Atavistic and vestigial anatomical structures in the head, neck, and spine: an overview.

Organisms may retain nonfunctional anatomical features as a consequence of evolutionary natural selection. Resultant atavistic and vestigial anatomical structures have long been a source of perplexity. Atavism is when an ancestral trait reappears after loss through an evolutionary change in previous generations, whereas vestigial structures are remnants that are largely or entirely functionless relative to their original roles. While physicians are cognizant of their existence, atavistic and vestigial structures are rarely emphasized in anatomical curricula and can, therefore, be puzzling when discovered incidentally. In addition, the literature is replete with examples of the terms atavistic and vestigial being used interchangeably without careful distinction between them. We provide an overview of important atavistic and vestigial structures in the head, neck, and spine that can serve as a reference for anatomists and clinical neuroscientists. We review the literature on atavistic and vestigial anatomical structures of the head, neck, and spine that may be encountered in clinical practice. We define atavistic and vestigial structures and employ these definitions consistently when classifying anatomical structures. Pertinent anatomical structures are numerous and include human tails, plica semilunaris, the vomeronasal organ, levator claviculae, and external ear muscles, to name a few. Atavistic and vestigial structures are found throughout the head, neck, and spine. Some, such as human tails and branchial cysts may be clinically symptomatic. Literature reports indicate that their prevalence varies across populations. Knowledge of atavistic and vestigial anatomical structures can inform diagnoses, prevent misrecognition of variation for pathology, and guide clinical interventions.

The red ruffed lemur, Varecia rubra (É. Geoffroy Saint-Hilaire, 1812): a comparative morphology investigation of lingual papillae and connective tissue cores.

The morphology of the lingual papillae (filiform, foliate, fungiform, and vallate papillae) and the underlying connective tissue core of the red ruffed lemur (Varecia rubra) of a strepsirrhines species were studied using light and scanning electron microscopy. The filiform papillae distributed at the root of the tongue were larger than the structures distributed at the body and apex. Six to eight vallate papillae were arranged in a Y-shape at the border between the lingual body and the lingual root. Foliate papillae were observed at the posterior lateral border of the tongue. Scanning electron microscopy revealed a primary process and numerous auxiliary processes in the epithelial layer of filiform papillae. After epithelial removal, the connective tissue core of the filiform papilla showed several protrusions surrounding an oval-shaped depression that extended slightly posteriorly, and a large, maple-shaped filiform papilla was seen in the posterior portion of the tongue. The connective tissue cores of the fungiform papillae exhibited a longitudinally ridged cylindrical structure. The connective tissue core of the foliate papillae had numerous tubular projections arranged along a groove with a salivary gland conduit at the base. As a Lemuridae species, the appearance of the fungiform and filiform papillae of the red ruffed lemur is similar to that reported in previous studies of the ring-tailed lemur, with some differences, especially in the filiform papillary connective tissue core at the base and tongue body border. These findings suggest the taxonomic and phylogenetic origins of the lemurs as well as the influence of dietary diversity.

Comparative anatomy of dissected optic lobes, optic ventricles, midbrain tectum, collicular ventricles, and aqueduct: evolutionary modifications as potential explanation for non-tumoral aqueductal anomalies in humans.

PURPOSE: An extensive literature has postulated multiple etiologies for aqueductal stenosis. No publications were found, discussing that evolutionary modifications might explain aqueductal anomalies. This study's objectives were to review the evolutionary modifications of vertebrates' tectum structures that might explain human aqueduct anomalies. Undertaking vertebrate comparative study is currently not feasible in view of limitations in obtaining vertebrate material. Thus, vertebrate material collected, injected, dissected, and radiographed in the early 1970s was analyzed, focusing on the aqueduct and components of the midbrain tectum. METHODS: Photographs of brain dissections and radiographs of the cerebral ventricles and arteries of adult shark, frog, iguana, rabbit, cat, dog, and primate specimens, containing a barium-gelatin radiopaque compound, were analyzed focusing on the aqueduct, the optic ventricles, the quadrigeminal plate, and collicular ventricles. The anatomic information provided by the dissections and radiographs is not reproducible by any other radiopaque contrast currently available. RESULTS: Dissected and radiographed cerebral ventricular and arterial systems of the vertebrates demonstrated midbrain tectum changes, including relative size modifications of the mammalian components of the tectum, simultaneously with the enlargement of the occipital lobe. There is a transformation of pre-mammalian optic ventricles to what appear to be collicular ventricles in mammals, as the aqueduct and collicular ventricle form a continuous cavity. CONCLUSIONS: The mammalian tectum undergoes an evolutionary cephalization process consisting of relative size changes of the midbrain tectum structures. This is associated with enlargement of the occipital lobe, as part of overall neocortical expansion. Potentially, aqueductal anomalies could be explained by evolutionary modifications.

The cavernous carotid inferolateral trunk and persistent primitive maxillary arteries: analysis of dissected arterially injected fetal specimens and high-resolution micro-CT of the dog's anastomotic arteries.

PURPOSE: The presence of a persistent primitive maxillary artery is described in the literature dealing with the development of the cavernous carotid inferolateral trunk, and the relevant similarities of the cranial circulation of the human and dog. The literature includes no dissection photographs of the above-mentioned two human fetal arteries, only diagrammatic representations. This study's objectives were to analyze photographs of fetal dissections for the presence of these two arteries, and also investigate the possibility of obtaining, in preserved dog specimens, high-resolution micro-CT imaging of arteries homologous with the above-mentioned two human arteries. METHODS: The literature describing the embryologic development of the cavernous carotid inferolateral trunk, the persistent primitive maxillary arteries, and their homologies in the dog was reviewed. Relevant dissections of fetal specimens were analyzed. High-resolution micro-CT images of un-dissected dog arteries were produced and analyzed. RESULTS: Photographs of fetal specimen dissections demonstrate the cavernous carotid inferolateral trunk. A separate persistent primitive maxillary artery was not present in the dissected specimens. High-resolution micro-CT images of the dog demonstrate homologous arteries with segments of the human inferolateral trunk, and other skull base and brain arteries. CONCLUSION: This investigation provides the only photographs in the literature of dissected human fetal cavernous carotid inferolateral trunks. A persistent primitive maxillary artery was not present in the dissected specimens and is a non-existent structure, likely a previously misidentified carotid inferolateral trunk. High-resolution micro-CT images of the dog visualized arteries that are homologous to segments of the human cavernous carotid inferolateral trunk artery.

Comparative angiotomographic study of swine vascular anatomy: contributions to research and training models in vascular and endovascular surgery.

BACKGROUND: Medium and large animal models allow researchers to evaluate the efficacy and safety of cardiovascular procedures in systems that resemble human anatomy and can be used to simulate scenarios for training purposes. Although porcine models have been used extensively, many physiological and anatomical features remain unknown or only superficially described. OBJECTIVES: To describe the normal porcine vascular anatomy on computed tomography scans, compare it to human vascular anatomy, and discuss the application of porcine models for open and endovascular procedures. METHODS: Three male Landrace pigs underwent computed tomography. The vascular anatomy of the neck, thorax, abdomen, and limbs was analyzed and described; relevant similarities and differences between porcine and human vascular anatomies and the implications for vascular procedures in pigs are highlighted. RESULTS: The carotid territory, aortic arch, and terminal aorta branches all show marked differences in pigs compared to their human counterparts. Compressions of both left renal and common iliac veins were detected, analogous to those seen in human Nutcracker and May-Thurner syndromes. Vascular measurements (diameters, lengths, and angles) of several different porcine territories are presented. CONCLUSIONS: The data presented should be useful for planning preclinical trials and basic research and for refining surgical training using porcine models in vascular fields.

Estudo de anatomia comparada suína por angiotomografia: contribuições para modelos de pesquisa e treinamento em cirurgia vascular e endovascular / Comparative angiotomographic study of swine vascular anatomy: contributions to research and training models in vascular and endovascular surgery

Resumo Contexto Modelos com animais de médio e grande porte permitem que pesquisadores avaliem a eficácia e a segurança de procedimentos cardiovasculares em sistemas que se assemelham à anatomia humana e podem ser usados para simular cenários para fins de treinamento. Embora modelos suínos tenham sido extensivamente utilizados, muitos fatores fisiológicos e anatômicos permanecem desconhecidos ou apenas superficialmente descritos. Objetivos Descrever a anatomia vascular do suíno por tomografia computadorizada, compará-la à anatomia humana e discutir a aplicação dos modelos porcinos em procedimentos abertos e endovasculares. Métodos Três porcos machos da raça Landrace foram submetidos a tomografia computadorizada. A anatomia vascular de pescoço, tórax, abdome e membros foi analisada e descrita; foram destacadas similaridades e divergências relevantes entre a anatomia vascular de suínos e de humanos e as implicações em procedimentos vasculares nos suínos. Resultados O território carotídeo, o arco aórtico e os ramos terminais da aorta em suínos apresentaram diferenças marcantes quando comparados aos de humanos. Foram detectadas compressões de veias renal e ilíaca comum, ambas à esquerda, semelhantes às encontradas nas síndromes humanas de Nutcracker e May-Thurner. Medidas vasculares (diâmetro, comprimento e ângulos) de diferentes topografias de suínos foram fornecidas. Conclusões Os dados fornecidos podem ser úteis para o planejamento de ensaios pré-clínicos e pesquisa básica, bem como para o refinamento do treinamento cirúrgico usando modelos suínos no campo da cirurgia vascular.

Abstract Background Medium and large animal models allow researchers to evaluate the efficacy and safety of cardiovascular procedures in systems that resemble human anatomy and can be used to simulate scenarios for training purposes. Although porcine models have been used extensively, many physiological and anatomical features remain unknown or only superficially described. Objectives To describe the normal porcine vascular anatomy on computed tomography scans, compare it to human vascular anatomy, and discuss the application of porcine models for open and endovascular procedures. Methods Three male Landrace pigs underwent computed tomography. The vascular anatomy of the neck, thorax, abdomen, and limbs was analyzed and described; relevant similarities and differences between porcine and human vascular anatomies and the implications for vascular procedures in pigs are highlighted. Results The carotid territory, aortic arch, and terminal aorta branches all show marked differences in pigs compared to their human counterparts. Compressions of both left renal and common iliac veins were detected, analogous to those seen in human Nutcracker and May-Thurner syndromes. Vascular measurements (diameters, lengths, and angles) of several different porcine territories are presented. Conclusions The data presented should be useful for planning preclinical trials and basic research and for refining surgical training using porcine models in vascular fields.

An alternative method for the comparative study of coronary vessels: repletion and diaphanization experience in seven animal models / Repleción y diafanización como una alternativa para el estudio comparativo de los vasos coronarios: experiencia en siete modelos animales

Coronary arteries establish a complex blood vessel system, right and left coronary arteries commonly originate from the aortic sinuses and divide into multiple branches that supply the heart with several important variations between species. Diaphanization is a preservative technique which allows internal structures visualization, maintaining the three-dimensionality of the specimen. In this study, human (Homo sapiens), goat (Capra aegagrus hircus), bovine (Bos Taurus), equine (Equus caballus), porcine (Sus scrofa domesticus), canine (Canis lupus familiaris) and feline (Felis silvestris catus) coronary arteries were injected with selfcuring methyl-methacrylate and posteriorly diaphanized. The coronary vasculature was adequately observed in all models while keeping the three-dimensional relation with surrounding cardiac structures, except for septal arteries which were not visualized. As incidental findings, anatomical variations in canine and human hearts were observed. Repletion-diaphanization is a useful blended method to visualize the morphology of superficial coronary arteries. It could be a valuable tool in anatomical teaching and research, but further research needs to be done to prove its effectiveness in different vessel systems.

Las arterias coronarias son un complejo de vasos sanguíneos que usualmente se originan en los senos aórticos y que al dividirse en múltiples ramas suplen los requerimientos metabólicos del tejido cardiaco; cabe aclarar que la anatomía de estas estructuras posee variaciones importantes entre especies. La diafanización es una técnica de preservación que permite observar estructuras internas de un espécimen sin dañar su tridimensionalidad. En este estudio las arterias coronarias del corazón humano (Homo sapiens), caprino (Capra aegagrus hircus), bovino (Bos Taurus), equino (Equus caballus), porcino (Sus scrofa domesticus), canino (Canis lupus familiaris) y felino (Felis silvestris catus), fueron repletadas con metil-metacrilato y posteriormente diafanizados. Se observa la irrigación coronaria de cada uno de los corazones y su relación con las demás estructuras cardiacas, exceptuando las arterias septales. Como hallazgos incidentales se observaron variaciones anatómicas en los corazones canino y humano. Finalmente, esta técnica resultó de utilidad para evaluar la anatomía coronaria, lo que puede ser valioso para educación e investigación. Posteriores investigaciones deben ser realizadas para probar su utilidad en otros sistemas vasculares.

Evaluación anatómica del paladar blando mediante resonancia magnética: Artículo de revisión / Anatomic evaluation of Soft palate using magnetic resonance imaging: Review article

Objetivos: Revisar las publicaciones sobre la anatomía del paladar blando en imágenes de resonancia magnética (RM), para evaluar esta estructura. Contenido: El paladar blando es una estructura anatómica compuesta por músculos con funciones importantes durante la fonación, deglución y la respiración. La resonancia magnética (RM) es una técnica imagenológica que no utiliza radiación ionizante, obteniendo relevancia en los últimos años, por lo que en la actualidad tiene un rol importante en el diagnostico maxilofacial, específicamente en tejidos blandos como el velo del paladar, razón por la cual el odontólogo debe conocer las estructuras y función mediante imágenes de RM. En secuencias rápidas, se pueden evaluar los movimientos del velo del paladar en la deglución y respiración, así como poder observar cambios en las estructuras de la vía aérea superior tal como se da en el síndrome de apnea obstructiva del sueño. Conclusiones: La revisión muestra la importancia de la RM en el estudio de la anatomía del paladar blando; esto debe promover el uso de esta técnica para analizar tejidos blandos. Está demostrado en los diferentes estudios de imágenes por RM que detallan bien estos tejidos en sus diferentes secuencias y tiene como principal ventaja que no utiliza radiación ionizante.

Objectives: This article aims to review the main research about soft palate anatomy and magnetic resonance imaging to evaluate the soft tissues of this structure. Background: Soft palate is an anatomical structure composed of muscles with important functions during phonation, swallowing and breathing. The magnetic resonance is an imaging technique, which does not use ionizing radiation, getting relevance the last few years, so nowadays it plays an important role in maxillofacial diagnosis, especially in soft tissues such as palate veil, a good reason because of dentist specialist must know all about functional magnetic resonance through images in fast sequences where the movements of the veil of the palate in swallowing and breathing can be evaluated, as well as being able to observe changes in the structures of the upper airway as it occurs in obstructive sleep apnea syndrome. Conclusions: The review shows the importance of MRI in the study of the soft palate anatomy; This should promote the use of this technique to analyze soft tissues, it is demonstrated in the different MR imaging studies that detail these tissues well in their different sequences and its main advantage is that it does not use ionizing radiation.

Computed Tomography Staging of Middle Ear Cholesteatoma.

BACKGROUND: To establish computed tomography (CT) staging of middle ear cholesteatoma and assess its impact on the selection of the surgical procedure. MATERIAL/METHODS: Prospective study was conducted on 61 consecutive patients (mean age 26.8 years) with middle ear cholesteatoma. CT scan of the temporal bone and surgery were performed in all patients. CT staging classified cholesteatoma according to its location in the tympanic cavity (T); extension into the mastoid (M); and associated complications (C). Cholesteatoma was staged as stage I (T1, T2), stage II (T3, M1, M2, C1), and stage III (C2). RESULTS: The overall sensitivity of CT staging of cholesteatoma compared to surgery was 88% with excellent agreement and correlation between CT findings and intra-operative findings (K=0.863, r=0.86, P=0.001). There was excellent agreement and correlation of CT staging with surgical findings for T location (K=0.811, r=0.89, P=0.001), good for M extension (K=0.734, r=0.88, P=0.001), and excellent for associated C complications (K=1.00, r=1.0, P=0.001). Atticotympanotomy was carried out in stage I (n=14), intact canal wall surgery was performed in stage II (n=38), and canal wall down surgery was done in stage III (n=5) and stage II (n=4). CONCLUSIONS: We established CT staging of middle ear cholesteatoma that helps surgeons to select an appropriate surgery.

Three-dimensional CT features of occipital squama normal anatomy, anatomic variations and fractures / 中华放射学杂志

Objective To evaluate 3D CT features of normal anatomy,anatomic variations and fractures of occipital squama.Methods The 3D CT features on MIP,VR images were analyzed retrospectively in 589 pediatric cases.The normal anatomy,anatomic variations and fractures of occipital squama were observed respectively,and the differential diagnostic features including the individual location,appearance and extension were analyzed.Results Four hundred and thirty-three patients (75.2％) showed normal anatomy,including 154 patients with adult occipital anatomical features,279 patients with posterior intraoccipital synchondrosis,and 37 patients with Kerckring-supraoccipital synchondrosis.When cases with recent trauma history were excluded,113 patients (19.1％) showed anatomic variants,including unpenetrating sutures and penetrating sutures.The former could be subdivided to Mendosal sutures in 23 cases,superior median fissures in 19 cases,and midline supraoccipital fissures in 4 cases,while the latter could be subdivided to the interparietal bone variations in 54 cases,wormian bones in 23 cases,and accessory bones in 7 cases.Two or more variations coexisted in 33 cases.The occipital squama fractures were shown in 34 cases (5.6％),including linear fractures in 27 cases,comminuted fractures in 3 cases,with depression fracture in one case,separation of cranial sutures in 3 cases,and other fractures associated with variants in 3 cases.The fractures were sharp,or jagged,without limitation of the occification.Conclusion There are different 3D CT features of normal anatomy,anatomic variations and fractures of occipital squama in children,which are important for making the accurate diagnosis.

Research on geometric feature of femoral medullary cavity and it's matching with intramedullary nail / 中华骨科杂志

Objective To investigate the geometric feature of femoral medullary cavity through CT scanning and it's matching with femoral intramedullary nail,and to analysis the reason for difficulties in implanting distal lock pin.Methods Thirty dried femur specimens were measured through CT scanning,and twenty images were taken evenly according to the total length of shaft of femur from each femur.In each image,the data of the central axis point and eight points around medullary cavity wall in X and Y axes were obtained,which were used to reconstruct the three-dimensional models of medullary cavity,central axis,intramedullary nail by computer software.And the models were overlapped for comparison.Then the coronal and sagittal fold line charts for central axis of medullary cavity were drawn.The inserting process of intramedullary nail was simulated to observe whether the nail would punch out of the medullary cavity wall.Results The central axis of femoral medullary cavity and intramedullary nail were overlapped and compared.They matched well in the coronal plane,but the curves of femoral medullary cavity were larger than those of intramedullary nails in sagittal plane.While simulating the inserting process of intramedullary nail,6 nails punched out of the medullary cavity wall in coronal plane (20％,6/30),so did 13 nails in sagittal plane (43％,13/30).Conclusion Intramedullary nails match well with most of the femoral medullary cavities.However,the anatomic structure of the femoral medullary cavity differs individually.Curves of some femoral medullary cavity are large,which can cause deformation of intramedullary nail,and this is the main reason for the failure of distal locking.

Snake heart: a case of atavism in a human being.

Atavism is the rare reappearance, in a modern organism, of a trait from a distant evolutionary ancestor. We describe an apparent case of atavism involving a 59-year-old man with chest pain whose coronary circulation and myocardial architecture resembled those of the reptilian heart. The chest pain was attributed to a coronary steal phenomenon. The patient was discharged from the hospital on a heightened regimen of ß-blockers, and his symptoms improved significantly. To our knowledge, this is only the 2nd reported clinical case of a human coronary circulation similar to that of reptiles.

Accessory fissures of the lung: evaluation with multiplanar reformation on 64-slice spiral CT / 中华放射学杂志

Objective To classify the accessory fissures and assess the frequency of accessory fissures of the lung by 64-slice spiral CT (MSCT). Methods Of 2664 patients, 847 patients were included in this study excluding the patients with pulmonary parenchymal distortion, pleural disease or lobectomy. Allvolume raw data with a slice thickness of 0.6 mm were reformatted in sagittal and coronal orientations with 3 mm thickness and the accessory fissures were assessed. Results A total of 177 accessory fissures in 144 patients (17.0%) were detected. Most of the accessory fissures were incomplete except 10 fissures on the right lung (8.2%) and 2 fissures on the left lung (3.6%) were complete. The most common fissurewas the superior accessory fissure on the right low lobe (n = 112,13.2%) ,followed by the left minor fissure (n= 51,6.0%), the right inferior accessory fissure( n = 6,0. 7% ), the left superior accessory fissure ( n =4, 0.5%), the azygos fissure (n = 3,0.4%) and the accessory fissure on the right upper and middle lobe(n = 1,0.1%). Conclusion 64-slice CT is an efficient method to observe and classify the accessory fissures of the lung with MPR technique and can provide reliable and useful imaging information for the clinician.

Visualization of variations in the pulmonary fissures on multi-planar recontruction images of 64-slice spiral CT / 中华放射学杂志

Objective To observe the variations and distribution of the pulmonary fissures of normal subjects in China on multi-planar recontruction (MPR) images of 64- slice helical CT.Methods A total of 1235 subiects underwent 64- slice helical CT scan with a slice thickness of 0.6 mm.The MPR images were observed to find normal interlobar fissures and the variations including the accessory fissures occurred in lobar or segmental lungs.Results Of the all cases,no variation was seen in 80.08%(989/1235),and pulmonary fissure variations occurred in the remaining 19.92%(246/1235).Among pulmonary fissure variations,20.33% (50 cases) occurred bilaterally,with the other 79.67%(196 cases) unilaterally.Of the unilateral pulmonary fissure variations,63.01%(155 cases) was seen in right lungs,and 16.66% (41 cases)was found in left lungs.There was neither oblique nor horizontal fissure in 1.22%(3 cases) of right lungs.Absence of oblique fissure happened more frequently in left lungs (6.91%,17 cases) than right lungs(3.65%,9 cases).Incomplete oblique fissure happened more frequently in left lungs (8.53%,21 cases)than in right lungs(4.06%,10 cases).Totally,absence of the horizontal fissures were found in 27.24%(67 cases) of the subjects,and incomplete horizontal fissures were found in 9.76% (24 cases).Accessory fissure were found in 83.33%(205 cases) of the subjects,and they happened more frequently in right lungs than in left lungs(53.66%,132 cases on the right,while 29.67%,73 cases on the left).Accessory fissures on right lower lobe and segments happened much more than on the left(40.65%,100 cases on the right,while 7.72%.19 cases on the left).Lingular fissures in the lungs were found in 15.85%(39 cases).The changes in shape and location of the oblique and horizontal fissures were found in 41.06%(101 cases),and happened more frequently in right lungs than left lungs (35.37%,87 cases on the right,5.69%,14 cases on the left).Conclusions Sixty-four-slice helical CT with MPR can clearly display pulmonary fissures and their variations,and it can distinguished small lesions from small vessels.

The experimental study of human liver-split / 中华器官移植杂志

Objective To select a safe and feasible way by comparing the two main styles of splitting liver transplantation classical splitting and modified splitting.Methods In order to compare the distribution of artery, vein and bile duct of all segments of liver, 58 formaldehyde fixed livers and 8 fresh livers were divided into two groups. One group was subjected to classical splitting and the other group to modified splitting. Results Among 66 livers, 66.7?% of the segment VIII and 100?% of the segment V (all or some) drained to middle hepatic vein. In classical splitting group, the vein drainage of 5th and 8th segments of right graft was destroyed.Conclusion Modified splitting is safer and more reliable than classical splitting, so the former is the first choice when the size of donor liver is suitable.

Application of three compartments of mediastinal anatomy in the diagnosis of space-occupying lesions / 中华放射学杂志

Objective To evaluate three compartments of mediastinal anatomy in the diagnosis of space occupying lesions. Methods CT images of 78 mediastinal lesions confirmed by surgery or/and pathology were retrospectively studied. Results According to the occurrence ratio of occupying lesions, anterio superior mediastinal lesions were lymphadenovarix, thymoma, teratoblastoma, and intrathyroma, etc. In anterio inferior mediastinum, heart tumors, teratoblastoma, fatty tumor were found successively. Posterior mediastinal lesions were lymphadenovarix, neurogenic tumors, esophageal tumors, tracheo broncheal tumors, aneurysms, diaphrageal herniation and so on. Conclusion The results suggested that the mediastinal three compartments protocol was more terse and practical than others in the diagnosis of space occupying lesions before operation.

Image research on acetabular teardrop shadow by X-ray plain-film and CT / 中华放射学杂志

Objective To evaluate the anatomical structure of bone in the formation of acetabular teardrop shadow. Methods The acetabular teardrop shadow of the X ray plain film in 100 children and 300 adults, and of CT in 43 cases were analysed 、measured and compared. Results In children, teardrop shadow appeared “U”in 80 00%, 14 00% in teardrop, 6 00% in line. In adult teardrop shadow appeared “U”in 41 33%, 53 33% in teardrop, 5 34% in line. There were significant differences between children and adult in the frequency of “U” and teardrop (? 2=43 34, P

MR angiography appearance of venous sinuses in the region of the torcular Herophili / 中华放射学杂志

Objective To investigate the anatomic appearance in the region of the torcular Herophili by using MR and to evaluate its clinical significance Methods This study involved 123 healthy subjects All subjects underwent initial T 1W and T 2W MR examination in order to exclude intracranial occupying disease and vascular malformation Then, images of venous sinuses were obtained in the region of the torcular Herophili 72 of these subjects were examined with coronal 2D TOF MR venography (MRV), 44 cases were examined with coronal 3D PC angiography, and other 7 volunteers were examined with both of the two aforementioned methods Results (1) The venous drainage dominance showed mainly to the right side in 84 cases, mainly to the left side in 23 cases, equal drainage in 16 cases (2) According to the relation among the sinuses in the region of the torcular Herophili, all subjects in this study could be grouped into 4 types: Type 1, including those subjects in which a confluence of sinuses existed or the superior sagittal sinus and the straight sinus forked, and the forking of both sinuses joined to form the lateral sinuses Type 2, including those subjects in which the sagittal sinus drained into one side and the straight sinus drained into the other Type 3, including those subjects in which the superior sagittal sinus and the straight sinus joined and mainly drained into the right side Type 4, including those subjects in which the superior sagittal sinus and the straight sinus joined and mainly drained into the left side Conclusions MR angiography provides a useful method to show the anatomic features in the region of the torcular Herophili The pattern of the classification is considered important to assess the venous drainage dominance and helpful to deduce existent and/or potential collateral pathway These findings may be useful for diagnostic and operative procedure

Effects of the pulmonary ligament on helical CT appearances of lower thoracic disease: anatomic-radiologic study / 中华放射学杂志

Objective To determine how the pulmonary ligament affects the helical CT appearances of the lower thoracic disease on the basis of the anatomic findings. Methods Four cadavers were cut transversely, with the section thickness of 11.3-13.4 mm. 57 patients with the lower thoracic disease were scanned using Somatom Plus 4, with administration of intravenous contrast material. The correlation of the anatomic findings of the pulmonary ligament and the helical CT appearances of the lower thoracic disease was evaluated. Results On cadaver sections, the right pulmonary ligament attached the lower lobe of the right lung to the esophagus, while the left ligament attached the lower lobe of the left lung to the esophagus or the descending aorta. In 40 pleural effusion and 7 pneumothorax cases, the pulmonary ligament tethered the medial aspect of the collapsed lower lobe and limited the shift of the lower lobe. In 40 pleural effusions, the ligament divided the medial pleural space into an anterior and a posterior compartment. The ligament showed thickness due to the invasion of the lesions of lower lobe including 7 tumors and 3 inflammatory diseases. Conclusion The pulmonary ligament can affect the helical CT appearances of the lower thoracic disease, such as lobe collapse, pleural effusion and pneumothorax; while the intraparenchymal and mediastinal abnormality can extend into the pulmonary ligament.

MR imaging study of the posterolateral structures of the normal knee / 中华放射学杂志

Objective To provide a practicable method for the complete display and localization of the posterolateral structures (PLS) of the normal knee through MRI study. Methods 30 tibial bone specimens were observed to establish the bony landmark for localizing the knee. In 50 cadaver knees, the angles between lateral tibial plateau and the long axis of the individual structure of PLS were measured. Then the scan methods of the oblique MR images were determined based on above results. The routine and oblique scans of T 1WI were performed in 40 normal knees. The display effect and appearance of the PLS were observed on MRI. Results The lateral tibial plateau was a stable bony landmark for measuring and localizing of the knee. In the 40 normal knees, The fibular collateral ligament could be intactly displayed on 70? posterior coronal oblique images in 34 cases (85%). The popliteus could be better seen on either 45? medial sagittal oblique in 34 cases (85%) or 60? posterior coronal oblique planes in 36 cases (90%). The popliteofibular ligament could be intactly appreciated on both 60? posterior coronal oblique in 32 cases (80%) and 70? lateral sagittal oblique images in 34 cases (85%). Although the arcuate ligament and the fabellofibular ligament could occasionally be seen on routine and oblique images, but the display rate was lower. Conclusion The oblique MR imaging can intactly display the main structures of PLS, and can be useful in diagnosing the injuries in those structures.