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Nigerian Journal of Clinical Practice Jun 2022Assessment of intravascular volume status is important in pediatric patients admitted to the emergency departments and pediatric intensive care units. Inferior vena cava...
BACKGROUND
Assessment of intravascular volume status is important in pediatric patients admitted to the emergency departments and pediatric intensive care units. Inferior vena cava (IVC) diameter and collapsibility index are used to evaluate the intravascular volume status in adults. The normal range of IVC diameter is available for adults and the normal range considered for adults is between 1.7 to 2.1 cm, but such normative data is limited for children of all ages.
AIMS
Our aim in this study was to obtain the IVC and the aorta diameter reference values and the mean vena cava collapsibility index in healthy and normovolemic children.
SUBJECTS AND METHODS
Vena cava inferior and aorta images in B mode were obtained. IVC diameter in the inspiratory and the largest IVC diameter in the expiratory were recorded, and the vena cava collapsibility index was calculated.
RESULTS
Ultrasonographic measurements were performed in total on 1938 children. A significant positive correlation was found between IVC and aorta diameters with age. The collapsibility index was found as 37.2% (SD 11.8) in the overall study population. In addition, the reference values for the IVC and aorta diameters obtained from the measurements were also acquired.
CONCLUSIONS
We believe that our IVC and aorta diameter measurements obtained from a large number of participants may be used as reference values in emergency departments and intensive care units.
Topics: Adult; Aorta; Child; Humans; Intensive Care Units; Prospective Studies; Ultrasonography; Vena Cava, Inferior
PubMed: 35708424
DOI: 10.4103/njcp.njcp_1801_21 -
Acta Ophthalmologica May 2021To investigate changes in retinal oximetry and the diameter of retinal vasculature in patients with chronic kidney disease (CKD) and relationships between retinal...
PURPOSE
To investigate changes in retinal oximetry and the diameter of retinal vasculature in patients with chronic kidney disease (CKD) and relationships between retinal vasculature and the estimated glomerular filtration rate (eGFR), provide a scientific basis for the early detection and diagnosis of CKD.
METHODS
Eighty-three patients with CKD and 103 healthy individuals were included after providing informed consent. All participants were examined using a noninvasive technology (Oxymap Inc., Reykjavik, Iceland) for measuring the arterial (SaO ) and venous (SvO ) oxygen saturation and the arteriovenous difference in oxygen saturation (Sa-vO ). The corresponding retinal vessel diameters of these arterioles (D-A) and venules (D-V) were measured. The eGFR of patients with CKD was calculated from the serum creatinine concentration.
RESULTS
In general, patients with CKD had higher mean SaO values than healthy individuals (100.15 ± 4.68% versus 97.14 ± 4.22%; p < 0.001, mean ± SD). The mean SaO in the superior temporal, superior nasal and inferior nasal quadrants significantly increased. There was no significant difference measured in the SvO when patients with CKD (63.66 ± 5.29%) and healthy individuals (62.70 ± 5.27%) were compared. The mean Sa-vO of the CKD group (36.49 ± 4.98%) was increased compared with normal subjects (34.44 ± 4.76%) (p = 0.005). The retinal arteriole diameter was narrower in patients with CKD than in normal individuals (117.53 ± 14.88 μm versus 126.87 ± 14.98 μm; p < 0.001, mean ± SD), and the arteriovenous ratio was smaller than in normal individuals (0.71 ± 0.09 versus 0.77 ± 0.09; p < 0.001, mean ± SD). Pearson's two-tailed correlation showed a significant correlation between the SaO and eGFR (R = -0.363, p = 0.001), and narrower retinal arterial calibre was significantly associated with a lower eGFR (R = 0.415, p < 0.001).
CONCLUSION
Based on our results, there were alterations in retinal oxygen saturation and vascular diameter in patients with CKD. Further studies are needed to determine whether such changes play a role in the development of CKD.
Topics: Adult; Case-Control Studies; Female; Glomerular Filtration Rate; Humans; Male; Middle Aged; Oxygen; Oxygen Consumption; Prospective Studies; Regional Blood Flow; Renal Insufficiency, Chronic; Retinal Vessels
PubMed: 32529722
DOI: 10.1111/aos.14398 -
Philosophical Transactions. Series A,... Feb 2018There is an emerging consensus that higher plants synthesize cellulose microfibrils that initially comprise 18 chains. However, the mean number of chains per microfibril... (Review)
Review
There is an emerging consensus that higher plants synthesize cellulose microfibrils that initially comprise 18 chains. However, the mean number of chains per microfibril is usually greater than 18, sometimes much greater. Microfibrils from woody tissues of conifers, grasses and dicotyledonous plants, and from organs like cotton hairs, all differ in detailed structure and mean diameter. Diameters increase further when aggregated microfibrils are isolated. Because surface chains differ, the tensile properties of the cellulose may be augmented by increasing microfibril diameter. Association of microfibrils with anionic polysaccharides in primary cell walls and mucilages leads to mechanisms of disaggregation that may be relevant to the preparation of nanofibrillar cellulose products. For the preparation of nanocrystalline celluloses, the key issue is the nature and axial spacing of disordered domains at which axial scission can be initiated. These disordered domains do not, as has often been suggested, take the form of large blocks occupying much of the length of the microfibril. They are more likely to be located at chain ends or at places where the microfibril has been mechanically damaged, but their structure and the reasons for their sensitivity to acid hydrolysis need better characterization.This article is part of a discussion meeting issue 'New horizons for cellulose nanotechnology'.
PubMed: 29277742
DOI: 10.1098/rsta.2017.0045 -
Turk Gogus Kalp Damar Cerrahisi Dergisi Jan 2020This study aims to define normal coronary artery diameters of males and females in a sample of Turkish population, compared to Asian-Indian and Western Caucasian...
BACKGROUND
This study aims to define normal coronary artery diameters of males and females in a sample of Turkish population, compared to Asian-Indian and Western Caucasian populations.
METHODS
Angiographic and demographic data of a total of 324 patients (147 males, 177 females; mean age 55.3±10.1 years; range, 32 to 82 years) who underwent elective coronary angiography with angiographically normal coronary arteries between July 2017 and March 2019 were analyzed retrospectively. Proximal diameters of major epicardial coronary arteries were measured using the Axiom Artis software according to edge detection method. All the measurements were adjusted to the body surface area. Unadjusted and adjusted values were compared between genders and with the Asian-Indian and Caucasian population samples.
RESULTS
The mean diameters of unadjusted/adjusted left main coronary artery, proximal left anterior descending artery, proximal left circumflex artery, and proximal right coronary artery were 4.5±0.6 mm/2.4±0.4 mm/m, 3.7±0.5 mm/1.9±0.3 mm/m, 3.3±0.6 mm/1.7±0.3 mm/m, and 3.4±0.6 mm/1.8±0.4 mm/m, respectively. Adjusted left main coronary artery and proximal left circumflex artery were narrower, and unadjusted proximal left anterior descending artery and unadjusted/adjusted proximal right coronary artery were larger in men, compared to women in the Turkish population. Turkish population had similar body surface area and unadjusted/adjusted coronary diameters with Caucasians, whereas adjusted proximal left anterior descending artery was larger in the Turkish population than in Asian-Indians.
CONCLUSION
Our study findings on the Turkish population contradict the traditional belief that women have narrower coronary arteries then men. Furthermore, the Turkish population have comparable adjusted/unadjusted coronary diameters with the Western Caucasians, but larger adjusted/unadjusted proximal left anterior descending artery, compared to Asian-Indians. We believe that our findings may contribute to the global data pool of normal coronary diameters and can be utilized in future studies as a database.
PubMed: 32175150
DOI: 10.5606/tgkdc.dergisi.2020.18475 -
Cureus Jun 2023Background The inconsistent morphology of the scapula is based on variable dimensions of its glenoid cavity, in addition to its broadened and truncated lateral angle....
Background The inconsistent morphology of the scapula is based on variable dimensions of its glenoid cavity, in addition to its broadened and truncated lateral angle. Its variable shapes are attributed to the spinoglenoid cavity (superior and posterior aspect of the scapula), which appears oval, inverted comma-shaped, and piriform (pear-shaped). Traumatic conditions often lead to glenoid dislocation/fracture. The precise administration of total shoulder arthroplasty with glenoid component adjustment warrants a comprehensive knowledge of scapular morphology. This study aims to assess the glenoid cavity/scapula shapes (anthropometric assessment) among individuals located in Odisha, India. Methods This cross-sectional analysis was undertaken on 74 left-sided and 70 right-sided, dry, and undeteriorated scapulae of human adult specimens obtained from the anatomy department irrespective of their gender and age. Results The glenoid cavity was most commonly inverted comma-shaped (34.02%) and pear-shaped (48.61%) while 17.36% of scapulae had oval-shaped glenoid cavities. The mean scapular breadth and length dimensions were 98.12±7.87mm and 135.76±12.85mm, respectively. Statistically insignificant bilateral variations were observed between the glenoid cavity index (mean value: 68.44±7.98%), glenoid diameter-2 (anteroposterior; mean value: 16.17±2.24mm), glenoid diameter-1 (anteroposterior; mean value: 22.67±1.53mm), and glenoid diameter (superoinferior; mean value: 36.03±2.15mm). Conclusion The size and shape of the glenoid cavity are directly associated with the dislocation of the shoulder joint and may disturb the results of total shoulder arthroplasty and rotator cuff surgeries. The current study analyzed the morphological types and diameters of the glenoid cavity in the scapulae to improve efficiency and lessen the failure proportions in shoulder arthroplasty. The study shows that morphological measurement of scapulae plays a vital role in the effective maintenance of posture and shoulder functions.
PubMed: 37415989
DOI: 10.7759/cureus.39981 -
Parkinson's Disease 2020It is currently impossible to diagnose Parkinson's disease (PD) in the premotor phase even though at the time of motor symptom onset the number of already degenerated...
BACKGROUND
It is currently impossible to diagnose Parkinson's disease (PD) in the premotor phase even though at the time of motor symptom onset the number of already degenerated dopaminergic substantia nigra neurons is considerable. Degeneration of the dorsal nucleus of the vagus nerve (VN) has been reported early in the disease course, and it could lead to impaired function of the VN, resulting in certain nonmotor symptoms of PD. Therefore, we raised a hypothesis that the loss of VN neurons could result in a smaller diameter of the VN among PD patients.
METHODS
20 PD patients and 20 age- and gender-matched individuals without any neurodegenerative disease were enrolled in a pilot study. The diameters of the right and left VNs were measured using ultrasonography, their average was calculated, and the narrower VN diameter was noted separately.
RESULTS
No difference was found between the PD and control groups neither in the average VN diameter (mean 1.17; 95% confidence interval (CI) 1.10-1.24 vs. 1.13; 1.07-1.18, mm; =0.353) nor in the narrower VN diameter (mean 1.11; 95% confidence interval (CI) 1.02-1.20 vs. 1.07; 1.02-1.13, mm; =0.421). The narrower VN diameter and the average VN diameter were not able to distinguish between PD patients and controls (area under curve (AUC) = 0.588, 95% CI = 0.408-0.767, and =0.344; and AUC = 0.578, 95% CI = 0.396-0.759, and =0.402).
CONCLUSIONS
To conclude, no differences were found in VN diameter between the PD and control groups. Therefore, our data do not support the hypothesis that PD could be associated with a smaller diameter of the VN.
PubMed: 32318257
DOI: 10.1155/2020/2627471 -
Cureus Sep 2021Purpose Variation among aqueous humor outflow from venting slits performed on glaucoma drainage device tubing often occurs even when physician technique and equipment...
Purpose Variation among aqueous humor outflow from venting slits performed on glaucoma drainage device tubing often occurs even when physician technique and equipment are held constant. Our hypothesis is that there are dimensional differences within the tubing, even among the same make and model of glaucoma drainage device (GDD) implants. Methods Prior to surgical implantation, excess glaucoma drainage tubing was collected for analysis. The tubing samples were sliced horizontally, and the external tube, internal lumen, and wall dimension measurements were collected microscopically. Groups were divided based upon brand and model and then statistically analyzed using an independent t-test. A total of 28 tubes were analyzed, consisting of 7 Molteno and 21 Baerveldt implants. Results The mean external diameter for the Molteno group was 656 ± 20µm, significantly larger than the Baerveldt external diameter of 620 ± 13µm (P<0.05). The mean internal diameter among Molteno lumens was 344 ± 13µm, also statistically larger than the mean internal diameter of 309 ± 18µm for Baerveldt tubes (P<0.05). The Molteno luminal wall width varied significantly less than the Baerveldt wall, 18% versus 28%, respectively (P<0.05). The tubings' wall widths variation translated into highly significant off-centered lumens among both brands. Conclusion Our findings suggest that there are significant variations among glaucoma implant dimensions between and within the multiple makes and models. The discrepancies among tubal wall thickness and off-centered lumens are undetectable to the naked eye. Importantly, this may result in significant aqueous humor outflow variation following the creation of venting slits secondary to the found irregular luminal diameters and tube wall thicknesses.
PubMed: 34659982
DOI: 10.7759/cureus.17771 -
BMC Ophthalmology Feb 2023This study aimed to compare anterior scleral thicknesses (ASTs) in people with emmetropia and myopia to explore the effect of myopia on AST.
BACKGROUND
This study aimed to compare anterior scleral thicknesses (ASTs) in people with emmetropia and myopia to explore the effect of myopia on AST.
METHODS
In this cross-sectional study, 93 participants (i.e., 93 eyes) with emmetropia and myopia underwent ocular imaging via anterior segment optical coherence tomography. We acquired raw B-scan OCT images along each of the four meridians (superior, inferior, nasal, and temporal), The AST was estimated from the limbus to a distance of 6 mm. The participants were aged between 20 and 50 years (mean age: 30.2 ± 8.8 years). The axial length (AL) was 22.50 ~ 33.04 mm (mean AL: 26.51 ± 2.65 mm), and the spherical equivalent (SE) was + 0.50 ~ 27.5 D (mean SE: -7.20 ± 6.5 D). The selected sample comprised 37 males and 56 females who were categorized as emmetropes, mild-moderate myopes, or high myopes. The four meridians of AST, AL, and refractive error were observed.
RESULTS
The AL was significantly negatively correlated with the four meridians of AST (the r value ranged between - 0.511 and - 0.228, P < 0.05). There was no significant correlation between age and inferior diameter (r = 0.113, P = 0.314), but age was positively correlated with the average AST of the superior, temporal, and nasal diameters (the r value ranged between 0.452 and 0.552, P < 0.05). There was no significant correlation between sex and AST (the T value ranged between - 1.816 and - 0.130, P > 0.05). Except for the inferior diameters of 1 mm, 5 mm, and 6 mm and the temporal diameter of 1 mm, the four diameters in the emmetropia group and the high myopia group were statistically significant at a distance of 0 ~ 6 mm from the limbus (P < 0.05).
CONCLUSION
The AST is negatively correlated with AL and positively correlated with age. Compared with emmetropic eyes, the AST is thinner in highly myopic eyes. Myopia affects AST, which may be useful for monitoring progression in cases of myopia.
Topics: Male; Female; Humans; Young Adult; Adult; Middle Aged; Emmetropia; Sclera; Cross-Sectional Studies; Myopia; Refraction, Ocular; Tomography, Optical Coherence
PubMed: 36782174
DOI: 10.1186/s12886-023-02775-x -
Annals of Plastic Surgery Mar 2016Lymphaticovenular anastomosis (LVA) has become an important procedure for the surgical treatment of lymphedema. In the past, the anatomy of the lymphatic system of...
INTRODUCTION
Lymphaticovenular anastomosis (LVA) has become an important procedure for the surgical treatment of lymphedema. In the past, the anatomy of the lymphatic system of animal models has been reported. However, to our knowledge, there have been few reports of animal models of LVA including training model. In this study, we report on a relatively simple and ideal animal LVA model based on peritoneal lymph ducts and veins.
PATIENTS AND METHODS
For 10 rats, diameters of lumbar lymphatic ducts and iliolumbar veins in the peritoneal cavity on both sides were measured, and LVA was performed. In addition, we measured the diameters of 28 lymphatic ducts and veins in 8 patients who had previously undergone LVA and compared the results with those obtained in this rat model.
RESULTS
The mean diameter of the lymphatic ducts was 0.61 mm, and the iliolumbar veins were 0.81 mm. On the other hand, the mean diameters of the 28 lymphatic ducts and veins of the 8 patients in whom we performed LVA were 0.58 and 0.76 mm, respectively. The differences in the diameters of the lymph vessels and veins between the rats and patients were not statistically significant.
CONCLUSIONS
We report on an LVA model involving the use of the lumbar lymphatic duct and iliolumbar veins of rats. The diameter, nature, and placement of the anastomosis using this model are very similar to that noted during real human surgery. We believe that our rat model will be useful as a practical training model for LVA and in studies on postoperative changes in LVA.
Topics: Anastomosis, Surgical; Animals; Humans; Iliac Vein; Lymphatic Vessels; Lymphedema; Male; Microsurgery; Models, Animal; Peritoneum; Rats; Rats, Wistar; Vascular Patency
PubMed: 26207544
DOI: 10.1097/SAP.0000000000000571 -
Archivio Italiano Di Urologia,... Mar 2022The objective of this study was to assess the relationship between retinal vessel diameters, such as retinal arteriolar diameter, retinal venular diameter, and...
OBJECTIVE
The objective of this study was to assess the relationship between retinal vessel diameters, such as retinal arteriolar diameter, retinal venular diameter, and arteriolar/venular ratio (AVR), as clinical parameters of fertility in varicocele patients.
MATERIALS AND METHODS
Sixty-eight (68) infertile varicocele men with abnormal semen parameters and sixty-one (61) varicocele normozoospermic men were included in the study. Moreover, fifty-eight (58) healthy normozoospermic men without varicocele were enrolled as a control group. For each participant, retinal vascular diameters were measured from the digital retinal photographs as a central retinal arteriolar equivalent (CRAE), central retinal venular equivalent (CRVE), and AVR. In addition, hormones (total testosterone and FSH), and semen parameters were assessed and correlated with retinal vessel diameters.
RESULTS
The mean CRAE, CRVE, and AVR values were 147.8 ± 15.8 μm, 198.3 ± 39.3 μm, and 0.61 ± 0.01 in infertile varicocele patients, respectively. Significant difference of CRAE, CRVE, and AVR were found when comparing infertile varicocele patients with both varicocele and control normozoospermic male groups (p = 0.01, p = 0.006, and p = 0.007; respectively). Larger retinal venular caliber and smaller AVR ratio showed a significant inverse correlation with both sperm parameters and hormones (total testosterone and FSH) (p < 0.05). No significant correlations were found between CRAE with both sperm parameters and hormonal values (total testosterone and FSH) (p > 0.05).
CONCLUSIONS
Infertile patients with varicocele showed a significant relationship with the retinal vascular diameter (CRVE and AVR ratio). This finding supports recommendation for regular eye examinations in the varicocele population.
Topics: Humans; Infertility; Male; Photography; Retinal Vessels; Varicocele
PubMed: 35352529
DOI: 10.4081/aiua.2022.1.70