Surgical and Radiologic Anatomy最新文献

Purpose: The aim of our study is to report a case of a large fenestrated vertebral artery (FVA) and bilateral duplication of the superior cerebellar artery (SCA) incidentally diagnosed using Computed Tomography Angiography (CTA) and Digital Subtraction Angiography (DSA).

Case presentation: A 63-year-old female patient presenting to the neurology clinic with complaints of dizziness and balance disorder. CTA and DSA revealed a large FVA involving the V3 and V4 segments. Additionally, we observed bilateral duplicated SCAs originating from the distal basilar artery.

Discussion: FVA is a rare anomaly resulting from fusion failure during the embryological period, with a reported incidence of 0.1%. FVA is often (70%) detected in the extracranial region, but it can also occur intracranially at a frequency of approximately 30%. Although various nomenclatures are used in the literature, we identified only two reports of a single fenestration encompassing the V3 and V4 segments, i.e., involving both the extracranial and intracranial regions. While duplication of the SCA is relatively common, bilateral duplication of SCA occurs at a rate of 0.9-5%.

Conclusion: This case report describes an unusual case of VA fenestration involving both extracranial and intracranial segments, along with bilateral duplication of the SCAs. While rare, these findings highlight the importance of recognizing such vascular anomalies, which could be relevant for planning surgical or endovascular procedures in the posterior circulation.

Purpose: Arterial supply of thalamus is complex and highly variable. In particular, the distribution pattern of thalamoperforating arteries received more attention some decades ago than in recent years.

Methods: We are presenting the case of a 46-year-old patient with wake-up drowsiness, complex oculomotor disorder and dysarthria. He was investigated in the acute phase using non-contrast brain Computed Tomography (NCCT), CT Angiography (CTA), and in the following days Digital Subtraction Angiography (DSA) was performed Results. The NCCT showed a subacute ischemic stroke in the right anterior thalamus and rostral midbrain with normal findings on CTA. DSA imaged a variant of thalamic supply (Percheron type III), constituted by perforating branches arising from an artery bridging the P1 segments of both Posterior Cerebral Arteries (PCAs).

Results: The thalamus has a complex and variable arterial supply, mainly in the pattern of paramedian thalamic-mesencephalic perforating arteries. The most reported variant is Percheron type IIb and supplies the paramedian thalami and the rostral midbrain. Type IIb occlusion usually causes a bilateral paramedian thalamic stroke, but rostral midbrain and anterior thalamus are involved in 57% and 19% cases. The rarer Type III variant probably prevented the bilateral extension of infarction and involved the territory of tuberothalamic and paramedian perforating arteries.

Conclusions: Currently, DSA allows directly imaging variants in thalamic vascularization and better understanding the stroke mechanisms. In particular, in the presented case, a medium-sized vessel occlusion rather than a small vessel occlusion mechanism might be raised, leading to a different diagnostic pathway.

Purpose: To date, no non-invasive imaging modality has been employed to profile the structural intricacies of the hippocampal arterial microvasculature in humans. We hypothesised that synchrotron-based imaging of the human hippocampus would enable precise characterisation of the arterial microvasculature.

Methods: Two preserved human brains from, a 69-year-old female and a 63-year-old male body donors were imaged using hierarchical phase-contrast tomography (HiP-CT) with synchrotron radiation at multiple voxel resolutions from 25.08 μm down to 2.45 μm. Subsequent manual and semi-automatic artery segmentation were performed followed by morphometric analyses. These data were compared to published data from alternative methodologies.

Results: HiP-CT made it possible to segment in context the arterial architecture of the human hippocampus. Our analysis identified anterior, medial and posterior hippocampal arteries arising from the P2 segment of the posterior cerebral artery on the image slices. We mapped arterial branches with external diameters greater than 50 μm in the hippocampal region. We visualised vascular asymmetry and quantified arterial structures with diameters as small as 7 μm.

Conclusions: Through the application of HiP-CT, we have provided the first imaging visualisation and quantification of the arterial system of the human hippocampus at high resolution in the context of whole brain imaging. Our results bridge the gap between anatomical and histological scales.

Background: Surgical approaches to the cavernous sinus (CS) and middle cranial fossa (MCF) can be challenging, particularly for young neurosurgeons. The anteromedial (Mullan's) triangle is a triangle by the side of the CS and constitutes part of the floor of the MCF. The contents include the sphenoid sinus, superior ophthalmic vein, and sixth cranial nerve. The literature contains very little research that has precisely defined and measured the anteromedial triangle while considering anatomical variances minimally.

Methodology: The present study was conducted on the skulls of 25 adult human cadavers which were dissected to expose the anteromedial (Mullan's) triangle on both sides. After precisely defining the triangle on each side, measurements of the three borders were taken, and using Heron's formula, the area of each triangle was calculated.

Results: On average, the length of the medial border was 12.5 (+ 3.1 mm); the length of the lateral border was 9.9 (+ 3.1 mm); the length of the base was 10.75 (+ 2.4 mm) and the area of the anteromedial triangle was 43.9 (+ 15.06 mm²).

Conclusion: Precise anatomical knowledge of the Mullan's triangle enables the treatment of disorders in often deformed anatomy or difficult-to-access structures. That is the reason it is important to gain a thorough understanding of the surgical anatomy and to adopt a safe procedure.

Purpose: Ponticulus Posticus, atlantooccipital ligament ossification-induced anomaly, surrounds the vertebral artery and the first cervical nerve root. It is believed to wrap around the first cervical nerve root and the vertebral artery, causing compression. We hypothesized that it would also reduce the diameter of the vertebral artery.

Methods: Between January 1, 2022, and December 31, 2022, cervical spine CT scans taken for any reason were retrospectively reviewed. The images of 1365 patients suitable for evaluation were evaluated by two expert radiologists in 3 dimensions. Among patients with PP, those who underwent cervical angiography were identified for vertebral artery diameter measurement.

Results: The average age of the 1365 individuals included in the study (732 males, 633 females) was 55.78 (± 18.85) with an age range of 1-96. Among this group, PP was detected in 288 individuals, resulting in a total prevalence of 21.1%. Right and left vertebral artery diameters were significantly lower in patients with complete PP compared to the absent group (p < 0,001, p < 0,001, respectively). Additionally, it was observed that width and height diameters and artery diameters were positively correlated in patients with Complete PP.

Conclusions: Ponticulus posticus can cause vertebrobasilar insufficiency by reducing the diameter of the vertebral artery. Therefore, imaging and detailed evaluation of this region are important in symptomatic patients.

Introduction: The facial canal (FC) is an extensive bony canal that houses the facial nerve and occupies a central position in the petrous part of temporal bone. It is of utmost significance to otologists due to its dehiscence and relationship to the inner or middle ear components. The main objectives of current investigation are to detect variations in the reported values ​​of FC anatomy that may occur due to different methodology and to elucidate the influence of age and ethnic factors on the morphological features of FC.

Methods: The methodology is adapted to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Pooled weighted estimation was performed to calculate the mean length, angle, and prevalence of dehiscence.

Results: The cross-sectional shape of FC varied from circular to ellipsoid index and is 1.45 [95% CI, 0.86-2.6]. The mean length of the FC is 34.42 mm [95% CI, 27.62-40.13 mm] and the mean width or diameter is 1.35 mm [95% CI, 1.013-1.63 mm]. The length of the FC in fetuses and children is 21.79 mm [95% CI, 18.44-25.15 mm], and 26.92 mm [95% CI, 23.3-28.3 mm], respectively. In meta-regression, age is observed as a predictor and accounts for 36% of the heterogeneity. The prevalence of FC dehiscence in healthy temporal bones is 29% [95% CI, 20-40%].

Conclusion: The different segments of the FC exhibit significant variability and an unusually high incidence of dehiscence, which could potentially have clinical implications for the etiopathogenesis of facial nerve dysfunction.

Purpose: The current systematic review with meta-analysis aimed to investigate the pooled prevalence of the superior thyroid artery (STA) pattern of origin (distinct or fused-common origin with adjacent arteries in the form of a common trunk). The standard and uncommon variants were also studied, considering the STA's exact surface of origin and the relationship with the upper border of the thyroid cartilage (TC, reference point), considering the laterality effect. Thus, the STA topographical anatomy was considered.

Methods: An evidence-based systematic review with meta-analysis was performed according to the PRISMA 2020 guidelines. A literature search was conducted in four online databases using specific keywords, the pooled prevalence was calculated using statistical analysis in the R programming language, and multiple subgroup analyses were performed.

Results: The most common distinct origin of the STA was from the external carotid artery (ECA) (56.94% pooled prevalence, 95%CI: 50.89-62.89), and the rarest one was from the internal carotid artery (ICA) (< 0.01%, 95%CI: 0.00-0.00). Common trunks were also investigated, with the thyrolingual trunk emanating from the ECA estimated at 0.61% (95%CI: 0.21-1.14), representing the most common. Subgroup analysis based on the nationality, type of study, and sample size, as well as a comparison between left and right sides and males and females, were investigated.

Conclusions: The most common STA origin was estimated as the ECA, the medial surface of origin, and above the TC upper border. Adequate knowledge of STA origin is paramount for surgeons, especially during thyroidectomy, not to cause iatrogenic injury to the external branch of the superior laryngeal nerve.

Purpose: The meniscal vascularization remains poorly documented, particularly its origin. The aim of this cadaveric study was to describe the origin of the arterial vascularization of the menisci.

Methods: This is an anatomical study on human specimens. Twenty knees were used. The average age of the subjects was 82.7 years old (56-97). Ten knees were injected with latex-neoprene and ten knees were injected with colored gelatin mixed with India ink. The same protocol for dissection was used in all cases.

Results: The meniscal vascularization is provided by the genicular arteries of the knee originating from the popliteal artery. The superior medial, superior lateral, inferior medial, inferior lateral, and middle genicular arteries had constant pathways. A second middle genicular artery was found in 55% of cases. The inferior lateral genicular artery ran alongside the meniscal's periphery. The inferior medial genicular artery followed the proximal tibial metaphysis. In all dissections, a previously undocumented small artery originated from under the middle genicular arteries. This artery remained extracapsular and followed the medial meniscal periphery. This artery has been named the "medial capsulo-meniscal artery". The genicular arteries formed an extensive peri-articular anastomotic vascularization for the menisci and thus referred to the "peri-meniscal arterial archs". The lateral peri-meniscal arch was predominantly supplied by the inferior lateral genicular artery, while the medial peri-meniscal arch was mainly supplied by the medial capsulo-meniscal artery.

Conclusion: The peri-meniscal arterial archs are a vascular complex formed by the genicular arteries of the knee and an artery not previously described: the "capsulo-meniscal artery". These archs have a constant presence but their formation and distribution is different between the medial and lateral menisci.

The occipital artery (OA) typically originates from the external carotid artery (ECA). Variations of the ECA has been well described in the current literature, while the OA is a relatively stable vessel, and its variations are uncommon. In the current case report, an aberrant OA has been found coexisting with a linguofacial trunk (LFT) on the right hemineck of a 51-year-old male patient. The OA was identified originating from the cervical internal carotid artery (ICA) at the level of the second cervical vertebra (C2). On the ECA, the lingual and facial arteries were emanating in common, as LFT. The left hemineck of the patient was free of variations. The current coexistence of arterial variants has been reported only once previously; therefore, the current case corresponds to the second case in the English literature. The aberrant OA origin from the ICA has been estimated with a pooled prevalence of 0.37%, while the origin at the C2 level and from the anterior surface of the ICA corresponds to a very rare variation. Additionally, the LFT is one of the most common trunk that can be found on the ECA. Interventional radiologists and surgeons must be aware of common and uncommon variation to avoid iatrogenic lesion.

Purpose: Depending on its axis, pronation varies from the radius rotation around the steady ulna to the reciprocal adduction of the radius and abduction of the ulna. While there is no question that pronator teres is a central pronation agonist, anconeus's role is not settled. The current investigation comparing palpation and ultrasonography in these two muscles during pronation along the axis capitulum-second digit evolved from a serendipitous finding in a clinical anatomy seminar.

Methods: Single-hand palpation and two-transducer ultrasonography over anconeus and pronator teres were used on ten normal subjects to investigate their contraction during pronation around the capitulum-second digit axis. These studies were done independently and blind to the results of the other. The statistical analysis between palpation and ultrasonography was performed with Cohen's kappa coefficient and the χ2 test.

Results: On palpation, on resisted full pronation, anconeus contracted in 8/10 subjects and pronator teres in 10/10 subjects. Without resistance, the corresponding ratios were 5/10 and 9/10. On two-transducer ultrasonography, the comparable ratios were 7/10 and 10/10, and 3/10 and 10/10. A fair concordance (Cohen's kappa = 0.21) between palpation and ultrasonography in detecting the simultaneous status of anconeus and pronator teres during resisted full pronation. Anatomic dissection illustrated the elements involved.

Conclusions: Plain palpation confirmed by ultrasonography showed the simultaneous contraction of anconeus and pronator teres during resisted pronation in most of the studied subjects. The study suggests that palpation can be helpful in directly studying muscle activity during movement.