Prevalence Of Anatomical Variations Research Articles

Deep Learning-Based Automated Quality Assurance for Palliative Spinal Treatment Planning in Radiotherapy

Robustquality assurance (QA) for palliative spine radiation therapy (RT) remains critical due to the risk of wrong anatomic level treatment on account of human error in enumerating vertebral bodies accurately based on morphology with incomplete imaging of the spine and prevalence of anatomic variants (10%). We propose a rapid, fully automated deep learning-based QA (DL-QA) tool for segmenting and enumerating vertebral structures from image data, capable of identifying misalignment based on discrepancies in calculated dose coverage. Ina retrospective cohort of 514 patients who received palliative spine radiation treatment at a single institution for spinal metastases, vertebral volumes for each individual spine level were automatically segmented on RT planning computed tomography scans using a publicly available deep learning algorithm, Total Segmentator (TS) deployed in the treatment planning system (Wasserthal et al, 2022). Departmental policy requires that the prescription/plan name include all spinal levels that receive a prescribed dosimetric threshold of V50% > 50%. By comparing the intended spine level target in the prescription and plan name against the TS volumes, the DL-QA flagged all cases for which any target vertebrae did not receive this threshold dose and/or any non-targeted vertebrae that received V50% > 50%. To detect spine anomalies, cases were also flagged if any vertebrae volume was not within ±1σ of the entire population of vertebrae volumes. Flagged cases were either categorized as: (1) wrong spine level RT error; (2) documentation error, in which treatment was correct but the prescription/plan name did not follow Departmental policy; or (3) potential spinal geometric error. All flagged cases were verified manually by checking the original images and treatment planning data. Outof 514 patients, 29 cases were flagged as potential errors. Manual review revealed that one of these was a previously discovered true treatment error (due to anatomic variant with 4 lumbar bodies) while 10 were treated as intended but showed documentation errors due to variants in the number of vertebral bodies, kyphosis of the spine causing non-targeted vertebrae to appear in the treatment field, or improper observation of the Departmental plan naming policy. The remaining 18 cases were associated with flagged vertebrae volumes. Reviewing those patients, we identified spinal anomalies where TS attempted to account for extra or missing vertebrae (N = 9) and cases where TS made segmentation errors (N = 9). Theproposed automated DL-QA system successfully identified patients with spine anomalies, flagged documentation errors, verified the correct target levels of spine RT treatments, and detected a known misadministration. The next phase will involve prospective testing of the system in a clinical setting upstream of treatment delivery.

Comparison of Low-Dose Non-contrast CT in Detecting Anatomical and Surgically Important Variants of Paranasal Sinuses to Standard Dose Non-contrast CT: Experience from a Tertiary Care Hospitalin Sub-Himalayan Region of Northern India.

Computed tomography (CT) is the gold standard for diagnosing sinusitis and anatomical variations and a guide for paranasal sinus (PNS) surgeries. High doses of radiation lead to increased risk of head and neck malignancies, radiation-induced cataracts, hypothyroidism, and hyperthyroidism. The purpose of this study was to assess the effectiveness of low-dose CT as compared to standard-dose CT in the identification of anatomical variants of paranasal sinus and rhinosinusitis. This was a prospective cross-sectional study consisting of 72 patients who were divided equally into cases (underwent low-dose CT for PNS) and controls (underwent CT for PNS using standard dose protocols). Prevalence of anatomical variants and sinusitis were compared. Image quality was assessed using volume CT dose index (CTDIvol), dose length product (DLP), scan length, and noise. Subjective assessment was done by two radiologists, and scores were given. The comparison and analysis of the quantitative and qualitative variables were done. Anatomical variants were comparable among cases and controls, with post-sellar sphenoid being most common and paradoxical middle turbinate being least common surgically important variant. The difference in meanSD of CTDIvol (mGy), DLP (mGy-cm), effective dose (mSv), globe, and air noise between low and standard doses was statistically significant. A moderate agreement (with kappa 0.50) in cases and substantial agreement (with kappa 0.69) in controls was observed between both observers. Low-dose CT PNS and standard-dose CT PNS are comparable in delineating the paranasal sinus anatomy, with a 3.53× reduction of effective radiation dose to patients.

Classification of Sternocleidomastoid Muscle Variations and Comparison of Its Incidence among Populations

This study aimed to classify and investigate anatomical variations of the sternocleidomastoid (SCM) muscle, which is commonly used as an anatomical landmark to indicate the correct position for central venous catheterization, in a Thai population. Thirty- five embalmed cadavers from the Northeast Thailand (19 females and 16 males) were systemically dissected to reveal the SCM muscles in both sides for gross human anatomy teaching. Variations in the SCM origin and insertion were observed and recorded. The prevalence of anatomical variations was approximately 11.4 % (4 of 35 cadavers) and was not different by sex. Such variations were classified into 5 types based on origin, insertion, and presence of additional heads, as follows: type I (n=31; 88.6 %), type II (n=1; 2.85 %), type III (n=1; 2.85 %), type IV (n=1; 2.85 %), and type V (n=1; 2.85 %). Clinical considerations and prevalence of variant SCM muscle have also been discussed. Since the incidence of this anatomical variations was more than 10 %, the cervical surgeons should seriously consider this issue before insertion of a central venous catheter to avoid complications.

Prevalence of anatomic variants in coronary arteries of Japanese Black cattle.

Coronary artery anomalies that can cause sudden cardiac death have been described in some mammals. However, few studies have investigated coronary anomalies and coronary artery branching patterns in cattle. Therefore, understanding of bovine coronary arteries is incomplete. The aim of this study was to clarify anatomic variants in coronary arteries of Japanese Black cattle. The gross anatomy of the coronary arteries was examined in the hearts of 100 cattle. A total of 14 of 100 hearts exhibited confirmed coronary anomalies in the left main trunk. These 14 hearts were classified into 5 types potentially associated with cardiac ischemia. Regarding the coronary branches, the subsinuosal interventricular branch originated from the left circumflex branch (LCX) in 98 hearts and from the right coronary artery in 2 hearts. The origin of the sinoatrial nodal branch was classified into 3 types. In 99 hearts, the atrioventricular nodal branch originated from the LCX at the heart crux. This study characterized the prevalence of coronary anomalies, branching patterns of coronary arteries, and coronary artery anatomic variants in Japanese Black cattle.

Anatomical Variations on Routine CT Scans Observed in the Paranasal Sinuse

Objective: The aim of current study is to determine the frequency of anatomical variants on routine CT scan observed in the paranasal sinus. Stud Design: Cross-sectional Place and Duration: The study was conducted at Radiology department of Jinnah Hospital, Lahore for the duration of nine months from January 2021 to September 2021. Methods: There were 90 sinus patients of both genders with ages 20-55 years in this study. Cases were recruited after informed written permission was obtained and data such as gender and BMI were collected. The prevalence of various anatomical variations of the sinonasal cavities was determined based on the results of the CT scans. Anatomical differences between individuals with low to no apparent imaging evidence of rhinosinusitis vs those with clinically substantial radiologic evidence of rhinosinusitis were examined in this study. SPSS 21.0 was used to analyze complete data. Results: Among 90 cases, the majority of the patients were males 63 (70%) and 27 (30%) were females with mean age 33.41±8.56 years and mean BMI 23.22 ±5.31 kg/m2. According to Kero’s classification to determine the difference in olfactory fossa depth, most of the patients 62 (68.9%) were in type II, 20 (22.2%) in type I and 8 (8.9%) in type III. In accordance with anatomical variation, we found that most of the patients 65 (72.2%) had deviated nasal septum (DNS) followed by agger nassi cells in 61 (67.8%) cases and concha bullosa in 35 (38.9%) cases. Conclusion: We concluded in this study that the prevalence of anatomical variants among patients of paranasl sinus was higher in which the majority of the patients had deviated nasal septum and agger nassi cells. Keywords: Frontal sinus, Paranasal Sinus, Maxillary sinus, Anatomical variants

Differences in topographical location of sacroiliac joint MRI lesions in patients with early axial spondyloarthritis and mechanical back pain

BackgroundEarly diagnostics of axial spondyloarthritis (axSpA) remains a challenge. Traditional imaging one-plane sacroiliac joint (SIJ) MRI assessment is used. By introducing a two-plane assessment system, the objective was to analyse the differences in SIJ MRI changes in early axSpA compared with changes in patients with mechanical back pain (MBP) by exploring the differences in volume and location.MethodsMRIs in the early diagnostic state of 25 axSpA patients (mean age 31.3 years) and 59 MBP patients (mean age 32.3 years) were included. The MRIs were assessed by two readers regarding the distribution of bone marrow edema (BME) in 14 joint portions and structural changes in six joint portions in addition to SIJ anatomical variations and lumbar spine disc degeneration.ResultsAxSpA patients had a significantly higher overall BME sumscore (volume) of 25.1 compared to MBP patients 6.8, p < 0.005. The MBP group had the highest prevalence (66%) and sumscore (5.7) in the middle anterior sacrum. The axSpA group had significantly higher prevalence and sumscores in all joint portions except the three cartilaginous anterior sacral joint portions, including the ligamentous compartments (prevalence 40–60% compared to 8–15%, p both < 0.005). The axSpA group had also a significantly higher prevalence of erosions and fatty marrow disposition, but there were no differences in the prevalence of anatomical variations except the bipartite iliac bony plate.ConclusionsAxSpA patients demonstrated a widespread distribution of both inflammatory and structural changes, including high BME occurrence in the ligamentous joint portions whereas patients with MBP had the highest occurrence of BME in the middle anterior sacrum. These findings may help differentiate axSpA patients from other back pain conditions in the early diagnostic phase.

Evaluating the frequency of anatomical variations of the sinonasal region in pediatric and adult age groups according to gender: computed tomography findings of 1532 cases

BackgroundThe aim of the present study was to evaluate retrospectively the frequency of anatomical variations in sinonasal region, which were frequently seen in our cases, for whom coronal section paranasal computed tomography imaging (CPNCT) was taken, as well as the correlation of these variations with age and gender and correlations of identified anatomical variations with one another.In the study, CBCT scans of a total of 1532 (825 males and 707 females) cases were evaluated in order to determine the prevalence of anatomical variations of the nasal cavity and paranasal sinuses. All the images were taken by a multi-detector CT device (Aquilion, Toshiba medical system, Tokyo, Japan).ResultsMost frequently detected three anatomical variations were septum deviation (79.7%), concha bullosa (40.9%), and ethmoid bulla (21.0%) according to the frequency order. When the frequency of anatomical variations was evaluated according to gender, septum deviation, concha bullosa, and anterior clinoid process pneumatization were more frequently observed in males and Onodi cell in females (p < 0.05).When the relationships of the anatomical variations with one another were evaluated, it was found that the possibility of the presence of concha bullosa in the septum deviation cases and the presence of ethmoid bulla in the cases with Haller cell septum were higher (p < 0.05).In terms of the anatomical variations that were evaluated by taking age as the independent variable, a statistically significant difference was observed in pterygoid process pneumatization, Haller cell, pneumatized crista galli, ethmoid bulla, and paradoxical middle concha between the adult and children age groups (p < 0.05).ConclusionIn terms of the frequency of occurrence to various sinonasal region variations, statistically significant differences were observed between both genders and age groups. The correlations of the detected variations with each other were also remarkable. Consequently, it is believed that comprehensive studies and serious objective evaluations evaluating the change of frequency of anatomical variations according to age and gender besides their correlation with each other are required.

Cone beam imaging – an imperative arm in implant planning

Recently, Dental implants have taken the dental rehabilitation to another level. Dental implants are highly preferred over other rehabilitation techniques, as they have a more conservative approach with minimal damage to other adjacent structures. The aim of the study was to evaluate the prevalence of anatomical variations in maxilla and mandible on CBCT images of patients referred for dental implants. In our study, a total of 102 CBCT images comprising of 60 males &amp; and 42 females with mean age of 50 years &amp; 45 years were analysed. We found that in approximately 50% of the cases, the anterior loop of mental nerve was seen and lingual foramen was identified in the anterior part of the mandible in about 20% cases. Two-dimensional radiographs have been used for a long time as the only diagnostic tool in implant dentistry. However, radiographs may seem to be adequate for patients with wide residual ridges but CBCT effectively brings together prosthetic and surgical considerations which are important for beauty, restoration and prosthetic indices.

Multidisciplinary studies of heavily fragmented and commingled ancient Egyptian human remains found in KV 40 (Valley of the Kings, Luxor, Egypt): A pragmatic workflow and first results

IntroductionFor archaeological projects, a systematic study of recovered human remains is essential to determine the individual characteristics of buried individuals. This publication presents a transdisciplinary workflow specially adapted for the study of heavily fragmented and commingled skeletonized or mummified ancient Egyptian human remains as found in tomb KV 40 during excavations as part of the “University of Basel Kings’ Valley Project” in the Valley of the Kings, Luxor, Egypt. Furthermore, anthropological data from this investigation are presented, and challenges and best practices of corresponding state-of-the-art investigation methods under such field conditions are discussed. Materials and methodsSkeletonized remains were first examined anthropologically. Mummified remains or those showing pathological alterations were X-rayed beforehand for non-invasive assessment of bone morphology and possible differential diagnoses. Measurements, X-ray and photographic images, as well as any additional information, were digitally stored in a specially developed database for later “off-field” analysis. ResultsThe developed workflow proved practicable and highly efficient. The minimum number of individuals (MNI = 83), age and sex distribution, adult stature, as well as the prevalence of anatomical variants (e.g., 23 individuals with supratrochlear foramen) and pathologic alterations could be established. Discussion and ConclusionDespite being fragmented and scattered as a result of looting and fire, these recovered human remains provided valuable insights into living conditions, demography and state of health during the 18th and 22nd − 25th dynasty in ancient Egypt (ca. 1370 and ca. 900–700 BCE). The results presented here, therefore, highlight the potential and the need for a trans disciplinary yet pragmatic approach for the study of such heavily commingled material.

Relationship between Sinonasal Anatomical Variations and Symptom Severity in Patients with Chronic Rhinosinusitis

Background:Anatomical variations are subtle structural abnormalities around the osteomeatal complex that might obstruct paranasal sinus drainage and ventilation. The role of these anatomical variants in chronic rhinosinusitis is still controversial and unclear. The aim of this study was to determine the prevalence of anatomical variations and their relationship with the severity of symptoms in patients with chronic rhinosinusitis.Materials and Methods:This was a cross-sectional study conducted among randomly selected patients with chronic rhinosinusitis. Sinonasal Outcome Test-20 (SNOT-20) was used to assess the patient’s severity of symptoms. Computed tomographic scan was used to determine the presence of anatomical variations. The relationship between anatomical variations and symptom severity was determined using the Statistical Products and Service Solution (SPSS) version 20.0.Results:There were 70(58.3%) males and 50(41.7%) females within the age range of 17–60 years. SNOT-20 scoring showed 6(5.0%) of the patients with mild symptoms, 69(57.5%) with moderate, 37(30.8%) with severe, and 8(6.7%) with profound symptoms. The prevalence of sinonasal anatomical variants was 26.7%, which comprised of septal deviation (10.8%), agger nasi (6.7%), concha bullosa (4.2%), Haller cells (3.3%), and Onodi cells (1.7%). There was a statistically significant relationship between the anatomical variations and symptom severity (P = 0.000).Conclusion:This study found a significant relationship between anatomical variations and severity of chronic rhinosinusitis. The prevalence of anatomical variants was found to be 26.7%.

A Systematic Review of the Prevalence of Anatomical Variations of the Renal Artery

A Systematic Review of the Prevalence of Anatomical Variations of the Renal Artery

Anatomical causes of compression of the sciatic nerve in the pelvis. Piriform syndrome

ObjectiveThe piriformis syndrome is one of the etiologies of pelvic pain due to the sciatic nerve's entrapment by the piriformis muscle. Nowadays this syndrome might be difficult to be diagnosed. The aim of this study is to know the prevalence of anatomic variations in our population that may contribute to the appearance of piriformis syndrome. Furthermore, anthropometric measurements of the piriformis muscle and the sciatic nerve procedures are studied for a possible application in the gluteal region. Materials and methodsThe study was carried out in 59 pelvis of 32 cryopreserved bodies. The anatomical variations of piriformis and sciatic nerve founded were described following the Beaton and Anson's classification. Anthropometric measurements of both structures with reference to the greater trochanter of the femur were performed. ResultsThe sciatic nerve and the piriformis had an anatomical variation in a 28.13%. The most frequent variation found was tipus II (21.64%) and tipus III (6.49%).Insertion most frequently observed was an independent piriformis tendon inserted into the trochanteric fossa with 53.85%. ConclusionsThe anatomic variations' incidence in the population studied indicates that those have to be evaluated as a differential diagnosis of gluteal region pain due to the symptoms and signs resemblance with the vertebral disc pathology involving nerve root injury. In addition, anatomical knowledge of this region can be useful for the interpretation of imaging techniques, especially when ultrasound-guided injections are performed.

Causas anatómicas de compresión del nervio ciático en la pelvis. Síndrome piriforme

ObjectiveThe piriformis syndrome is one of the etiologies of pelvic pain due to the sciatic nerve's entrapment by the piriformis muscle. Nowadays this syndrome might be difficult to be diagnosed. The aim of this study is to know the prevalence of anatomic variations in our population that may contribute to the appearance of piriformis syndrome. Furthermore, anthropometric measurements of the piriformis muscle and the sciatic nerve procedures are studied for a possible application in the gluteal region. Material and methodThe study was carried out in 59 pelvis of 32 cryopreserved bodies. The anatomical variations of piriformis and sciatic nerve founded were described following the Beaton and Anson's classification. Anthropometric measurements of both structures with reference to the greater trochanter of the femur were performed. ResultsThe sciatic nerve and the piriformis had an anatomical variation in a 28.13%. The most frequent variation found was tipus II (21.64%) and tipus III (6.49%).Insertion most frequently observed was an independent piriformis tendon inserted into the trochanteric fossa with 53.85%. ConclusionThe anatomic variations’ incidence in the population studied indicates that those have to be evaluated as a differential diagnosis of gluteal region pain due to the symptoms and signs resemblance with the vertebral disc pathology involving nerve root injury. In addition, anatomical knowledge of this region can be useful for the interpretation of imaging techniques, especially when ultrasound-guided injections are performed.

Association of nasal blockage and prevalence of anatomical variants on CT scan of nose and paranasal sinuses

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Nasal blockage is the most common nasal symptom with which patients present in ENT OPD. Sometimes, it is associated with headache and facial pain. The symptoms are secondary to mucosal contact points in the nasal cavity without any observable nasal mass, nasal discharge or turbinate hypertrophy, hence, known as rhinogenic headache or facial pain syndrome.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; This is a prospective study done in the department of otorhinolaryngology, at P.D.U. Medical College and Hospital, Rajkot, for a period of twenty months from May 2017 to December 2018. A total number of 100 CT scans of patients aged above 5 years of both genders who presented with complaints of nasal blockage at department of otorhinolaryngology, P.D.U. Hospital, Rajkot. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; Out of 100 patients above 5 years with symptoms of nasal blockage and CT scan showing anatomical variants, 78 patients had deviated nasal septum as the most common anatomical variant presenting with nasal blockage. Males (62%) were more commonly affected with different anatomical variants; 25-45 year old age group (48%) was the most common affected age group. The other anatomical variants: concha bullosa (13%), paradoxically curved middle turbinate (4%), Onodi cell (2%), Haller cell (2%) and unilateral choanal atresia (1%).&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; Nasal blockage is more common in 25-45 year old males and deviated nasal septum is the most common anatomical variant.&lt;/p&gt;

Anatomical Variants of Celiac Trunk in Relation to Its Branching: A Preliminary Sub-Saharan Study

Background: Surgical treatment of upper mesocolic organs is improved by preoperative diagnosis of anatomical variants of celiac trunk. According to the literature, these anatomical variants are little known in sub-Saharan Africa. Purpose: To evaluate the prevalence of anatomical variants of celiac trunk in relation to its branching. Materials and methods: This was a cross-sectional study of descriptive type. It retrospectively evaluated 160 abdominal contrast enhanced CT-scan, from patients attending Yalgado OUEDRAOGO teaching hospital, from 1 January 2015 to 30 September 2016. Patients with a history of heavy abdominal surgery were excluded. Images obtained by 64-row CT-scan were analyzed for anatomical variants of the celiac trunk. Results: One hundred and twenty-eight patients (80%) had a classic anatomical configuration of celiac trunk, while thirty-two (20%) had at least one anatomical variant. Two anatomical variants were found in fifteen patients (9.4%) while five other patients (3.1%) had more than two variants. The most frequent anatomical variant was the hepato-splenic bifurcation, found in fourteen patients (8, 8%). It was followed by common celiac and mesenteric trunk, and then collateral arteries, in particular left hepatic artery and right lower diaphragmatic artery, each with three patients (1.9%). Conclusion: Anatomical variants related to celiac trunk branching, are as frequent in our study as in the literature. However, the two most common anatomical variants were hepato-splenic bifurcation and common celiac and mesenteric trunk.

Assessment of prevalence of anatomical variations and pathosis of the maxillary sinuses using cone-beam computed tomography in a sample of the population of Saudi Arabia

Background: Cone-beam computed tomography (CBCT) technology has been a useful tool for decreasing dental treatment complications and ensuring more predictable treatment outcomes. Objectives: This study aimed to assess the prevalence of maxillary sinuses status in regard to anatomical variations and pathosis using CBCT as a diagnostic tool, in asymptomatic patients who are willing to receive dental implants at King Abdulaziz University Dental Hospital in Jeddah, Saudi Arabia. Materials and Methods: Both sinuses in 263 patients (140 females and 96 males) were evaluated using iCAT Classic scanner to acquire the total of 526 CBCT images. Two calibrated dental radiology consultants evaluated the CBCT of the maxillary sinuses images using the Vision software (Imaging Sciences International, Hatfield, PA, USA) for the following finding: number of teeth in intimate relation with the maxillary sinus and the presence of septa (as anatomical variations) and the presence, extent, and configuration of mucosal thickening (MT) as sign of pathosis (mucositis). Results: The highest prevalence of dental proximity to the sinus wall was between the first left premolars and the anterior sinus wall (57.14%) followed by the second right premolars (56.14%). The presence of septa in both right and left maxillary sinuses was 54.37% and 57.41%, respectively. The prevalence of sinus pathosis was 52.7%. Interestingly, 87.07% of the MT cases were due to nonodontogenic origin compared to 12.93% of odontogenic-related pathosis. Conclusions: Preoperative radiographic assessment using CBCT is highly recommended before dental implant placement in our population due to the high anatomical variations and pathosis rates, to allow proper assessment and diagnosis of maxillary sinus disease, if present. The assessment of maxillary sinus disease before surgical intervention will provide a higher standard of care and decrease the risk of complications and failures of dental implants.

Prevalence of anatomical variations of osteomeatal complex and its correlation with incidental maxillary sinus pathologies using cone-beam computed tomography: an observational study

Prevalence of anatomical variations of osteomeatal complex and its correlation with incidental maxillary sinus pathologies using cone-beam computed tomography: an observational study

Prevalence of Anatomical Variants on Computed Tomography of Nose and Paranasal Sinuses

Objective: Aim of the study was to determine the prevalence of anatomical variations of nose and paranasal sinuses based on the findings seen on computed tomography. Methodology: CT SCAN of the patients with sinonasal symptoms was performed for evaluation of the anatomical variants of nose and paranasal sinuses. The sections were then analysed for anatomical variations. The data collected was subjected to statistical analysis. Results: The most commonly encountered anatomical variation was DNS, present in 86.25% (69) of patients. Pneumatised septum was present in 25% (20) of patients. Concha bullosa was present in 28.75% (23) while Concha lamella was seen in 17.5% (14) of patients. Paradoxical middle turbinate was present in 13.75% (11) while pneumatization of uncinate process in 10% (8), pneumatized superior turbinate in 5% (4), Haller cells in 8.75% (7), prominent Agger nasi cells in 15% (12), pneumatized crista gali in 8.75% (7), Onodi cells in 20% (16), pneumatization of anterior clinoid process in 17.5% (14) while pneumatization of greater wing of sphenoid/ pterygoid process was present in 11.25% (9) of patients. Conclusion: It is very important to recognize the clinical and surgical significance of these variations. Thus, prior to FESS, imaging with CT scan is mandatory to evaluate the anatomy of PNS and its variations.

Cerebrovascular Abnormalities Supporting the Selfish Brain Hypothesis of Human Hypertension

The selfish brain hypothesis of hypertension suggests that brainstem hypoperfusion triggers increased sympathetic activity (SNA) and blood pressure (BP) as a mechanism to maintain cerebral perfusion. We assessed: 1) prevalence of anatomical variations in the posterior cerebral circulation, which may cause brainstem hypoperfusion, 2) relationships of SNA to cerebral vascular resistance (CVR) in hypertensive (HTN) vs normotensive (NTN) humans. The vertebral arteries (VA) and Circle of Willis (CoW) were imaged in 121 HTN (MR angiography). VA hypoplasia (VAH), defined as &lt;2mm diameter, together with CoW morphology were compared to known standards in &gt;50 NTN. In a cohort of HTN (n=50) and NTN (n=40), muscle SNA (MSNA, microneurography), blood flow in the internal carotid arteries (ICA) and VA (MR phase contrast), and BP were recorded.Prevalence of VAH and incomplete posterior CoW was higher in HTN vs NTN (51 vs 27% and 62 vs 38%, p&lt;0.05). Of the posterior CoW variants, complete disconnection of anterior/posterior CoW was higher in HTN (31 vs 10%, p&lt;0.05). Prevalence of having both VAH and incomplete posterior CoW variant was higher in HTN vs. NTN (38 vs 10%, p&lt;0.05). Total CVR and CVR in VA was higher in HTN vs. NTN (2.6 ±0.1 vs 1.1±0.1 and 9.5±0.1 vs 6.7±0.1 mmHg/mL/dl.tissue/min). CVR was related to MSNA in both groups (HTN; r=0.40, NTN; r=0.38, P&lt;0.05). CVR was more closely related to MSNA in the VA vs ICA in HTN (r=0.40 vs r=0.30, P=0.05).The higher prevalence of VAH and incomplete posterior CoW may cause the observed increase in CVR in HTN. The higher CVR in the posterior circulation was linked to higher MSNA in HTN, supporting the hypothesis of brainstem hypoperfusion as a driver of neurogenic hypertension.BHF.

Análise das variações anatômicas do canal da mandíbula encontradas em radiografias panorâmicas

INTRODUÇÃO: No âmbito da clínica odontológica, o bloqueio do nervo alveolar inferior é o mais utilizado; todavia, diversos estudos têm mostrado as mais altas taxas de fracasso, as quais, normalmente, têm como motivo a falha na observação da posição, da forma e da anatomia dos nervos. Essas falhas decorrentes da variação anatômica do nervo alveolar inferior já vêm sendo estudadas na literatura, através de estudos com a análise de radiografias panorâmicas, como proposto neste estudo. OBJETIVO: O objetivo deste estudo foi verificar a ocorrência e a prevalência das variações anatômicas, bem como a correlação das variações do canal da mandíbula com lado e sexo, que podem ocorrer no canal mandibular, por meio de radiografias panorâmicas de pacientes atendidos no Departamento de Odontologia da Universidade Federal de Sergipe (UFS). MATERIAL E MÉTODO: Foram analisadas 1.500 radiografias panorâmicas de pacientes atendidos pelo Departamento de Odontologia da Universidade Federal de Sergipe (UFS). Imagens radiográficas foram observadas sobre um negatoscópio, utilizando-se uma máscara preta ao redor das radiografias, em ambiente com luminosidade apropriada. RESULTADO: Neste estudo, foram observados 5,3% de bifurcações do canal mandibular; 47,5% de canais altos; 16,8% de canais intermediários; 27,1% de canais baixos, e 8,6% de canais com outras variações. CONCLUSÃO: Baseando-se na altura do canal mandibular, houve maior prevalência dos canais altos do que os demais nas mulheres, sendo que não houve diferenças entre os gêneros com relação aos demais tipos e lados afetados. Na classificação dos canais bífidos, não houve diferença estatisticamente significante entre homens e mulheres. Observou-se que a maior prevalência foi para canais sem bifurcação.