RESUMEN
OBJECTIVE: The cerebral and spinal venous systems have similar functions but unique anatomical and physiological properties. CSF occupies space in the cranial and spinal vaults, is continuously produced, and has many roles, including maintaining a favorable environment for CNS structures. The influence of the cerebrospinal venous system on CSF dynamics has been theorized since the 1940s. Newer studies suggest venous outflow pattern alterations in response to changes in body position. However, the relationship of postural cerebrospinal venous outflow shifts with and their influence on CSF homeostasis is not well understood. METHODS: The authors searched the published literature related to the anatomy and function of vertebral venous plexus (VVP), CSF, and positional cerebral venous flow characteristics. A comprehensive collection of literature was compiled and reviewed, and the relationship between cerebrospinal and venous system changes and alterations in body positions, with an emphasis on the craniocervical system, is discussed. RESULTS: The VVP is a network of valveless veins extending from the sacrum to the cranium that are interconnected with the cranial dural sinuses. The internal VVP occupies space within the extradural spinal canal and functions to return spinal venous blood to the heart, but it has additional properties, including the capability of bidirectional venous flow, an intraspinal dilatory capacity, and a role in cerebral venous outflow. When one rises to the upright position, CSF shifts toward the spinal canal and force vectors change, leading to reduced intracranial CSF pressure; simultaneously, cerebral venous outflow shifts from the jugular vein to the VVP outflow pathway. The venous outflow shift mechanism and its purpose are poorly understood. The authors review the known physiology of the system, identify gaps in knowledge to direct future research, and propose an interpretation of these data, concluding that position-dependent CSF and cerebrospinal venous shifts are part of a complementary positional craniospinal pressure regulation system that must be kept in balance for optimal CNS function. CONCLUSIONS: Current knowledge of the cerebrospinal venous anatomy, dynamic flow characteristics in response to gravity, and the venous system's influence on CSF suggests that the VVP plays a role in influencing CSF pressure, and the authors hypothesize that it plays a role in supporting intracranial pressure in the upright body posture. Further research is needed to better characterize the functional relationship of the VVP to CSF dynamics as well as identify potentially related disease states.
RESUMEN
Spinal cord injury is difficult to detect directly on postmortem computed tomography (PMCT) and it is usually diagnosed by indirect findings such as a hematoma in the spinal canal. However, we have encountered cases where the hematoma-like high-attenuation area in the cervical spinal canal was visible on PMCT, while no hematoma was observed at autopsy; we called it a "pseudo hematoma in the cervical spinal canal (pseudo-HCSC)." In this retrospective study, we performed statistical analysis to distinguish true from pseudo-HCSC. The cervical spinal canal was dissected in 35 autopsy cases with a hematoma-like high-attenuation area (CT values 60-100 Hounsfield Unit (HU)) in the spinal canal from the first to the fourth cervical vertebrae in axial slices of PMCT images. Of these 22 had a hematoma and 13 did not (pseudo-HCSC). The location and length of the hematoma-like high-attenuation and spinal cord areas were assessed on reconstructed PMCT images, true HCSC cases had longer the posterior hematoma-like area and shorter the spinal cord area in the midline of the spinal canal (P < 0.05). Furthermore, we found that true HCSC cases were more likely to have fractures and gases on PMCT while pseudo-HCSC cases were more likely to have significant facial congestion (P < 0.05). We suggest that pseudo-HCSC on PMCT is related to congestion of the internal vertebral venous plexus. This study raises awareness about the importance of distinguishing true HCSC from pseudo-HCSC in PMCT diagnosis, and it also presents methods for differentiation between these two groups.
Asunto(s)
Hematoma , Imágenes Post Mortem , Humanos , Estudios Retrospectivos , Hematoma/diagnóstico por imagen , Cuello , Canal Medular/diagnóstico por imagenRESUMEN
Atlas and axis instrumentation may be necessary in cases of several craniocervical junction pathologies. According to the Harms technique, C1-C2 polyaxial screws are inserted respectively in the C1 lateral masses and in C2 pedicles. C1 lateral mass screw insertion requires the careful subperiosteal dissection of the posterior elements of C1, the identification of the screw entry point by the downward distraction of C2 nerve root, and the cautious sparing of the overlying posterior external vertebral venous plexus (peVVP), whose bleeding, obstructing the surgical field, is sometimes barely controlled by hemostatic agents and swabbing. The authors describe in detail the anatomical aspects of an alternative surgical technique developed for the microsurgical transposition of the C1-C2 interposed external vertebral venous plexus in the case of Harms C1-C2 screw stabilization. The longitudinal median incision of the atlantoaxial membrane, followed by bilateral subperiosteal dissection and microsurgical section respectively at the inferior borders of the C1 laminae and at the superior borders of the C2 laminae, allows, as a "window opening," the symmetrical mediolateral transposition of the peVVP. This procedure provides a faster and cleaner anatomical exposition of the posterior surface of the C1 lateral mass and the C2 isthmus, preventing troublesome intraoperative venous bleeding that hinders C1 lateral mass screw insertion.
Asunto(s)
Tornillos Óseos , DisecciónRESUMEN
BACKGROUND AND AIMS: Both anaesthesiologists and spine surgeons consider the intra-abdominal pressure (IAP) as an important peri-operative factor affected by patient positioning. We assessed the change in IAP caused by using a thoraco pelvic support (inflatable prone support, IPS) with the subject under general anesthesia. The IAP was measured before, during and immediately after surgery. METHODS: The Spine Intra-Abdominal Pressure study (SIAP trial) is a prospective, single-arm, monocenter, observational study looking at changes in IAP prior, during and after spine surgery. The objective is to assess the change in IAP, measured via an indwelling urinary catheter, using the inflatable prone support (IPS) device during prone positioning of patients in spinal surgery. RESULTS: Forty (40) subjects requiring elective lumbar spine surgery in prone position were enrolled after providing informed consent. The inflation of the IPS results in a significant decrease of IAP (from a median of 9.2 mmHg to 6.46 mmHg (p < 0.001)) in patients undergoing spine surgery in prone position. This decrease in IAP was maintained throughout the procedure despite the discontinuation of muscle relaxants. No serious adverse events or unexpected adverse events occurred. CONCLUSION: The use of the thoraco-pelvic support IPS device was able to significantly lower the IAP during spine surgery.
Asunto(s)
Posicionamiento del Paciente , Columna Vertebral , Humanos , Estudios Prospectivos , Presión , Columna Vertebral/cirugía , Posicionamiento del Paciente/métodos , PelvisRESUMEN
El objetivo de la presente monografía, fue actualizar la anatomía del Plexo Venoso Vertebral (PVV) del perro de relevancia clínico-quirúrgica y asimismo evaluar el cumplimiento de la Nómina Anatómica Veterinaria (NAV). Se realizaron búsquedas electrónicas utilizando 9 bases de datos, donde se revisaron un total de 49 fuentes bibliográficas. De éstas, 20 correspondieron a artículos científicos. El criterio de exclusión fue el de publicaciones con más de 10 años de antigüedad, con excepción de libros de anatomía veterinaria de referencia base. Publicaciones que no estuvieran escritas en inglés, español o portugués, fueron también excluidas. En general, en la literatura revisada, existió consenso de cuáles son los componentes del PVV, junto con una escueta descripción de éste. El componente del PVV que es más ampliamente descrito y con mayor dimensión es el Plexo Vertebral Interno Ventral (PVIV). La función de retorno venoso sanguíneo alternativo hacia el corazón es la más nombrada. La no existencia de válvulas en el PVIV, pudiese ser una condición promotora para la metástasis tumoral a través del PVV. A nivel quirúrgico, la hemorragia del PVV, representa un peligro no despreciable para la vida del paciente. Con respecto a lo revisado y discutido, se puede concluir que: i) a pesar de la escasa descripción anatómica del PVV se pudo comprender cómo éste está compuesto ii) el nivel de evidencia que avala las distintas capacidades funcionales del PVV es bajo, no obstante, la información de la presentación de la hemorragia del PVV en las distintas cirugías es mayor iii) las variadas referencias bibliográficas consultadas no respetaron la NAV actual para describir al PVV.
SUMMARY: This monograph aims to provide an update on the anatomy of the Vertebral Venous Plexus (VVP) of the dog with emphasis on its clinical and surgical relevance and to evaluate compliance of terms in the literature with Nomina Anatomica Veterinaria (NAV). Electronic searches were conducted using 9 databases, where a total of 49 bibliographic sources were reviewed. Of these, 20 consisted of scientific articles. Publications with more than 10 years old were excluded from review, except for basic reference veterinary anatomy books. Publications that were not written in English, Spanish or Portuguese were also excluded. In general, in the literature reviewed, there was consensus on what the components of the VVP are, along with a brief description of VVP. The most widely described component of the VVP is the Ven- tral Internal Vertebral Plexus (VIVP). The function of alternative venous blood return to the heart is the most frequently described. The absence of valves in the VIVP could be a promoting condition for tumor metastasis through the VVP. At the surgical level, VVP hemorrhage represents a non-negligible threat to the patient's survival. With respect to what has been reviewed and discussed, it can be concluded that: i) despite the scarce anatomical description of the VVP, it was possible to understand how it is composed ii) the level of evidence that supports the different functional capacities of the VVP is low, however, the information on the ocurrence of VVP hemorrhage in surgical procedures is greater and iii) the various bibliographical references describing the VVP did not comply with the current NAV.
Asunto(s)
Animales , Columna Vertebral/irrigación sanguínea , Venas/anatomía & histología , Perros/anatomía & histologíaRESUMEN
Background: Bilateral transverse sinus stenosis (BTSS) is associated with intracranial hypertension. Enlarged vertebral venous plexus (EVVP) refers to a compensation mechanism against elevated intracranial pressure (ICP) in patients with BTSS. This study aims to investigate the influencing factors of EVVP. Methods: Patients with BTSS were prospectively recruited from the neurology department and neurosurgery department of Xuanwu Hospital Capital Medical University from January 2020 to December 2021. Results: A total of 37 patients were enrolled with a mean age of 45.42 ± 15.64 years. Women tend to be more susceptible to BTSS. The most common co-morbid disease was hypertension. The most common clinical manifestations were visual disorders, headaches, and tinnitus. BMI and DBP were significantly higher in BTSS patients without EVVP than those with EVVP. Multivariate analysis revealed that diastolic blood pressure (DBP) was negatively correlated with EVVP. In addition, a positive correlation between DBP and the ICP was also observed. A DBP of 81.5 mmHg was calculated as the cutoff value for the presence of EVVP. BTSS patients with DBP ≤ 81.5 mmHg had a higher incidence of EVVP and a lower ICP compared to those with DBP > 81.5 mmHg. Conclusions: DBP was identified as an independent predictor of EVVP. DBP was lower (≤81.5 mmHg) in patients with EVVP and therefore was associated with a lower ICP in patients with BTSS.
RESUMEN
BACKGROUND: Enlarged vertebral venous plexus (EVVP) was often observed in patients with bilateral transverse sinus stenosis (BTSS). The purpose of this study was to investigate the physiological role of EVVP in BTSS patients. METHODS: Forty-five BTSS patients and 92 normal controls were prospectively recruited from January 2014 to December 2019. The index of transverse sinus stenosis (ITSS) was used for the assessment of BTSS severity. Subjects underwent a standard lumbar puncture to measure the intracranial pressure (ICP). Papilledema and tinnitus were evaluated by using Frisén's grade and questionnaires for Tinnitus Handicap Inventory (THI), respectively. The intensity and impact of headache were assessed by using 10-point Numeric Pain Rating Scale and six-item Headache Impact Test, respectively. RESULTS: The BTSS group had more subjects with intracranial hypertension (IH) and less subjects with normal ICP than normal controls (p < 0.01; p < 0.01). BTSS patients had higher ICP than normal controls (p < 0.01). ICP was significantly lower in BTSS patients with EVVP than in those without EVVP (p < 0.01). No significant difference in ICP was found between normal controls with EVVP and those without EVVP (p = 0.99). A similar incidence of EVVP in BTSS patients and normal controls was found (p = 0.86). BTSS patients with IH exhibited a lower incidence of EVVP than those with normal ICP and overlapping ICP (p < 0.01; p < 0.01). The incidence of EVVP was not correlated with ITSS (p = 0.81). EVVP, rather than ITSS, correlated with ICP (p = 0.01). Furthermore, EVVP alleviated papilledema evaluated by Frisén's grade and tinnitus evaluated by the THI score in BTSS patients (p = 004; p = 0.02). CONCLUSIONS: EVVP in normal controls is a congenital phenomenon that exerts no impact on ICP. However, the presence of EVVP reduces ICP and alleviates IH-related papilledema and tinnitus in BTSS patients.
Asunto(s)
Hipertensión Intracraneal , Papiledema , Acúfeno , Constricción Patológica/complicaciones , Cefalea/etiología , Humanos , Hipertensión Intracraneal/diagnóstico , Hipertensión Intracraneal/etiología , Papiledema/diagnóstico , Papiledema/etiología , Acúfeno/diagnóstico , Acúfeno/etiología , Acúfeno/terapiaRESUMEN
The internal vertebral venous plexus (IVVP) is a thin-walled, valveless venous network that is located inside the vertebral canal, communicating with the cerebral venous sinuses. The objective of this study was to perform a morphometric analysis of the IVVP, dural sac, epidural space and vertebral canal between the L1 and L7 vertebrae with contrast-enhanced computed tomography (CT). Six clinically healthy adult dogs weighing between 12 kg to 28 kg were used in the study. The CT venographic protocol consisted of a manual injection of 880 mgI/kg of contrast agent (587 mgI/kg in a bolus and 293 mgI/mL by continuous infusion). In all CT images, the dimensions of the IVVP, dural sac, and vertebral canal were collected. Dorsal reconstruction CT images showed a continuous rhomboidal morphological pattern for the IVVP. The dural sac was observed as a rounded isodense structure throughout the vertebral canal. The average area of the IVVP ranged from 0.61 to 0.74 mm2 between L1 and L7 vertebrae (6.3-8.9% of the vertebral canal), and the area of the dural sac was between 1.22 and 7.42 mm2 (13.8-72.2% of the vertebral canal). The area of the epidural space between L1 and L7 ranged from 2.85 to 7.78 mm2 (27.8-86.2% of the vertebral canal). This CT venography protocol is a safe method that allows adequate visualization and morphometric evaluation of the IVVP and adjacent structures.
RESUMEN
The venous drainage of the vertebral and paravertebral regions is important for a better understanding of hematogenous disease spread. Moreover, the spine surgeon must be well acquainted with this anatomy to minimize intraoperative and postoperative complications. A comprehensive review of the vertebral venous plexus (Batson plexus) was performed with a concentration on the clinical and surgical correlations of this venous network.
Asunto(s)
Columna Vertebral/irrigación sanguínea , Venas/anatomía & histología , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Neuroanatomía/historiaRESUMEN
Fat-suppressed T1-weighted magnetic resonance images (MRIs) enhanced with gadolinium can evaluate the internal vertebral venous plexus and cauda equina. This study compared such findings with clinical situations and discusses whether these are helpful for symptomatic grading and selection at the surgical level in patients with lumbar central stenosis. A total of 263 patients (337 levels < 75 mm2 of dural cross sectional area (DCSA)) were included. The enhancement patterns of dorsal epidural vein (DVCE), periradicular vein (PVCE) and intraradicular vein (IRCE) were assessed qualitatively. The quantification of IRCE was acquired by the ratio (%) (enhancement parameters: MS/P1, MS/P2, WR/P1, WR/P2) of signal intensities between the cauda equina (MS-IRCE: maximal spot rootlet, WR-IRCE: whole rootlets) and psoas muscle (P1, P2). Receiver-operator characteristic curves were plotted to obtain imaginary cutoff values for the prediction of symptomatic appearance or operation decision. All levels were classified into seven groups on the basis of pain distribution and the presence of IRCE. PVCE was significantly related to high incidences of symptoms, unilaterality and operation. DVCE and IRCE were connected with high incidences of symptoms, bilaterality and operation. IRCE was also related to high visual analogue scale (VAS), small DCSA and high enhancement parameters. The order of the group was concordant with the degree of enhancement parameters (p = 0.000). Cutoff values of enhancement parameters for prediction were as follows: symptoms (147/123/140/121), bilaterality (165/139/157/137) and operation (164/139/159/138). Enhancement patterns and parameters could help in stratification, grading and decision-making at the surgical level.
RESUMEN
BACKGROUND: The most common sites of recurrence after liver transplantation for hepatocellular carcinoma (HCC) have been reported to be the liver, lung, bone, and adrenal glands, but there have also been many reports of cases of multiple recurrence. The prognosis after recurrence is poor, with reported median survival after recurrence of HCC ranging from 9 to 19 months. Here, we report a case of long-term survival after recurrence of pharyngeal metastasis following living-donor liver transplantation (LDLT) for HCC within the Milan criteria, by resection of the metastatic region and cervical lymph node dissection. CASE PRESENTATION: A 47-year-old man with a Model End-stage Liver Disease (MELD) score of 11 underwent LDLT for HCC within the Milan criteria for liver cirrhosis associated with hepatitis B virus infection, with his 48-year-old elder brother as the living donor. One year and 10 months after liver transplantation, he visited a nearby hospital with a chief complaint of discomfort on swallowing. A pedunculated polyp was found in the hypopharynx, and biopsy revealed HCC metastasis. We performed pharyngeal polypectomy. Two years later, cervical lymph node metastasis appeared, and neck lymph node dissection was performed. Although recurrence subsequently occurred three times in the grafted liver, the patient is still alive 12 years and 10 months after recurrence of pharyngeal metastasis. He is now a tumor-free outpatient taking sorafenib. CONCLUSION: It is necessary to recognize that the nasopharyngeal region is a potential site of HCC metastasis. Prognostic improvement can be expected with close follow-up, early detection, and multidisciplinary treatment, including radical resection.
Asunto(s)
Carcinoma Hepatocelular/terapia , Enfermedad Hepática en Estado Terminal/cirugía , Neoplasias Hepáticas/terapia , Trasplante de Hígado/efectos adversos , Recurrencia Local de Neoplasia/diagnóstico , Neoplasias Faríngeas/secundario , Aloinjertos/diagnóstico por imagen , Aloinjertos/patología , Aloinjertos/cirugía , Biopsia , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/secundario , Ablación por Catéter , Quimioterapia Adyuvante/métodos , Combinación de Medicamentos , Enfermedad Hepática en Estado Terminal/etiología , Hepatectomía , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Hígado/cirugía , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patología , Donadores Vivos , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/terapia , Ácido Oxónico/uso terapéutico , Neoplasias Faríngeas/diagnóstico , Neoplasias Faríngeas/terapia , Faringe/diagnóstico por imagen , Faringe/patología , Faringe/cirugía , Tomografía Computarizada por Tomografía de Emisión de Positrones , Sorafenib/uso terapéutico , Tegafur/uso terapéutico , Resultado del TratamientoRESUMEN
BACKGROUND: Vertebral arteriovenous fistulas (VAVFs) are uncommon high-flow communications between a vertebral artery and surrounding venous plexus that occur spontaneously or secondary to trauma. CASE DESCRIPTION: A woman aged 57 years presented with a multiday history of rapidly progressive numbness and weakness in the left C5-C6 dermomyotomes. Her physical examination findings and subsequent electrophysiological testing were suggestive of a brachial radiculoplexopathy. Noninvasive imaging demonstrated venous congestion with multilevel compromise of the left-sided cervical foramina, and subsequent vertebral angiography confirmed a VAVF, which was treated with trapping of the involved vertebral artery segment. Her numbness and weakness progressively improved with concurrent involution of the dilated veins. CONCLUSIONS: This is a rare case of VAVF manifesting as a brachial radiculoplexopathy. Although rare, VAVF may be considered as a potential cause in patients presenting with similar symptoms.
Asunto(s)
Fístula Arteriovenosa/patología , Arteria Vertebral/anomalías , Angiografía , Fístula Arteriovenosa/diagnóstico , Fístula Arteriovenosa/cirugía , Neuropatías del Plexo Braquial/diagnóstico , Diagnóstico Diferencial , Embolización Terapéutica/métodos , Femenino , Humanos , Persona de Mediana Edad , Radiculopatía/diagnósticoRESUMEN
BACKGROUND: Bone metastasis of cancer can be a result from systemic blood spreading or vertebral venous plexus spreading. Systemic blood pathway induced bone metastasis can happen in any bone in the body since the spreading is considered to be random. However, it remains unknown whether there is any pattern of vertebral venous plexus related bone metastasis. In this study, we explored bone metastasis patterns in patients whose primary tumors had been well identified. METHODS: We included 290 consecutive cancer patients with bone metastases but no visceral metastases, out of 2559 patients whose bone metastases were diagnosed by positron emission tomography/computed tomography, between Jan 2015 and Oct 2017 at the Fudan University Shanghai Cancer Center. We excluded those with visceral metastasis to ensure that our study focused on metastasis through the vertebral venous plexus. And we analyzed the distribution and pattern of skeletal metastases. RESULTS: Of the 290 patients, 28 had head and neck tumors, 178 had thorax tumors, 49 had abdominal tumors and 35 had pelvic tumors; 102 (35%) had only one bone containing a metastasis and 188 (65%) had multiple bones containing metastases. Overall, metastases to the thoracic skeleton were more common in patients with thorax tumors than in other patients (81% vs. 67%, Pâ¯=â¯0.007); metastases to the cervical spine or thoracic bones were more common in patients with primary tumors above the diaphragm than those below the diaphragm (82% vs. 66%, Pâ¯=â¯0.002). Among those with only one bone containing a metastasis (nâ¯=â¯102), patients with head and neck tumors had a higher incidence of cervical spine metastasis than other patients (25% vs. 2%, Pâ¯=â¯0.03), those with thorax tumors had a higher incidence of thoracic bone metastasis than other patients (56% vs. 35%, Pâ¯=â¯0.035), and those with pelvic tumors had a higher incidence of pelvis bone metastasis than other patients (78% vs. 27%, Pâ¯=â¯0.000054). CONCLUSIONS: In patients with only one bone containing a metastasis but no visceral metastasis, bones near the primary were more likely to be first metastasized. This may be a valuable clue to primary tumor sites in patients with cancers of unknown primaries.
RESUMEN
The vertebral venous plexus is a vascular network that runs from the cervical to sacral vertebral canal in the spine of mammals. The objective of this study was to perform an anatomical study of the internal vertebral venous plexus (IVVP) in horses. The spine of five horse specimens (four adults and one foal) was dissected for morphological analysis of the IVVP. The IVVP was observed in the ventral epidural space of the vertebral canal and was composed by two symmetrical longitudinal veins. There was a difference in the IVVP diameter and morphology between foal and adult horses. In all the specimens, the IVVP was more developed at cervical segments, while a decrease in the IVVP diameter was seen in sacral and caudal segments. The cervical IVVP communicated cranially with the basilar, interbasilar and sigmoid sinuses. Transverse communicating branches between left and right IVVP were occasionally observed at the cervical, sacral and caudal vertebral segments. In conclusion, the IVVP in horses is similar to other domestic animals, has transverse connections and is more developed at cervical segment. The diameter of the longitudinal veins decreased and at the caudal segment reaches its thinnest development.
A lo largo de la columna vertebral de los mamíferos se extiende una red de vasos venosos conocida como plexo venoso vertebral interno (PVVI). Se realizó un estudio anatómico del PVVI en equinos mediante disección anatómica, donde se expuso el PVVI de 5 especímenes equinos (4 adultos y un potrillo) para estudio morfologico y registro fotográfico. El PVVI se observó en todo el espacio epidural espinal, conformado por dos venas longitudinales que recorrían el canal vertebral dispuestas de manera romboidal. Se observaron diferencias en el diámetro y morfología del PVVI de adultos en relación a lo observado en potrillos. El PVVI de equinos presentó su mayor desarrollo en el segmento vertebral cervical, disminuyendo el diámetro hacia caudal hasta desaparecer en la zona sacral o caudal. Se apreciaron ramas venosas transversales comunicando las venas longitudinales, destacando los senos venosos presentes en la zona cervical y las ramas transversas comunicantes en los segmentos cervical, sacral y caudal. En conclusión, el PVVI en equinos presentó un mayor desarrollo en la zona cervical y desde la zona torácica hacia caudal el PVVI disminuyó su desarrollo, siendo la zona caudal la más delgada.
Asunto(s)
Animales , Columna Vertebral/irrigación sanguínea , Venas/anatomía & histología , Caballos/anatomía & histología , TóraxRESUMEN
BACKGROUND: Spontaneous spinal epidural hematoma (SSEH) is a rare neurosurgical emergency. It presents as acute spinal cord compression and usually requires surgical decompression. The patients who will benefit most from decompression surgery are unknown, and the factors associated with prognosis remain controversial. The purpose of our study was to identify the clinical features, treatments, and main factors related to the prognosis of SSEH. METHODS: We reviewed the records of 24 patients treated for SSEH from September 2010 to January 2016 at West China Hospital. Clinical features, radiologic images, treatment methods, and clinical outcomes were reviewed retrospectively. To ascertain which factors were related to outcomes, statistical analysis was performed. RESULTS: Among 24 patients, 19 presented with severe initial neurologic deficits (American Spinal Injury Association grade A-C) underwent decompressive surgery, and the remaining patients (initial American Spinal Injury Association grade D or E) received conservative treatment. Among the 19 patients in the operation group, seven (36.8%) had good outcomes, whereas 12 (63.2%) had poor outcomes. All patients in the conservative group had good outcomes. CONCLUSIONS: SSEH is a rare but serious illness. It is more likely that SSEH arises from a ruptured internal vertebral venous plexus. The initial neurologic status is the determining factor influencing the treatment method and clinical outcome. The number of involved segments cannot be used to decide the treatment method or predict prognosis. Patients with shorter operative intervals appear to have better neurologic recovery.
Asunto(s)
Descompresión Quirúrgica/métodos , Hematoma Espinal Epidural/diagnóstico , Hematoma Espinal Epidural/cirugía , Resultado del Tratamiento , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Examen Neurológico , Estudios Retrospectivos , Médula Espinal/diagnóstico por imagenRESUMEN
OBJECTIVES: This study focuses on the adjacent venous structures of tumors and their treatment in patients with second cervical (C2) dumbbell-shaped peripheral nerve sheath tumors (PNSTs). PATIENTS AND METHODS: The authors retrospectively analyzed the clinical outcome and the venous structures involved with tumors in 16 patients with C2 dumbbell-shaped PNSTs treated surgically between 2008 and 2015. RESULTS: The venous structures at the craniocervical junction could be visualized in all 16 patients on contrast-enhanced T1-weighted magnetic resonance imaging. The venous structures could be identified during surgery. The common locations of venous structures were noted as follows: the suboccipital cavernous sinus was located anterolateral and toward the top of the tumor; the vertebral venous plexus was located ventral to the tumor; and the vertebral artery venous plexus was shifted anteriorly and laterally by the tumor. Total excision was achieved in all 16 patients. Clinical improvements were observed in all 16 patients postoperatively. CONCLUSIONS: The C2 dumbbell-shaped PNSTs were closely related to the suboccipital venous structures. Understanding and proper management of these venous structures is critical for reduced bleeding and successful surgery.
Asunto(s)
Cuello/irrigación sanguínea , Neoplasias de la Vaina del Nervio/cirugía , Procedimientos Neuroquirúrgicos/métodos , Venas/diagnóstico por imagen , Adulto , Anciano , Vértebra Cervical Axis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuello/diagnóstico por imagen , Neoplasias de la Vaina del Nervio/diagnóstico por imagen , Procedimientos Neuroquirúrgicos/normas , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
How blood was able to reach the heads of the long-necked sauropod dinosaurs has long been a matter of debate and several hypotheses have been presented. For example, it has been proposed that sauropods had exceptionally large hearts, multiple 'normal' sized hearts spaced at regular intervals up the neck or held their necks horizontal, or that the siphon effect was in operation. By means of an experimental model, we demonstrate that the siphon principle is able to explain how blood was able to adequately perfuse the sauropod brain. The return venous circulation may have been protected from complete collapse by a structure akin to the vertebral venous plexus. We derive an equation relating neck height and mean arterial pressure, which indicates that with a mean arterial pressure similar to that of the giraffe, the maximum safe vertical distance between heart and head would have been about 12â m. A hypothesis is presented that the maximum neck length in the fossil record is due to the siphon height limit. The equation indicates that to migrate over high ground, sauropods would have had to either significantly increase their mean arterial pressure or keep their necks below a certain height dependent on altitude.
Asunto(s)
Presión Arterial/fisiología , Dinosaurios/anatomía & histología , Dinosaurios/fisiología , Cuello/anatomía & histología , Altitud , Animales , Circulación Sanguínea , Diálisis , Modelos Biológicos , Presión , AguaRESUMEN
PURPOSE: This study focuses on the following questions: What are the morphological features at the transdural course of radiculomedullary veins? How are these short transdural segments that may harbour pathological arteriovenous shunts connected to the internal vertebral venous plexus? Is the conception of a reflux-impeding mechanism at the transdural segment indispensable and convincing? METHODS: A total of 102 radiculospinal veins were studied microscopically at various levels of the spinal canal using serial paraffin and semi-thin sections. In addition, 26 vessels were investigated microangiographically following orthograde (12) or attempted retrograde (14) opacification of the intradural venous segment with barium sulphate. After paraplast-embedding, contact-microradiographs were taken using high-resolution spectroscopic plates. RESULTS: At their transdural course, the veins showed narrowing of their lumen accompanied by changes in the vessel wall composition and a tortuous course. Two structurally distinct arrangements of the transdural segment could be identified: A slit type was seen in 60% of the veins studied and a bulge- or nodular type was seen in 35% of the veins. In total, 5% of cases could not be assigned to either one of these types. Reflux to radicular veins from the outside of the dura mater could be produced in 2 out of 14 specimens. The extradural venous plexus, which primarily receives the radicular vein, was composed more frequently of lacunar spaces rather than plexiform blood vessel convolutions. Rare observations were fibrotic, blind ending radiculomedullary veins and continuation of a distinct venous blood vessel after crossing the dura. CONCLUSIONS: Reflux from the epidural plexus to radicular veins is not reliably stopped at the dural level and possibly physiological. Different arrangements of the transdural course of the veins appear to be at least appropriate to modulate flow. The purpose for two different types of radicular vein exit is unclear. The clinical impact of disturbed reflux-control is uncertain, which is in stark contrast to the severe consequences resulting from dural arteriovenous shunts. The functional role of the probably predominant epidural venous plexus for the spinal cord blood circulation remains poorly understood.
Asunto(s)
Duramadre/citología , Duramadre/diagnóstico por imagen , Flebografía/métodos , Médula Espinal/irrigación sanguínea , Venas/citología , Humanos , Médula Espinal/citología , Médula Espinal/diagnóstico por imagenRESUMEN
INTRODUCTION: Sinonasal cancer is an uncommon neoplasm, often associated with exposure to occupational hazards and delayed diagnosis. CASE REPORT: The authors report a rare case of solitary liver metastasis from ethmoid sinus adenocarcinoma treated by surgical resection. No clinical or radiological sign of recurrence was observed with a follow-up of 3 months. DISCUSSION: Adenocarcinoma of the ethmoid sinus is characterized by its aggressiveness and its tendency to recurrence. Metastases are rare and can be found in unexpected organs due to dissemination via collateral venous plexuses. The role of chemotherapy has not been clearly established. Due to their rarity, the treatment of metastases has not yet been defined.
Asunto(s)
Adenocarcinoma/secundario , Senos Etmoidales , Neoplasias Hepáticas/secundario , Neoplasias de los Senos Paranasales/patología , Adenocarcinoma/cirugía , Senos Etmoidales/patología , Senos Etmoidales/cirugía , Hepatectomía/métodos , Humanos , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias de los Senos Paranasales/cirugía , Pronóstico , Resultado del TratamientoRESUMEN
Dural arteriovenous fistulas (DAVFs) of the hypoglossal canal (HCDAVFs) are rare and display a complex angiographic anatomy. Hitherto, they have been referred to as various entities (for example, "marginal sinus DAVFs") solely described in case reports or small series. In this in-depth review of HCDAVF, the authors describe clinical and imaging findings, as well as treatment strategies and subsequent outcomes, based on a systematic literature review supplemented by their own cases (120 cases total). Further, the involved craniocervical venous anatomy with variable venous anastomoses is summarized. Hypoglossal canal DAVFs consist of a fistulous pouch involving the anterior condylar confluence and/or anterior condylar vein with a variable intraosseous component. Three major types of venous drainage are associated with distinct clinical patterns: Type 1, with anterograde drainage (62.5%), mostly presents with pulsatile tinnitus; Type 2, with retrograde drainage to the cavernous sinus and/or orbital veins (23.3%), is associated with ocular symptoms and may mimic cavernous sinus DAVF; and Type 3, with cortical and/or perimedullary drainage (14.2%), presents with either hemorrhage or cervical myelopathy. For Types 1 and 2 HCDAVF, transvenous embolization demonstrates high safety and efficacy (2.9% morbidity, 92.7% total occlusion). Understanding the complex venous anatomy is crucial for planning alternative approaches if standard transjugular access is impossible. Transarterial embolization or surgical disconnection (morbidity 13.3%-16.7%) should be reserved for Type 3 HCDAVFs or lesions with poor venous access. A conservative strategy could be appropriate in Type 1 HCDAVF for which spontaneous regression (5.8%) may be observed.