Different anatomic patterns of the indirect tendon of the rectus femoris.

PURPOSE: The rectus femoris forms the anterior portion of the quadriceps muscle. It has a proximal tendinous complex, which is constituted by a direct tendon, an indirect tendon, and a variable third tendon. Direct and indirect tendons converge into a common tendon. The purposes of this study are to add anatomical knowledge about the proximal tendinous complex and describe anatomical variants of the indirect tendon and, on these basis, categorize different anatomical patterns. METHOD: In this study, 48 hemipelvis from bodies donated to the Universitat Autònoma de Barcelona have been dissected to examine the proximal tendinous complex of the rectus femoris. RESULTS: The following anatomical variants of the indirect tendon were described: inferior aponeurotic expansion in 23/48 cases (47.9%); superior aponeurotic expansion in 21/48 cases (43.7%); and an unusual origin of the myotendinous junction of the rectus femoris in the free portion of the indirect tendon in 19/48 cases (39.6%). On the basis of the aponeurotic expansions, the following anatomical patterns of the indirect tendon were defined: standard (19/48 cases, 39.6%), superior and inferior complex (15/48 cases, 31.2%), inferior complex (8/48 cases, 16.7%), and superior complex (6/48 cases, 12.5%). CONCLUSION: We can categorize four different anatomical patterns of the indirect tendon, three of which are complex. We suggest that complex patterns can cause an increased stiffness of the indirect tendon and so be considered non-modifiable risk factors for rectus femoris injuries. Finally, it would be useful to identify complex patterns and perform injury prevention actions through specific physical preparation programs.

A newly discovered membrane at the origin of the proximal tendinous complex of the rectus femoris.

PURPOSE: The rectus femoris (RF) forms the anterior portion of the quadriceps muscle group. It has a proximal tendinous complex (PTC) which is constituted by a direct tendon (DT), an indirect tendon (IT), and a variable third head. Direct and indirect tendons finally converge into a common tendon (CT). All the PTC shows a medially sloping in its proximal insertion.We investigated several anatomical specimens and discovered a new component: a membrane connecting the CT with the anterior superior iliac spine. Such membrane constitutes a new origin of the PTC. The aim of this study was to clarify whether this membrane was an anatomical variation of the PTC or a constant structure and to describe its morphology and trajectory. MATERIAL AND METHODS: We dissected 42 cadaveric lower limbs and examined the architecture of the PTC. We paid special attention to the morphology and interaction patterns between the tendons and the membrane. RESULTS: We demonstrated that the membrane is a constant component of the PTC. It has a lateral to medial trajectory and is in relation to the common tendon, the DT, and IT, which present a medial slope. This suggests that the membrane has an stabilizer role for the PTC, acting as a corrector of the inclined vector of the complex. CONCLUSION: The RF injuries are frequent in football. The newly discovered membrane is a constant component of the PTC and its integrity should be included in the algorithm to diagnose injuries.

Surface anatomical landmarks for the location of posterior sacral foramina in sacral nerve stimulation.

BACKGROUND: Sacral nerve stimulation is a common treatment for various pelvic floor disorders. It consists of the percutaneous introduction of electrodes through the posterior sacral foramina for therapeutic stimulation of the target sacral spinal nerve. The aim of our study was to determine the surface anatomical landmarks of the sacrum to facilitate identification of the posterior sacral foramina. METHODS: This study was conducted on 20 human cadavers. The cadavers were placed in a prone position, and all the soft tissues of the sacral region were removed to allow exposure of the osseous structures. Different measurements were taken in relation to the posterior sacral foramina, the posterior superior iliac spine (PSIS) and the median sacral crest (MSC). A median coefficient of variation (CV) was determined. RESULTS: The diameter of the second sacral foramen showed the greatest variability. The distances between each individual foramen and the MSC had an acceptable variability (CV < 20%). In contrast, the distance between foramina had a high variability. The distance between PSIS and the second posterior sacral foramen was also found to have an acceptable variability (CV < 20%). However, the angle formed by an horizontal line between PSIS and a line between PSIS and S2 foramina had high variability. CONCLUSIONS: We found that the distance between sacral foramina and MSC is relatively constant while the distance between foramina and the relations between foramina and PSIS is highly variable. Detailed knowledge of the anatomy may facilitate electrode placement and is complementary to the regular use of fluoroscopy.

Imaging of cellular aging in human retinal blood vessels.

To date two main aging vascular lesions have been reported in elderly human retinas: acellular capillaries and microaneurysms. However, their exact mechanism of formation remains unclear. Using high resolution microscopy techniques we revise cellular alterations observed in aged human retinal vessels, such as lipofuscin accumulation, caveolae malfunction, blood basement membrane disruption and enhanced apoptosis that could trigger the development of these aging vascular lesions. Moreover, we have generated a set of original images comparing retinal vasculature between middle and old aged healthy humans to show in a comprehensive manner the main structural and ultrastructural alterations occurred during age in retinal blood vessels.

Comparison of three different minimally invasive intramedullary screw for proximal phalanx fractures. A biomechanical study. / Comparación de tres técnicas de tornillo endomedular mínimamente invasivo para fracturas de falange proximal. Estudio biomecánico.

BACKGROUND AND OBJECTIVE: Phalangeal fractures are the most common hand fractures. In the last years, intramedullary compression screw (IMHCS) for instable transverse or short oblique proximal P1 fractures have been described. Although both anterograde (intraarticular or trans-articular) and retrograde IMHCS techniques have shown good results, no comparison between anterograde and retrograde screw in P1 fractures has been published. We sought to determine stability with retrograde IMHCS and anterograde IMHCS, both trans-articular and intra-articular technique, in a cadaveric transverse proximal P1 fracture model, at two different levels. MATERIAL AND METHODS: We performed a biomechanical study in 30 fresh-frozen human cadaveric P1 fracture model. Fracture was performed at 9-mm from the metacarpo-phalangeal (MCP) joint in 15 specimens, whereas it was done at 15 mm in the other 15. In turn, in each group, five fractures were stabilized with an anterograde intra-articular IMHCS, five with anterograde trans-articular IMHCS and other five with retrograde IMHCS. RESULTS: Anterograde IMHCS fixation in 9-mm P1 fractures (both trans- and intra-articular technique, 62.74 N and 70.86 N, respectively) was found to be more stable than retrograde IMHCS one (32.72 N) (p = 0.022). Otherwise, retrograde IMHCS fixation was found to be more stable in more distal P1 fractures (90.52 N retrograde vs. 57.64 N trans-articular vs. 42.92 N intra-articular; p = 0.20). CONCLUSIONS: Anterograde IMHCS fixation in proximal transverse P1 bone cut in a cadaveric model provides more stability than retrograde IMHCS, while retrograde screw provides more stability when the bone cut is located more distal.

[Translated article] Comparison of three different minimally invasive intramedullary screw for proximal phalanx fractures. A biomechanical study.

BACKGROUND AND OBJECTIVE: Phalangeal fractures are the most common hand fractures. In the last years, intramedullary compression screw (IMHCS) for instable transverse or short oblique proximal P1 fractures have been described. Although both anterograde (intraarticular or trans-articular) and retrograde IMHCS techniques have shown good results, no comparison between anterograde and retrograde screw in P1 fractures has been published. We sought to determine stability with retrograde IMHCS and anterograde IMHCS, both trans-articular and intra-articular technique, in a cadaveric transverse proximal P1 fracture model, at two different levels. MATERIAL AND METHODS: We performed a biomechanical study in 30 fresh-frozen human cadaveric P1 fracture model. Fracture was performed at 9-mm from the metacarpo-phalangeal (MCP) joint in 15 specimens, whereas it was done at 15mm in the other 15. In turn, in each group, five fractures were stabilised with an anterograde intra-articular IMHCS, five with anterograde trans-articular IMHCS and other five with retrograde IMHCS. RESULTS: Anterograde IMHCS fixation in 9-mm P1 fractures (both trans- and intra-articular technique, 62.74N and 70.86N, respectively) was found to be more stable than retrograde IMHCS one (32.72N) (p=0.022). Otherwise, retrograde IMHCS fixation was found to be more stable in more distal P1 fractures (90.52N retrograde vs. 57.64N trans-articular vs. 42.92N intra-articular; p=0.20). CONCLUSIONS: Anterograde IMHCS fixation in proximal transverse P1 bone cut in a cadaveric model provides more stability than retrograde IMHCS, while retrograde screw provides more stability when the bone cut is located more distal.

Role of imaging techniques in the diagnosis of selective hypertrophy of the tensor fascia lata.

The tensor fascia lata is a muscular structure that forms part of the lateral portion of the pelvis and proximal thigh. Because conditions affecting this muscle have not been widely reported and are relatively unknown, hypertrophy and pseudo-hypertrophy of the tensor fascia lata, although relatively common imaging findings, often go undiagnosed; instead, radiologists perform the differential diagnosis with more complex and more dangerous conditions. This article aims to review the anatomic and functional characteristics of the tensor fascia lata, going into detail about the radiological description of this muscle and pathological conditions that can affect it, as well as reviewing the relevant literature.

The role of the flexor carpi radialis muscle in scapholunate instability.

PURPOSE: The flexor carpi radialis (FCR) muscle has been suggested to act as a dynamic scaphoid stabilizer. Because the FCR tendon uses the scaphoid tuberosity as a pulley to reach its distal insertion onto the second metacarpal, it has been hypothesized that FCR muscle contraction generates a dorsally directed vector that resists the scaphoid from rotating into flexion. The purpose of the present study was to validate that hypothesis and clarify the role of the FCR as a dynamic scaphoid stabilizer. METHODS: Ten fresh cadaver wrist specimens were tested. A custom-designed testing apparatus was used to hold the forearm and wrist vertically, in neutral forearm rotation. A 6-degree-of-freedom, electromagnetic motion-tracking device, with sensors attached to the scaphoid, triquetrum, capitate, and radius, was used to monitor spatial changes in carpal alignment as a result of isometrically loading the FCR in 5 different wrist positions. RESULTS: In all specimens and all wrist positions, the scaphoid consistently rotated into flexion when the FCR was loaded. It also exhibited variable degrees of pronation or supination, depending on whether the wrist was in flexion or extension. When the wrist was loaded in neutral position, the scaphoid consistently supinated and the triquetrum pronated, these differences being statistically significant (p < .05). CONCLUSIONS: The scaphoid consistently rotated into flexion and supination when the FCR was loaded, while the triquetrum rotated in flexion and pronation. The positive effects of FCR muscle re-education in dynamic scapholunate instabilities can be explained not by this muscle's capability of extending the scaphoid, as has often been hypothesized, but by its ability to induce supination to the scaphoid and pronation to the triquetrum. Such opposite rotations are likely to result in a dorsal coaptation of the scapholunate joint with relaxation of the dorsal scapholunate ligament.

[Translated article] Comparison of three different minimally invasive intramedullary screw for proximal phalanx fractures. A biomechanical study / Comparación de tres técnicas de tornillo endomedular mínimamente invasivo para fracturas de falange proximal. Estudio biomecánico

Background and objective: Phalangeal fractures are the most common hand fractures. In the last years, intramedullary compression screw (IMHCS) for instable transverse or short oblique proximal P1 fractures have been described. Although both anterograde (intraarticular or trans-articular) and retrograde IMHCS techniques have shown good results, no comparison between anterograde and retrograde screw in P1 fractures has been published. We sought to determine stability with retrograde IMHCS and anterograde IMHCS, both trans-articular and intra-articular technique, in a cadaveric transverse proximal P1 fracture model, at two different levels. Material and methods: We performed a biomechanical study in 30 fresh-frozen human cadaveric P1 fracture model. Fracture was performed at 9-mm from the metacarpo-phalangeal (MCP) joint in 15 specimens, whereas it was done at 15 mm in the other 15. In turn, in each group, five fractures were stabilized with an anterograde intra-articular IMHCS, five with anterograde trans-articular IMHCS and other five with retrograde IMHCS. Results: Anterograde IMHCS fixation in 9-mm P1 fractures (both trans- and intra-articular technique, 62.74 N and 70.86 N, respectively) was found to be more stable than retrograde IMHCS one (32.72 N) (p = 0.022). Otherwise, retrograde IMHCS fixation was found to be more stable in more distal P1 fractures (90.52 N retrograde vs. 57.64 N trans-articular vs. 42.92 N intra-articular; p = 0.20). Conclusions: Anterograde IMHCS fixation in proximal transverse P1 bone cut in a cadaveric model provides more stability than retrograde IMHCS, while retrograde screw provides more stability when the bone cut is located more distal.(AU)

Antecedentes y objetivo: Las fracturas de falange proximal (FP) son las fracturas más frecuentes de la mano. En los últimos años, se ha descrito el uso de tornillos endomedulares sin cabeza (TESC) para las fracturas inestables transversas u oblicuas de la FP. A pesar de que tanto la técnica anterógrada como retrógrada con TESC han mostrado buenos resultados, no se ha publicado ningún estudio comparativo de su uso en fracturas de FP. Nuestro objetivo es determinar la estabilidad que se obtiene con el uso de TESC retrógrados y anterógrados en un modelo en cadáver de fractura transversa proximal de FP, a dos niveles diferentes. Material y métodos: Realizamos un estudio biomecánico en 30 modelos de fractura de FP de cadáver fresco-congelado. La osteotomía se realizó a los 9 mm desde la articulación metacarpofalángica (MCF) en 15 especímenes, y a una distancia de 15 mm en los otros 15. A su vez, en cada grupo, cinco osteotomías se estabilizaron con un TESC anterógrado intraarticular, cinco mediante un TESC anterógrado transarticular y cinco con un TESC retrógrado. Resultados: La fijación con TESC anterógrado en osteotomías realizadas a los 9 mm (tanto con la técnica transarticular como intraarticular, 62,74 N y 70,86 N, respectivamente) fue más estable que la fijación con TESC retrógrado (32,72 N) (p 0,022). Por otra parte, la fijación con TESC retrógrado fue más estable en el modelo de fractura más distal (90,52 N retrógrado vs. 57,64 N transarticular vs. 42,92 N intraarticular (p = 0,20). Conclusiones: La fijación con TESC retrógrado ofrece más estabilidad en fracturas más distales, mientras que las técnicas anterógradas son más estables en fracturas proximales.(AU)

Transfer of the musculocutaneous nerve branch to the brachialis muscle to the triceps for elbow extension: anatomical study and report of five cases.

We report the study of the anatomical feasibility of transferring the nerve to the brachialis muscle to the upper medial head motor branch that innervate the triceps, and outcomes of such transfers in restoring elbow extension in five patients with posterior cord lesion of the brachial plexus. The length of the branches to the brachialis muscle measured 7.6 cm and the triceps upper medial head motor branch was 5 cm in 10 adult cadavers. Five male patients were treated with this transfer 5 months after the injury (range 4 to 6 months) after posterior cord injury of the brachial plexus with a mean follow-up of 31 months (range 28 to 36 months). Elbow extension scored M4 in all cases. No complications occurred. These preliminary results suggest that transferring the nerve to the brachialis muscle is an effective technique for the reconstruction of elbow extension after posterior cord brachial plexus injuries. LEVEL OF EVIDENCE: IV.

How 3D patient-specific instruments improve accuracy of pelvic bone tumour resection in a cadaveric study.

OBJECTIVES: To assess the accuracy of patient-specific instruments (PSIs) versus standard manual technique and the precision of computer-assisted planning and PSI-guided osteotomies in pelvic tumour resection. METHODS: CT scans were obtained from five female cadaveric pelvises. Five osteotomies were designed using Mimics software: sacroiliac, biplanar supra-acetabular, two parallel iliopubic and ischial. For cases of the left hemipelvis, PSIs were designed to guide standard oscillating saw osteotomies and later manufactured using 3D printing. Osteotomies were performed using the standard manual technique in cases of the right hemipelvis. Post-resection CT scans were quantitatively analysed. Student's t-test and Mann-Whitney U test were used. RESULTS: Compared with the manual technique, PSI-guided osteotomies improved accuracy by a mean 9.6 mm (p < 0.008) in the sacroiliac osteotomies, 6.2 mm (p < 0.008) and 5.8 mm (p < 0.032) in the biplanar supra-acetabular, 3 mm (p < 0.016) in the ischial and 2.2 mm (p < 0.032) and 2.6 mm (p < 0.008) in the parallel iliopubic osteotomies, with a mean linear deviation of 4.9 mm (p < 0.001) for all osteotomies. Of the manual osteotomies, 53% (n = 16) had a linear deviation > 5 mm and 27% (n = 8) were > 10 mm. In the PSI cases, deviations were 10% (n = 3) and 0 % (n = 0), respectively. For angular deviation from pre-operative plans, we observed a mean improvement of 7.06° (p < 0.001) in pitch and 2.94° (p < 0.001) in roll, comparing PSI and the standard manual technique. CONCLUSION: In an experimental study, computer-assisted planning and PSIs improved accuracy in pelvic tumour resections, bringing osteotomy results closer to the parameters set in pre-operative planning, as compared with standard manual techniques.Cite this article: A. Sallent, M. Vicente, M. M. Reverté, A. Lopez, A. Rodríguez-Baeza, M. Pérez-Domínguez, R. Velez. How 3D patient-specific instruments improve accuracy of pelvic bone tumour resection in a cadaveric study. Bone Joint Res 2017;6:577-583. DOI: 10.1302/2046-3758.610.BJR-2017-0094.R1.

Anthropometric characteristics of the pubic arch and proper function of the defense mechanisms against hernia formation.

In 33 inguinal regions, we determined the anthropometric characteristics of the pubic arch and the anatomic structures of the suprainguinal space and assessed whether there is a relationship between anatomic features and function of the defense mechanisms. There was a low position of the pubic arch (pubic tubercle and interspinal line distance >75 mm) in 23 cases. The low-pubic-arch group showed a significantly longer inguinal ligament and a greater angle made by the superior border of the suprainguinal space and the inguinal ligament at its medial insertion. The position of the pubic arch correlated significantly with the diameter of the internal ring, the length of the inguinal ligament, and the angle made by the superior border of the suprainguinal space and the medial insertion of the inguinal ligament. A low pubic arch would represent an unfavorable condition for an adequate function of the anatomic defense mechanism against hernia.

Spontaneous ventriculostomy: report of three cases revealed by flow-sensitive phase-contrast cine MR imaging.

Spontaneous ventriculostomy is a rare condition that occurs with the spontaneous rupture of a ventricle, resulting in a communication between the ventricular system and the subarachnoid space. Three cases of spontaneous ventriculostomy through the floor of the third ventricle that occurred in cases of chronic obstructive hydrocephalus are presented. The communication was identified via flow-sensitive phase-contrast cine MR imaging. Spontaneous ventriculostomy is probably a result of a rupture of the normally thin membrane that forms the floor of the third ventricle and, with long-standing obstructive hydrocephalus, creates an internal drainage pathway that spontaneously compensates for the hydrocephalus.

Posterior fossa reconstruction: a surgical technique for the treatment of Chiari I malformation and Chiari I/syringomyelia complex--preliminary results and magnetic resonance imaging quantitative assessment of hindbrain migration.

Experimental models have shown that Chiari I malformation is a primary paraaxial mesodermal insufficiency occurring after the closure of the neural folds takes place. According to these hypotheses, a small posterior fossa caused by an underdeveloped occipital bone would be the primary factor in the formation of the hindbrain hernia. The main objective in the surgical treatment of Chiari I malformation and related syringomyelia is directed to restore normal cerebrospinal fluid dynamics at the craniovertebral junction. The most widely accepted surgical approach is to perform a craniovertebral decompression of the posterior fossa contents with or without a dural graft. It has been emphasized that suboccipital craniectomy should be small enough to avoid downward migration of the hindbrain into the craniectomy. This slump of the hindbrain has been verified by studies using postoperative assessment by magnetic resonance imaging. Our aim in this study is to present a modification of the conventional surgical technique, which we have called posterior fossa reconstruction (PFR). Ten patients were operated on using this technique and compared with a historical control group operated on with the classic approach of making a small suboccipital craniectomy, opening the arachnoid, and closing the dura with a graft. To evaluate the morphological results in both groups objectively, preoperative and postoperative measurements of the relative positions of the fastigium and upper pons above a basal line in the midsagittal T1-weighted magnetic resonance images were obtained. In those cases with syringomyelia, syringo-to-cord ratios were calculated. The mean age of the PFR group was 35 +/- 16 years (mean +/- SD); in the control group it was 35.2 +/- 12 years. In the PFR group, the formation of an artificial cisterna magna was observed in every case; it was observed in only one case in the control group. An upward migration of the cerebellum was seen in all cases in the PFR group, with a mean ascent of the fastigium of 6.2 mm. A significant downward migration of the cerebellum was observed in seven cases in the control group. No significant differences were found in both groups when comparing syringo-to-cord ratios. This leads us to conclude that PFR is more effective than conventional surgical approaches in restoring the normal morphology of the craniovertebral junction. This allows cranial ascent of the hindbrain verified by magnetic resonance imaging and good short-term clinical results. Because PFR is mainly an extraarachnoidal approach, complications related to surgery using this technique can be kept to a minimum.

Evaluation of cerebrovascular CO2-reactivity and autoregulation in patients with post-traumatic diffuse brain swelling (diffuse injury III).

The present study was undertaken to elucidate the status of autoregulation and CO2-reactivity soon after injury in patients with a post-traumatic diffuse bilateral brain swelling. A prospective study was carried out in 31 consecutively admitted patients with a severe head injury and a Diffuse Brain Injury type III, following the definition stated by the Traumatic Coma Data Bank classification. To evaluate CO2-reactivity, AVDO2 was measured before and after ventilator manipulations. Assuming a constant CMRO2 during the test, changes in 1/AVDO2 reflect changes in CBF. Patients with changes in estimated CBF below or equal to 1% were included in the impaired/abolished CO2-reactivity group. To test autoregulation, hypertension was induced using phenylephrine. Arterial and jugular blood samples were taken to calculate AVDO2 before and after a steady state of MABP was obtained. Cerebrovascular response to CO2 was globally preserved in all but two cases (6.5%). In contrast, autoregulation was globally preserved in 10 (32.3%) and impaired/abolished in 21 cases (67.7%). Our data do not support the premise that increasing cerebral perfusion pressure by inducing arterial hypertension is beneficial in those patients with a diffuse brain swelling in whom autoregulation is impaired or abolished. Clinical implications for treatment are discussed.

Is the reversed fourth dorsal metacarpal flap reliable?

We have carried out a study to determine if a flap based on vessels in the fourth metacarpal space could be used safely. We studied ten fresh cadaver specimens and used the flap in nine patients. In the anatomical study, we confirmed the presence of a suitable artery in nine out of the ten hands, arising from a piercing artery at the metacarpal bases, running distally under the fascia. The pivot point is located at the metacarpal heads, where the artery anastomoses to palmar branches and dorsal digital branches. In the clinical setting, the flap was reliable in eight patients. There was one case of flap necrosis. The flap seems to be reliable but several technical points are stressed to avoid complications.

[Bronchial arteries: anatomical and clinical studies and strategies in surgical approach]. / Arterie bronchiali. Studio anatomo-clinico e strategie di accesso chirurgico.

One of the most important and controversial aspects of thoracic surgery is due to the topographical and surgical anatomy of the vascular structures involving the mediastinum. The knowledge of the so-called "vascular time", in fact, allows to face more complicated surgical situations, typical of the most specialistic thoracic surgery. The bronchial arteries represent a paradigm of what we have just stated. The study of their anatomy (number, position, origin, distribution and relationships with the mediastinal structures) is of relevant importance, not only for the interest the bronchial vascular tree arises in tracheo-bronchial surgery and in pulmonary transplantology, but also for the knowledge of the pathogenesis of some processes regarding pulmonary and pleural pathologies. The aim of this paper is to evaluate the real clinical interest of bronchial arteries, with an analytic study of the anatomy of vessels, and with the possibility to show the most frequent and characteristic anomalies involving the origin and course of these arteries.

[Importance of morphostructural changes observed in cortical micro-vessels in patients who died after a severe head injury]. / Relevancia de las alteraciones morfoestructurales detectadas en la microvascularización de la corteza cerebral en pacientes fallecidos por traumatismo craneoencefálico grave.

INTRODUCTION: The development of secondary lesions in traumatic head injuries seems to be a determinative factor for the survival of these patients. Endothelium damage of cortical microvessels could be fundamental in the main secondary lesions as cerebral ischemia and intracranial hypertension. OBJECTIVES: To investigate which are the main morphological changes that can be observed in cortical microvessels from these patients. MATERIAL AND METHODS: We have studied 15 fresh human brains from subjects died after a severe head injury. The study has been carried out by scanning electron microscopy of vascular corrosion casts and confocal microscopy of histological sections after immunocytochemistry, as well as detection of apoptosis by TUNEL technique. RESULTS AND CONCLUSIONS: The most significant structural alterations were observed mainly on arterioles and capillaries of the middle and deep vascular zones of the cerebral cortex. Corrosion casts showed vessels with longitudinal folds, sunken surface with craters and flattened vessels with reduced lumen. Histological sections immunostained with MAS-336 also showed vessels with longitudinal folds and thinning of their vascular lumen, the presence of cytoplasmic round bodies and a thickening of endothelial cell membrane. TUNEL method revealed a positive staining of some endothelial cells. The structural alterations observed seem to reveal a situation of cellular damage of endothelium in the human cortical microvessels from these patients. It can be thought that this kind of lesions, as well as the secondary functional injury of the blood brain barrier, could play an important role in the development of secondary damage.

[Anatomic study of parapharyneal space]. / Estudio anatómico del espacio parafaríngeo.

The parapharyngeal space is considered the key space of the suprahioid neck, being essential to establish the origin and anatomic relations of the lesions of the profound neck. The descriptions of the fascial limits of the parapharyngeal space are variable in the litterature, reflecting some ambiguity in the manuals of anatomy and surgery. We have done a detailed study of this region, working on 5 cadavers, fixed in a solution of phenol and alcohol, and correlating the disection pieces with a radiologic study. The goal has been to improve our anatomic knowledge of the suprahioid neck, to be able to establish an anatomo-clinic-radiologic correlation of the lesions of this region, to be able to establish an differential diagnosis, predict possible ways of dissemination and facilitate the most proper surgical approach.

Mimicking microvascular alterations of human diabetic retinopathy: a challenge for the mouse models.

Although it has become acceptable that neuroretinal cells are also affected in diabetes, vascular lesions continue to be considered as the hallmarks of diabetic retinopathy. Animal models are essential for the understanding and treatment of human diabetic retinopathy, and the mouse is intensively used as a model because of its similarity to human and the possibility to be genetically modified. However, until today not all retinal vascular lesions developed in diabetic patients have been reproduced in diabetic mice, and the reasons for this are not completely understood. In this review, we will summarize retinal vascular lesions found in diabetic and diabetic-like mouse models and its comparison to human lesions. The goal is to provide insights to better understand human and mice differences and thus, to facilitate the development of new mouse models that mimic better human diabetic retinopathy.