Surgical and Radiologic Anatomy最新文献

Background: The accessory soleus muscle (ASM) is a rare anatomical variant and the most common accessory muscle in the leg/ankle region. Though asymptomatic in most cases, ASM could exhibit clinical manifestations leading to medical consultation. Since no evidence-based synthesis has been conducted yet, this review aims to collate pooled quantitative data on the clinical presentation and management of ASM.

Methods: The electronic databases of Medline and Embase were searched from inception, met the inclusion criteria. Only clinical cases of symptomatic ASM were included. Clinical and cadaveric incidental findings of ASM were excluded.

Results: Forty-one articles met the inclusion criteria, comprising 134 ASM in 122 patients. The clinical presentation of the ASM was as follows: exertional pain (60%), posteromedial ankle swelling (59%), foot numbness/dysesthesia (5.2%), soft non-tender mass (30%), a tender mass in 9%, a soft mass that becomes hard on plantarflexion (44%), and positive Tinnel's sign (11.2%). The diagnostic modalities used were: x-rays (62.7%), MRI (52.2%), CT scan (24.6%), ultrasound (12.7%) and EMG studies (13.4%). Out of 128 treated cases, conservative management was used in 36.7%, and surgery in 50% of cases including fasciotomy in 22.6%, excision in 20.3%, posterior tibial nerve decompression in 7.8%, and a combined procedure in 1.7%. Regardless of the treatment modality, all surgical patients were satisfied.

Conclusions: The findings of this review would help clinicians to better recognize, diagnose and treat the rare condition of a symptomatic accessory soleus muscle.

The present study aims to describe the morphometric relationship of the subclavian vein and artery to the clavicle and their angular orientation, with a particular focus on improving the safety of interventional procedures by bringing new anatomical landmarks. The costoclavicular region is a critical anatomical corridor where the subclavian vein, subclavian artery, and brachial plexus cords pass beneath the clavicle, partially protected by the subclavius muscle. Precise knowledge of clavicle-vessel relationships is essential, as previous studies have reported considerable variability in the measured distances between the clavicle and adjacent vascular structures, particularly in the context of trauma or surgical fixation. This study aimed to define morphometric parameters to establish a safer anatomical corridor for clinical interventions. A cross-sectional study was conducted using contrast-enhanced computed tomography (CT) scans of adult patients (≥ 18 years). Each clavicle was divided into 13 reference points. At each point, we measured clavicular thickness, the distance from the inferior border of the clavicle to the anterior surface of the subclavian vein and artery, vessel diameters, and the angular relationship between the clavicle and vessels. Side- and sex -related differences were analyzed. A total of 150 participants (75 men, 75 women) were included. All participants were of Hispanic ethnicity, representative of the northeastern Mexican population. The greatest clavicular thickness was observed in men on the right side (14.4 ± 1.6 mm), whereas the shortest distance to the subclavian vein occurred in women on the right side (5.9 ± 2.1 mm). The subclavian vein was significantly larger in men on the right side (14.8 ± 2.7 mm). Significant sex- and side-dependent variations were identified in clavicle dimensions, vessel diameters, and vessel-clavicle distances and angulations. The point of closest proximity between the clavicle and the subclavian vein was consistently located at reference point 3/13 which corresponds to the medial third of the clavicle, located approximately at the costoclavicular region. At this site, the vein was reached at an average depth of ~ 13 mm when the needle was directed 20° cranially relative to the inferior clavicular border. These parameters define a practical "safety cone" that may improve the success and safety of subclavian vein catheterization, particularly in settings where ultrasound guidance is unavailable.

Purpose: Meningohypophyseal trunk (MHT) is a small branch of cavernous part of the internal carotid artery (ICA) which trifurcates into tentorial, inferior hypophyseal and dorsal meningeal arteries. MHT often provides the feeder artery for skull-base meningiomas. Therefore, this arterial trunk is frequently chosen for preoperative embolization. Due to its clinical importance we summarized information about its anatomical variations and relevant clinical attributes pertaining to embolization procedures as reported in literature.

Materials and methods: We performed a systematic review of PubMed and Embase databases according to the PRISMA 2020 guidelines. Studies with anatomical description of the MHT or embolization of this vessel were included.

Results: From 150 identified studies, 49 full-texts were analyzed and 25 of them were included in this systematic review. Seventeen of included studies described morphological features of the MHT (origin from the ICA, complete/incomplete type) and 8 studies depicted embolization of the MHT. The most common origin of the MHT was the posterior loop of the cavernous ICA and in majority of cases complete trifurcated type of the MHT was observed. Embolization of the MHT was successful in nearly all of the patients with lower risk of complications when balloon protection was used.

Conclusions: Relevant morphological details about MHT might facilitate neurosurgeons during planning procedures involving cavernous sinus area but there is no significant correlation between anatomy of the MHT and risk of possible complications. Choice of method and embolic agent during embolization may be approached with customized perspective of the operator. This may be associated with reduced risk of complications and better outcome from clinical viewpoint.

Purpose: There have been no anatomic reports documenting the peripheral segments of the cerebral cortical veins (PSCVs). This study aimed to explore them using magnetic resonance imaging (MRI).

Methods: A total of 100 patients underwent thin-sliced coronal T2-weighted MRI, 2.0 mm in thickness, performed in both the supine and prone positions. For comparison, two cadaveric heads were dissected to observe the PSCVs.

Results: In the dissected hemispheres, the PSCVs were consistently attached to the lateral surfaces of the cerebral gyri. In 100 patients who underwent MRI, the PSCVs were attached variably to the cerebral gyri or bottom of the sulci, in subdivided cerebral areas. The length and thickness of the PSCVs showed high variability. Compared to the medial two-thirds of the middle cerebral part, the PSCVs were more frequently found in the medial two-thirds of the anterior cerebral part. Also, compared to the medial two-thirds of the posterior cerebral region, PSCVs were more frequent in the medial two-thirds of the middle cerebral region. Furthermore, the PSCVs and attached cerebral gyri did not undergo any morphological alterations or displacement in response to positional changes from the supine to the prone position.

Conclusions: PSCVs may be most frequently distributed over the anteromedial cerebral hemisphere, followed by the middle part of the hemisphere. In the cranial cavity, these veins may serve to anchor the cerebral hemisphere floating in the cerebrospinal fluid.

This study constructed a statistical shape model (SSM) of the full ankle joint-including the tibia, talus, calcaneus, and fibula-in healthy Chinese males and analyzed the variation patterns of joint space width (JSW). Computed tomography scans of 108 asymptomatic ankle joints were collected from healthy Chinese males and used to construct a statistical shape model based on principal component analysis. Anatomical variations were evaluated using spatial mapping and least-squares regression. The statistical shape model satisfied the validation criteria for accuracy, compactness, generalization, and specificity, and participants demonstrated high conformity in joint surface coverage and congruency. The first principal component explained more than 22% of the total variance. The minimum joint space widths for the tibiotalar, talofibular, and talocalcaneal joints ranged from 0.85 to 1.95 mm, 0.87 to 2.39 mm, and 0.90 to 3.32 mm, respectively, while the average joint space widths ranged from 2.81 to 3.35 mm, 1.36 to 3.36 mm, and 2.12 to 4.95 mm, respectively. Regression analysis showed that the first five principal modes of variation were strongly correlated with anatomical variations in ankle JSW. This study will provide theoretical support for the early diagnosis and personalized treatment of ankle joint diseases, as well as important morphological references for prosthesis design and biomechanical simulation research.

Purpose: The orbicularis oculi (OOc) and risorius muscles are typically regarded as distinct anatomic and functional units with no known direct muscular connections. Although rare variants of the facial musculature have been reported, their implications for facial dynamics and clinical practice remain underexplored. To the best of our knowledge, this report presents a previously undescribed direct link between the OOc and risorius muscles, highlighting their potential functional and clinical significance.

Methods: This report presents an anatomical variant in which the lateral fibers of the OOc muscle descend abnormally, running lateral to the zygomaticus major and in close proximity to the zygomatic retaining ligaments (McGregor's patch).

Results: In the mid-cheek region, several of these fibers blended with the superior fibers of the risorius muscle, forming a direct muscular connection at the lateral boundary of the facial expression muscles, and ultimately inserting into the modiolus. This bilateral anatomical variant was not accompanied by other notable anomalies in the adjacent facial structures.

Conclusion: This report presents a previously undescribed direct connection between the OOc and risorius muscles. This configuration may allow for coordinated movement between eyelid closure and mouth corner retraction, thereby facilitating complex and integrated facial expressions. Clinically, recognition of this variation is important for procedures such as botulinum toxin injection, musculo-aponeurotic system-based facial surgery, and facial reconstruction, as it may influence both functional and aesthetic outcomes.

Purpose: To demonstrate 3D volumetric computed tomography (CT) analysis of the internal auditory canal (IAC) in a large pediatric population and to evaluate the relationship between age, sex, and IAC mid-point diameters.

Methods: The study population comprised children between 0 and 16 years of age who underwent temporal bone CT. Five males and five females were included in each age group. The IAC mid-point diameters were measured, and a three-dimensional volumetric reconstruction analysis was made. The receiver operating characteristic (ROC) analysis was performed to detect thresholds for the IAC volumes.

Results: A total of 340 ears were evaluated. IAC volume increases with age, most significantly from ages 0-4 to > 4 years. A moderate and significant monotonic increase in IAC volume with age for both the left and right sides were found (r = 0.37, p < 0.001). A ROC analysis revealed that the optimal threshold for the mean IAC volume was 147 mm³. IAC volumes above this threshold indicated a child aged over four years, with an area under the curve (AUC) of 0.76. This threshold yielded a sensitivity of 90% and a specificity of 62%. No significant differences in IAC volume were observed between the right and left sides or between sexes across all age groups.

Conclusion: The current study provides normative 3D volumetric benchmarks for pediatric IAC development, underscoring its accelerated growth in early childhood and supporting anatomical precision in radiological assessment and otologic surgery.