Surgical and Radiologic Anatomy最新文献

Purpose

To describe a case of an anomalous posterosuperior course of the V3 segment of the right vertebral artery (VA) that penetrated the occipital bone (wall of the jugular foramen).

Methods

A 33-year-old healthy woman underwent cranial magnetic resonance (MR) imaging and MR angiography from the upper cervical to the intracranial region using a 3-Tesla scanner to screen for asymptomatic brain lesions, including cerebrovascular diseases.

Results

MR angiography showed no pathological arterial lesions such as aneurysms; however, there was an anomalous posterosuperior course of the V3 segment of the right VA. On MR angiographic source images and coronal reformatted images, the right VA was observed to penetrate the occipital bone lateral to the right hypoglossal canal and is located on the inferoposteromedial wall of the right jugular foramen and enter the posterior fossa at a higher level than the foramen magnum.

Conclusion

We present a case in which the right VA showed an anomalous posterosuperior course at the craniovertebral junction. It is extremely rare for a VA to take a higher course. To our knowledge, this is the first report of such a VA variation in the relevant English-language literature. We speculated that the right VA of our patient was formed by the persistence of one more cephalad primitive artery than the first intersegmental artery, not by the persistence of the primitive hypoglossal artery. Careful observation of MR angiographic source is useful and important for identifying the VA penetrating the occipital bone.

Purpose

The main purpose of this study was to investigate the dimensions of cerebral arteries in the Thai population using digital subtraction angiography (DSA), with a focus on the anterior cerebral artery (ACA), middle cerebral artery (MCA), and posterior cerebral artery (PCA). The research aimed to explore anatomical variations in diameters and lengths of these arteries across different sexes and age groups, which are crucial for cerebrovascular interventions.

Methods

This retrospective study measured the diameters and lengths of the ACA, MCA, and PCA in 177 Thai patients with an average age of 47.6 years (range: 11–82 years) with normal cerebral angiograms. Digital subtraction angiography (DSA) was used for the measurements.

Results

The study found significant sex-based differences in the mean diameters of the left ACA (males: 2.12 ± 0.28 mm, females: 1.92 ± 0.20 mm; p < 0.01), right MCA (males: 2.50 ± 0.25 mm, females: 2.31 ± 0.17 mm; p < 0.01), and left MCA (males: 2.44 ± 0.19 mm, females: 2.30 ± 0.17 mm; p < 0.01) with males exhibiting larger diameters. The right ACA length was significantly longer in males (15.46 ± 1.74 mm) compared to females (13.98 ± 1.92 mm; p < 0.01). While no significant age-related differences were observed in diameters, a significant increase in length with age was noted for the left ACA in the ≥ 60 years group (13.61 ± 1.64 mm) compared to the < 60 years group (12.63 ± 1.36 mm; p < 0.01). Among others, significant correlations were found between the diameters of the left ACA and right MCA (r = 0.699; p < 0.01), and a strong correlation between left ACA length and left PCA diameter (r = 0.975; p < 0.01).

Conclusion

The findings provide invaluable data for tailoring neurosurgical approaches and designing angiographic equipment for the Thai population, emphasizing the importance of considering anatomical variations in clinical practice. These results highlight the necessity for personalized medical care based on anatomical differences to improve cerebrovascular intervention outcomes.

Purpose

There is increasing interest in the use of digital platforms such as ChatGPT for anatomy education. This study aims to evaluate the efficacy of ChatGPT in providing accurate and consistent responses to questions focusing on musculoskeletal anatomy across various time points (hours and days).

Methods

A selection of 6 Anatomy-related questions were asked to ChatGPT 3.5 in 4 different timepoints. All answers were rated blindly by 3 expert raters for quality according to a 5 -point Likert Scale. Difference of 0 or 1 points in Likert scale scores between raters was considered as agreement and between different timepoints was considered as consistent indicating good reproducibility.

Results

There was significant variation in the quality of the answers ranging from extremely good to very poor quality. There was also variation of consistency levels between different timepoints. Answers were rated as good quality (≥ 3 in Likert scale) in 50% of cases (3/6) and as consistent in 66.6% (4/6) of cases. In the low-quality answers, significant mistakes, conflicting data or lack of information were encountered.

Conclusion

As of the time of this article, the quality and consistency of the ChatGPT v3.5 answers is variable, thus limiting its utility as independent and reliable resource of learning musculoskeletal anatomy. Validating information by reviewing the anatomical literature is highly recommended.

Introduction

The structure and function of the human anterolateral abdominal wall have been thoroughly described. However, there has been limited anatomical study of the pyramidalis muscle and its arterial supply. The aim of this study was to analyse the patterns of arterial supply to the pyramidalis in a female population.

Methods

A retrospective study of 32 computed tomography angiography scans of the abdominal wall of adult women was performed to assess the prevalence (bilateral or unilateral presence, or absence), morphology (medial border height, base width and thickness) of pyramidalis and patterns of arterial supply.

Results

Pyramidalis prevalence was bilateral in 75% of computed tomography angiography studies (24/32), unilateral in 6.3% (2/32) and absent in 18.8% (6/32). Of the five patterns of pyramidalis arterial supply observed and described in detail, the most frequent (68%, 34/50 of cases) originated from an exclusive muscular branch of the inferior epigastric artery. Origin from the pubic branch of the inferior epigastric artery was seen in 4% (2/50). There was a single case (2%, 1/50) of artery origin from a variant obturator artery, a common trunk with the pubic branch from the inferior epigastric artery, and from the muscular branch to rectus abdominis. The artery could not be defined in 22% (11/50).

Conclusion

In this computed tomography angiography study of women, five patterns of Pyramidalis arterial supply were identified. In the majority of cases, the pyramidalis derived its arterial supply from an exclusive, isolated muscular branch of the inferior epigastric artery.

Purpose

There have been numerous studies focused on the stiffness of tracheal cartilage. However, no research has been conducted specifically on the annular ligament, nor have any regional differences in the annular ligament been identified. The purpose of this study was to investigate the stiffness of the ligaments present between the thyroid, cricoid and tracheal cartilages.

Methods

The ligaments were identified in the cervical region of living subjects with ultrasonography. The stiffness of the ligaments was measured from the body surface using a digital palpation device (MyotonPRO). Since it is impossible to measure the entire trachea in a living subject, an additional measurement was performed on human cadavers.

Results

Both in vivo and cadaveric investigations found that the stiffness of annular ligaments decreased gradually from the superior to inferior parts. There was no difference in the stiffness between males and females in the superior part of the trachea. However, the stiffness of the middle and inferior parts was predominantly higher in females than in males. Furthermore, males showed significant differences in stiffness between the superior and middle parts, while females showed no significant differences.

Conclusion

These results reveal that there are regional and sex-related differences in the stiffness of human tracheal ligaments.

Purpose

The aim of this study is to define the intramuscular nerve distribution of the sternocleidomastoid muscle (SCM) and the innervation zones (IZ) to describe the optimal botulinum toxin injection sites.

Methods

The cricoid cartilage (CC), laryngeal prominence (LP) and hyoid bone (HB) and angle of mandible (AM) were determined as landmarks. The length of the muscles were measured between the sternoclavicular joint and tip of the mastoid process. SCM was evaluated in two parts as anterior and posterior divided by the line where the length of the muscle was measured. Measurements were made to define the relationships of the SCM with common carotid artery, internal and external jugular veins. IZ were described according to these vessels. Afterwards, Modified Sihler’s staining technique was applied to expose the intramuscular nerve distribution.

Results

The average length of SCM was 160,1 mm. Motor entry point of the accessory nerve fibers were between the AM-HB lines, in the range of 30–40% of the muscle length, and in the posterior part of the muscles. IZ were between the HB-CC lines in the anterior and posterior part. When this interval was examined according to the vessels, the optimal injection sites were between the LP-CC lines.

Conclusions

This study shows the position of the intramuscular nerve fibers endings of the SCM according to the chosen landmarks and the relationship of the IZ with the vessels to prevent complications. These results can be used as a guide for safe and effective botulinum toxin injections with optimal quantities.

Purpose

Little information is known about the mentalis nerve course from the lower lip approximation margin (free margin) to the upper lip. Likewise, no difference in nerve distribution has been observed between the cutaneous and mucosal parts of the lip. Therefore, this study reexamined mentalis nerve morphology.

Methods

For macroscopic observations, three fresh cadavers were dissected (one male and two females; aged 78–93). We also evaluated histological sections obtained from five donated elderly cadavers (two males and three females, aged 82–96 years) and 15 human fetuses (11–40 weeks or crown–rump length 80–372 mm). Immunohistochemical analysis for S100 protein and tyrosine hydroxylase was performed.

Results

In both fetuses and adult cadavers, one to three nerve branches ran upward in the submucosal tissue from the mental foramen. Near the free margin of the lip, some branches passed through the orbicularis oris muscle layer toward the lip skin, whereas others followed a reversed J-shaped course along the free margin. Nerve twigs ran in parallel beneath the mucosa, whereas wavy nerve twigs attached to the basal lamina of the lip epidermis. The difference in nerve endings abruptly occurred at the skin–mucosal junction. Tyrosine hydroxylase-positive sympathetic nerve twigs surrounded arteries and formed a branch composed of S100-negative unmyelinated fibers.

Conclusion

The lower lip skin was innervated by a perforating branch passing through the orbicularis oris muscle, that was different from the lip mucosa. A sudden change in the nerve ending configuration at the mucocutaneous junction seemed to develop postnatally.

Purpose

To report an unusual case of combined Lie’s types A and D of internal carotid artery (ICA) agenesis, diagnosed by magnetic resonance angiography (MRA).

Methods

A 60-year-old woman with dizziness underwent cranial magnetic resonance imaging (MRI) and MRA of the intracranial region for the evaluation of brain and vascular lesions. The magnetic resonance machine was a 3.0-T scanner.

Results

MRI showed no abnormalities, except for multiple small white matter lesions. MRA showed that the left ICA was absent, except for the supraclinoid segment, and an anastomotic vessel was present between the paraclinoid segments of the bilateral ICAs, indicating Lie’s type D ICA agenesis. The left posterior communicating artery (PCoA) was also present. Thus, there were also features of type A ICA agenesis. The anastomotic vessels between the bilateral ICAs and ipsilateral PCoA were relatively small in caliber.

Conclusion

Lie’s type D ICA agenesis usually does not communicate with the anterior and posterior circulations. We encountered a case of combined type D and type A ICA agenesis. To our knowledge, no similar case has been reported in the English literature. This is the second case of type D ICA agenesis with patent ipsilateral PCoA. We speculate that in case of type A ICA agenesis, when the development of the PCoA is insufficient to support collateral blood flow, an anastomotic vessel between bilateral ICAs may develop.

Awareness of unique path of the superficial branch of the radial nerve and its unusual sensory distribution can help avoid potential diagnostic confusion. We present a unique case encountered during a routine dissection of a Central European male cadaver. An unusual course of the superficial branch of the radial nerve was found in the right forearm, where the superficial branch of the radial nerve originated from the radial nerve distally, within the supinator canal, emerged between the extensor digitorum and abductor pollicis longus muscles and supplied the second and a radial half of the third digit, featuring communications with the lateral antebrachial cutaneous nerve and the dorsal branch of the ulnar nerve. Due to dorsal emerging of the superficial branch of the radial nerve the dorsal aspect of the thumb was innervated by the lateral antebrachial cutaneous nerve. To our best knowledge such variation of the superficial branch of the radial nerve has never been reported before. This variation dramatically changes aetiology and manifestation of possible entrapment syndromes which clinicians should be aware of.