Canal Depth Research Articles

New gutta percha composite with high thermal conductivity and low shear viscosity contributed by the bridging fillers containing ZnO and CNTs

Gutta percha (GP) point is typically used as the filling material during the root canal therapy, as its malleable, inert, and biocompatible properties. However, due to its low thermal conductivity (TC) and high shear viscosity, the vimineous GP point is difficult to melt and to flow into the root canal. In this study, a new GP composite with high TC and low shear viscosity is prepared by mixing a large amount of zinc oxide (ZnO) fillers bridged by a small quantity of carbon nanotubes (CNTs) (GP/ZnO@CNTs). Compared with the GP composite filled by ZnO alone (450phr), the TC of GP composite increases by 75.6% with 400phr ZnO and 50phr CNTs. Moreover, the TC and shear viscosity of GP composite containing 400phr ZnO and 20phr CNTs are 9.3% more and 4.5% less than those of a common commercial GP point (Bio-gutta percha (BP) point), respectively. The in vitro experiments confirm that the GP/ZnO@CNTs possesses the large filling depth of lateral canal, which is 9.0% longer than that of BP point at position WL-3. The cytotoxicity of the new GP composite extracts is grade 0–1, indicating that the material is qualified to prepare the GP point.

3D-Modelling of Charlemagne’s Summit Canal (Southern Germany)—Merging Remote Sensing and Geoarchaeological Subsurface Data

The Early Medieval Fossa Carolina is the first hydro-engineering construction that bridges the Central European Watershed. The canal was built in 792/793 AD on order of Charlemagne and should connect the drainage systems of the Rhine-Main catchment and the Danube catchment. In this study, we show for the first time, the integration of Airborne LiDAR (Light Detection and Ranging) and geoarchaeological subsurface datasets with the aim to create a 3D-model of Charlemagne’s summit canal. We used a purged Digital Terrain Model that reflects the pre-modern topography. The geometries of buried canal cross-sections are derived from three archaeological excavations and four high-resolution direct push sensing transects. By means of extensive core data, we interpolate the trench bottom and adjacent edges along the entire canal course. As a result, we are able to create a 3D-model that reflects the maximum construction depth of the Carolingian canal and calculate an excavation volume of approx. 297,000 m3. Additionally, we compute the volume of the present dam remnants by Airborne LiDAR data. Surprisingly, the volume of the dam remnants reveals only 120,000 m3 and is much smaller than the computed Carolingian excavation volume. The difference reflects the erosion and anthropogenic overprint since the 8th century AD.

Reappraising the neurosurgical significance of the pterion location, morphology, and its relationship to optic canal and sphenoid ridge and neurosurgical implications.

Frontolateral craniotomy procedures have advanced from conventional craniotomy to mini-craniotomy, and to contemporary keyhole surgery. In this context, it is important for the neurosurgeon to precisely locate the pterion. The distance of the pterion center from midpoint of zygomatic arch and posterolateral margin of frontozygomatic suture was studied bilaterally in 50 whole adult skulls in Indian ethnic group. The depth of optic canal and sphenoid ridge from the pterion was recorded bilaterally in fifty cut adult skulls and fifteen three-dimensional computed tomography scans. The suture length, thickness, and morphology were studied. The data were analyzed using SPSS software, two-tailed Student's t test, binary logistic regression and receiver operating characteristic curve for sexual dimorphism. The pterion center was located at a mean distance of 37.02 mm above the midpoint of zygomatic arch, 28.20 mm behind the posterolateral margin of frontozygomatic suture, 42.73 mm lateral to the optic canal and 10.59 mm from the sphenoid ridge. The location did not exhibit sexual dimorphism. In 20% cases the pterion center was 40 mm or more above the midpoint of the zygomatic arch and in 5% cases 35 mm or more posterior to the posterolateral margin of frontozygomatic suture. The mean suture length was 10±3 mm. The mean thickness at the center of the pterion was 3.52±1.45 mm. The commonest variety was sphenoparietal followed by frontotemporal, epipteric, and stellate types. A thorough knowledge of these dimensions has innumerable neurosurgical implications in resection of sellar, parasellar, and paraclinoid tumors and circulatory aneurysms.

Effect of Resin Cement Mixing and Insertion Method into the Root Canal on Cement Porosity and Fiberglass Post Bond Strength.

To evaluate the method of resin cement mixing and insertion into the root canal on resin cement porosity and fiberglass-post push-out bond strength (PBS). One hundred twenty human single-rooted teeth were sectioned to a length of 15 mm, en-do-dontically filled, and received a fiberglass post cemented with 3 self-adhesive resin cements (RelyX U200, seT, Panavia SA) using 4 mixing methods/insertion techniques (handmix/endodontic file, handmix/Centrix syringe, automix/conventional tip, automix/endo tip). The samples were scanned using micro-CT. Two slices from the cervical, middle, and apical thirds were submitted to push-out bond strength (PBS) testing, and failure modes were classified. The PBS, volume of resin cement, and porosity data were analyzed using ANOVA and Tukey's test. The porosity was lowest in the cervical third and highest in the apical third, irrespective of the resin cement. The porosity was lower in the the automix/endo tip group compared to the handmix/endodontic file group. The use of Centrix or endo tip reduced the porosity and increased the PBS in the apical third compared with the use of endodontic files. The root canal depth reduced the PBS for U200 and seT when handmix/endodontic files were used. U200 and seT using the automix method increased the PBS, thus eliminating the effect of root region, irrespective of the insertion technique. In general, U200 showed higher PBS and Panavia lower PBS. Adhesive failure between root dentin and resin cement was predominant. Automixing the cement and using an endo tip produces fewer voids and increased the bond strengths.

Sexuality after Male-to-Female Gender Affirmation Surgery.

Male-to-Female (MtF) gender affirmation surgery (GAS) comprises the creation of a functional and aesthetic perineogenital complex. This study aimed to evaluate the effect of GAS on sexuality. We retrospectively surveyed all 254 MtF transsexual patients who had undergone GAS with penile inversion vaginoplasty at the Department of Urology, University Hospital Essen, Germany, between 2004 and 2010. In total, we received 119 completed questionnaires after a median of 5.05 years since surgery. Of the study participants, 33.7% reported a heterosexual, 37.6% a lesbian, and 22.8% a bisexual orientation related to the self-perceived gender. Of those who had sexual intercourse, 55.8% rated their orgasms to be more intensive than before, with 20.8% who felt no difference. Most patients were satisfied with the sensitivity of the neoclitoris (73.9%) and with the depth of the neovaginal canal (67.1%). The self-estimated pleasure of sexual activity correlated significantly with neoclitoral sensitivity but not with neovaginal depth. There was a significant correlation between the ease with which patients were able to become sexually aroused and their ability to achieve orgasms. In conclusion, orgasms after surgery were experienced more intensely than before in the majority of women in our cohort and neoclitoral sensitivity seems to contribute to enjoyment of sexual activity to a greater extent than neovaginal depth.

Effect of silane-containing universal adhesive on push-out bond strength of glass fiber post to composite resin and to resin cement/intraradicular dentin

This in vitro study aimed at evaluating the effect of glass-fiber post (GFP) surface treatment with a silane-containing universal adhesive and/or a silane coupling agent on push-out bond strength to dual cure resin cement/dentin (Experiment 1) and to resin composite (Experiment 2). Methods: For Experiment 1, sixty human premolar root canals were prepared to receive GFP cementation. Then an adhesive system was applied, according to the manufacturer's instructions. The GFPs (Reforpost no. 2, Angelus) were randomly divided into 2 groups, according to application or non-application of a silane coupling agent for 60 seconds (Prosil, FGM). Each group was further divided into 3 groups, according to the adhesive system to be applied to the GFP surface (n = 10): 1. SBU - silane-containing universal adhesive (Adper Single Bond Universal Adhesive, 3M ESPE); 2. ASB2 – etch-and-rinse adhesive system not containing silane in its composition (Adper Single Bond 2, 3M ESPE); 3. CG (control group) – no treatment. Cementation of GFPs to intraradicular dentin was performed with dual-cure conventional resin cement (Rely X ARC/ 3M ESPE). After 48 h, the roots were cross-sectioned at three different depths, resulting in serial slices corresponding to the cervical, middle and apical root thirds. For Experiment 2, surface-treated GFPs (n=10) were centered in a plastic matrix in which the resin composite (Filtek Z250 XT, 3M ESPE) was incrementally inserted and light-cured. Slices were obtained, as in Experiment 1. Push-out bond strength testing was performed on a universal machine (0.5 mm/min crosshead speed). Results: In Experiment 1, three-way ANOVA (α = 0.05) indicated that the bond strength of GFP to resin cement/intraradicular dentin was not affected by use or nonuse of a silane coupling agent, by application or non-application of an adhesive layer or by the root canal depth (p > 0.05). For Experiment 2, two-way ANOVA and Tukey's test showed that when the GFP received silane pretreatment, bond strength to resin composite was not affected by the application of an adhesive layer to the post. However, when the post was not pretreated with silane, the bond strength was higher for the universal adhesive (p = 0.021). The bond strength to post/resin cement/dentin was unaffected by post silanization or by the application of an adhesive system layer on the post. Bond strength of the post to resin composite was unaffected by adhesive system application, if the post was previously treated with a silane agent. In the absent of post silanization, a universal adhesive containing silane achieved higher bond strength of the post to resin composite.

Resection of an Optic Canal Meningioma through a Contralateral Subfrontal Approach with Endoscopic Assistance: A 2D Operative Video.

Objective To review the use of the contralateral subfrontal approach for the resection of an optic canal meningioma. Design Operative video. Results A meningioma, located in the inferomedial side of the optic canal ( Fig. 1 ), was found to cause significant visual deterioration. The subfrontal route was preferred to expose the tumor without mobilization of the optic nerve. Drilling of the anterior limb of the chiasmatic sulcus (limbus sphenoidale) provided adequate exposure of the medial aspect of the optic canal. Gross total resection (Simpson II) of the tumor was accomplished, and endoscopic assistance allowed identification and coagulation of an infiltrated dura mater in the chiasmatic sulcus and tuberculum sellae. Conclusion The subfrontal approach grants an optimal surgical trajectory to the contralateral chiasmatic sulcus and optic nerve. When the medial side of the optic canal is drilled, tumors extending into the optic canal can be safely resected, under direct visualization of the inferomedial side of the optic nerve. Breach into the sphenoid sinus can occur during drilling of the anterior limb of the chiasmatic sulcus. Endoscopic assistance can provide a better view on blind areas of the surgical field, including the depth of the optic canal ( Fig. 2 ). The link to the video can be found at: https://youtu.be/fS2udUCPH1g .

An analysis of proximal humerus morphology with special interest in stemless shoulder arthroplasty

Shoulder arthroplasty evolution has resulted in the shortening of traditional stemmed humeral components. Newer stemless implants rely on structures that maintain fixation in the metaphyseal region of the proximal humerus. Whereas the overall morphology of the proximal humerus is well understood, the advent of stemless implants requires that additional geometric measures be assessed. This study's purpose was to introduce new anatomic measures to assist with the design of stemless implants. Using computed tomography data from 98 subjects (nonarthritic [n = 41], B2 osteoarthritic [n = 26], and symmetric osteoarthritic [n = 31]), shifts in proximal canal direction, bounding diameters along the canal, and canal depth beneath the center of the humeral resection plane were quantified. Traditional articular aspect ratio terms (ie, resection diameter, humeral head height) were also quantified. All measures were reported relative to a humeral coordinate system relevant to stemless implants. Humeral depth, gender, and osteoarthritis were found to have effects on the measured parameters. Of these factors, gender was the most prominent, as men presented with significantly larger canal diameters and depths than women did (P < .001). Osteoarthritis had less of a significant impact on results (P < .001), with the attributed differences in canal path direction and articular aspect ratio being small in absolute value. Canal diameter was found to change significantly as a function of depth beneath the resection plane (P < .001). This work quantified 3 new morphologic terms relevant to proximal humerus stemless arthroplasty. Together, these outcome measures help define the spatial limits for stemless humeral arthroplasty in an implant-relevant coordinate system.

Evaluation of field layout for the cultivation of other field cropsin bayawa minor irrigation systemin Sri Lanka

Minor irrigation systems are very unique to Sri Lankan agriculture for centuries for its role in food security, livelihood and ecosystem sustainability. The objective of this study was to evaluate constraints and potentials of paddy field system layout in a minor irrigation system for other field crop (OFC) cultivation. The study was done in Bayawa minor irrigation system, in Sri Lanka during 2014 and 2015. Data were collected and analyzed to evaluate, system components and their sustainability, canal uniformity, accessibility, and land and farmer plots distribution in the command area. Results according to the system layout reveal that, irrigation canals’ uniformity varies along with the distance from head to tail endswith a water conveyance efficiency of 60%. Canal depth increases mainly due to sand mining, thus,requires a large amount of irrigation water for maintaining a hydraulic head in canals in order to supply irrigation water to fields under gravity. Positive hydraulic head of the right canal up to 70% of its length facilitates water distribution from canal to fields, but negative hydraulic head of the left canal constrains for that. As of the system layout and canal distribution, plot to plot irrigation is the common practice in the command area. The number of plots vary from 2-19 with the highest frequency of 6 plots. Cultivation of OFCrequires individual access to water to each plot. Hence, this irrigation and drainage system restrict OFC cultivation. Furthermore, 56% farmers hold less than 0.4 ha farmer fields due to land fragmentation over the years. This also leads to, low accessibility of individual field plots to irrigation canal and identified as major constraint to OFCcultivation.

Anatomy research of cervical laminoplasty with preservation of the posterior ligament complex.

Objective: To evaluate the feasibility of cervical laminoplasty with preservation of the posterior ligament complex for enlarging the spinal canal. Methods: Six up-to-standard human corpse specimens were divided into two groups by simple randomization (start from C4 group, S4; start from C5 group, S5; 3 corpses in each group). Decompression operation of C3-C6 level was performed in a predetermined sequence by using the new procedure with preservation of the posterior ligament complex.The basic depth of spinal canal was measured with a depth gauge at fixed point after the right bone groove of single level was completed.The operation of the contralateral bone groove was continued, and then the spinal canal was measured again when the spinous process was pulled backward by using a tissue forceps until the ligament complex was just tight.Retreat value (RV) of vertebral lamina was obtained by calculating the difference between the two measurements.The earlier measured levels needed to be remeasured when the operation area increased by one level. Two independent sample and one-sample t test were used to analyze the measurement results. Results: RV of vertebral lamina was small after finishing the first level of the decompression operation [S4: (0.87±0.72) mm; S5: (1.83±0.29) mm], and the value reached its maximum after the completion of C3-C6 level.The overall average RVmaxs from C3 to C6 level were (2.37±0.52) mm, (4.27±0.78) mm, (3.73±0.93) mm and (2.16±0.77) mm, respectively.The overall average retreat rates (RR) were 17%±7%, 32%±9%, 29%±10% and 16%±6%, respectively. The overall average RVmax of C4 and C5 level reached or exceeded the decompression threshold value of 4 mm (t=0.839, -0.703, both P>0.05). The average RVmax of C4/C5 level was similar in the two groups (t=-1.204, 1.189, both P>0.05); however, the difference of average RVmax between C3 and C6 level was significant (t=-4.429, 4.196, both P<0.05). Conclusions: Cervical laminoplasty with preservation of the posterior ligament complex can enlarge the sagittal diameter of spinal canal and relieve the compression of spinal cord.In addition, RV of each level increases as the number of the operation level increases, and the ability of vertebral lamina to retreat is quite different from C3 to C6 level.The decompression effect in the middle of the operation area is better than that on the cranial and tail side.

Classification Proposal to measure extension defects of endodontically treated anterior teeth

Summary: A classification of the extension defects ofendodontically anterior teeth is presented. This classification is based on the amount of remanentcoronal tooth after an essential treatment has been done, such as: root canal therapy, removal ofcarious tissue, periodontal surgery whenever needed and tooth preparation either for the placementof a direct restoration material such as composite or a post and core and full crown restoration.This classification is based on 3 specific variables: supragingival remaining coronal toothstructure or core height, diameter and root canal depth. Key words: Post and core. Root canaltreatment. Diagnostic.

Morphometric Analysis of Human Second Cervical Vertebrae (Axis)

Possessing an odontoid process and unique superior articular facets, the axis vertebra morphometry significantly differs from morphometry of other cervical vertebrae. The fractures of axis, especially its dens, are very common and surgeries highly risky. Knowledge of the axis dimensions is essential not only for preclinical studies, diagnosis of spinal cord diseases, planning of the surgeries but also for correct selection and insertion of surgical instruments or vertebral implants design. Many quantitative studies of the second cervical vertebra have been performed, yet still lacking the area parameters determination and precision of three-dimension in vivo measurement. Vertebral dimensions are reported to vary among populations, although there are very little studies examining Caucasian specimen. This study aims to provide three-dimensional in vivo morphometric analysis of the axis vertebra as well as comparison to the previous studies. The clinically relevant vertebral dimensions were measured on the threedimensional model reconstruction of CT scans providing high accuracy. Five human second cervical vertebrae were investigated (Caucasian males) and linear, area and angular dimensions were measured. The data on vertebral body dimensions were best fitting Doherty and Naderi measurement. The vertebra body anterior height was established to be 26.2 mm and the posterior height 21.4 mm. The dens parameters were similar to those presented by Doherty. Doherty also reported large variation in the dens sagittal angle which was observed in the present study as well. The dens height was determined to be 17.8 mm which is significantly greater compared to the previous studies. The smallest height among specimens was reported to be 17.0 mm. The smallest anteroposterior or transverse diameter of the dens measured was the upper depth, 9.4 mm. The smallest and biggest areas of dens were measured to be 79.0 mm2 and 121.6 mm2. The superior articular facet area with mean value 211.2 mm2 was observed to be significantly bigger than the inferior area, 141.2 mm2. The mean sagittal angle of the inferior facet area was assessed to be 42.1° and the mean frontal angle of the superior articular facet 69.3°. The parameters of articular facets measured by Xu correspond to the present study. Due to the vertebral body enlargement in the inferior part of vertebra, the spinal canal superior depth,18.0 mm, was observed to be bigger than its inferior depth, 16.2 mm. In case of the spinal canal depth, Sengul measured values considerably greater than other studies. However, Singla, Gosavi and Xu presented the parameters very similar to the present study. Spinal canal width was measured to be 24.4 mm supporting the measurement done by Sengul which is 24.7 mm. The measured vertebral dimensions can be used either for development of instrumentation, preclinical planning of surgeries, implant design or as the reference values for evaluation and diagnosis of various clinical conditions.

Calculation of the ultimate depth of a scour pit after debris flow through drainage canal ribs

Drainage canals are engineering structures widely used for debris flow mitigation. When passing through a drainage canal, debris flow usually scours the gully bed at the back of the rib sill of the drainage canal, which leads to failure of the rib sill. Therefore, the scour depth at the back of the rib sill is an important design problem and it is related to the economic benefits of engineering and service years. To explore the law of the depth of the scour pit after debris flow through drainage canal ribs, we first proposed a formula for the calculation of the maximum scour depth at the back of a rib sill based on energy conservation. We then conducted a series of simulation experiments to test the proposed formula. The experimental results show that the scour depth, trench slope and the distance between ribs all increase with a decrease in debris flow density. We then compared the results of experiments and formula calculations. Through the testing analysis, we found that the calculation results of the conducted formula correspond with the experimental results better. Finally, taking Qipan Gully as an example, we designed the ultimate depth of a drainage canal for debris flow using the calculation formula.

Undrained creep failure of a drainage canal slope stabilized with deep cement mixing columns

This paper presents an analysis of the slope failure of a Suvarnabhumi drainage canal during construction. The Suvarnabhumi drainage canal project includes a large drainage canal with a road on both sides. The width of the bottom of the drainage canal is 48.0 m, the depth of the drainage canal is 3.0 m, and the length of the drainage canal is 10.5 km. Because the project was constructed on very soft Bangkok clay, deep cement mixing (DCM) columns were employed to increase the stability of the excavated canal. The failure of the drainage canal slope occurred 25 days after the end of excavation. The field monitoring data show that lateral movement of the canal slope continuously increased with time, which caused failure due to the instability of the canal slope. The time-dependent deformation and undrained creep behavior of very soft clay was suspected to be the cause of the canal failure. A laboratory investigation of undrained creep behavior and a finite element analysis (FEA) using the soft soil creep (SSC) model were performed to confirm the causes of the canal failure. The results indicate that very soft clay specimens that are subjected to deviator creep stress levels of 70 and 100 % of the peak strength failed by creep rupture within 60 days and 8 min, respectively. The factor of safety for the canal slope, which was obtained from the FEA, shows significant reduction from the initial value of 1.710 to 1.045 within 24 days after the end of excavation due to the effect of undrained creep. This paper also describes a solution method that is applied to a new section of the canal. Field monitoring and an FEA of the new trial section were performed to prove the effectiveness of the solution method.

Single-coil magnetic induction tomographic three-dimensional imaging.

Previously, magnetic induction tomography (MIT) has been considered for noncontact imaging of human tissue electrical properties. Commonly, multiple coils are used, with any one serving as the source while others detect eddy currents generated in the specimen. Here, imaging of low conductivity objects is shown feasible with a single coil acting simultaneously as source and detector, provided that the coil is repeatedly relocated while collecting coil loss data. To enable such "scanning," an analytical coil loss formula is derived in the quasistatic limit for a single coil consisting of several concentric circular wire loops, all within a common plane. Conductivity may vary arbitrarily in space, whereas permittivity and permeability are treated as uniform. The analytical form is used to build an algorithm for imaging electrical conductivity in human tissues. A practical device operating at 12.5MHz is described and used in a clinical trial that "scans" the region between the scapulae while collecting coil loss data. Inversion of data leads to electrical conductivity distribution images for the thoracic spinal column which are the first of their kind to correctly distinguish such basic features as size and depth of spinal canal, as well as size, depth, and spacing of transverse spinal processes.

Sex determination based on the analysis of a contemporary Polish population's palatine bones: a computed tomography study of 1,200 patients.

The aims of the present study were to assess whether the hard palate reveals any measurable sex-related differences, and to create a mathematical model which would differentiate between males and females using hard palate measurements alone. The present study was conducted on 1,200 archived sinus computed tomography (CT) scans. Each cranial measurement was taken twice by the same observer, and in cases of any discrepancies, the mean of the two values was recorded. Twenty per cent of randomly chosen samples were re-measured by an observer who did not partake in assessing the samples the first time. Logistic regression was used to derivate two mathematical formulas which would calculate the probability of a skull being male. The studied group comprised 1,200 head CT's (627 female; 52.3%). The mean age of the group was 43.5 ± 17.4 years - no age difference between sexes was noted (p = 0.37). All of the performed measurements were significantly (p < 0.0001) larger in males than in females. The mathematical formula based on the "orale-spina nasalis posterior" (O-SNP) distance alone had a reliability rate of 68.35%. The equation based on the depth of the right greater palatine canal (GPC), the O-SNP distance and the anterior width of the palatal arch (AWPA) had a reliability rate of 78.37%. The most prominent sexually dimorphic parameters were the O-SNP, the GPC depth and the AWPA. The mathematical models presented in the current study can be used to successfully distinguish between sexes during forensic examination.

Assessment of factors affecting the difficulty of caudal epidural injections in adults using ultrasound.

In unaided caudal epidural block (CEB), incorrect needle insertion has been reported to occur in 15% to 38% of attempts. To statistically analyze the anatomical variables affecting difficult CEB using ultrasonographic measurement. Preprocedural ultrasonography was performed and the following measurements were obtained in 146 patients: the distance from the skin to the apex of the sacral hiatus; the depth of the sacral canal at the apex of the sacral hiatus; the length of the sacrococcygeal ligament between the apex of the sacral hiatus and sacral base; the distance from the skin to the apex of the sacral cornu; and the distance between the apexes of bilateral cornua. One clinician, unaware of the ultrasonographic findings, performed the injections using the landmark technique. The procedures were videotaped and were subsequently reviewed by an independent investigator. The means (± SDs) of the abovementioned measurements were 12.1±3.7 mm, 6.1±2.1 mm, 25.9±7.4 mm, 10.0±4.0 mm and 16.4±3.2&nbsp;mm, respectively. Injections failed in 16 (11%) patients and were defined as difficult in 21 (14.4%) patients. The depth of the sacral canal at the apex of sacral hiatus (P<0.001) and the length of the sacrococcygeal ligament between the apex of the sacral hiatus and sacral base (P=0.001) were significant predictors of difficult CEB. Of all patients, 85.7% and 75.2% were correctly classified as difficult or not difficult, respectively. The cutoff values of the depth of the sacral canal at the apex of the sacral hiatus and the length of the sacrococcygeal ligament between the apex of the sacral hiatus and the sacral base to predict a difficult CEB were 3.7 mm and 17.6 mm, respectively. Both the depth of the sacral canal at the apex of the sacral hiatus and the length of the sacrococcygeal ligament between the apex of the sacral hiatus and sacral base are significant variables affecting the difficulty of the CEB.

Weight-based determination of spinal canal depth for paediatric lumbar punctures

ObjectivesThe aim of this study was to evaluate whether spinal canal depth (SCD), measured using ultrasound, could be estimated from simple body measurements in a sample of children.MethodsWe measured SCD...

Morphometric Study of Sacral Hiatus with Significance in Interventional Clinical Procedure

Introduction: The sacral hiatus is an important portal for interventional clinical procedure. Identification of sacral hiatus is usually easy but sometime it becomes difficult particularly in obese person. Aim of present study was to identify additional anatomical landmarks to increase the success rate of trans-sacral hiatal procedure. Methodology: The morphometric study was conducted on 31undamaged adult sacra. The measurements were done with the help of Vernier caliper and goniometer. Results : The posterior superior iliac spines impose upon upper part of lateral sacral crest (superolateral crest). The distance between two superolateral crests was considered as the base and distance from two superolateral crests to apex of sacral hiatus as two sides of the triangle. The base, right side and left side of the triangle were 65.81 mm ± 4.00mm, 66.74 mm ± 6.18 mm and 66.84mm ± 6.07m respectively. The mean depth (AP diameter) of sacral canal at the apex of sacral hiatus was 4.17 mm ± 1.18 mm. An additional important landmark, the mean distance from the level of sacral cornua to the level of S2 foramina was 59.23mm ± 4.77mm. Conclusion: The triangle formed by the two superolateral crests and apex of the sacral hiatus was an equilateral triangle in most of the sacra and this is very important parameter in localization of sacral apex in transacral hiatal procedures. The AP diameter of sacral canal at the apex was adequate for passage of needle and endoscope in most of the specimens.

Clinicopathologic Correlation of Disc and Peripapillary Region Using SD-OCT

To describe a technique for evaluating peripapillary and optic nerve head (ONH) anatomy using spectral domain optical coherence tomography (SD-OCT) raster scanning in humans and compare quantifiable parameters between diagnosis categories. Ninety-five eyes of 51 consecutive patients were evaluated in this retrospective cross-sectional pilot study. Cirrus 5-line raster SD-OCTs with a resolution of 5 to 15 μm obtained through the ONH were included. A single observer manually measured neural canal opening (NCO), prelaminar canal depth (PLCD), peripapillary choroidal thickness (PPCT), and canal nerve fiber layer (CNFL) in normals, ocular hypertension, primary open-angle glaucoma (POAG), low-pressure glaucoma (LPG), secondary glaucoma, and early atrophic age-related macular degeneration. Clinical information, including central corneal thickness (CCT), was obtained via medical record review. Mean anatomical values within diagnosis categories were compared using one-way analysis of variance and multivariate analysis. Bivariate analysis was used to investigate relationships between continuous variables, and significant (p < 0.05) relationships were incorporated into the final statistical model. Horizontal NCO was significantly greater in eyes with LPG than that in normals (p = 0.021). The PPCT was thinner in age-related macular degeneration (p = 0.001) and glaucoma (p = 0.004) compared with that in controls (normals). Mean CNFL was thinner in POAG (p < 0.001) and LPG (p = 0.053) compared with that in normals. Vertical NCO was inversely correlated to CCT (p = 0.013). Multivariate analysis indicated a positive correlation between PLCD and PPCT (p = 0.008) and an inverse correlation between CNFL and PLCD (p < 0.001). Controlling for PPCT, PLCD and CCT were inversely correlated (p < 0.001). The SD-OCT raster scanning may be used to quantify ONH anatomy in humans. The NCO differences between POAG and LPG may indicate a distinct structural vulnerability in LPG. In addition, CNFL, PPCT, and PLCD may be important parameters to consider in glaucoma. The PLCD correlates with PPCT and should be considered in new models of glaucoma pathogenesis.