9 (range, 31.8-77.3) to 14.7 (range, 6.8-20.5) (p < 0.001) at final follow-up. Both of the two failure cases were in the thumb. There were no other complications. This technique is simple and cost-effective and achieves a good union rate. The advantages include the ability to choose variable K-wire sizes according to the size of the medullary canal and the ease of postoperative care.

Pathological Study of Light Cupula Syndrome on a Visual Bionic Semicircular Canal.

A type of persistent direction-changing positional nystagmus with a null point during head position deflection is known as light cupula syndrome (LCS) in the clinic. To date, the pathogenesis and biomechanical response of human semicircular canals with light cupula syndrome (LCS) (HSCs-LCS) are still unclear. In this study, based on the anatomical structure and size of the one-dimensional human semicircular canal (HSC) and imitating the pathological changes of the endolymph in HSC with LCS, a visual bionic semicircular canal (BSC) with LCS was fabricated using three-dimensional printing technology, hydrogel modification, and target tracking technology. Through theoretical derivation, mathematical models of the HSC-LCS perception process were established. By conducting in vitro experiments on the bionic model, the biomechanical response process of HSC-LCS was studied, and the mathematical models were validated. The results of pulse acceleration stimulation showed that the pathological changes in the density and viscosity of the endolymph could reduce the deformation of the cupula of the BSC-LCS and increase the time constant. The results of the sinusoidal acceleration stimulation showed that the amplitude-frequency gain of the BSC-LCS decreased and the phase difference increased. The BSC-LCS can be used as a tool for pathological research of the HSC-LCS. The results of this study can provide a theoretical basis for clinical diagnosis.

A shape memory alloy implant can be an effective surgical treatment in the atlantoaxial joint stabilization using rabbits as substitutes for toy-breed dogs.

To investigate the feasibility of using shape memory alloy (SMA) implants for atlantoaxial joint stabilization using a rabbit model as a substitute for canines. 20 rabbit cadavers. We prepared rabbit cadavers from the middle of the skull to the third cervical vertebra. The vertebral body and canal sizes of the atlas and axis were compared using CT data from rabbits, normal dogs, and dogs with atlantoaxial instability (AAI) to assess the feasibility of using rabbits as substitutes for toy-breed dogs. The shape memory alloy (SMA) implants were designed to stabilize the atlantoaxial joint without compromising the spinal canal passage for safety and were classified into SMA-1 and SMA-2 based on their design. To evaluate the strength, the ventrodorsal force was measured with atlantoaxial ligaments intact, after removing the ligaments, and after applying conventional wire or SMA implants to stabilize the atlantoaxial joint. The time taken for implant application was measured. No significant difference in vertebral body size of the atlas and axis was observed. A significant difference in vertebral canal size was observed between the animals. In biomechanical testing, the SMA-2 implant provided more stabilization, while the SMA-1 implant had lower strength than the conventional method using wires. The application time of wire was the longest, while that of SMA-1 was the shortest. SMA implants provide comparable strength and demonstrate superior efficacy compared to conventional dorsal wire fixation of atlantoaxial stabilization. Therefore, SMA implants can be an effective surgical option for AAI.

Quantitative Assessment of Dimensional Evaluation and Artefacts from Filling Materials with CBCT Using Standard Phantom Roots.

To investigate the accuracy of dimensional evaluation and representation of artefacts generated by different gutta-percha (GP) cones with or without sealer with CBCT using a reproducible, standardised phantom root methodology. The reproducible artificial phantom roots with six root canal sizes from #25 to #50 and 0.04 taper were aligned according to the jaw curvature in a stone model for dimensional measurements. Each root was scanned while empty and filled with four types of filling materials. The specimens were scanned using the CS 9300 3D (Carestream Dental, Rochester, NY, USA) (at two different resolutions), 3D Accuitomo (J Morita, Kyoto, Japan) and NewTom VGi (Verona, Italy) CBCT systems. The hyperdense and hypodense axial slice artefacts from root canal sizes #40, #45 and #50 were recorded. Dimensions were significantly smaller and more accurate with CS 9300/0.09 mm voxel size than with other protocols. The hypodense band was found mostly in the CS 9300 3D system with 0.18 mm voxel size, especially in the buccal-lingual (95%) and coronal (64%) sections. The 3D Accuitomo CBCT system showed the lowest presence of the hypodense band. Areas of both light and dark artefacts were significantly larger in the coronal third than in the apical and middle thirds. Artefacts in the coronal locations and in buccal-lingual sections were more evident in the CS 9300 3D system with a 0.18-mm voxel size.

Functional Outcome of Pediatric Subtrochanteric Fractures Treated With a Titanium Elastic Nailing System (TENS) Versus Plating.

Introduction Uncertainty exists regarding the ideal course of therapy for subtrochanteric fractures in children of intermediate age. These fractures arechallenging to treat, with scarce literature-based evidence to support a definitive implant. The ideal course of treatment should consider the patient's weight, age, femoral canal size, associated injuries, fracture stability, and surgeon's experience. A subtrochanteric femoral fracture in a child between the age of 5-12 is difficult to treat. For these patients, there is debate concerning the optimal internal fixation, hence this study was conducted to try and determine the superior mode of treatment for these fractures. The objective of this study is to compare functional outcomes of subtrochanteric fractures in the paediatric age group operated on with titanium elastic nail and plate fixation and the complications associated with both treatment modalities. Materials and methods Thisis a retrospective observational study of 40 cases that were admitted and operated on in the hospital of the current study from May 2007 to November 2021. Twenty patients underwent titanium elastic nailing system (TENS)nailing and the other 20 patients underwent plating for subtrochanteric fractures. The surgeries were conducted at our institute and patients were followed up at one-, three-, and six-month intervals. The final functional results were calculated with the help of the Flynn scoring system. Results Out of 40 patients involved in the present study, 17 were female while 23 were male. Twenty patients received treatment with titanium elastic nails, and the remaining twenty received plating. The majority of the patients were males around 9.6 years of age on average in the plating group and 8.9 years in the nailing group. In comparison to 75% of participants in the plating group, 40% of patients who received nailing showed excellent results. Results were satisfactory for five patients who received titanium elastic nails and one who received plating. The only poor outcomes were noticed in six people (30%) in TENS and three people (15%) in the plating group who went through unplanned surgery for complications. In comparison to the plating group, the overall rate of complication was much greater in the TENS group. Conclusion We would like to conclude our study that, in accordance with Flynn's score, both elastic nailing and plating stabilization can produce positive functional outcomes. Both groups have a similar percentage of excellent and good results.We also conclude that the overall complication rate is slightly higher for patients treated with TENSwhen compared to plating for subtrochanteric fractures.

Patterns of stress distribution of endodontically treated molar under different types of loading using finite element models—the exploring of mechanism of vertical root fracture

IntroductionThe purpose of this study was to explore the mechanism of vertical root fracture (VRF) using three-dimensional finite element models (FEMs). MethodsAn endodontically treated mandibular first molar with a subtle VRF was collected and scanned with cone beam CT (CBCT). Three finite element analysis models were created: Model 1 had the actual endodontically treated root canal size; Model 2 had the same root canal size as the contralateral homonymous tooth; and Model 3 had the root canal size expanded by 1 mm based on Model 1. Different types of loading were performed on these 3 FEMs. The stress distribution on the cervical, middle, and apical planes was analyzed, and the maximum stress on the root canal wall was calculated and compared. ResultsIn Model 1, the maximum stress around the root canal wall occurred in the cervical part of the mesial root under vertical masticatory force and in the middle part of the mesial root under buccal and lingual lateral masticatory forces. Additionally, there was a stress change zone in a bucco-lingual direction that corresponded with the actual fracture line. In Model 2, the maximum stress around the root canal was in the cervical part of the mesial root under both vertical and buccal lateral masticatory forces. For Model 3, the stress distribution was similar to that of Model 1, but greater under buccal lateral masticatory force and occlusal trauma force. In all three models, the maximum stress around the root canal wall was in the middle part of the distal root under occlusal trauma force. ConclusionsThe uneven stress around the root canal in the middle part (presented as a stress change zone in a bucco-lingual direction) may be the cause of VRFs.

Mechanics of removing water from the ear canal: Rayleigh–Taylor instability

Water stuck in the ear is a common problem during showering, swimming or other water activities. Having water trapped in the ear canal for a long time can lead to ear infections and possibly result in hearing loss. A common strategy for emptying water from the ear canal is to shake the head, where high acceleration helps remove the water. In this present study, we rationalize the underlying mechanism of water ejection/removal from the ear canal by performing experiments and developing a stability theory. From the experiments, we measure the critical acceleration to remove the trapped water inside different sizes of canals. Our theoretical model, modified from the Rayleigh–Taylor instability, can explain the critical acceleration observed in experiments, which strongly depends on the radius of the ear canal. The resulting critical acceleration tends to increase, especially in smaller ear canals, which indicates that shaking heads for water removal can be more laborious and potentially threatening to children due to their small size of the ear canal compared with adults.

The Mouthparts of Female Blood-Feeding Frog-Biting Midges (Corethrellidae, Diptera)

Females of frog-biting midges (Corethrellidae) obtain their blood meals from male calling frogs. While the morphology of the feeding apparatus is well studied in hematophagous Diptera that impact humans, frog-biting midges have received far less attention. We provide a detailed micromorphological examination of the piercing blood-sucking proboscis and maxillary palpus in three Corethrella species using scanning electron microscopy and histological semi-thin sectioning. We also compare the sensilla found on the proboscis tip and the palpus of Corethrella with other piercing blood-sucking Diptera. Corethrella spp. have a proboscis length of about 135 µm, equipped with delicate mandibular piercing structures composing the food canal together with the labrum and hypopharynx. Their proboscis composition is plesiomorphic and more similar to other short-proboscid hematophagous Culicomorpha (e.g., Simuliidae), in contrast to the phylogenetically more closely related long-proboscid Culicidae. As in other short-proboscid taxa, the salivary canal in Corethrella spp. transitions into an open salivary groove with one mandible forming a seal, whereas in Culicidae the salivary canal is closed until the tip of the proboscis. We discuss the possible functional constraints of very short, piercing blood-sucking proboscises (e.g., dimensions of host blood cells) that may limit the size of the food canal.

Resin Canal Traits Variation in Pinus spp. with Different Susceptibility to the Pine Wood Nematode

Different studies have emphasized the influence of resin canal traits in the susceptibility of pine trees to the pine wood nematode (PWN) Bursaphelenchus xylophilus. Resin canals can facilitate the PWN migration through the stem and are involved in the accumulation of volatile terpenes in the xylem in response to the pathogen, inducing tracheid embolisms. In this work, we conducted a PWN inoculation experiment under greenhouse conditions to investigate the anatomical traits of constitutive resin canals among seven Pinus species with different degrees of susceptibility to the PWN: P. canariensis, P. halepensis, P. pinea and P. taeda were grouped into a ‘low-susceptible group’, and P. pinaster, P. radiata, and P. sylvestris were grouped into a ‘high-susceptible group’. The high-susceptible group presented higher xylem radial growth, wider constitutive canals in the cortex, lower frequency of constitutive canals in the cortex, and smaller constitutive canals in the xylem than the low-susceptible group. The size of constitutive cortical canals was positively related to the number of seedlings colonized by the PWN, suggesting that wider canals facilitated migration. The inoculation of the PWN increased the frequency and diminished the mean area of canals in the xylem, and the high-susceptible group showed more frequency of induced xylem canals than the low-susceptible group. Additionally, the high-susceptible group presented larger radial growths in the xylem than the low-susceptible group. These results suggest a role of resin canal traits on Pinus spp. susceptibility to the PWN. Nevertheless, the high interspecific variability found in these traits within each susceptibility group evidences the importance of other factors in the susceptibility to the PWN.

Semicircular canal shape diversity among modern lepidosaurs: life habit, size, allometry

BackgroundThe shape of the semicircular canals of the inner ear of living squamate reptiles has been used to infer phylogenetic relationships, body size, and life habits. Often these inferences are made without controlling for the effects of the other ones. Here we examine the semicircular canals of 94 species of extant limbed lepidosaurs using three-dimensional landmark-based geometric morphometrics, and analyze them in phylogenetic context to evaluate the relative contributions of life habit, size, and phylogeny on canal shape.ResultsLife habit is not a strong predictor of semicircular canal shape across this broad sample. Instead, phylogeny plays a major role in predicting shape, with strong phylogenetic signal in shape as well as size. Allometry has a limited role in canal shape, but inner ear size and body mass are strongly correlated.ConclusionsOur wide sampling across limbed squamates suggests that semicircular canal shape and size are predominantly a factor of phylogenetic relatedness. Given the small proportion of variance in semicircular canal shape explained by life habit, it is unlikely that unknown life habit could be deduced from semicircular canal shape alone. Overall, semicircular canal size is a good estimator of body length and even better for body mass in limbed squamates. Semiaquatic taxa tend to be larger and heavier than non-aquatic taxa, but once body size and phylogeny are accounted for, they are hard to distinguish from their non-aquatic relatives based on bony labyrinth shape and morphology.

The correlation between lumbar interlaminar space size on plain radiograph and spinal stenosis.

Investigating the correlation between the interlaminar space size on plain radiograph and lumbar spinal stenosis (LSS). 100 Patients with LSS and 100 normal participants without LSS were included in this study. Lumbar interlaminar parameters were measured on plain radiographs. Spinal canal parameters were measure on CT and MRI. These image parameters were compared between LSS and control group. The linear correlation among interlaminar parameters, spinal canal parameters and Oswestry Disability Index (ODI) were analyzed. The cut-off values of interlaminar parameters for diagnosing L3/4 and L4/5 symptomatic LSS were analyzed. Excepting for L1/2 interlaminar width, all interlaminar and spinal canal related parameters in LSS group were significantly smaller than those in control group. Excepting for L1/2 interlaminar width and L5/S1 interlaminar height, all interlaminar parameters had significantly positive linear correlation with spinal canal parameters accordingly in each lumbar level. For diagnosis of symptomatic LSS, The cut off values of L4/5 interlaminar width, height and area were 18.46mm, 11.37mm and 134.05mm2 while 15.78mm, 13.59mm and 157.98mm2 in L3/4. Both spinal canal size and interlaminar size had no linear correlation with ODI in cases of L4/5 LSS. Lumbar interlaminar space size on plain radiograph has positive linear correlation with developmental and degenerative LSS, excepting for L1/2 interlaminar width and L5/S1 interlaminar height. Lumbar plain radiograph can be a feasible way for predicting and helping to diagnose LSS through evaluating the interlaminar space size. III.

Morphometric and morphological evaluation of the optic canal in three different parts in MDCT images.

This study aimed to classify the morphometry and variations of optic canal by examining its changes according to gender and body side, and developments according to age. We retrospectively evaluated the orbit and paranasal sinus computerized tomography images of 200 individuals (age range 3months-90years;106 female, 94 male). In this study, three different parts of optic canal in evaluated morphometric and morphological. The intracranial aperture was found to be statistically significantly wide in males than females on both sides (p˂0.05). When optic canal types were evaluated, the most common type among healthy individuals was conical type (right: 68%, left:67.5%), and the least common type was irregular type (right and left:1.5%). According to the type of optic waist, the most common was triangle type. Considering the possible effect of optic canal size on pathologies, it is important to establish a basis for the parameters of this structure in healthy individuals. In this study, both the morphology and morphometry of the canal as well as variations were examined and it was determined that the structure was affected by gender, body side and age group. Knowledge of anatomic morphometry, variations and complexities arising from these are important for clinical diagnosis and management.

Врожденная односторонняя аномалия развития наружного слухового прохода

The main types of congenital pathology of the external and middle ear are microtia and atresia/stenosis of the external auditory canal. However, isolated cases of atresia/stenosis of the external auditory canal in combination with normal size and shape of the ear canal are quite rare. The article describes a clinical case of a child during the first year of life with congenital stenosis of the external auditory canal in combination with an anomaly of the development of the auditory ossicles, which was observed for 6 months. The results of extended audiological examination showed an increase in the hearing threshold on the left due to conductive hearing loss. In the case of the patient described in the article, a decision was made to use a wait-and-see approach for the child: dynamic observation by a deafness specialist otolaryngologist no less than once every 6 months.

Normal Cone beam Computed Tomography image findings of nutrient canals in 340 pediatrics

The purpose of this study was to assess normal image findings of mandibular nutrient canals(NCs) using CBCT images, including canal prevalence, number, size of nutrient canal. 340 consecutive pediatric patients were included in this study. Parameters including canal prevalence, number and size (mesial-distal and buccal-lingual diameters) were measured on CBCT axial images. 82.1% were found NCs in the anterior region of the mandible. The mean number of NCs were 1.39 in males and 1.49 in females. However, there were no significant age and gender-related differences in the mean number of NCs. The mean diameter of NCs were approximately 0.6mm in both males and females. However, there was no significant age related differences in the size of NCs in both males and females. In conclusion, this was the first study that described normal CBCT findings of mandibular anterior NCs in pediatrics. The prevalence of accidents or lesions in anterior mandible is low, by preoperative knowledge of the NCs in anterior region of the mandible, complications such as injury to the NCs can be avoided in pediatrics.