Bilateral absence of the deep brachial artery

The aim of the following study was to present and comprehensively describe a case of a bilateral absence of the deep brachial artery (DBA). Furthermore, its embryology and clinical significance will also be discussed. During routine dissection, a 71-year-old male cadaver with a bilateral abnormality in the DBA and its branches was found. The first branch of the brachial artery (BA) was found to be the radial collateral artery, which passed behind the radial nerve. Furthermore, the middle collateral artery originated distal to the radial collateral artery and gave off first a singular, minor muscular branch and then the superior ulnar collateral artery. Later, the preceding nutrient arteries of the humerus and the deltoid branch consecutively branched off from the middle collateral artery. Subsequently, the middle ulnar collateral artery, the inferior ulnar collateral artery, the deltoid artery, the radial artery, and the ulnar artery branched off from the BA, as adapted in the current knowledge regarding the anatomy of the upper extremity. Furthermore, detailed measurements of the distances between the mentioned arteries were carried out. In the present study, a bilateral absence of the DBA was demonstrated. Meta-analysis focusing on the anatomy of this artery has shown how variable its characteristics are. However, our case report is the first in the literature to present this extremely rare variation. Having adequate knowledge regarding the anatomy of the arteries of the proximal arm is of immense importance when performing orthopaedic and reconstructive surgeries in this area.

Gross anatomic relationship between the human left atrial appendage and the left ventricular summit region: implications for catheter ablation of ventricular arrhythmias originating from the left ventricular summit

PURPOSE

The left ventricular summit (LVS) is a source of difficult-to-treat arrhythmias because of anatomical limitations. The aim of this study was to perform detailed research of the left atrial appendage (LAA) anatomy of cadaveric hearts to analyze their complex anatomy and coverage of the LVS.

METHODS AND RESULTS

Eighty human formalin fixed hearts (mean age 44.4 ± 15.5, 27.5% females) were investigated. Each LAA size, type, and its relationship to the LVS were analyzed, as well as possible access sites for mapping/ablating electrode. Four types of LAA were observed over two LVS sites that are either accessible or not. The highest coverage over an inaccessible LVS area was observed in the Broccoli type, followed by the Windsock then the Chicken Wing and finally the Cactus types; over the accessible area of the LVS was observed in the Windsock, then in the Chicken Wing, then in the Cactus, and finally in the Broccoli types. The attainable coverage for electrode access is diminished from 25 to 65% because of the complex pectinate muscles and sharp angles. The highest density of the LAA floor made by pectinate muscles can be found in the Broccoli type (p < 0.005), while the Chicken Wing had the highest number of paper-thin-like pouches.

CONCLUSIONS

The LAA appears to be a promising entry for ablation-qualified patients with the LV summit originate arrhythmias. The complex internal structure of the LAA may complicate ablation procedures. More prominent appendages are promising in more extensive mapping areas over the LVS.

How to write an umbrella review? A step-by-step tutorial with tips and tricks

The number of meta-analyses (MA) and systematic reviews (SR) on various medical issues has increased during the last two decades. The MA and SR results may differ from one another due to a number of factors such as inaccurate or diverse searches through the databases, discrepancies in the extraction process or in statistical analysis, among others. Some results may even contradict one another, resulting in confusion among readers. Umbrella reviews (UR) have allowed the collection of all available data on a medical issue into one concise study, making it the source of evidence-based medical knowledge to the highest degree. Furthermore, UR can resolve those problems by collecting all data and taking into account both MA and SR, making it the superior tool for physicians. Although the pros of UR are clear and the overall popularity of these types of study has increased tremendously, there is no available step-by-step guide on how to conduct one. Therefore, the objective of the present study was to provide researchers with a detailed tutorial on how to conduct an UR. UR represent the next major step in the advancement of evidence-based medicine, with great practical potential for physicians looking for the most up-to-date data on their topic of interest. We hope that our step-by-step guide may be a useful tool for researchers conducting UR in the future.

The occipital-vertebral anastomosis revisited

BACKGROUND

The goal of the study was to provide relevant data about the location and prevalence of the occipital artery-vertebral artery (OA-VA) anastomosis in patients without visible occlusive disease, as well as to thoroughly discuss the clinical significance of these anastomotic channels. Furthermore, the morphometric properties of the OA and its branches were also analysed.

MATERIALS AND METHODS

A retrospective study was carried out to indicate anatomical variations, their prevalence, and morphometrical data on the OA and its branches. The study was performed on 55 randomly selected computed tomography angiographies (CTA) of the head and neck region. Each CTA result was analysed bilaterally. Thus, 110 results were originally assessed.

RESULTS

The OA median maximal diameter was demonstrated at 4.85 mm (lower quartile [LQ]: 4.11; upper quartile [UQ]: 5.53) and the median maximal diameter of VA at 3.60 mm (LQ: 2.79; UQ: 4.38). The distances between OA and its branches were also measured giving a median result of 21.73, 30.29, 60.84, 34.88, 18.02, 55.16 mm for the lower and upper sternocleidomastoid branch, meningeal branch, mastoid branch, and descending branch, respectively. The median distance between OA and its first anastomosis was set to be 51.15 mm (LQ: 37.20; UQ: 60.10). Moreover, a set of additional measurements was carried out in order to create a three-dimensional anatomical heat-map of the occurrence of the OA-VA anastomosis.

CONCLUSIONS

Knowledge about the anatomy of the OA-VA anastomosis might be of immense importance to avoid potentially fatal complications during embolisation of the OA and its branches.

Air spaces of the temporal bone: a morphometric analysis with clinical implications

BACKGROUND

The main objective of the present study was to analyse the morphological variations of the air spaces of the temporal bone, that is, the pneumatized and air-filled spaces of the temporal bone cavities.

MATERIALS AND METHODS

A total of 99 sides were analysed. Temporal bone pneumatic spaces (TBPS) were defined as the free spaces inside the cavities of the temporal bone filled with air, excluding the volume of the structures present in the investigated region. Total volumes of TBPS were calculated as the sum of total volumes of mastoid air cells (MAC), tympanic cavity (TC), and external auditory canal (EAC). Analyses were performed considering the general population and the female and male subgroups.

RESULTS

The overall results obtained on Polish population were set as follows: the median total volume of TBPS was demonstrated at 7882.58 mm3 (lower quartile [LQ]: 6200.56 mm3; higher quartile [HQ]: 10393.16 mm3). The median volume of MAC was set at 5813.05 mm3 (LQ: 4224.94 mm3; HQ: 8181.81 mm3). The median of the total volume of the EAC was demonstrated at 1294.36 mm3 (LQ: 1099.68 mm3; HQ: 1627.84 mm3).

CONCLUSIONS

In the present study, the morphometric properties of the temporal bone cavities were analysed. The results showed that the total volume of the MAC was, on average, lower in women than in men. This should be taken into account when performing procedures on the mastoid, such as mastoidectomies. It is hoped that the results of this study can help reduce potential surgical complications associated with otological procedures.

The cranio-orbital foramen: a meta-analysis with a review of the literature

BACKGROUND

The goal of the present study was to provide accurate data on the prevalence and morphometrical aspects of the cranio-orbital foramen (COF), which can surely be of use by surgeons performing procedures on the lateral orbit. Furthermore, the embryology and the clinical significance of this osseous structure were thoroughly discussed.

MATERIALS AND METHODS

Major online medical databases such as PubMed, Scopus, Embase, Web of Science, and Google Scholar were searched to find all relevant studies regarding COF.

RESULTS

Eventually, a total of 25 studies that matched the required criteria and contained complete and relevant data were included in this meta-analysis. The pooled prevalence of COF was found to be 48.37% (95% confidence interval [CI]: 41.67-55.10%). The occurrence of the COF unilaterally was set to be 71.92% (95% CI: 41.87-96.97%). The occurrence of the COF bilaterally was set at 26.08% (95% CI: 3.03-58.13%).

CONCLUSIONS

In conclusion, we believe that this is the most accurate and up-to- -date study regarding the anatomy of the COF. The COF is prevalent in 48.37% of the cases, and it is most frequently unilateral (73.92%). Furthermore, the prevalence of accessory COFs was found to be 16.72%. The presence of these foramina may represent a source of haemorrhage that ophthalmic surgeons should be aware of when performing procedures in the lateral part of the orbit.

An aberrant right subclavian artery in a 63-year-old male cadaver

An aberrant right subclavian artery (ARSA), also called "arteria lusoria", is described as a right subclavian artery (RSA) with a retro-oesophageal course that most frequently originates as the most distal branch of the aortic arch. The aim of the following study was to present and thoroughly describe a case of an ARSA, its course, branches, and relation to the surrounding anatomical structures and discuss the clinical significance and embryology of this variant. During routine dissection, a 63-year-old male cadaver with an abnormal variant of the RSA was found. The RSA branched off from the aortic arch as the most distal branch. Subsequently, it coursed posteriorly to the trachea and oesophagus at the level of T2 and T3. Abnormalities in the branching pattern of the RSA were also discovered, such as the right vertebral artery originating from the right common carotid artery as its first branch. This study presents a case of an ARSA, which is a rare anatomical variant of the branches of the aortic arch. The course and branching pattern of an aberrant subclavian artery is quite variable, and each variant can be associated with different possible complications. Furthermore, the ARSA is associated with other cardiovascular anomalies, such as the Kommerell's diverticulum. Therefore, knowledge about the possible variations of this anomaly may be of great importance for physicians who encounter this variant in their practice.

Anatomical variations in the first dorsal compartment of the wrist: meta-analysis

BACKGROUND

The first dorsal compartment of the wrist includes tendons of abductor pollicis longus (APL) and extensor pollicis brevis (EPB). However, many studies have showed multiple anatomical variations including anomalies in the number of both APL and EPB tendons and presence of intercompartmental fibro-osseous septum. Unfortunately, studies describing those variations are not consistent, hence, the aim of this study was to provide most accurate data about these anatomical variations in the population, using systematic review and meta-analysis.

MATERIALS AND METHODS

For this purpose, PubMed, Scopus, Web of Science, Embase and a number of minor online libraries were searched. Articles which included exact data about the number of APL or EPB tendons or a presence of intercompartmental septum were qualified for a more precise evaluation. Therefore, out of 1629 studies initially evaluated, 68 were finally included in this meta-analysis. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

A total of 5229 studied wrists have been included in this study. Double APL and single EPB are the most common variations of tendons in the first dorsal compartment, both in cadavers and patients with de Quervain's disease, with no statistically significant differences between those two groups. Presence of intercompartmental fibro-osseus septum is much more common in patients with de Quervain's disease than in cadavers.

CONCLUSIONS

Our results should improve the awareness of anatomical variations in the first dorsal compartment, which in turn should have impact on treatment of de Quervain's disease in clinical practice.

The petroclinoid ligament: a meta-analysis of its morphometry and prevalence of mineralization with a review of the literature

BACKGROUND

The petroclinoid ligament (PCL) is an important structure in the petroclival region. The anatomy of the PCL and its relationship with the surrounding structure is highly variable. The aim of this study was to estimate the morphometry, prevalence of mineralization, and anatomy of the PCL. To achieve this, the authors carried out a meta-analysis, including all studies that report extractable data on the PCL.

MATERIALS AND METHODS

Major online medical databases such as PubMed, Scopus, ScienceDirect, Web of Science, SciELO, BIOSIS, Current Content Connect, Korean Journal Database, and Russian Citation Index were searched to gather all studies regarding the anatomical characteristics, morphometry, and relationship with the anatomical surroundings of the PCL.

RESULTS

A total of 25 studies were included in this meta-analysis. Data were gathered and analysed in eight categories: (1) mineralization of the PCL, (2) relationship of the abducens nerve with the PCL, (3) relationship of the dorsal meningeal artery with the PCL, (4) shape, number, and continuity of the PCL, (5) PCL anterior attachment, (6) PCL anterior attachment point on bone, (7) PCL posterior attachment point on bone, (8) morphometric features of the PCL.

CONCLUSIONS

In conclusion, the authors of the present study believe that this is the most accurate and up-to-date meta-analysis regarding the morphology and mineralization of the PCL. The data provided by the present study may be a useful tool for surgeons performing neurosurgical procedures, such as endoscopic transnasal surgeries. Detailed anatomical knowledge of the petroclival region can surely prevent surgical complications when operating in this area.

The divided zygoma: a meta-analysis of its prevalence with a review of the literature

BACKGROUND

Divided zygoma (DZ) is an important structure in the midfacial region. The anatomy of DZ is poorly researched, but knowledge about this entity could be useful during posttraumatic facial reconstructions. The aim of this study was to estimate the prevalence and anatomy of DZ in different regions around the world. Therefore, the authors performed a meta-analysis, including all studies that report extractable data on the DZ.

MATERIALS AND METHODS

The main online medical databases such as PubMed, EBSCO, ScienceDirect, Web of Science, SciELO, BIOSIS, Current Content Connect, Korean Journal Database and Russian Citation Index, were utilised to gather all studies on anatomical characteristics, prevalence, symmetry, and a number of divisions of zygomatic bone.

RESULTS

A total of 20 studies were included in this meta-analysis. Data were grouped and analysed in five categories: (1) prevalence of DZ bone, (2) prevalence of DZ skulls, (3) gender prevalence of DZ with sides, (4) divisions of zygomatic bone, (5) symmetry of DZ.

CONCLUSIONS

In conclusion, the authors of the present study believe that this study can be considered an up-to-date meta-analysis regarding the prevalence, divisions, and symmetricity of the DZ. The data provided by the present study may be useful information for physicians in recognizing the DZ of the fracture and may be important information during zygomatic bone osteotomy. Detailed anatomical knowledge of the midfacial region can prevent surgical complications when operating in this area.

Variations of coronary sinus tributaries among patients undergoing cardiac resynchronization therapy

BACKGROUND

In cardiac resynchronization therapy, the coronary venous system is used for left ventricular pacing electrode placement. Despite the well-known anatomy of the coronary sinus and its tributaries, heart failure patients' remodeled and enlarged left ventricles may impede the successful lead placement because of acquired anatomical obstacles.

MATERIALS AND METHODS

Fifty-five patients qualified for cardiac resynchronization therapy treatment (CRT) were divided into ischemic and non-ischemic cardiomyopathy. Forty-four control groups without heart failure underwent dual-source computed tomography (CT). Rendered reconstructions of cardiac coronary systems were compared.

RESULTS

The presence of main tributaries was comparable in all groups. The left marginal vein, small cardiac vein, and oblique vein of the left atrium were present in 63%, 60%, and 51% of the hearts in all the groups. CRT referred CT's had significantly longer distances between posterior and lateral cardiac veins over the left ventricle (p < 0.05), wider angles of tributaries (p = 0.03), and smaller lumen of coronary sinus (p = 0.03). In the non-ischemic group, the posterior interventricular and great cardiac veins are more extensive than in the control group. Age-related analysis of vessel size shows a moderate correlation between age and diminishing mean vessel size in all the groups studied.

CONCLUSIONS

The general structure of the coronary heart system is consistent in patients with and without heart failure. The variance of the general structure, or the presence of adequate veins, is an individual variation. The use of CT and analysis of the coronary veins allow better planning of the CRT-D implantation procedure and may reduce the risk of ineffective left ventricular electrode implantation.

Applicability of computed tomography preoperative assessment of the LAA in LV summit ablations

Purpose

Ventricular arrhythmias originating from the left ventricular summit (LVS) may present with challenges for catheter ablation. Recently, the left atrial appendage (LAA) became a new vantage point for mapping and ablating arrhythmias from that region, but data of possible usefulness is limited.

Methods

From September to December 2019, we retrospectively analyzed 48 consecutive patient hearts (20 male; mean age 57.9y ± 11.56) undergoing diagnostic coronary vessel imaging in 64 dual-source computer tomography angiography (CTA). Distances from the LAA to the LVS, LAA shape type, and coronary arteries in the LVS region were measured. Also, we compared the true LVS area from CTA with a calculated formula derived from LVS definition.

Results

The mean LVS area calculated from the formula was 291.58 mm² (± 115.5) while the true area calculated from CT was 263.33 mm² (± 99.49) (p = 0.44). The mean inaccessible area was 133.42 mm² (± 72.89), accessible 95.67 mm² (± 72.77). The mean LAA coverage over LVS was 196.08 mm²—which is approximately 75% of LVS size in general. The most common LAA shape was chicken wing (50%); windsock has the highest accessible area coverage on average (80.23%), followed by chicken wing (59.88%), broccoli (47.72%), and cactus (46.98%). The mean distance from LAA to the surface was 5.14 mm (1.5 to 10 mm) and was not correlated with BMI. LAA has a 98% coverage over the point of transition between the great cardiac vein and anterior interventricular vein.

Conclusion

Angio-CT assessment of the LAA over the LVS structures may be helpful in decision making before an ablation procedure. LAA appears to be a promising mapping approach in LVS arrhythmias.

Middle cerebral artery anatomical variations and aneurysms: a retrospective study based on computed tomography angiography findings

BACKGROUND

Anatomical variations of the middle cerebral artery (MCA) are an important clinical issue, due to high prevalence of intracranial aneurysms. Anatomical variations of vessels can lead to higher shear stress, which is thought to be the main factor leading to aneurysm formation and consequently to higher prevalence of aneurysms. The aim of this study was to evaluate anatomy of the MCA; to classify MCA aneurysms using computed tomography angiography and to correlate anatomical variations of MCA and circle of Willis with prevalence of MCA aneurysms.

MATERIALS AND METHODS

Two hundred and fifty patients without MCA aneurysms and 100 patients with unruptured MCA aneurysms were qualified for the study, with exclusion of patients after MCA clipping. Four aspects of MCA anatomy were evaluated: division point, its relation to the genu, distance to M1 division and the genu and domination of post-division trunks.

RESULTS

Middle cerebral artery bifurcation was found in 86.2% and trifurcation in 13.8% of the cases. 78.4% of MCAs divided before the genu, 19.2% in the genu and 2.4% after the genu. Upper branch domination was seen in 26%, lower branch in 25.4%, middle branch in 4% and no domination in 44.6% of the cases. In the study group 116 aneurysms were found. 86.2% of the aneurysms were located in M1 division point, 6.9% in M2 segment, 3.4% near lenticulostriatae arteries and 3.4% near early cortical branches. The only anatomical variation, which had significantly higher prevalence in patients with left MCA aneurysms, was domination of upper post-division trunk of MCA. No other statistically significant differences in circle of Willis and MCA variations were found between patients with aneurysms and without them.

CONCLUSIONS

The most common configuration of MCA is bifurcation before the genu with no dominating post-division trunk. Incidence of MCA aneurysms is not correlated with anatomical variations of MCA and the circle of Willis.

The scaphocephalic skull of an adult male

The paper presents abnormal craniofacial morphology of an adult male afflicted with premature closure of the sagittal suture. The skull is well preserved and there are no visible traits of surgical management which would be aimed to correctcranial deformation. In consequence of the restricted cranial development, some diameters of the skull were significantly altered. Basically, cranial vault morphology fits apparently to the scaphocephaly, whereas the basic ranium and viscerocranium are altered only in minor degree.

Median nerve thenar motor branch anatomical variations

BACKGROUND

The aim of this study was to determine the prevalence of the different types of median nerve thenar motor branch and to compare them with literature data.

MATERIAL AND METHODS

This study was conducted using median nerves dissected from cadavers stored in a 10% solution of formaldehyde at the Department of Anatomy of Jagiellonian University Medical College (JUMC) and cadavers from the Department of Forensic Medicine JUMC. The research protocol was approved by the Jagiellonian University Ethics Committee (registry KBET/ /209/B/2002).

RESULTS

The studied group comprised 8 (26.7%) women and 22 men (age between 23 and 92 years), yielding a total of 60 thenar motor branches (30 right vs. 30 left). Forty-seven (78.3%) nerves were classified as extraligamentous, 12 (20%) were subligamentous, and 1 (1.7%) was transligamentous. As for the side of origin of the thenar motor branch, in 45 (75%) cases it was the radial side and in 2 (3.33%) cases it was the ulnar side.

CONCLUSIONS

The obtained results confirm that the extraligamentous type of thenar motor branch is the most common and that the ulnar origin of the thenar motor branch is the rarest.

Vascular architecture of the human uterine cervix, as assessed in light- and scanning electron microscopy

BACKGROUND

The aim of this study was to visualise and describe the vasculature of the human uterine cervix.

MATERIAL AND METHODS

The material for this study was obtained from women (age between 20 to 45 years) during autopsy. The material was collected not later than 24 h post-mortem. This study was performed using uteri from cadavers of menstruating nulliparas (33 uteri) and menstruating multiparas (27 uteri). Collected uteri were perfused via the afferent vessels with Mercox resin (for corrosion-casting and SEM assessment) or acrylic paint solution (light microscopy assessment). The research protocol was approved by the Jagiellonian University Ethics Committee (registry KBET/121/8/2007).

RESULTS

In all cases bilateral cervical branches (1-4), originating from the uterine artery, were found. Both in the vaginal and supravaginal parts of the cervix, four distinct vascular zones were found. In the pericanalar zone ran small veins, responsible for draining the mucosal capillaries. Both in the muscular layer, as well as in the pericanalar zone, arterioles, and venules passed close to each other, often adjoining.

CONCLUSIONS

This study does not confirm the existence of a single cervicovaginal artery, but shows that the vascular supply of the cervix comes from several vessels. It also introduces the idea of two systems, responsible for draining blood from the mucosal capillaries. Neither assessment in light microscopy nor in SEM revealed any differences between multiparas and nulliparas, regarding the vascular architecture of the cervix.

Possible compression of the atlantal segment of the vertebral artery in occipitalisation

The current study evaluates the passage of the atlantal segment of the vertebral artery through the atlas to the cranial cavity in the case of occipitalisation, and searches for potential bony obstacles that constrict the lumen of the vertebral artery. Morphometric analysis was performed of the ossified atlanto-occipital articulation of the dry adult male skull, particularly in the region of the posterior arch of the atlas. The distance between the floor of the right groove for the vertebral artery and the occipital bone was measured using a digital sliding caliper. On the left side, measurements of the diameters of the inlet and outlet of the canal for the vertebral artery were performed using the same technique. Fusion of the left portion of the posterior arch of the atlas with the occipital bone caused significant narrowing of the space around the normally existing groove for the vertebral artery, and converted it into the canal. The size of the intracranial opening of the canal for the vertebral artery was measured as 3.8 mm x 4.7 mm, whereas the inlet to the canal was 5.4 mm x 7.0 mm. The diameter of the canal decreases, particularly at the entrance into the cranial cavity; therefore, compression of the vertebral artery within the canal seems to be possible.

Variations in hepatic vascularisation: lack of a proper hepatic artery. Two case reports

The blood supply of the liver and other abdominal organs plays a significant role during abdominal surgery. Knowledge of the most common patterns of vascularisation should be broadened and new anomalies of the celiac trunk and its branches dutifully reported. This paper presents two case reports which describe the lack of a proper hepatic artery. Case 1 describes the cadaver of a 64-year-old female in whom the right hepatic artery was observed to arise from the common hepatic artery and run behind the portal vein. The common hepatic artery was observed to be divided into three terminal vessels: the left hepatic artery, the gastroduodenal artery, and the right gastric artery. Case 2 describes the cadaver of a 75-year-old male with a liver that was supplied from 3 different sources: the left hepatic artery from the left gastric artery (which arose directly from the aorta), the right hepatic artery from the superior mesenteric artery, and the middle hepatic artery from the common hepatic artery - (branch of the hepato-splenic trunk). Moreover, the left inferior phrenic artery arose from the left hepatic artery.

The median nerve in the carpal tunnel

A study of the variations of the course and branching pattern of the median nerve within the carpal tunnel were carried out on 60 wrists from 30 fresh cadavers autopsied in the Department of Forensic Medicine of Jagiellonian University Medical College. The results were compared with the literature. The study confirmed that the extraligamentous type of motor branch variation is most common. The transligamentous course of the nerve is of special importance: it is usually accompanied by hypertrophic muscle, and the nerve hidden within this muscle can easily be cut during transection of the retinaculum. The results proved the necessity of approaching the median nerve from the ulnar side when opening the carpal tunnel.

Geometry of the articular facets of the lateral atlanto-axial joints in the case of occipitalization

This study investigates if atlanto-occipital fusion affects the size and geometrical configuration of the articular facets of the atlanto-axial joint. Morphometric analysis was performed on the male adult skull, the occipital bone of which is assimilated with the first cervical vertebrae (the atlas). The perimeter, Feret's diameter, surface area, and circularity of the inferior articular fa-cets were measured. However, we did not observe significant bilateral differences in size of the inferior articular facets of the assimilated atlas compared to normal first cervical vertebrae. Geometrical conformation of the articular facets of the atlas and axis was assessed using a coordinate measuring machine (PMM - 12106, Leitz). The results obtained from this machine indicated that the inferior articular facets of the assimilated atlas presented asymmetrical orientation compared to the normal anatomy of the atlas. Hence, in the case of occipitalization, the gap between the articulating facets of the atlas and the axis was measured to be greater than in the normal atlanto-axial joint. Computer assisted tomography was applied to visualise the anatomical relationship between the inferior articular facets of the assimilated atlas and the corresponding facets located on the axis. In this case, radiographic examination revealed that the bilaterally articulating facets (inferior and superior) showed disproportion in their adjustment within the lateral atlanto-axial joints. Thus, we concluded that the fusion of the atlas with the occipital bone altered the geometry of the inferior articular facets of the atlas and influenced the orientation of the superior articular facets of the axis.

A case of occipitalization in the human skull

Occipitalization of the atlas is an osseous anomaly of the craniovertebral junction. The aim of this paper is to present an anatomical variant of the fused atlas with the occipital bone and discuss similar cases described in literature. The skull of an adult male analysed in this study belonged to the cranial collection of the Department of Anatomy of the Jagiellonian University, Medical Collage. A tight bony fusion between the anterior arch of the atlas, the left portion of the posterior arch, the lateral masses of the atlas, and the occipital bone was observed. Hence, the left and right superior articular facets of the atlas were fused with the corresponding occipital condyles. The anteroposterior dimension of both inferior articular facets was the same (20 mm), while the transverse diameter of the right one was considerably smaller (12 mm). The transverse diameter of the left inferior articular facets was 17 mm. The right and the left transverse process of the atlas were normally developed, each of them contained transverse foramen, and they were not fused with the occipital bone. The circumference of the foramen magnum was minimally diminished by the osseous structures of the atlas fused to the occipital bone. The sagittal and transverse diameters of the foramen magnum (38 mm x 34 mm) were within the normal range of variation. However, the asymmetrical anatomy of the inferior articular facets of the atlas give rise to speculation that movement in the atlantoaxial joint was disturbed by assimilation with the occipital bone.

An anomalous bilateral muscle in Guyon's canal found during cadaver study

During anatomical dissection, an unusual bilateral muscle in the region of Guyon's canal was found in a 29-year-old human male cadaver. It originated from the pisiform bone and inserted to the flexor retinaculum. The muscle passed between the superficial and deep branch of the ulnar nerve. The ulnar artery passed anteriorly to the muscle. This work reports this finding and tries to categorize it in one of the groups following the literature.

Bilateral ossification of the stylohyoid ligament

This paper presents the case of an adult male skull with bilateral ossification of the stylohyoid complex. The total length of the stylohyoid complex amounts to 62 mm on the left side and 65 mm on the right side. Visual inspection of the stylohyoid revealed the presence of callosities that are located on both stylohyoid complexes at nearly the same level. These sites are regarded as the ossified attachments of the stylohyoid ligaments to the corresponding styloid processes. The skull studied is an example of extreme development of the stylohyoid complex, which could cause severe pain and a restriction of head and neck movement.

The clinical significance of the petroclinoid ligament

This report describes the topography and structure of the petroclinoid ligament with reference to its clinical significance. Observations of this ligament were performed on 24 sections of human heads. Remnants of the ossified form of this ligament were sought in 73 dry human skulls. It was found that the petroclinoid ligament existed as an anterior and posterior fold of the dura mater and stretched from the petrous apex and the anterior and posterior clinoid process respectively. We assessed the close proximity of this ligament to the oculomotor nerve. In one case we found a partially ossified posterior petroclinoid ligament, which appeared as a bony spike that arose posteriorly and inferiorly from the posterior clinoid process.

An atypical position of the foramen ovale

Visual inspection of a dry adult human skull revealed absence of a typical foramen ovale on the left side of the cranial base. The region of the foramen ovale was covered by an osseous lamina, which was continuous with the lateral pterygoid plate and thus formed a wall of an apparent canal, which opened on the lateral side of the pterygoid process. This canal is referred to as an oval canal (canalis ovalis), instead of the foramen ovale. It runs superiorly, medially from the infratemporal fossa, and opens into the middle cranial fossa. The altered osseous morphology of this basicranial region may affect the course of the neurovascular structures which pass through the foramen ovale. As a consequence, clinical symptoms could occur, including paresthesiae of the inner aspect of the cheek and compression and neuralgia of the mandibular nerve or its branches.

The ossified interclinoid ligament

The paper presents an anatomical description of the ossified interclinoid ligament which was found in a male human skull. In the case studied the ossified ligament exists as a bony bridge between the anterior and posterior clinoid processes on the left side of the skull. The length of this connection was measured as 5.0 mm, while its thickness was 3.2 mm. We conjecture that the presence of a considerably thick bony trabecula within the sella region might have had an impact on the course of the internal carotid artery or the oculomotor nerve, causing compression of these structures.

Extraorganic vascular system of adrenal glands in human fetuses

The injection method was used to study the origin and variability of the blood vessels forming the extraorganic vascular system of the adrenal glands. Studies were carried out on 40 human fetuses of a crown-rump length between 113 and 280 mm (14 to 28 weeks of fetal age). It was proved that the arterial blood supply during the fetal period is extremely variable in both the origin and the number of adrenal arteries, as well as in the asymmetry of the blood supply between the left and right adrenal glands. The three main origins of the suprarenal arteries are from the inferior phrenic artery, the abdominal aorta and the renal artery. The inferior phrenic artery is the main one supplying the suprarenal glands during the fetal period. A characteristic feature of the extraorganic venous system in fetal adrenal glands is the constant presence of the adrenal vein, including number, orifice and the main tributaries.

Role of sensory nerves in pancreatic secretion and caerulein-induced pancreatitis

Sensory nerves are implicated in gastroprotection and regulation of visceral circulation but their role in exocrine secretion and pancreatic circulation in intact pancreas and in acute pancreatitis has not been established. We investigated the role of sensory fibers in pancreatic secretion in vivo and amylase release from pancreatic slices (containing nerve fibers) or isolated pancreatic acini, and in caerulein-induced pancreatitis. In conscious rats, the stimulation of sensory nerves by low dose of capsaicin given intraduodenally (0.25-0.5 mg/kg) reduced basal pancreatic secretion, whereas dose of 1 mg/kg increased this secretion. Deactivation of sensory nerves by neurotoxic dose of capsaicin (100 mg/kg over 3 days s.c.) 10 days before tests failed to affect basal secretion but diminished the secretion induced by feeding or the diversion of pancreatic juice. In pancreatic slices, capsaicin (10(-10)-10(-6) M) increased enzyme secretion and this response was abolished by atropine (10(-6) M) or previous deactivation of sensory nerves. In pancreatic acini, capsaicin failed to affect basal and stimulated amylase secretion in response to caerulein or urecholine. In intact rats, stimulatory dose of capsaicin (0.5 mg/kg i.g.) caused about 32% increase of pancreatic blood flow and it was without any effect on the pancreatic DNA synthesis, weight, RNA, DNA and protein content. In contrast, neurotoxic dose of capsaicin caused a reduction (by 27%) in pancreatic blood flow followed by a significant decrease in RNA content and DNA synthesis in pancreatic tissue. Infusion of caerulein (10 g/kg-h) for 5 h produced acute edematous pancreatitis accompanied by over 60% decrease in DNA synthesis, nearly 50% inhibition of pancreatic blood flow, and a significant increase in pancreatic weight, protein content and plasma amylase concentration. Stimulatory dose of capsaicin attenuated the pancreatic tissue damage in caerulein induced pancreatitis, as manifested by a significant reversal of pancreatic blood flow and DNA synthesis decrease. Capsaicin induced inactivation of sensory nerves prior to pancreatitis caused an increase of all parameters of pancreatic damage; pancreatic blood flow dropped by 68%, DNA synthesis decreased by 70%; pancreatic weight, protein content and plasma amylase were also significantly enhanced. We conclude that sensory neurons are involved in the regulation of pancreatic secretion by an indirect mechanism and exhibit a beneficial effect on the pancreatic integrity, mainly due to improving the pancreatic blood flow.