Geometry of the Clavicle and Reliability of Measurement using PACS

Purpose

To investigate the geometry of the clavicle and to assess the reliability of Picture Archiving Communication System (PACS) for its measurement.

Methods

One hundred pairs of dry clavicles from 78 males and 22 females were measured on radiographs using PACS. Measurements included all of the following parameters: length, width, medial and lateral angulation. The intraclass correlation coefficient (ICC) for the inter-observer and intra-observer reliability was calculated.

Results

The mean left clavicle length among males and females was 149.25 ± 9.64 and 133.30 ± 8.32 mm, respectively. The respective mean right clavicle length among the males and females was 147.77 ± 9.99 and 132.08 ± 6.92 mm. The clavicles from male cadavers were significantly longer, wider and thicker than those from females, on both the left and right (P < 0.05). Among both the male and female clavicles, the left side was significantly longer than the right (P < 0.05). There was good to excellent intra-observer reliability (ICC > 0.70) for all parameters. Inter-observer reliability was also found good to excellent for all parameters except for medial clavicular angulation; for which there was fair reliability (ICC = 0.697).

Conclusion

The geometry of the clavicle is influenced by sex and side. Use of PACS as a measurement tool is reliable. Data from this study will be useful for pre-contouring plate or improving future designs of the anatomical plate of the clavicle.     

The incidence and structure of the fabella in a South African cadaver sample

The fabella, a sesamoid bone located in the tendon of the lateral head of the gastrocnemius muscle, was dissected from 102 lower limbs of 51 cadavers of age range 40–95 years (mean, 75.5 ± 14.5 years). The incidence of this sesamoid was determined as were its dimensions and radiological and histological features. The fabella was present in 23.5% of individuals, and it was bilaterally located in 50% of cases. It had an equal likelihood of occurring in males or females (P = 0.60), and in either right or left lower limb (P = 1.0). The consistency of the fabella was mostly bony (72.2%), a variety predominantly seen in male subjects. The mean diameters were 9.98 ± 0.9 mm and 8.78 ± 1.23 mm in males and females, respectively, with a statistically significant difference of P = 0.033. Histologically, bony fabellae had a core of spongy bone surrounded by compact bone, whereas nonbony fabellae were characterized by fibrocartilage. Clin. Anat. 24:84–90, 2011. © 2010 Wiley‐Liss, Inc.     

Osteometric Dimensions of the Laminas of the Spine

The present study was undertaken to evaluate the dimensions of the laminas from C2 to L5 by using adult human spine specimens for the objective of providing a set of quantitative data for the laminas from C2 to L5 vertebrae.There exists enormous amount of Anatomic data based on facet and pedicle parameters by different research workers, but it seems that the detailed studies based on measurements of laminar parameters from cervical to lumbar spines are almost nil.Forty spines (920 vertebrae) were considered for the present study. Anatomic evaluation of the laminas'included the laminar height, width, thickness, width angle & slope angle.The greatest laminar height was observed at T11 for males & females ( 22.8 ± 2.1 mm, 23.0 + 1.8mm) respectively. There was a marked change in pattern at L5 where there was a decrease in laminar height from that of preceding lumbar levels.The greatest laminar width was at-L5 for males & females (12.1 ± 2.4mm 11.5 ± 2.1 mm ) respectively. The laminar thickness was maximum at T3 for males and females (5:2 ± 0.7mm & 5.1 ± 0.2mm ) respectively. The maximum width angle was at T9 for males (99.2 ± 9.7mm) & at L4for females (100.6 ± 12.3mm). The-slope angle was maximum at L5 for males and females (113.5 ± 4.8mm & 118.0 ± 1.4mm) respectively.Thus, for the proper, understanding of the weight transmission through the spine and it related hypothesis the Anatomic parameters of the laminas provided by the present study are very important and also they provide an adequate database necessary for the surgical placement of sublaminar instruments in spine related surgeries.     

A three-dimensional study of the atlantodental interval in a normal Chinese population using reformatted computed tomography

The atlantodental interval has been usually used for the evaluation of atlantoaxial instability. However, the asymmetry of the lateral atlantodental interval is occasionally found in healthy individuals. Controversy therefore exists as to the clinical significance of this asymmetry in patients after trauma. The purpose of this study was to determine the normal range of atlantodental intervals in normal individuals using reformatted computed tomography. In this study, C1–C2 vertebrae were imaged in 230 adult patients by a Lightspeed Vct CT (General Electric, CT, USA) with a slice thickness of 0.625 mm. After reformatting the original images, the anterior atlantodental interval (AADI) and lateral atlantodental interval (LADI) were measured. The AADI was found to be 1.83 ± 0.46 mm (0.9–3.4 mm) in males and 1.63 ± 0.43 mm (0.5–3.2 mm) in females. The AADI was significantly greater in males than in females (p < 0.05). The 95% confidence interval for AADI was 1.75–1.90 mm in males and 1.54–1.72 mm in females. No statistically significant differences were found between males and females in the left and right LADI, and LADI asymmetry. The left LADI was found to be 3.38 ± 0.87 mm (1.7–6.0 mm), and the right LADI was 3.42 ± 0.84 mm (1.7–5.9 mm) in males, while the left LADI was 3.30 ± 0.73 mm (1.5–5.3 mm) and the right LADI was 3.37 ± 0.92 mm (1.7–5.9 mm) in females. The 95% confidence interval for left LADI was 3.23–3.52 and 2.94–3.25 mm, and for right LADI was 3.27–3.56 and 3.18–3.56 mm in males and females, respectively. The mean asymmetry of LADI was 0.76 ± 0.66 mm (0.0–3.5 mm) in males and 0.73 ± 0.70 mm (0.0–3.7 mm) in females. The 95% confidence interval for LADI asymmetry was 0.65–0.87 mm in males and 0.59–0.88 mm in females. Most of the population was found to have an asymmetry ranging between 0.1 and 2.0 mm. The current study shows that LADI asymmetry is common in patients without any cervical spine abnormalities. LADI asymmetry may be a normal anatomic variant and there is no evidence to confirm that LADI asymmetry is a sensitive or specific indicator of traumatic atlantoaxial instability. Radiologists and clinicians should be aware of this normal range of asymmetry when interpreting CT scans of the atlantoaxial region.     

Anatomic position of the asterion in Kenyans for posterolateral surgical approaches to cranial cavity

The asterion, defined as the junction between lambdoid, parietomastoid, and occipitomastoid sutures, has been used as a landmark in posterolateral approaches to the posterior fossa. Its reliability however has been put into question due to its population‐specific variability in position, using external palpable landmarks and its relation to the transverse–sigmoid sinus complex. This study aimed at determining the anatomic position of the asterion in a Kenyan population. Measurements from the asterion to the root of zygoma and the tip of mastoid process, respectively were taken on both left and right sides of 90 (51 male, 39 female) human skulls. The relation of the asterion to the transverse–sigmoid sinus junction was also determined. The distances on the right and left sides from the asterion to the root of the zygoma were 58.85 ± 2.50 mm and 58.44 ± 2.12 mm, respectively. The asterion was 47.89 ± 3.72 mm above the tip of mastoid process on the right side and 47.62 ± 2.87 mm on the left side. This point was significantly higher in males (48.36 ± 2.72 mm) than in females (46.62 ± 3.37 mm) with a P‐value of 0.041. Regarding its position from the transverse–sigmoid sinus junction, it was at the junction in 72 cases, below it in 17 cases (average 3.68 mm) and only one case had the asterion above this junction (2.57 mm). The asterion therefore can reliably be ascertained using the parameters from the root of the zygoma and the tip of the mastoid process. The safest approach would be posteroinferior to the asterion so as to avoid lacerating the transverse–sigmoid sinus complex. Clin. Anat. 23:30–33, 2010. © 2009 Wiley‐Liss, Inc.     

Load–deformation properties of the ligament of the head of femur in situ

The ligament of the head of femur (LHF) or ligamentum teres has been reported to tense during hip adduction and also to provide mechanical stability to the joint. LHF injury is more common in females and also in right hip joints compared with left ones. Although this could be due to leg dominance, pelvic size or muscle strength, there is no study that has looked into these differences. This cadaveric biomechanical study aimed to compare potential differences in the mechanical behavior of the LHF between neutral and 20° adducted hip joints, sex, and sides. Tensile tests of the LHF were performed on 25 hip joints (mean age at death of 85.7 ± 7.5 years; 9 females, 4 males; 13 left, 12 right), positioned either neutrally or in adduction. The maximum force required to rupture the ligament, its strain at failure, tensile strength, linear stiffness, and elastic modulus were obtained and statistically compared between analysis groups. The maximum force the LHF could withstand before rupture averaged 57 ± 37 N, strain at failure of 59 ± 33%, tensile strength of 2.9 ± 1.8 MPa, linear stiffness of 5.4 ± 3.5 N/mm, and elastic modulus of 7.2 ± 3.8 MPa. The LHF length at failure was significantly greater in males compared with females (P = 0.02). Irrespective of joint position, there were no statistical differences in the stress–strain properties of the LHF between females and males, or sides. There may be other anatomical, functional, and demographic factors that could render the ligament tissue vulnerable to injury in these groups. Clin. Anat., 33:705–713, 2020. © 2019 Wiley Periodicals, Inc.     

Brain weight of Northwest Indian children and adolescents

Brain weight of 708 individuals, 329 neonates (211 males and 118 females), 142 infants (101 males, 41 females), and 237 children and adolescents (136 males and 101 females), from Chandigarh region of northwest India were measured. Brain weight was 371.9 ± 89.5 gm in male newborns and 342.5 ± 72.2 gm in female newborns (P > 0.05). It increased to 444.7 ± 87.2 gm in the former and 405.0 ± 78.5 gm in the latter at the end of the neonatal period (28 days). Brain weight increased to 845.7 ± 163.4 gm in males and 803.0 ± 100.1 gm in females at the end of 12 months (P > 0.05), and then to 1241.9 ± 104.5 gm in the age group of 5–6 years in males and to 1101.3 ± 37.5 gm in the age group of 3–4 years in females. Thereafter, there was a gradual increase in the brain weight to 1326.9 ± 126.9 gm in male and 1206.3 ± 86.4 gm in female adolescents in the age group of 16–17 years (P < 0.01). By the age of 6 years, about 94.5% (95.6% in males and 93.3% in females) of adult brain weight was attained. Sex differences became evident after the age of 14 years. Relationships between brain weight and age, supine body length, body weight and body surface area were also considered. Am. J. Hum. Biol. 10:505–509, 1998. © 1998 Wiley-Liss, Inc.     

Serrated Flippers and Directional Asymmetry in the Appendicular Skeleton of the Commerson's Dolphin (Cephalorhynchus commersonii)

Presence of saw‐toothed structures (serrations) on the leading edge of the flippers in the Commerson's dolphin and their relation with directional asymmetry in the appendicular skeleton were investigated in individuals from the Tierra del Fuego population, Argentina. Serrations were more frequent in the left flipper than in the right (P < 0.001) and in males than in females (P < 0.001). Serration length was significantly longer in the left flipper than in the right (P = 0.023), in males than in females (P = 0.004), and in older individuals than young (P < 0.001). The length of the radius (P = 0.028) and the length (P = 0.004), width (P < 0.001) and weight (P = 0.006) of the scapula showed significant directional asymmetry favoring the right side, whereas the length (P < 0.001) and width (P < 0.001) of the second digit favored the left side. The asymmetry appears to be innate in the species but is likely to be enhanced by differential mechanical stress between flippers as a result of lateralized behavior. We propose that the left flipper would be more flexible and preferably used in sensory or tactile activities that involve the serrations, whereas the right flipper would be more responsible for actions requiring a larger muscular exercise, possibly related to the maintenance of stability during swimming. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.     

Evidence of a greater onset threshold for sweating in females following intense exercise

We evaluated the hypothesis that females would show a greater postexercise hypotension and concurrently a greater increase in the onset threshold for sweating. Fourteen subjects (7 males and 7 females) of similar age, body composition, and fitness status participated in the study. Esophageal temperature was monitored as an index of core temperature while sweat rate was measured by using a ventilated capsule placed on the upper back. Subjects cycled at either 60% (moderate) or 80% (intense) of peak oxygen consumption followed by 20-min recovery. Subjects then donned a liquid-conditioned suit used to regulate mean skin temperature. The skin was then heated (∼4.3°C·h⁻¹) until sweating occurred. Esophageal temperatures were similar to baseline before the start of whole body warming for all conditions. The postexercise threshold values for sweating following moderate and intense exercise were an esophageal temperature increase of 0.10 ± 0.02 and 0.22 ± 0.04°C, respectively for males, and 0.15 ± 0.03 and 0.34 ± 0.01°C, respectively for females. All were elevated above baseline resting (P < 0.05) and a significant sex-related difference was observed for sweating threshold values following intense exercise (P < 0.05). This was paralleled by a greater decrease in mean arterial pressure in females at the end of the 20-min recovery (P < 0.05). In conclusion, females demonstrate a greater postexercise onset threshold for sweating, which is paralleled by a greater postexercise hypotensive response following intense exercise.     

Anthropometric measurements of external ear of medical students in Uttarakhand Region

Objective: This study aimed at determining the mean values of the different morphometric measurements from right and left ears and at giving information about sex-related dimensions of ear, right-left symmetry, and age-related changes. Methodology: Measurements are taken from 177 healthy young medical students (84 women and 93 men) aged 17–25 years using a vernier calliper. The parameters measured were total ear height (TEH), ear width (EW), lobular height (LH), and lobular width (LW) for each subject's right and left ears. Result and conclusion: The mean values for TEH, EW, LH and LW, ear and lobular index in female subjects were found to be respectively 5.77 ± 0.38 cm, 2.87 ± 0.28 cm, 1.68 ± 0.21 cm, 1.95 ± 0.22 cm, 49.79 ± 4.75 cm, 116.86 ± 15.01 cm for left ear, and 0.74 ± 0.38 cm, 2.88 ± 0.22 cm, 1.67 ± 0.24 cm, 1.92 ± 0.21 cm, 50.26 ± 4.09 cm, 117.33 ± 19.28 cm for the right ear. However, in the male subjects, these values were, respectively, 6.03 ± 0.33 cm, 3.06 ± 0.25 cm, 1.69 ± 0.20 cm, 1.96 ± 0.23 cm, 50.75 ± 3.92 cm, 117.33 ± 16.70 cm for left ear, and 6.04 ± 0.36 cm, 3.02 ± 0.21 cm, 1.66 ± 0.20 cm, 1.96 ± 0.20 cm, 50.21 ± 3.88 cm, 119.07 ± 14.60 cm for the right ear. Comparisons were performed by independent t-test and paired samples t-test. All ear dimensions were significantly larger in males than in females (p < 0.001) and a significant effect of age was found.     

Minimal effects of nitric oxide on spatial blood flow heterogeneity of the dog heart

 Eleven Beagle dogs were studied to elucidate the possible role of L-arginine-derived nitric oxide on local blood flow distribution in left and right ventricular myocardium. Local blood flow was determined in 256 samples from the left and 64 samples from the right ventricle per heart using the tracer microsphere technique (mean sample mass 319 ± 131 mg). Nitric oxide production was effectively inhibited by intravenous infusion of 20 mg/kg nitro-L-arginine methylester (L-NAME) as evidenced by a shift of the dose/response curve for the effect of intracoronary administration of bradykinin (0.004–4.0 nmol/min) on coronary blood flow. L-NAME enhanced left and right ventricular systolic pressures from 132 ± 18 to 155 ± 15 mm Hg and from 26 ± 3 to 29 ± 3 mm Hg respectively (both P = 0.043). Mean left ventricular blood flow was 1.14 ± 0.38 before and 0.99 ± 0.28 ml min^–1 g^–1 after L-NAME (P = 0.068), while right ventricular blood flow fell from 0.72 ± 0.28 to 0.53 ± 0.20 ml min^–1 g^–1 (P = 0.043). Coronary conductance of left and right ventricular myocardium fell by 31 and 43% respectively (both P = 0.043). The coefficient of variation of left ventricular blood flow was 0.26 ± 0.07 before and 0.29 ± 0.07 after L-NAME (P = 0.068), that of right ventricular blood flow was 0.27 before and after L-NAME. Skewness (0.51) and kurtosis (4.23) of left ventricular blood flow distribution were unchanged after L-NAME, while in the right ventricle skewness decreased from 0.54 to 0.09 (P = 0.043) and kurtosis (3.68) tended to decrease after L-NAME (P = 0.080). The fractal dimension (D = 1.20–1.27) and the corresponding nearest-neighbor correlation coefficient (r _n = 0.37–0.53) of left and right ventricular myocardium remained unchanged after infusion of L-NAME. From these results it is concluded that firstly, local nitric oxide release does not explain the higher perfusion of physiological high flow samples and secondly, that spatial myocardial blood flow coordination is not dependent on nitric oxide. Received: 11 July 1996 / Received after revision: 29 October 1996 / Accepted: 17 December 1996     

Sectional anatomy of the adrenal gland in the coronal plane

To provide practical anatomic data for the imaging diagnosis and surgical treatment of adrenal disease, we investigated the anatomy of the adrenal gland and its relationships to regional structures using 31 sets of serial coronal sections of upper abdomen of Chinese adult cadavers and correlated coronal magnetic resonance (MR) images of ten upper abdomens of adult healthy volunteers and coronal reconstructed multislice spiral computed tomography (MSCT) images of five patients without lesions in the adrenal gland. The adrenal glands were visualized mainly on the successive coronal sections between 18 mm anterior to the posterior margin of inferior vena cava and 24 mm posterior to the posterior margin of inferior vena cava. In general, the left adrenal gland was visualized two sections earlier than the right adrenal gland. On the plane through the anterior parts of bilateral renal hili (A₁₈), the appearance rate of bilateral adrenal glands was 100%, and the maximal measurements of bilateral adrenal glands were visualized. The length, width, thickness of right adrenal body, thickness of medial limb and lateral limb were, respectively, 34.02 ± 2.12 mm, 10.91 ± 0.89 mm, 5.82 ± 0.26 mm, 2.78 ± 0.08 mm, 2.62 ± 0.06 mm, whereas the measurements of left adrenal gland were 28.31 ± 2.46 mm, 18.40 ± 1.06 mm, 6.84 ± 0.24 mm, 3.02 ± 0.08 mm, 2.86 ± 0.07 mm, respectively. The coronal plane has superior advantage in showing the bilateral adrenal glands. The shapes of adrenal glands are various, whereas the range of adrenal thickness is quite narrow. The thickness of adrenal medial and lateral limbs, especially the thickness of lateral limb are useful for the diagnosis of the bilateral adrenocortical disease.     

翼腭间隙的横断层解剖及临床意义

目的为翼腭间隙疾病的影像诊断提供解剖学资料。方法选用成年尸体头颈部20例制成连续横断面,观察翼腭间隙及其结构的解剖学关系,利用游标卡尺及求积仪分别测量其长径、宽径和面积。结果翼腭间隙形态多变,在蝶骨体层面较固定,与翼突形态密切相关、经圆孔、蝶骨体、翼突和翼窝层面的面积分别为:(40.40±2.42)mm2(左)、(43.10±2.88)mm2(右);(110.20±3.32)mm2(左)、(115.56±2.52)mm2(右);(93.20±2.76)mm2(左)、(90.82±3.12)mm2(右);(5.48±3.02)mm2(左);(5.26±2.74)mm2(右),两侧翼腭间隙及其结构呈对称性,断面长径、宽径和面积均无显著性差异(P>0.05)。横断面可清晰显示翼腭间隙前、后、内侧和外侧壁上的结构及圆孔、翼管、蝶腭孔、翼上颌裂和眶下裂等自然通道。结论翼腭间隙的横断层解剖对翼腭间隙疾病的影像诊断具有重要临床意义。     

Optic Chiasm Morphometric Changes in Multiple Sclerosis: Feasibility of a Simplified Brain Magnetic Resonance Imaging Measure of White Matter Atrophy

Sophisticated volume measurements of brain structures on magnetic resonance imaging (MRI) may improve specificity in determining long‐term progression of multiple sclerosis (MS), but these techniques are laborious. The optic chiasm (OC) is a white matter (WM) structure clearly visible on a routine MRI and is related to the optic nerves (ONs), which are known to atrophy in MS. We hypothesized that OC morphometric measurements would show OC atrophy in MS compared to normal patients. If so, this could help establish a novel simplified brain MRI measure of WM atrophy in MS patients. We retrospectively evaluated standard brain MRIs of 97 patients with known MS and 98 normal individuals. We electronically measured eight OC morphometrics on axial T2WIs and midsagittal T1WIs: OC width and anteroposterior (AP) diameter, diameters of each ON and optic tract (OT), and angles between the ONs or OTs. Mean OC width, AP diameter, and height in MS patients were 11.83 ± 1.25 mm (95% CI 11.58–12.09), 2.99 ± 0.65 mm (95% CI 2.85–3.12), and 2.09 ± 0.37 mm (95% CI 2–2.19), respectively. In normal individuals, they were 12.1 ± 1.4 mm (95% CI 11.78–12.34), 3.43 ± 0.63 mm (95% CI 3.3–3.58), and 2.15 ± 0.37 mm (95% CI 2.07–2.23), respectively. There were statistically significant differences between MS patients and controls for AP diameter (P = 0.000), but not for width (P = 0.204) or height (P = 0.183). The ONs were significantly smaller in MS (P < 0.0017), but not the OTs. Thus, the OC is significantly atrophied in an unstratified cohort of MS patients. Future studies may establish an MRI OC morphometric index to evaluate demyelinating disease in the brain. Clin. Anat. 32:1072–1081, 2019. © 2019 Wiley Periodicals, Inc.     

正常成人锁骨形态的CT影像学研究

目的 观察测量锁骨CT影像学形态,为锁骨骨折锁定接骨板的治疗及改进提供解剖学参考。方法 回顾性研究2014年3—12月南京鼓楼医院排除锁骨骨折及其他可影响锁骨形态疾病的32例行肺部或颈部CT扫描患者的影像学资料,其中男16例,女16例;年龄20~75岁,平均年龄41.4岁。通过CT扫描及3D重建,分别测量32例64侧投影位锁骨的长度,近端、中段和远端宽度,锁骨近端和远端的曲率半径,锁骨水平面、冠状面的两端最大宽度及中间最小宽度等,采用成组t检验,分别比较不同侧别及性别间测量数据的差异。结果 男性锁骨的平均长度为(153.9±7.5)mm、女性锁骨的平均长度为(135.4±7.6)mm。男女的锁骨近端曲率半径均明显较远端曲率半径大,垂直投影的锁骨中段最小宽度男性为(11.7±1.9)mm,女性为(9.3±1.0)mm。左右侧各观察测数据差异均无统计学意义(P值均>0.05);男女性别间比较,除中远段曲率半径、中近段角度、中远段角度、冠状面近端最大宽度、上缘曲度差异均无统计学意义(P值均>0.05),其他指标差异均有统计学意义(P值均<0.05)。结论 锁骨的形态存在较大的性别差异,表现为女性锁骨的总长度及各部分长度较短、水平面和冠状面近端最大宽度较小,有必要根据性别差异改进器械;此外,测量结果还可为锁定接骨板术前预弯提供依据。     

Glomerular size and volume distributions for cranial,medial, and caudal divisions of domestic fowl kidneys

Separate renal arteries and renal portal veins supply the three divisions of domestic fowl kidneys, leading to uncertainty concerning the structural and functional homology of the different divisdions. To assess the degree of anatomical similarity, separate glomerular size and volume distribution profiles were constructed for cranial, medial, and caudal divisions from the left and right kidneys of male and female domestic fowl. There were no significant differences between left and right divisions (intradivision comparisons) or between cranial, medial, and caudal divisions (interdivision comparisons) when the total number of glomeruli or total glomerular volumes were compared on a per gram kidney weight basis. Glomerular size distribution profiles were unimodal in shape, with the peaks for all divisions falling in the 0.15–0.22 mm circumference range in males and in the 0.19–0.26 mm circumference range in females. There were no significant differences in glomerular size distribution profiles for intradivision (left vs. right) comparisons. Interdivisional comparisons revealed that medial divisions had significantly lower values than caudal divisions in one of 11 glomerular circumference categories. For all remaining comparisons, there were no significant dífferences in glomerular size distribution profiles, nor were there any significant interdivisional differences when glomerular volume distribution profiles were compared. These data indicate that the three divisions of domestic fowl kidneys are structurally homologous on a per gram kidney weight basis, suggesting the separate divisions also are functionally homologous.     

颞下间隙的矢状和冠状断层解剖及临床意义

目的为颞下间隙疾病的影像诊断提供解剖学资料。方法选用成尸头颈部40例制成连续矢、冠状断面,观察颞下间隙及邻近结构的解剖学关系,利用游标卡尺及求积仪分别测量其径线和面积。结果颞下间隙的矢、冠状断面呈不规则形,经茎突等层面的面积分别为:(450.6±4.62)mm2(左)、(452.2±4.71)mm2(右),(625.3±6.05)mm2(左)、(627.7±6.13)mm2(右),(153.8±3.41)mm2(左)、(155.3±3.52)mm2(右),(350.9±4.58)mm2(左)、(352.8±4.49)mm2(右),两侧颞下间隙及邻近结构呈对称性,长径、横径和面积的差异均无统计学意义(P>0.05)。冠状面上自翼内肌上缘至卵圆孔内侧壁的连线可区分颞下间隙与咽旁间隙。翼外肌、茎突和翼突是CT等影像诊断的重要解剖学标志。结论颞下间隙的矢、冠状断层解剖对疾病的影像诊断具有重要意义。     

Kidney of elephants

Background: Elephants are an important and isolated order. Their kidneys need substantial investigation and hitherto have not been portrayed even by a pyelogram. Methods: Pyelograms and injection of vessels with colored acrylic emulsions were done initially. Dissection was under fiberoptics using a dissecting microscope with frequent measurements. Special areas were cut for microscopy (light and electron) and photography. Glomerular counts were done by macerating weighed pieces of cortex and later finding the cortical fraction of the renal parenchyma. Results: The elephant kidney is devoid of dorsoventral symmetry. It is composed of 8 ± 2 lobes separated by fine interlobar septa. There is no reduction of lobes with maturity. The pelvis bifurcates at the sinus into primary branches or infundibula which dispatch a secondary branch or infundibulum into every lobe. Interlobar arteries and veins, nerves, fat, and connective tissue generally accompany every secondary infundibulum into its lobe. A major branch of the renal artery may perforate the renal capsule and course to the cortico-medullary (C-M) border independently of the secondary infundibulum to that lobe. The number of glomeruli per kidney is approximately 15 × 10⁶. In adults the glomerular mass is 4.9 ± 0.5% of the renal parenchyma and 6.7 ± 0.3% of the cortex. Areae cribrosae occur generally at low papillae. They are the outlets of numerous terminal collecting ducts which may be accompanied by a tubus maximus (T.M.) A T.M. of diameter 1.6 mm and length 10 mm may act as the only substitute for an area cribrosa. Wide anastomoses between the two main renal veins occur within the renal sinus. Intralobar arteries and veins often course right through the outer medulla to and from, respectively, the C-M border. Conclusions: Anatomically, an elephant's kidneys appear to be able to concentrate urine only moderately. Their kidneys tend to resemble those of the manatee but not of the dugong. © 1995 Wiley-Liss, Inc.