Incidental discovery of a sacral rib: a case report.

PURPOSE: The observation of an accessory bone joined to the sacrum (suggestive of a sacral rib) prompted us to describe the structure's morphology and its anatomic relationships and to consider its morphogenesis and clinical implications. METHOD: A 38-year-old woman underwent computed tomography, to characterize the extension of a thoracic mass. We compared our observations with the literature data. RESULTS: We observed a voluminous accessory bone located behind and to the right of the sacrum. The bone was articulated with the third sacral vertebra and featured a head and three processes. These characteristics were suggestive of a sacral rib. We also observed involution of the gluteus maximus. CONCLUSION: This accessory bone probably resulted from overdevelopment of a costal process and an absence of fusion with the primitive vertebral body. Sacral ribs are rare and usually asymptomatic but appear to be more prevalent in young women. The adjacent muscles are often abnormal. Awareness of the potential presence of this bone is essential for surgeons who operate on the lumbosacral junction.

Anatomical and biometric study of the radial artery on human cadavers dissected in the anatomy laboratory.

OBJECTIVE: To study the anatomy and biometry of the radial artery and to report the implications of this study for daily practice in Cardiac Surgery. METHOD: Radial arteries from 45 human cadavers (28 males and 17 females, average age 79.2 (92) fixed in 10% formalin were dissected. The proximal and distal internal calibers and lengths of these radial arteries were measured. RESULTS: Our results showed the presence of a single radial artery variation in 2.3% of the entire sample (1.1% of the 90 dissected upper limbs). The distance between the epicondyle and the emergence of the radial artery was 32.4 (6.67) mm in men and 30.7 (9.00) mm in women, with an average of 31.8 (7.58) mm. For the right upper limb, the mean proximal internal caliber of the radial artery was 3.16 (0.56) mm and its mean distal internal caliber was 2.62 (0.66) mm. For the left upper limb, the mean proximal internal caliber of the radial artery was 3.17 (0.59) mm and its mean distal internal caliber was 2.64 (0.68) mm. The mean length of the left radial artery was 197.0 (17) mm. The mean length of the right radial artery was 201.0 (33) mm. CONCLUSION: It is very important to be aware of the possible anatomical variation of the radial artery. Despite its rarity, this knowledge may ensure a better safety and reliability of the harvesting technique for use as a graft.

Microsurgical anatomy of the inferior intercavernous sinus.

PURPOSE: Intercavernous sinuses (ICSs) are physiological communications between the cavernous sinuses. The ICSs run between the endosteal and meningeal layers of the dura mater of the sella turcica. Whereas the anterior and posterior ICSs have been frequently described, the inferior ICS (iICS) has been less well studied in the literature; however, poor awareness of the ICS's anatomy can lead to serious problems during transsphenoidal, transsellar surgery. The objective of the present anatomical study was to describe the iICS in detail. METHODS: The study was carried out over a 6-month period in a university hospital's anatomy laboratory, using brains extracted from human cadavers. The brains were injected with colored neoprene latex and dissected to study the iICS (presence or absence, shape, diameter, length, distance between inferior and anterior ICSs, distance between inferior and posterior ICSs, relationships, and boundaries). RESULTS: Seventeen cadaveric specimens were studied, and an iICS was found in all cases (100%). The shape was variously plexiform (47.1%), filiform (35.3%), or punctiform (17.6%). The mean ± standard deviation diameter and length of the iICS were 3.75 ± 2.90 mm and 11.92 ± 2.96 mm, respectively. The mean iICS-anterior ICS and iICS-posterior ICS distances were 5.36 ± 1.99 mm and 7.03 ± 2.28 mm, respectively. CONCLUSION: The iICS has been poorly described in the literature. However, damage to the iICS during transsphenoidal, transsellar surgery could lead to serious vascular complications. A precise radiological assessment appears to be essential for a safe surgical approach.

Microsurgical anatomy of the subcallosal artery.

BACKGROUND AND PURPOSE: The subcallosal artery [SCA, a branch of the anterior communicating artery (ACoA)] is not well described in the literature. However, the memory disorders that can occur after surgical repair of ruptured ACoA aneurysms might be related to infarction of the SCA. The objective of the present study was to perform a thorough anatomical assessment of the SCA. METHODS: The study was carried out over a 6-month period in a University Hospital's anatomy laboratory, using brains extracted from human cadavers. The brains were injected with colored neoprene latex and dissected to study the SCA's origin, path, termination, diameter, length, and vascularized territories. RESULTS: 21 cadaveric specimens were studied. The mean ± standard deviation diameter and length of the SCA were 0.83 ± 0.57 mm and 38.14 ± 25.11 mm, respectively. The predominantly vascularized territories were the paraterminal gyrus (100%), the parolfactory gyrus (78.95%), the rostrum (84.21%) and genu (78.95%) of the corpus callosum, the lamina terminalis (78.95%), the anterior commissure (63.16%), the anterior cingulate gyrus (47.37%), and the fornix (26.32%). When the SCA supplied the fornix and the anterior cingulate gyrus, it was significantly longer and broader (p < 0.05). CONCLUSION: Anatomic knowledge of the SCA is crucial-especially for the treatment of ACoA aneurysms.

A median sacral artery anterior to the iliocaval junction: a case report-anatomical considerations and clinical relevance for spine surgery.

BACKGROUND AND IMPORTANCE: The median sacral artery (MSA) is a relatively small vessel that always arises from the posterior, terminal part of the infrarenal aorta. In most cases, the MSA runs behind the iliocaval junction. Here, we describe a very rare case of an MSA running in front of this junction. CASE REPORT: During a human cadaveric dissection of the retroperitoneal area, we unexpectedly observed that the MSA passed in front of the left common iliac vein. CONCLUSION: The anatomy of the MSA has been extensively described and variations are quite rare. On the basis of this specific case, knowledge of the anatomic interactions between the MSA and other lumbar retroperitoneal vessels may help to avoid potential complications during surgery.

Unilateral duplicated abducens nerve coursing through both the sphenopetroclival venous gulf and cavernous sinus: a case report.

In this anatomy report, we describe the first case of abducens nerve duplication limited to the sphenopetroclival venous gulf and the cavernous sinus. The objective point of division of the two duplicated roots was localized at the gulfar face of the dural porus, just distal to the unique cisternal trunk of the abducens nerve, as it pierced the petroclival dural mater. In the gulfar segment, both roots traveled through a variant of Dorello's canal called the "petrosphenoidal canal" and remained separated through the posterior half of the cavernous sinus. Both roots finally fused in the anterior half of the cavernous sinus to innervate the lateral rectus muscle as a single trunk. Although many variants of the abducens nerve have been reported over the recent decades, this anatomic variation has never been previously described and enriches the continuum of abducens nerve variations reported in the literature data. Awareness of this variation is crucial for neurosurgeons, especially during clival or petrosal surgical approaches used for resection of skull base chordomas.

Correction to: Unilateral duplicated abducens nerve coursing through both the sphenopetroclival venous gulf and cavernous sinus: a case report.

In the Original Publication of the article, one of the references was missed to include. This reference and the text citation are given below.

Lymphatic drainage of lung segments in the visceral pleura: a cadaveric study.

PURPOSE: Although peribronchial lymphatic drainage of the lung has been well characterized, lymphatic drainage in the visceral pleura is less well understood. The objective of the present study was to evaluate the lymphatic drainage of lung segments in the visceral pleura. METHODS: Adult, European cadavers were examined. Cadavers with a history of pleural or pulmonary disease were excluded. The cadavers had been refrigerated but not embalmed. The lungs were surgically removed and re-warmed. Blue dye was injected into the subpleural area and into the first draining visceral pleural lymphatic vessel of each lung segment. RESULTS: Twenty-one cadavers (7 males and 14 females; mean age 80.9 years) were dissected an average of 9.8 day postmortem. A total of 380 dye injections (in 95 lobes) were performed. Lymphatic drainage of the visceral pleura followed a segmental pathway in 44.2% of the injections (n = 168) and an intersegmental pathway in 55.8% (n = 212). Drainage was found to be both intersegmental and interlobar in 2.6% of the injections (n = 10). Lymphatic drainage in the visceral pleura followed an intersegmental pathway in 22.8% (n = 13) of right upper lobe injections, 57.9% (n = 22) of right middle lobe injections, 83.3% (n = 75) of right lower lobe injections, 21% (n = 21) of left upper lobe injections, and 85.3% (n = 81) of left lower lobe injections. CONCLUSION: In the lung, lymphatic drainage in the visceral pleura appears to be more intersegmental than the peribronchial pathway is-especially in the lower lobes. The involvement of intersegmental lymphatic drainage in the visceral pleura should now be evaluated during pulmonary resections (and especially sub-lobar resections) for lung cancer.

Three-dimensional CT angiography of anatomic variations in the pulmonary arterial tree.

PURPOSE: Anatomic variations of the pulmonary arterial tree can cause technical difficulties during pulmonary lobectomy in general and video-assisted thoracic surgery (VATS). Using CT angiography and 3D reconstruction, we sought to identify anatomic variations of the pulmonary arterial tree and assess their respective frequencies. METHODS: We retrospectively studied 88 pulmonary arterial trees in 44 patients having undergone VATS lobectomy for lung cancer over an 18-month period in Amiens University Hospital's Department of Thoracic Surgery. Each CT angiography with 3D reconstruction of the pulmonary arterial tree was performed by two experienced operators, according to a standardized procedure. RESULTS: On the right side, the upper lobe was supplied with blood by a mediastinal artery in 100% of cases and by one or more fissural arteries in 88.6%. The middle lobe was usually supplied by two arteries (54.5%). The upper segment of the right lower lobe was usually supplied by a single artery (90.9%). We identified 11 variations in the vasculature of the basal segments. On the left side, the upper lobe was supplied by four arteries in 50% of cases, three culminal arteries (50%), and a fissural lingular artery (77.3%). The upper segment of the left lower lobe was usually supplied by a single artery (65.9%). We identified 15 anatomic variations in the vasculature of the basal segments. We observed that the origin of the apical artery of the right lower lobe was proximal to the origin of the middle lobe artery in 38.6% of cases. The origin of the apical artery of the left lower lobe artery was proximal to the origin of the lingular fissural artery in 65.9% of cases. CONCLUSION: The findings of the present CT angiography/3D reconstruction study agreed with the reference works on the anatomy of the pulmonary arterial tree and defined the frequency of anatomic variations. It is essential to assess the anatomy of the pulmonary arterial tree before VATS lobectomy.

Anatomical basis of the extended TDAP flap: study of its territories of vascularization and its volume.

INTRODUCTION: The concept of extended thoracodorsal artery perforator (TDAP) flap was described in 2015 for breast reconstruction. Our anatomical study aims to identify the territories vascularised by the thoracodorsal artery perforator via the deep muscular fascial network. The second goal was to define the volume of the extended TDAP flap. MATERIALS AND METHOD: Ten extended TDAP flaps were dissected on 5 fresh human cadavers. Around the classical skin paddle of a TDAP flap, the dissections were performed in a subfascial level, including the muscular fascia and the adipose tissue compartments to increase the volume of the flap. After injection of methylene blue in the thoracodorsal artery, we measured the length and width, the surface and the volume of the coloured flap. RESULTS: The mean sizes of the extended TDAP flap were 24.9 cm × 20.1 cm. The mean surface of the total vascularization zone was 441 cm2. The mean volume of the vascularized flap was 193 ml. CONCLUSION: The thoracodorsal artery perforator via the deep muscular fascial network allows us to harvest a flap of 25 cm × 20 cm with a mean surface of 441 cm² and a mean volume of 193 ml. The extended TDAP flap is a credible option in breast reconstruction.

Anthropometric approach to lumbar vertebral body volumes.

OBJECTIVE: To assess the relationship between the maximum volume of lumbar vertebral bodies and patient morphological features. Knowledge of the volume of the vertebral body is useful when performing vertebroplasty and kyphoplasty. METHODS: 129 patients (18-85 years) were included consecutively over an 8-month period. All had been subject to abdominopelvic CT scans. The weight, height and body mass index (BMI) were known. The volume of each vertebral body was calculated using the formula V = π R (2). H (V = volume, R = radius, H = height). A statistical analysis of the data divided into three groups, men/women, men only and women only, was conducted by calculating the Pearson correlation coefficient. RESULTS: The volume of the vertebral body increased from L1 to L4, but the volume of the L5 vertebral body was lower than that of L3 and L4 in all three groups. The volumes of the vertebral bodies were greater in men than in women. Calculating the correlation coefficient showed that the variable most correlated with volume was patient's height in both the men/women and women-only groups, while the most correlated variable in the male-only group was weight. Vertebral height was the variable most correlated with overall height in all three groups. CONCLUSION: There is a wide variability in the volume of lumbar vertebrae. The volume of the vertebral body appears to vary not only with a person's height but also their weight. The vertebral body seems to expand with weight in men.

Microsurgical anatomy of the Adamkiewicz artery-anterior spinal artery junction.

PURPOSE: The aim of this study is to describe the anterior spinal artery-Adamkiewicz artery (ASA-AKA) junction and establish a classification allowing defining the neurological risk in either thoracoabdominal aorta aneurysm treatment and in anterior or transforaminal thoracolumbar spine surgery. METHODS: Fifteen spinal cords of fresh cadavers were dissected. Both lumbar arteries and ASA were injected with strongly diluted red-colored silicon. RESULTS: The dural crossing of AKA was located on the left side in 86 % of cases, between T8 and T10 in 73.33 % of cases and L1-L2 in 26.67 % of cases. The average diameter of the ascending branch of AKA was 1.10 mm (range 0.8-1.9 mm), and its average length was 30.27 mm (range 12.3-60 mm). The AKA's arch average diameter was 11.3 mm (range 9-20 mm) with an open downward angle average of 20.1° (range 11°-30°). The descending branch of AKA which was a continuation of ASA had an average diameter of 1.33 mm (range 0.8-1.86 mm). The ASA at the top of the arch had an average diameter of 0.74 mm (range 0.2-1.77 mm). According to these findings, we have proposed a new classification with two types of junctions. The type I and its variant correlated to high neurological risk were present in 93.33 % of cases. The type II, correlated to medium or low neurological risk, was present in 6.67 % of cases. CONCLUSION: These anatomical findings allow a planning of the neurological risk before thoracoabdominal aorta aneurysm or thoracolumbar anterior or transforaminal spine surgery.

Optimizing coronary artery opacification and 3D reconstruction from human cadaver hearts in anatomy research.

OBJECTIVE: This study seeks to identify the ideal dilution rate of a radiopaque product to optimize the visualization of coronary arteries and their branches within human cadaver hearts. The process involves obtaining images in the anatomy laboratory and subsequently constructing a three-dimensional model. MATERIALS AND METHODS: We utilized 30 human hearts fixed in 10 % formalin (9 females and 21 males) with a mean age of 79 ± 5 years. The initial experiment, involving the first four hearts (referred to as "group 1"), encountered difficulties in opacifying coronary arteries. In this phase, a probabilistic injection of 20 % Visipaque and 80 % latex, with coronary sinus ostium closure, was performed. The optimal mixture ratio was then determined as 33 % Visipaque and 66 % latex. Recognizing the need for on-site injection at the CT Scan table, this protocol was applied to the subsequent 11 hearts in "group 2." Closure of the coronary sinus was deemed unnecessary. The final 15 hearts, constituting "group 3," revealed that the injection should be gradual, maintaining controlled pressure between 120 and 150 mm Hg. Post-injection, hearts were scanned with the injected coronary arteries using an Optima 660 CT scanner. Two-dimensional images were acquired with parameters set at 64 × 0.625 mm, 100 kV, 300-400 mA, and a rotation of 0.5 s. Subsequently, 3D reconstruction was conducted using Advantage Workstation 4.7 (GE Healthcare) and volume rendering with Volume Viewer software, version 15. RESULTS: Significant differences in the percentage of opacified coronaries were observed among the three groups (p < 0.005). This variation underscores the learning curve and comprehension required before establishing a reliable method. Group 1 (N = 4) demonstrated minimal opacification, group 2 (N = 11) displayed partial opacification, while group 3 (N = 15) achieved 100 % opacification of coronary arteries. CONCLUSION: The successive experiments culminated in the development of a protocol for CT imaging, enabling accurate three-dimensional reconstruction of the normal anatomy of the main and secondary coronary arteries. Our work is grounded in a series of progressively refined and successful experiments.

Influence of age and sex on the thickness of the radial artery wall.

OBJECTIVE: The aim of this study is to investigate whether there is a relationship between age or sex and the thickness of the radial artery wall. MATERIALS AND METHODS: We harvested human radial arteries from 48 cadavers (30 men and 18 women) in the anatomy laboratory. Histological sections of 3 µm thickness were prepared at the Laboratory of Anatomy and Pathological Cytology, mounted on slides, and stained with hematoxylin-phloxine-safran, Masson's trichrome, and orcein. The thickness of each radial artery wall (intima-media thickness) was measured using optical microscopy, and an average measurement was established among the three thicknesses (upper third, middle third, and lower third). STATISTICAL METHODS: Statistical analyses were performed using the R software. Means and standard deviations were utilized. A correlation analysis was also conducted to assess the relationship between radial artery wall thickness and subjects' age. RESULTS: On average, the thickness of the left radial artery wall and that of the right radial artery measured 282 (34) micrometers (µm). We found a correlation between radial artery wall thickness and age in both men (p < 0.001) and women (p < 0.001). CONCLUSIONS: In conclusion, this study elucidates that radial artery wall thickness is related to age and sex in its assessment.

The inter-optic course of a unique precommunicating anterior cerebral artery with aberrant origin of an ophthalmic artery: an anatomic case report.

BACKGROUND AND IMPORTANCE: Some variations of the cerebral arterial circle of Willis, such as an inter-optic course of the anterior cerebral artery are exceedingly rare. Imaging of very rare anatomical features may be of interest. CLINICAL PRESENTATION: In a 67-year-old male individual, the unique precommunicating part of the left anterior cerebral artery was found to course between both optic nerves. There was an agenesis of the right precommunicating cerebral artery. This variation was associated with an aberrant origin of the ophthalmic artery, arising from the anterior cerebral artery. The anatomic features, the possible high prevalence of associated aneurysms of the anterior communicating artery complex as well as implications for surgical planning or endovascular treatments are outlined and embryologic considerations are discussed. CONCLUSION: To the best of our knowledge, this is a very rare illustrated case of an inter-optic course of a unique precommunicating anterior cerebral artery with aberrant origin of an ophthalmic artery.

Anatomical and biometric study of the mitral valve apparatus: application in valve repair surgery.

OBJECTIVE: Most mitral valve repair techniques provide excellent surgical results by removing regurgitation, but all of these techniques simultaneously reduce posterior valve mobility. A comprehensive biometric study of the mitral valve apparatus will provide landmarks that would help improve this posterior valve mobility. MATERIALS AND METHODS: Thirty one (31) human hearts have been studied, from 14 women and 17 men. The characteristics of the studied sample were analyzed descriptively. The difference in means of the variables between women and men were tested using a Student t test. Correlations between the different measures were determined by simple regression analysis. Mean values are shown with ± 1 standard deviation and the limit of significance was set at 0.05. RESULTS: The mean weight of the hearts was 275.3 ± 2.4 g. The anteroposterior diameter of the mitral annulus was 29.3 ± 1.22 mm, the intertrigonal distance was 25.2 ± 3.50 mm and the anterior leaflet to posterior leaflet ratio was 1.9 ± 0.10, the length of the chordae A2 = 19.4 ± 1.15 mm and P2 = 14.5 ± 0.85 mm. The length of the anterior papillary muscle averaged 30.9 ± 7.20 mm and that of the posterior one 30.0 ± 8.75 mm. The comparison of the different values measured between women and men showed no statistically significant difference (p > 0.05). There was no correlation between these different measured values (p > 0.05). CONCLUSION: A perfect knowledge of anatomy and biometry is therefore essential to offer alternative techniques that reproduce the real anatomy and physiology with a complete reconstruction of the mitral valve.

Relationship of the lumbar lordosis angle to the abdominal aortic bifurcation and inferior vena cava confluence levels.

The objective of this study is to determine the relationship of the variations of the lumbar lordosis angle (LLA) to the aortic bifurcation level and inferior vena cava (IVC) confluence level using CT angiography. A retrospective study was conducted using the data available on abdominopelvic CT angiography scans. The LLA, the level and angle of bifurcation of the aorta, the level and angle of confluence of the IVC were identified using multiplanar and 3D reconstruction. Linear regression models were fitted to the data. We interpreted 181 scans for 181 individuals having a mean age of 55 years (18-89). The most common site of aortic bifurcation was at L4-L5 disc space (34.8%) and that of vena confluence was at the upper of L5 (29.3%). The mean LLA was 34.65° (13°-77°). The mean aortic bifurcation angle was 47.43° (17°-100°) and the mean IVC confluence angle was 71.86° (30°-120°). The positions of the aortic bifurcation and venous confluence levels showed a proximal shift with an increasing LLA P < 0.001. This study showed that the level of bifurcation of the aorta and the level of confluence of the IVC may vary with the variations of the LLA.

Microsurgical anatomy of distal medial striate artery (recurrent artery of Heubner).

INTRODUCTION: In literature, many controversies exist about courses and terminology of the distal medial striate artery (DMSA) or recurrent artery first described by Heubner near 1872. The purpose of this study was to define the accurate anatomy of this artery, to help the practitioners during surgery of the anterior cerebral-anterior communicating arteries (ACA-ACoA) complex. MATERIALS AND METHODS: 20 cranial bases were examined using magnification of the surgical microscope. One half for which the internal carotid arteries and internal jugular veins were dissected, cannulated and perfused with colored silicon on fresh cadavers; the other half only with arterial injection of formalin-fixed normal adult human brains. RESULTS: The artery arose principally from A2 segment (58%), always less than 5 mm up to downstream from ACA to ACoA junction. In 59.5% it had a recurrent course anterior to A1 segment. It terminated in one to three stems which entered the medial part of the anterior perforated substance. The DMSA was present as a single vessel in 95% of cases. Its main outer diameter was 0.7 mm and the length had an average of 24 mm. CONCLUSION: Iatrogenic damage or occlusion leads to a mediobasal striatum infarction with important neurological deficits such as brachiofacial hemiparesis and aphasia. This artery should be routinely identified during clipping of ACoA aneurysm. Special attention in this study was given to atypical posterior course or anatomic variations such as double DMSA on a same side.

The article critique as a problem-based teaching method for medical students early in their training: a French example using anatomy.

In France, "article critique" became a particular teaching method in the second part of the medical curriculum. It approaches a reading exercise of scientific medical papers similar to that of journal club. It could be compared to reviewing a paper as performed by reviewers of a scientific journal. We studied the relevancy of that teaching method for the youngest medical students. Our questions were about the understanding and the analyzing ability of a scientific paper while students have just learned basic medical sciences as anatomy. We have included 54 "article critique" written by voluntary students in second and third years of medical cursus. All of the IMRaD structure items (introduction, materials and methods, results and discussion) were analyzed using a qualitative scale for understanding as for analyzing ability. For understanding, 89-96% was good or fair and for the analyzing ability, 93-100% was good or fair. The anatomical papers were better understood than therapeutic or paraclinical studies, but without statistical difference, except for the introduction chapter. Results for analyzing ability were various according to the subject of the papers. This teaching method could be compared to a self-learning method, but also to a problem-based learning method. For the youngest students, the lack of medical knowledge aroused the curiosity. Their enthusiasm to learn new medical subjects remained full. The authors would insist on the requirement of rigorous lessons about evidence-based medicine and IMRaD structure and on a necessary companionship of the students by the teachers.