Caudal Border Research Articles

Chondroitinase ABC combined with Schwann cell transplantation enhances restoration of neural connection and functional recovery following acute and chronic spinal cord injury.

JOURNAL/nrgr/04.03/01300535-202505000-00029/figure1/v/2024-07-28T173839Z/r/image-tiff Schwann cell transplantation is considered one of the most promising cell-based therapy to repair injured spinal cord due to its unique growth-promoting and myelin-forming properties. A the Food and Drug Administration-approved Phase I clinical trial has been conducted to evaluate the safety of transplanted human autologous Schwann cells to treat patients with spinal cord injury. A major challenge for Schwann cell transplantation is that grafted Schwann cells are confined within the lesion cavity, and they do not migrate into the host environment due to the inhibitory barrier formed by injury-induced glial scar, thus limiting axonal reentry into the host spinal cord. Here we introduce a combinatorial strategy by suppressing the inhibitory extracellular environment with injection of lentivirus-mediated transfection of chondroitinase ABC gene at the rostral and caudal borders of the lesion site and simultaneously leveraging the repair capacity of transplanted Schwann cells in adult rats following a mid-thoracic contusive spinal cord injury. We report that when the glial scar was degraded by chondroitinase ABC at the rostral and caudal lesion borders, Schwann cells migrated for considerable distances in both rostral and caudal directions. Such Schwann cell migration led to enhanced axonal regrowth, including the serotonergic and dopaminergic axons originating from supraspinal regions, and promoted recovery of locomotor and urinary bladder functions. Importantly, the Schwann cell survival and axonal regrowth persisted up to 6 months after the injury, even when treatment was delayed for 3 months to mimic chronic spinal cord injury. These findings collectively show promising evidence for a combinatorial strategy with chondroitinase ABC and Schwann cells in promoting remodeling and recovery of function following spinal cord injury.

Minimally-Invasive Robotic-Assisted Resection for Intrathoracic Goiter – A Feasible Alternative to Thoracotomy and Sternotomy

Abstract Background Goiter is a common presentation in daily clinical practice. It usually grows slowly and in rare cases with intrathoracic extension. There is no clear definition of intrathoracic goiters. The incidence in the literature varies from 3% to 7%. Most intrathoracic goiters are localized in the anterior mediastinum, with less than 25% are localized in the posterior mediastinum. This presents a challenge for surgical resection. Traditionally, the intrathoracic portions have been resected via sternotomy for anterior goiters and thoracotomy for posterior goiters. With the increasing use of robotic surgery, new possibilities for minimally invasive surgery and especially robotic procedures have emerged. This may reduce morbidity and length of hospital stay. Aims The study aims to show that minimal-invasive, robotic-assisted resection for intrathoracic goiter is safe and feasible. Methods During the study period from January 2021 to December 2023, 548 thyroid operations were performed in our clinic. All operations were prospectively recorded in the Eurocrine registry and retrospectively analyzed. Goiter was defined as intrathoracic according to perioperative findings (caudal border not visible on sonography and/ or further preoperative investigations ordered). Primary and secondary endpoints were outcome, conversion rate, and incidence of intrathoracic goiter. Results In our clinic, 19/548 patients (3.5%) presented with intrathoracic goiter. 17/19 patients were operated via conventional cervical approach. In 2 patients, minimal-invasive robotic mobilization of the large posterior portion of the goiter was performed in combination with conventional cervical thyroidectomy. No conversion was required. Based on our cases, we present robotic intrathoracic thyroid mobilization as a novel technique to avoid thoracotomy. The rate of recurrent nerve palsy in intrathoracic goiter was 1/28 (3.5%) nerves at risk and occurred with conventional approach. No secondary bleeding or other complications were observed. Conclusion The minimal-invasive robotic approach seems to be a promising alternative to open procedures such as thoracotomy and can reduce morbidity and length of hospital stay.

A Radiation Therapy Contouring Atlas for Delineation of the Level I and II Axillae in the Prone Position: A Single-Institution Experience

With transition from supine to prone position, tenting of the pectoralis major occurs, displacing the muscle from the chest wall and shifting the level I and II axillary spaces. For patients for whom we aim to treat the level I and II axillae using the prone technique, accurate delineation of these nodal regions is necessary. Although different consensus guidelines exist for delineation of nodal anatomy in supine position, to our knowledge, there are no contouring guidelines in the prone position that account for this change in nodal anatomy. The level I and II nodal contours from the Radiation Therapy Oncology Group (RTOG) breast cancer supine atlas were adapted for prone position by 2 radiation oncologists and a breast radiologist based on anatomic changes observed from supine to prone positioning on preoperative diagnostic imaging. Forty-three patients from a single institution treated with prone high tangents from 2012 to 2018 were identified as representative cases to delineate the revised level I and II axillae on noncontrast computed tomography (CT) scans obtained during radiation simulation. The revised nodal contours were reviewed by an expanded expert multidisciplinary panel including breast radiologists, radiation oncologists, and surgical oncologists for consistency and reproducibility. Consensus was achieved among the panel in order to create modifications from the RTOG breast atlas for CT-based contouring of the level I and II axillae in prone position using bone, muscle, and skin as landmarks. This atlas provides representative examples and accompanying descriptions for the changes described to the caudal and anterior borders of level II and the anterior, posterior, medial, and lateral borders of level I. A step-by-step guide is provided for properly identifying the revised anterior border of the level I axilla. The adaptations to the RTOG breast cancer atlas for prone positioning will enable radiation oncologists to more accurately target the level I and II axillae when the axillae are targets in addition to the breast.

Patterns of Failure After Prostate-Only Radiotherapy in High-Risk Prostate Cancer: Implications for Refining Pelvic Nodal Contouring Guidelines

PurposeTo study prostate specific membrane antigen – positron emission tomography (Ga68PSMA-PETCT) based patterns of relapse at biochemical failure (BCF) after prostate-only radiotherapy (PORT) in high-risk (HR) prostate cancer and its implications on pelvic contouring recommendations. Methods and materialsPatients with clinico-radiological high-risk node-negative prostate cancer treated with curative PORT and androgen deprivation therapy (ADT), either within the POP-RT randomised trial or off trial, who underwent a Ga68PSMA-PETCT upon BCF were included. Patterns of regional and distant recurrence on Ga68PSMA-PETCT were studied. Pelvic nodal recurrences were mapped with reference to the superior border of pubic symphysis. Pelvic lymph nodal caudal border (PLNcb) recommendations in the published contouring guidelines (RTOGcb, GETUGcb, PIVOTALcb, NRGcb, GFRUcb) were evaluated. ResultsOf the total 262 patients screened, 68 eligible patients were included (POP-RT trial 35 patients; off-trial 33 patients). Median follow-up was 91 months (IQR, 72–117) and median time to BCF was 65 months (IQR, 49–83). Regional and distant recurrence was seen in 31 (46%) and 31 (46%) patients, respectively. Of the nodal recurrences, nearly half (46%, 14/31) had no distant metastases and 64% (20/31) had a failure in the common iliac nodal region. The lower-most nodal recurrence was 20 mm cranial to the top of pubic symphysis (RTOGcb, GETUGcb, GFRUcb) and 10 mm cranial to the PIVOTALcb. The PLNcb recommended by NRG guideline (NRGcb) had an inter-patient variability of 32 mm, ranging from 16 mm above to 16 mm below the top of pubic symphysis, and the lower most nodal recurrence ranged from 4 mm to 36 mm cranial to NRGcb. ConclusionPelvic failures accounted for a major proportion of recurrences after prostate-only radiotherapy, with the caudal most nodal recurrence being 20 mm cranial to the top of pubic symphysis. This could have implications in defining the caudal border of contouring recommendations.

Optimizing Cervical Target Volume in Patients with Nasopharyngeal Cancer Based On Nodal Drainage Distance.

To determine the potential nodal drainage distances of nasopharyngeal carcinoma (NPC) by investigating spatial distribution of metastatic lymph nodes (LN). Patients with NPC harboring at least two ipsilateral metastatic LNs were enrolled. LN spreading distances were analyzed in nonrestricted direction, cranial-to-caudal direction, and between the two most caudal LNs. Euclidean distance (ED) and vertical distance (VD) between any two LNs were computed. The nearest-neighbor ED and VD covering 95% of LNs or patients (p95-ED and p95-VD) were considered drainage distances, and were further validated by independent internal and external cohorts with recurrent LNs. In all, 5,836 metastatic LNs in 948 patients were contoured. Corresponding to the three scenarios, per-LN level, the p95-EDs were 2.83, 3.28, and 3.55 cm, and p95-VDs were 2.17, 2.32, and 2.63 cm, respectively. Per-patient level, the p95-EDs were 3.25, 3.95, and 3.81 cm, and p95-VDs were 2.67, 2.81, and 2.73 cm, respectively. In internal validation, over 95% of recurred LNs occurred within ED of 2.91 cm and VD of 0.82 cm to the neighbor LN, and the corresponding distances in external validation were 2.77 and 0.67 cm, respectively. In NPC, the maximum LN drainage distance was 3.95 cm without considering the direction. Specifically, in cranial-to-caudal direction, the sufficient vertical drainage distance was 2.81 cm, indicating that a 3-cm extension from the most inferior node may be rational as caudal border of the prophylactic clinical target volume (CTV). These findings promote in-depth understanding of nodal spreading patterns, uncovering paramount evidence for individualized CTV.

COMPARATIVE MORPHOLOGY OF THE PRENATAL DEVELOPMENT OF THE URINARY SYSTEM OF HUMAN AND DOMESTIC PIG (SUS DOMESTICA)

Objective – to determine the peculiarities of the sources of the bookmark and thechronological sequence of topographical and anatomical transformations of the organsand structures of the urinary system of humans and domestic pigs.Materials and methods. The study was performed on 14 series of consecutive histologicalsections of preparations of human embryos and pre-fetuses aged from 4 to 11 weeks ofintrauterine development (UTD) and 8 series of histological sections of preparations ofembryos and pre-fetuses of domestic pigs. For a comparative analysis of the developmentof humans and domestic pigs in UTD, Carnegie stages of prenatal development (CS)were used to periodize embryogenesis. A complex of modern methods of morphologicalresearch (anthropometry, morphometry, microscopy, three- dimensional computerreconstruction, statistical analysis) was used.Results. Skeletotopically, the mesonephros in pig embryos was located between T1and S2 at stages from CS13 to CS16. During the CS19 stage, the cranial border of themesonephros was detected at the level of T2, with further stages continuing to migratefrom CS21 to T7 and from CS23 to L3. The caudal border of the porcine mesonephrosextended to S3 during stages CS19-CS23. When comparing the early stage of human and pig mesonephros development, it wasestablished that at the CS13 stage, the cranial border of the mesonephros was locatedat the T1/T2 level. During further development, the cranial boundary shifted to L4/L5 inhuman embryos, whereas in pig embryos these changes began at CS19, i. e. six stageslater. It was found that the caudal border of the mesonephros in human and pig embryoswas located at S1-S3 throughout development. Thus, human and pig mesonephros hadsimilar, constant caudal borders.During the differential growth of the mesonephros, the mesonephric duct graduallychanged its position from dorsolateral to ventrolateral relative to the mesonephrosin humans at CS16-CS18 stages, and to ventromedial position in pig embryos duringCS16-CS19 stages. These changes in the position of the mesonephric duct indicate thatthe growth process of the mesonephros occurs more intensively in the dorsal part.Conclusions. The use of systematized data on the intrauterine development of pigsallows to optimize the study of normal and pathological development of organs of thegenitourinary system of pigs, which is promising for modeling diseases in humans.

The boundary of posterior to level V region and the theoretical feasibility of irradiation dose reduction of level Va in nasopharyngeal carcinoma

The lymph node involvement in the posterior to level V (PLV) region is mainly observed in nasopharyngeal carcinoma (NPC). Recently, we have reported the distribution of metastatic lymph nodes in the PLV region and there are correlations between the neck node levels (NNL) of NPC, but what is the boundary of the PLV region and how to delineate it remains unclear, and we further to elaborate whether the bilateral level Va should be covered as intermediate-risk nodal regions (CTVn2, about 60 Gy equivalent) for all T and N categories based on these correlations. A total of 1021 consecutive NPC patients with N1-3 stage from January 2012 to December 2020 were reviewed. The lymph node metastasis level of each patient was evaluated according to the updated guidelines proposed in 2013. According to the distribution pattern of lymph node metastasis and the anatomical structure in the PLV region, the boundaries of PLV region was delineated, and whether it is appropriate to cover the bilateral level Va as CTVn2 for all the NPC patients was further discussed. The correlations of level Va with other NNL were studied using logistic regression model. The cranial boundary of PLV region is the caudal border of cricoid cartilage, the caudal boundary is the plane serratus anterior muscle begins to appear, the anterior boundary is the anterior border of trapezius, and the posterior boundary is the convergence of levator scapulae and trapezius. Laterally, the PLV region is limited by the medial edge of trapezius and medially by the lateral surface of levator scapulae. The nodal spread in level Va is based on the lymph node metastasis of level IIb in NPC. The PLV region is a missing NNL of head and neck tumors, especially in NPC. The proposed boundaries of the PLV region can provide a preliminary proposal for the further revision of NNL in head and neck tumors. It is theoretically feasible to reduce the prophylactic irradiation dose of the bilateral level Va in patients with N0 stage or with isolated metastases in level VIIa.

The first report of using endoscopy to evaluate the structure of the internal nasal valve and the measurement of internal nasal valve angle value in Vietnamese people

The objective of this work was to investigate the structural formations and angle of the internal nasal valve (INV) by using nasal endoscopy. A cross-sectional-description study was conducted on one hundred and thirty-nine students of the University of Medicine and Pharmacy without the complaint of chronic nasal obstruction. They were examined the internal nasal areas by using endoscopy two times: before spraying decongestant, and after 15-30 minutes spraying of the decongestant into the nasal cavity to identify the types of the internal nasal valve according to Miman’s classification. The nasal valve angle value was determined by using Autocad software version 2007. The study was done at Can Tho University Hospital. Sharp angle type accounted for 32.01%, blunt angle type accounted for 12.23%, convex caudal border type accounted for 5.04%, concave caudal border type accounted for 5.04%, angle occupied by the septal body accounted for 34.17%, and twisted caudal border type accounted for 11.51% in our study, the average angle of 26°.8 ± 9°.28, with the smallest angle being 9° and the largest angle being 51°. When comparing the rate of internal nasal valve formation for each time in our study and that of Miman, we recognized that there is a difference among rates. Our nasal angle values were similar to those of Asians and different from those of Caucasians. By using endoscopy, we can easily determine the morphology of the internal nasal valve and measure the angle value of the internal nasal valve by using Autocad software version 2007.

Gross and morphometric studies on scapula of Indian elephant

The main objective of the work was to study gross and morphometry of the scapula of Indian elephant. The fore and hind limbs of the elephant were arranged in an almost vertical position under the body, similar to a pillar or leg of a table rather than being in the angular position seen in many other quadruped mammals to support great weight. The aim of this study was to elucidate the osteological outline on the bones of fore limb in Elephants. Three Indian elephants were used, along with some of the specimens available at the Department of Veterinary Anatomy, College of Veterinary Science and Animal Husbandry, Mhow. It was seen that scapula had two surfaces (lateral and medial), three borders (Cranial border, caudal border and dorsal border) and three angles (cranial, caudal and glenoid). The lateral surface was divided into two unequal fossa by a prominent scapular spine. The height of the scapular spine was lowest in the proximal part, but it increased towards the distal part, and was maximum towards near the acromion process. In the medial surface, a large subscapular fossa was present. The dorsal border was formed by the union of lateral and medial surfaces towards the vertebral column.

Some morphological structures and histological features of the gills of Binni (Mesopotamichthys sharpeyi)

This study aimed to describe some morphological and histological aspects of the binni fish's gills. Fifteen adult male binni were pulled alive from the Al-Forat River at about (24 - 28) months, immediately after death. The gills of binni were situated on each side of the head beneath a gill cover; the operculum and the gills were made of finger-like long filaments joined to the cartilaginous gill bar. From each filament, numerous fragile lamellae that resemble leaves protrude. These lamellae comprised tiny capillaries covered in plain squamous epithelial cells. The epithelium acts as a barrier between the fish's blood and the surrounding water. The first, second, third, and fourth pairs of gill arches make up the gills supported by the bone skeleton. Each arch carries a row of gill filaments on its convex side and two rows of gill rakers on its concave side. On the rostral concave border, the filaments in the two extremes of the gill were short, but the length of all the filaments was the same. The first-gill arch's lateral rakers were longer than the medial rakers, while the fourth gill arch's medial rakers were longer than the lateral rakers. The rakers, bony comb-like projections, filled the rostral region of the gill arches at the rostral concave interior side. There was interdigitation between the gill rakers of the neighboring gill arches. Each gill arch included the lateral gill rakers pointing dorsolaterally and medial gill rakers pointing dorsomedially. Filaments originate from the gill arches and are maintained by the cartilage on the caudal convex border of the primary lamellae, from which the secondary lamellae emerge. The simple squamous epithelium lined the secondary lamellae. Keywords: Binni, Gill, Morphology, Histology

Retroperitoneoscopy of the presacral space in horses: Surgical access and anatomy.

Surgical approaches to the equine rectum and perirectal area are described in the literature. However, surgeries in this region can be challenging. To describe the surgical anatomy of the presacral space and to evaluate its access using a retroperitoneoscopic approach. Ex vivo experiment. Preliminary dissections were performed in two cadavers to define the boundaries of the presacral space and to determine portal locations for the surgical approach. After that, nine cadavers were used for experimental presacral retroperitoneoscopic procedure in a standing position. Following retroperitoneoscopy, cadavers were dissected to confirm the anatomical structures observed during the endoscopic procedures, to control the location of each portal and to record iatrogenic trauma. The presacral space was bordered by the vertebral column from the ventral aspect of lumbosacral promontorium to the first coccygeal vertebra dorsally and by the presacral fascia and peritoneum ventrally. Lateral limits were composed of the sacrosciatic ligament and transversalis fascia. Cranial and caudal borders were composed of the peritoneum and coccygeal and levator ani muscles respectively. Retroperitoneoscopic portals were placed between the external anal sphincter and semimembranosus muscles and between the base of the tail and the external anal sphincter muscle through the anococcygeal fascia to enter the space by its caudal border. The retroperitoneal space was reached in all cases and the dorsal and lateral aspects of the rectum were visualised after creation of a working space. Use of cadaver specimens do not permit to evaluate the tolerance in living animals and the surgical complications such as rectal damage, haemorrhage and infection. This study provides an anatomical description and surgical access of the presacral space with a minimal invasive approach. Retroperitoneoscopy allows access to the rectum and the dorsal aspect of the pelvis.

Machine learning can appropriately classify the collimation of ventrodorsal and dorsoventral thoracic radiographic images of dogs and cats.

To determine the feasibility of machine learning algorithms for the classification of appropriate collimation of the cranial and caudal borders in ventrodorsal and dorsoventral thoracic radiographs. 900 ventrodorsal and dorsoventral canine and feline thoracic radiographs were retrospectively acquired from the Picture Archiving and Communication system (PACs) system of the Ontario Veterinary College. Radiographs acquired from April 2020 to May 2021 were labeled by 1 radiologist in Summer of 2022 as either appropriately or inappropriately collimated for the cranial and caudal borders. A machine learning model was trained to identify the appropriate inclusion of the entire lung field at both the cranial and caudal borders. Both individual models and a combined overall inclusion model were assessed based on the combined results of both the cranial and caudal border assessments. The combined overall inclusion model showed a precision of 91.21% (95% CI [91, 91.4]), accuracy of 83.17% (95% CI [83, 83.4]), and F1 score of 87% (95% CI [86.8, 87.2]) for classification when compared with the radiologist's quality assessment. The model took on average 6 ± 1 second to run. Deep learning-based methods can classify small animal thoracic radiographs as appropriately or inappropriately collimated. These methods could be deployed in a clinical setting to improve the diagnostic quality of thoracic radiographs in small animal practice.

Morphology of the soft palate and palatine tonsil of the goat (Capra hyricus).

The present study was carried out to study the morphology of the goat's soft palate and palatine tonsil by gross anatomy, morphometry, light and scanning electron microscopy (SEM). Twelve heads of normal adult (18-24 months) apparently healthy goats of both sexes were collected from local commercial slaughterhouses in Qena Governorate, Egypt. The oral cavity was dissected, and samples were collected for both light and SEM. The soft palate of the goat formed the caudal continuation of the hard palate. It was relatively short, it extended from the level of the caudal border of the last upper molar tooth to terminate caudally against the base of the epiglottis. The oral mucous membrane of the soft palate was covered by non-keratinized stratified squamous epithelium. The lamina propria and submucosa contained connective tissue fibers, diffuse and nodular lymphatic tissue, striated muscle fibers, and a large number of mucous and serous palatine glands. By SEM, the ventral surface had several rounded openings occupied by flower-like structures. These openings represented the entrances to the palatine glands. The palatine tonsil was large and protruded from a fossa in the lateral wall of the oropharynx. It had 2-3 elongated irregular openings that lead to the underlying crypts. These crypts were well-developed and lined by non-keratinized stratified squamous epithelium. The epithelium of the tonsillar crypts directly covered lymphoid tissue and was infiltrated by lymphocytes. Tonsillar glands of pure mucous type were demonstrated. In conclusion, the study provides the basic morphological features of soft palate, as well as the palatine tonsil of the goat by gross observation, light and SEM. The palatine tonsils of goat were well-developed with extensive crypt system, suggesting their essential role in the immunological response against antigens that enter through the oral cavity. The current findings may be useful to understand the role of the palatine tonsil in immunity and disease pathogenesis. RESEARCH HIGHLIGHTS: The study reported the basic morphological features of soft palate and palatine tonsil of goat. The ventral surface of the soft palate had several rounded openings occupied by flower-like structures. The palatine tonsils of goat were well-developed with extensive crypt system. The findings might help to understand the role of the palatine tonsil in immunity and disease pathogenesis.

Gross and histological study of the larynx in red sokoto goat (Capra hircus) from Sokoto, Nigeria

Small ruminants are very important in securing food security and are economically significant in the rural community especially in the west African country. The larynx serves as both airway passage and organ of vocalization, which are associated with their own pathology and diseases. In the current study, 9 specimens of larynxes from apparently healthy red sokoto goats were obtained from Sokoto Modern abattoir, dissected, and morphologically and histologically evaluated. The results showed the larynx is a firm irregular tubular structure situated in between the ramii of the mandible with the laryngeal muscles are intertwined in between the cartilages. The rostral aspect of the larynx forms the caudal border of the pharynx while the caudal end of the larynx continues as the trachea. The thyroid cartilage is the largest while arytenoids are the smallest. Histologically, the thyroid, arytenoids and cricoid are of the hyaline cartilage while the epiglottis is made up of the elastic cartilage. This research work focus on evaluating the gross and microscopic anatomy of the larynx, thus, providing information for future use in both anatomical studies and clinical applications.

Superficial anatomic landmarks can be used to triangulate the location of canine peripheral lymphocentrums: superficial cervical, axillary, and superficial inguinal.

To utilize the geometry of superficial anatomic landmarks to guide incisional location and orientation for peripheral lymphadenectomy, document deep anatomic landmarks for lymphocentrum identification, and develop novel surgical approaches to the superficial cervical, axillary, and superficial inguinal lymphocentrums in dogs. 12 canine cadavers. 2 cadavers were used for a pilot investigation to determine optimal body positioning, select superficial anatomic landmarks for lymphocentrum identification, and evaluate novel surgical approaches to the 3 lymphocentrums. These lymphocentrums were then dissected in 10 additional cadavers using these novel surgical approaches. Measurements of the distances from lymphocentrum to landmark and between landmarks were obtained for each lymphocentrum. Deep anatomic landmarks were recorded for each dissection. The mean and SD were calculated for each measurement and used to develop geometric guidelines for estimating the location of each lymphocentrum for these surgical approaches. Each peripheral lymphocentrum was found in the same location relative to the respective, predetermined, superficial, anatomic boundaries in all cadavers. Briefly, the superficial landmarks to each lymphocentrum were as follows: (1) superficial cervical: wing of atlas, acromion process of scapula, greater tubercle of humerus; (2) axillary: caudal border of transverse head of superficial pectoral muscle, caudal triceps muscle, ventral midline; and (3) superficial inguinal: origin of pectineus muscle, ipsilateral inguinal mammary gland, ventral midline. The proposed superficial and deep surgical landmarks were identified within every cadaver. The previously undescribed surgical approaches were effective for lymphocentrum identification. Anatomic landmarks provided in this study may help reduce surgical time and tissue trauma during peripheral lymphadenectomy in dogs. This study was also the first to describe a surgical approach to the superficial inguinal lymphocentrum and ventral approaches to the superficial cervical and axillary lymphocentrums and provided previously unpublished anatomic landmarks for a lateral approach to the superficial cervical lymphocentrum.

Upper-Neck Versus Whole-Neck Irradiation at the Contralateral Uninvolved Neck in Patients With Unilateral N3 Nasopharyngeal Carcinoma

Upper-neck irradiation (UNI) at the uninvolved neck has shown similar regional relapse-free survival as standard whole-neck irradiation (WNI) in patients with N0-1 nasopharyngeal carcinoma. However, whether UNI at the contralateral uninvolved neck is feasible in unilateral N3 disease, defined as >6 cm and/or below the caudal border of the cricoid cartilage, remains unclear. Data for 291 patients with nasopharyngeal carcinoma with unilateral N3 disease who were treated with intensity modulated radiation therapy from 2009 to 2015 were retrospectively analyzed. Among them, 190 received bilateral WNI (WNI group); the remaining 101 received WNI at the involved neck and UNI at the contralateral uninvolved neck (UNI group). Survival rates were estimated using the Kaplan-Meier method, and differences between groups were compared using the log rank tests. The median follow-up was 79.4 months (interquartile range, 56.0-89.3). Twenty-five patients had regional lymph node relapses (UNI: 10.9%, 11/101 vs WNI: 7.4%, 14/190; P=.31). Of these, 23 patients relapsed within the previously involved neck regions, while only 2 patients had relapses in the contralateral uninvolved neck (1 each in the UNI and WNI groups). Five-year regional relapse-free survival rates were similar between groups (89.7% vs 92.7%, P=.29). Similar between-group findings were also observed for 5-year overall survival (76.1% vs 80.4%, P=.40), distant metastasis-free survival (74.9% vs 79.2%, P=.44), and local relapse-free survival (95.6% vs 94.7%, P=.64). Furthermore, oncologic outcomes in subgroup and multivariable analyses were similar between groups. Regional control and survival outcomes were comparable in UNI at the contralateral uninvolved neck and standard WNI in patients with nasopharyngeal carcinoma with unilateral N3 disease. Our findings provide evidence for future radiation therapy guidelines of nasopharyngeal carcinoma.

Morphological and morphometric studies on the axial skeleton of the sitatunga (Tragelaphus spekii gratus)

BackgroundAnatomical features of the skeleton of wild animals contribute largely to their adaptation. A dearth of information on the skeletal anatomy of the sitatunga (Tragelaphus spekii gratus) necessitated this study. Two adult sitatunga carcasses weighing 54 kg and 57 kg were obtained after post-mortem examination. Bone preparation was achieved through cold water maceration protocol.ResultThe tympanic bulla was elongated and massive, resulting in the rudimentary appearance of the styloid and muscular processes of the temporal bone. The lacrimal bone had a somewhat triangular presentation with the lacrimal foramen on the caudal border of the facial surface while its dorsal border formed the lateral margin of the frontal sinus. There was no observable lacrimal fossa on this facial surface of the lacrimal bone. The facial tubercle was absent. The vertebral column formula was C7 T13 L6 S4 C10-14, and the atlas dorsal median tubercle was smooth, devoid of ridges. The spinous process of the axis extended the entire arch length to hang little above the odontoid process. The thoracic spinous processes were oriented dorso-caudally from T1 to T11; spinous process of T12 was vertical, while that of T13 was oriented dorso-cranially. The length of the transverse process of L1 and L6 were the same, and smaller than the length of those of L2-L5. There was incomplete fusion of sacral spinous processes. Three dorsal and ventral sacral foramina were identified laterally on each side of the vertebrae. The ribs were 26 in number (13 pairs). The sternum was comprised of 5 sternabrae separated by intersternal cartilage. The average number of bones of the axial skeleton was 75. Morphometric in formation included the length of skull, mandible and ribs; body length of vertebrae and spinous process length and height of the vertebrae.ConclusionThis study recorded anatomical features and biometric information on axial skeletal bones of the Sitatunga (Tragelaphus spekii gratus) thereby providing baseline data for future biomedical, archaeological and comparative skeletal anatomical studies.

Morphological Study of Trachea in Swan Goose (Anser cygnoides)

The current investigation was done to study the characteristic anatomical features of the trachea in the swan geese (Anser cygnoides). For that purpose, the methods included using 10 birds (5 males 5 females) collected between October and March. The birds were euthanized, the trachea was collected, and features such as location, relationship, length, weight, and volume were reported. The results revealed that the trachea was located between (caudally) first tracheosyrnigeal cartilage border and (rostrally) in the caudal border of the cricoid cartilage of the larynx. The skeleton of the trachea and each ring of the tracheal cartilages included both broad and narrow regions, with the broad parts of adjacent rings overlapping the narrow parts of the adjacent rings. The trachea was joined to two muscles. Sternotracheolaryngeus muscles, also called sternotrachealis muscles, are a pair of large skeletal muscles securely attached to the trachea at the tenth ring of the distal half, cranial to the pessulus cartilage of the syrinx. They are easy to see, face forward, and come from the craniolateral process of the sternum. This serves as the primary origin of the caudolateral and caudomedial extrinsic muscles of the larynx. This study clearly shows the characteristic features of the trachea of the swan geese that could be useful buildups for future studies that deal with different sciences related to this important bird.

Recommendations of the clinical target volume for the para-aortic region based on the patterns of lymph node metastasis in patients with biliary tract cancer.

Even though the clinical target volume (CTV) in biliary tract cancer (BTC) patients has been proposed by several previous studies, the para aortic CTV for BTC is still not well-defined. The objective of this study was to determine the precise delineation of the para aortic CTV for BTC according to the distribution pattern and failure pattern of lymph nodes. Computed tomography (CT)-, magnetic resonance imaging (MRI)- or positron emission tomography-computed tomography (PET-CT)-generated images of patients with BTC from 2015 to 2020 were analyzed retrospectively. The distribution patterns of lymph nodes in different regions were summarized. The diagnosed para aortic lymph nodes (PALNs) were manually mapped to standard axial CT images. The asymmetric CTV expansions from the para aortic were defined according to the distance from the volumetric centre of lymph node to the most proximal border of aorta. A total of 251 positive lymph nodes were found in the study cohort (n = 61 patients, 92 PALN). All PALNs were projected onto axial CT image of the standard patient. PALNs were concentrated in the 16a2 and 16b1 regions, and the involvement rates were 17% and 13% respectively. Therefore, the upper boundary of 16a2 and the lower boundary of 16b1 were defined as the cranial and caudal border of para aortic CTV, respectively. For the study cohort, the mean distance from the volume center of all lymph nodes in 16a2 and 16b1 to the proximal border of the aorta was 9 mm (range 4-24) in the front, 7 mm (range 3-14) on the left, and 12 mm (range 5-29) on the right. For the validation cohort (n=19 patients, 56 PALN), the mean distance from the center of the lymph node to the border of the aorta were both 10 mm on the left (range 5-20) and right (range 6-23). The mean distance in front of the aorta was 9 mm (range 5-23). Finally, a CTV expansion from the aorta of 18 mm in the front, 12 mm on the left, and 24 mm on the right resulted in 96% (73/76) coverage of PALNs in the study cohort. At the time of the validation, the described CTV could include 96% (47/49) of recurrent PALNs in the validation cohort. The involvement rates of PALNs in 16a2 and 16b1 were the highest. Based on the distribution of PALNs, a new para-aortic CTV was defined to construct a more accurate target volume for adjuvant radiotherapy in BTC.

Potential Metastatic Distance of Lymph Nodes in Different Metastatic Patterns for Nasopharyngeal Carcinoma: Implications for Caudal Border of Elective Nodal Target Volume Delineation

<h3>Purpose/Objective(s)</h3> To investigate the potential metastatic distance of involved lymph nodes (LNs) which can reveal possible pathways of microscopic spread and determine the delineation of caudal border of clinical target volume (CTV) for elective nodal irradiation (ENI) in nasopharyngeal carcinoma (NPC). <h3>Materials/Methods</h3> A total of 1412 patients with pathologically-proven NPC between January 2010 and December 2020 were enrolled. The center points of caudal edge of the most caudally involved LN, lateral process of C1, hyoid bone, cricoid cartilage and cranial edge of sternal manubrium were marked on treatment planning CT scans of each patient. The metastatic distance of the most caudally involved LN, lengths of entire neck, level II, III and IV were determined. Metastatic patterns and their respective metastatic distances covering 95% of patients were analyzed. The metastatic distance covering 95% of patients with LN involvement in lower level is recommended as the caudal border of CTV for patients with involved LN in the upper level. Recommendations in this study were compared with consensus guidelines to propose modifications to caudal border of CTV. <h3>Results</h3> In 1412 patients, lengths of level II, III, IV and II + III ranged widely from 2.9-8.4, 1.6-5.5, 1.2-9.6 and 5.5-12.6 cm, accounting for 21%-62%, 9%-41%, 9%-59% and 41%-91% of the entire neck, respectively. A total of 1933 LNs were delineated, LN metastasis was step by step with 1% skipping rate. Six main metastatic patterns were Level II (498, 25.8%), RPLN + II (801, 41.4%), Level II + III/Va (111, 5.7%), RPLN + Level II + III/Va (327, 16.9%), Level II + III/Va + IV/Vb (58, 3.0%) and RPLN + Level II + III/Va + IV/Vb (119, 6.2%), with significantly different mean metastatic distances. Their maximum distance covering 95% patients were 6.0, 6.3, 8.8, 9.8, 12.8, and 13.7 cm, respectively, based on which, caudal borders for metastatic patterns N0, RPLN, Level II, RPLN + Level II, RPLN + Level II, Level II + III/Va, RPLN + Level II + III/Va were recommended. Compared with current recommendations based on anatomic landmarks, the caudal borders of CTV shifted upward in 175 (99.4%) N0 patients, 88 (98.9%) with metastatic RPLN only and all patients with Level II and RPLN + Level II node involvement by 3.2, 2.9, 6.1, and 5.1 cm. However, 9(15.5%) and 6(5.0%) of patients with level III node involvement had lower recommended caudal borders of ENI than cranial edge of sternal manubrium (Table 1). <h3>Conclusion</h3> Delineation of the caudal border of CTV based on anatomical markers is highly heterogeneous and unstable. This study suggests using the potential metastatic distance (representing the metastatic capacity) of LNs in the lower level as the caudal border of CTV when with involved LN in the upper level. It could reduce the CTV volume in most patients, leading to an expected significant reduction in acute and late toxicity. However, potential metastatic distance in some patients suggests a lower CTV caudal border, indicating the anatomical marker-cased recommendation are insufficient.