Surgical and Radiologic Anatomy最新文献

Purpose: This retrospective study aimed to explore age-related atrophy of the mammillary bodies (MBs) based on their temporal change using magnetic resonance imaging (MRI).

Materials and methods: The study included 30 adult outpatients who presented to the hospital and were followed for more than 100 months with annual MRIs. The bi-ventricular width (BVW), third ventricle width (TVW), and bi-mammillary dimension (BMD) were measured on axial T2-weighted imaging and analyzed.

Results: The 30 patients comprised 1 in their 40s, 5 in their 50s, 6 in their 60s, 11 in their 70s, 5 in their 80s, and 2 in their 90s. The MBs were consistently detected with left-to-right symmetry. The mean BVW was 32 ± 2.2 mm on the initial (BVW1) and 32 ± 2.4 mm on the last (BVW2) MRI. The mean TVW was 7.0 ± 2.3 mm on the initial (TVW1) and 7.6 ± 2.7 mm on the last (TVW2) MRI. Furthermore, the mean BMD was 9.9 ± 1.3 mm on the initial (BMD1) and 10 ± 1.3 mm on the last (BMD2) MRI. Statistically, no age ranges had a large dimension for BVW1, BVW2, TVW1, TVW2, BMD1, or BMD2. Changes between TVW1 and TVW2 were significantly different in the patients in their 80s; changes between BMD1 and BMD2 were not different for any age range or between sexes.

Conclusions: Aging alone does not seem to promote MB atrophy. In healthy brains, the MBs may be stationary structures throughout life.

Background: The platysmal band is created by the platysma muscle, a thin superficial muscle that covers the entire neck and the lower part of the face. The platysmal band appears at the anterior and posterior borders of the muscle. To date, no definite pathophysiology has been established. Here, we observed a lack of knowledge of the anatomy of the platysma muscle using ultrasonography in this study.

Methods: We conducted a descriptive, prospective study observing the platysmal band in resting and contraction states to reveal muscle changes. Twenty-four participants (aged 23-57 years) with anterior and posterior neck bands underwent ultrasonography in resting and contracted states. Ten cadavers were studied aged 67-85 years to measure the thickness of the platysma muscle at 12 points: horizontally (medial, middle, lateral) and vertically (inferior mandibular margin, hyoid bone, cricoid cartilage, superior margin of clavicle).

Results: The anterior and posterior borders of the platysma muscle were thicker than the middle of the platysma muscle when in a contracted state, and the muscle also had a convex shape when contracted. The thickness of the platysma muscle was not significantly different over 12 points in the resting state. During contraction, the platysma muscles contracted in the medial and lateral margins of the muscle, which was more significant in the posterior bands.

Conclusion: The anterior and posterior platysmal bands are related to muscle thickness during contraction. These observations support the change in platysmal band treatment only at the anterior and posterior border of the muscle.

Purpose: The corpus callosum (CC) is the primary interhemispheric connection between the two cerebral hemispheres. Besides their similar morphological characters, there are differences in their measurements. This study aimed to divide the CC into groups using planes based on the anterior commissure (AC) and posterior commissure (PC) and to detect differences in CC magnetic resonance imaging (MRI) and cadaver samples between these groups.

Methods: The study included 80 patients (40 male and 40 female patients) who underwent normal MRI in the midsagittal plane, and 38 cerebral hemispheres from 40 adult cadaver brains, with each hemisected in the midsagittal plane. The medial surface of the CC was divided vertically into three parts (the anterior, middle, and posterior zones) according to the AC and PC. Areas and parameters were measured in both the cadaveric hemispheres and patient MRI images.

Results: The total CC area and CC areas between, anterior, and posterior to the AC-PC vertical lines were the same in both the MRI and cadaver samples. In addition, morphometric measurements like the CC length, AC-PC length, and CC height at the AC and PC vertical lines, and their correlations were also found to be similar between the MRI and cadaver samples.

Conclusion: This study proposes three areas according to AC and PC classification (anterior, middle, and posterior). This new proposed classification is suitable for stereotactic interventions and is useful for obtaining data from MRI images. However, it should be kept in mind that there may be changes and variations.

Background: Rectus capitis lateralis muscle (RCLM) is located at the border between the ventral and dorsal muscle groups, but the nerve topographical anatomy around the muscle is obscure.

Materials and methods: We observed the RCLM in histological sections of 12 midterm and 10 near-term fetal heads (9-18 and 26-40 weeks of gestational age).

Results: At midterm, the RCLM wrapped around the inferiorly protruding inferolateral corner of the cartilaginous occipital bone. The muscle was adjacent to, or even continued to, the intertransversarius muscle between the atlas and axis. At near-term, the jugular process of the occipital bone, that is, the RCLM upper insertion, was either cartilaginous or bony, depending on age. The process formed a collar supporting the internal jugular vein from the inferior side. Moreover, the muscle is tightly attached to or inserted into the venous wall itself. The cartilaginous jugular process was adjacent to Reichert's cartilage, and the uppermost muscle fibers passed through a narrow space between these cartilages. The RCLM appeared to accelerate the jugular process elongation, resulting in complete union of the occipital and temporal bones. The ventral ramus of the first cervical nerve passed between the RCLM and rectus capitis anterior muscle to reach the longus capitis muscle. No nerve passed between the RCLM and the obliquus capitis superior muscle (a muscle at the suboccipital triangle).

Conclusion: The dorsoventral position of the RCLM seemed to correspond to the scalenus posterior muscle in a laminar arrangement of the cervical axial musculature.

Objective: The purpose of the study was to analyze the anatomy and variations in the origin of the dorsal pancreatic artery, greater pancreatic artery and to study the various types of arterial arcades supplying the pancreas on multidetector CT (MDCT).

Methods: A retrospective analysis of 747 MDCT scans was performed in patients who underwent triple phase or dual phase CT abdomen between December 2020 and October 2022. Variations in origin of Dorsal pancreatic artery (DPA), greater pancreatic artery (GPA), uncinate process branch were studied. Intrapancreatic arcade anatomy was classified according to Roman Ramos et al. into 4 types-small arcades (type I), small and large arcades (type II), large arcades (type III) and straight branches (type IV).

Results: The DPA was visualized in 65.3% (n = 488) of cases. The most common origin was from the splenic artery in 58.2% (n = 284) cases. The mean calibre of DPA was 2.05 mm (1.0-4.8 mm). The uncinate branch was seen in 21.7% (n = 106) with an average diameter of 1.3 mm. The greater pancreatic artery was seen in 57.3% (n = 428) predominantly seen arising from the splenic artery. The most common arcade anatomy was of Type II in 52.1% (n = 63) cases.

Conclusion: Pancreatic arterial variations are not very uncommon in daily practice. Knowledge of these variations before pancreatic surgery and endovascular intervention procedure is important for surgeons and interventional radiologist.

Purpose: The ophthalmic artery is often involved in suprasellar and parasellar surgeries, but the anatomical structure where the ophthalmic artery originates has not been fully clarified from the perspective of an endoscopic endonasal approach (EEA).

Methods: A total of 10 fresh cadaveric heads (20 sides) were dissected through an EEA, and the origin of the bilateral ophthalmic arteries and their adjacent structures were observed from a ventral view. The origin of the ophthalmic artery in 50 healthy people was retrospectively studied on computed tomography angiography imaging.

Results: The ophthalmic artery originated from the intradural segment (75%), paraclinoid segment (15%), or parasellar segment (10%) of the internal carotid artery. The cross-sectional view of the internal carotid artery through the EEA showed that the ophthalmic artery originated from the middle 1/3 (75%) or medial 1/3 (25%) of the upper surface of the internal carotid artery. On computed tomography angiography, the ophthalmic artery originated from the middle 1/3 (77%) and medial 1/3 (22%) of the upper surface of the internal carotid artery. All ophthalmic arteries were near the level of the distal dural ring (DDR) of the internal carotid artery, that is, within 3 mm above or below the DDR.

Conclusions: The ophthalmic artery usually originates in the middle 1/3 of the upper surface of the intradural segment of the internal carotid artery within 3 mm of the DDR. The ophthalmic artery can be protected to the utmost extent after its origin is identified through an EEA.

Purpose: As the lenticulostriate arteries (LSAs) perfuse neurologically important areas, it is necessary to accurately assess the origin and number of the LSAs before surgery. Although three-dimensional time-of-flight MR angiography (3D-TOF MRA) is a non-invasive procedure, it requires high-resolution (HR) images to depict the LSAs with a small diameter. Therefore, we performed 3D-TOF MRA with the maximum HR (HR-MRA) using a 3 T scanner to examine whether a good depiction of the LSAs, equivalent to that of digital subtraction angiography (DSA), could be obtained.

Methods: Our study group comprised 16 consecutive patients who underwent HR-MRA and 3D-DSA. In both studies, we evaluated the localization of the origin from M1, M2, or A1 segments, their number of stems, and depiction.

Results: There was no significant difference in the visualization of the LSAs between HR-MRA and 3D-DSA (P values; M1, M2, and A1 = 0.39, 0.69, and 0.69, respectively), and both the number of stems and the localization of the origin of the LSAs corresponded between the two examinations.

Conclusion: HR-MRA at 3 T can depict the LSA well. It reveals the number of the LSA stems and the LSA origin comparatively with DSA.

Introduction: Obturator nerve entrapment or idiopathic obturator neuralgia is an unfamiliar pathology for many physicians which can lead to diagnostic errancy. This study aims to identify the potential compression areas of the obturator nerve to improve therapeutic management.

Material and methods: 18 anatomical dissections of lower limbs from 9 anatomical cadavers were performed. Endopelvic and exopelvic surgical approaches were utilized to study the anatomical variations of the nerve and to identify areas of entrapment.

Results: On 7 limbs, the posterior branch of the obturator nerve passed through the external obturator muscle. A fascia between the adductor brevis and longus muscles was present in 9 of the 18 limbs. The anterior branch of the obturator nerve was highly adherent to the fascia in 6 cases. In 3 limbs, the medial femoral circumflex artery was in close connection with the posterior branch of the nerve.

Conclusion: Idiopathic obturator neuropathy remains a difficult diagnosis. Our cadaveric study did not allow us to formally identify one or more potential anatomical entrapment zones. However, it allowed the identification of zones at risk. A clinical study with staged analgesic blocks would be necessary to identify an anatomical area of compression and would allow targeted surgical neurolysis.

Purpose: Metatarsal fractures often occur around the diaphyseal nutrient foramina (NF) which vary in topography depending on population affinity. Topographical and morphometrical knowledge of the NF is crucial in understanding fracture development and fracture site healing patterns. The current study aimed to describe the topography and the morphometry of the metatarsal diaphyseal NF in South African Africans (SAA), South Africans of European descent (SAED) and South Africans of Mixed Ancestry (SAMA).

Methods: The study examined 4284 dry cadaveric metatarsals from both sexes and sides of these populations for NF topography and morphometry, including the presence, number, location, position, size and direction of the NF on the metatarsal bones.

Results: The NF was present in 99.4% of the metatarsals. Most (84.5%) metatarsals examined had a single NF. Most (97.4%) NF were located in the middle third of the metatarsal bones. The median foramina index (FI) of the second metatarsal exhibited population affinity and significant differences were found both on the left second metatarsal (P = 0.043), and the right second metatarsal (P = 0.046). The position of NF was predominantly lateral on the first (92.4%), second (64.9%) and third (59.1%) metatarsals, whilst the position was predominantly medial on the fifth (65.1%) metatarsals. The NF positions on the fourth metatarsals showed the greatest population variability. The first metatarsals had primarily dominant-sized and distally directed NF whilst the second through fifth had primarily secondary-sized and proximally directed NF.

Conclusion: The topographical anatomy of the metatarsal diaphyseal NF appears similar across the South African populations. Metatarsal bones are highly vascularized bones presenting with multiple nutrient foramina.