Visão integrativa da dor em seu aspecto biopsicossocial / Integrative view of pain in its biopsychosocial aspect / Visión integradora del dolor en su vertiente biopsicosocial

Na definição padrão da medicina a nocicepção ou algesia é a transdução, condução e processamento de sinais nervosos aferentes gerados por nociceptores estimulados,resultando na percepção da dor. Os sinais de estímulos nocivos (mecânicos, térmicos ou químicos) são transmitidos principalmente através de dois tipos de nervos. As terminações nervosas das pequenas fibras mielinizadas a delta e as fibras C não mielinizadas estão localizadas na pele, tecido subcutâneo, periósteo, articulações, músculos e vísceras. As fibras beta mielinizadas, as maiores, normalmente transmitem estímulos não nocivos, como toque, vibração, pressão, movimento e propriocepção. No entanto, a entrada não nociva dessas fibras pode ser incorretamente processada em um sistema nervoso central alterado, resultando na percepção da dor (alodinia).

Coexistence of Straatsma syndrome without macular extension and abnormal ellipsoid zone / Coexistência da síndrome de Straatsma sem extensão macular e zona elipsoide anormal

ABSTRACT Myelinated retinal nerve fibers are rare congenital anomalies that appear as gray-white patches. They may be present in a syndrome characterized by ipsilateral myelinated retinal nerve fibers, myopia and amblyopia. The author reported an ellipsoid zone defect on spectral domain optical coherence tomography in a case of Straatsma syndrome without macular extension.

RESUMO Fibras nervosas retinais mielinizadas são anomalias congênitas raras que aparecem como manchas branco-acinzentadas. Eles podem se apresentar em uma síndrome caracterizada por fibras nervosas retinais mielinizadas ipsilaterais, miopia e ambliopia. O autor relatou um defeito na zona elipsoide na tomografia de coerência óptica de domínio espectral em um caso de síndrome de Straatsma sem extensão macular.

Straatsma syndrome / Síndrome de Straatsma

Abstract The presence of retinal myelinated nerve fibers is not a rare finding during routine examinations, and it is usually a benign and isolated finding. However, in some rare cases, it can be associated with other ophthalmological conditions. We describe a case of a patient with the triad myelin nerve fibers, myopia and ambliopia, which configures the Straatsma Syndrome.

Resumo A presença de fibras de mielina é um achado comum durante exames oftalmológicos de rotina. Na maior parte das vezes, tem caráter beningno e é um achado isolado. No entanto, em alguns raros casos, a presença de mielinização pode estar associada a outras condições oftalmológicas. Descrevemos um caso de paciente com a tríade presença de fibras nervosas retinianas mielinizadas, miopia, e ambliopia, configurando a síndrome de Straatsma.

140 Years of the Leçons sur l'histologie du système nerveux: the pioneering description of the nodes of Ranvier / 140 Anos da Leçons sur l'histologie du système nerveux: a descrição pioneira dos nodos de Ranvier

ABSTRACT This paper reviews aspects of the life and work of Professor Louis Ranvier 140 years after the publication of Leçons sur l'histologie du système nerveux, published in 1878, and shows the importance of the histological description of myelinated fibers of the nodes of Ranvier.

RESUMO Os autores apresentam uma revisão sobre aspectos da vida e obra do Professor Louis Ranvier 140 anos após a publicação de seu livro Leçons sur l'histologie du système nerveux publicado em 1878 e mostra a importância da descrição histológica nas fibras mielínicas dos nodos de Ranvier.

Foveosquisis miópica asociada al Síndrome de Straatsma / Myopic foveoschisis associated with Straatsma's syndrome

RESUMEN Este reporte describe la presentación concomitante de foveosquisis miópica y fibras de mielina en una paciente con miopía elevada. La primera puede ser un hallazgo incidental, pero no infrecuente en pacientes con miopía elevada, y causa pérdida visual central severa. La segunda es infrecuente, y en casos muy raros se presenta asociada a miopía ipsilateral y estrabismo. Ambas entidades deben incluirse en el diagnóstico diferencial de un paciente alto miope con disminución de la visión central. La tomografía de coherencia óptica es el medio auxiliar de elección(AU)

ABSTRACT This case report describes the concomitant presentation of myopic foveoschisis and myelinated retinal nerve fibers in a patient with elevated myopia. The myopic foveoschisis may be an incidental but not uncommon finding in highly myopic eyes, leading to severe central vision loss. Myelinated retinal nerve fibers are infrequent and in rarely cases they are associated with ipsilateral myopia and strabismus. Both entities should be including as differential diagnosis of central vision loss in high myopia, and optic coherence tomography is the leading as auxiliary test(AU)

A Case of Schwannoma Originated from the Posterior Nasal Septum / 대한이비인후과학회지

Schwannomas are slow-growing, benign neurogenic tumors arising from the sheath of myelinated nerve fibers. They usually occur in the head and neck region. Only 4% of schwannomas found in the head and neck region originate in the sinonasal tract. Schwannoma of the nasal septum is rarer, and only few cases have been previously reported in the literature. We experienced a rare case of the schwannoma of the posterior nasal septum in a 71-year-old woman. She was treated successfully by transnasal endoscopic surgery. No recurrence was detected within 18 months follow-up period.

Mechanisms of Cervical Spine Disc Injury under Cyclic Loading

STUDY DESIGN: Determination of human cervical spine disc response under cyclic loading. PURPOSE: To explain the potential mechanisms of intervertebral disc injury caused by cyclic loading. OVERVIEW OF LITERATURE: Certain occupational environments in civilian and military populations may affect the cervical spine of individuals by cyclic loading. Research on this mechanism is scarce. METHODS: Here, we developed a finite element model of the human C4–C5 disc. It comprised endplates, five layers of fibers, a nucleus, and an annulus ground substance. The endplates, ground substance, and annular fibers were modeled with elastic, hyperviscoelastic, and hyper-elastic materials, respectively. We subjected the disc to compressive loading (150 N) for 10,000 cycles at frequencies of 2 Hz (low) and 4 Hz (high). We measured disc displacements over the entire loading period. We obtained maximum and minimum principal stress and strain and von Mises stress distributions at both frequencies for all components. Further, we used contours to infer potential mechanisms of internal load transfer within the disc components. RESULTS: The points of the model disc displacement versus the loading cycles were within the experimental corridors for both frequencies. The principal stresses were higher in the ground matrix, maximum stress was higher in the anterior and posterior annular regions, and minimum stress was higher along the superior and inferior peripheries. The maximum principal strains were radially directed, whereas the minimum principal strains were axially/obliquely directed. The stresses in the fibers were greater and concentrated in the posterolateral regions in the innermost layer. CONCLUSIONS: Disc displacement was lower at high frequency, thus exhibiting strain rate stiffening and explaining stress accumulation at superior and interior peripheries. Greater stresses and strains at the boundaries explain disc injuries, such as delamination. The greater development of stresses in the innermost annular fiber layer (migrating toward the posterolateral regions) explains disc prolapse.

Straatsma syndrome: two case reports / Síndrome de Straatsma: dois relatos de caso

Abstract This article reports two cases of Straatsma Syndrome, a rare disease, emphasizing its clinical features that inclued myopia, strabismus and amblyopia associated with persistent myelinated fibers in the retina. Ophthalmic examination, color retinography and optical coherence tomography were performed.

Resumo Este artigo relata dois casos de síndrome de Straatsma, uma doença rara, enfatizando suas características clínicas que incluem miopia, estrabismo e ambliopia associada a persistência de fibras de mielina na retina. Foram realizados exame oftalmológico, retinografia e tomografia de coerência óptica.

Morgellons Disease

Morgellons disease is a rare disease with unknown etiology. Herein, we report the first case of Morgellons disease in Korea. A 30-year-old woman presented with a 2-month history of pruritic erythematous patches and erosions on the arms, hands, and chin. She insisted that she had fiber-like materials under her skin, which she had observed through a magnifying device. We performed skin biopsy, and observed a fiber extruding from the dermal side of the specimen. Histopathological examination showed only mild lymphocytic infiltration, and failed to reveal evidence of any microorganism. The polymerase chain reaction for Borrelia burgdorferi was negative in her serum.

Hind limb sensory innervation in rats: comparison between sural and saphenous nerve morphometry / Inervación sensorial de los miembros posteriores en ratas: comparación morfométrica entre los nervios sural y safeno

Although numerous studies investigate sensory recovery of the hind paw of the rat after nerve damage, still no comprehensive overview of its normal innervation is present in the literature. We investigated the morphometry of myelinated fibers in the sural and saphenous nerves and analyzed their size distributions in young rats. Six 30-day-old female Wistar rats were perfused with 2.5% glutaraldehyde and their right and left sural and saphenous nerves were prepared for light microscopy and morphometry. Morphometric data were compared between segments (proximal versus distal) and sides (right versus left) for the same nerves. Also, segments from right or left sides were compared between nerves (sural versus saphenous). Both, the sural and saphenous nerves, exhibited proximal to distal symmetry on both sides as well as left-right symmetry. Histograms of the diameter of the myelinated fibers were unimodal in both nerves, regardless of segments or sides with the peaks of the fibers size occurring between 2.5 and 4.0 µm. The axon distributions reflected the myelinated fiber distributions, with the sural and saphenous nerves peaking between 1.5 and 2.0 µm. The G ratio (the ratio between the axon and fiber diameters) distributions were also unimodal, with peaks at 0.6 for both nerves. This study contributes to the literature with information on the myelinated fibers morphometry from the two sensory nerves responsible for the rat hind limb innervation. This information is valuable for a better understanding of the possible contribution of collateral sprouting from the sural or saphenous nerves on the paw sensory territory recovery observed after one of these nerves is damaged.

Aunque numerosos estudios investigan la recuperación sensorial del miembro pélvico o posterior de la rata después del daño en los nervios, aún no existe en la literatura una visión global de su inervación normal. Investigamos la morfometría de fibras mielínicas de los nervios sural y safeno y analizamos sus distribuciones de tamaño en ratas jóvenes. Seis ratas Wistar de 30 días de edad fueron perfundidas con 2,5% de glutaraldehído, se prepararon los nervios sural y safeno derecho e izquierdo para microscopía de luz y morfometría. Datos morfométricos fueron comparados entre los segmentos (proximal vs distal) y laterales (derecho vs izquierdo) para los mismos nervios. Además, los segmentos de los lados derecho e izquierdo se compararon entre los nervios (sural vs safeno). Ambos nervios sural y safeno exhibieron una simetría proximal a distal en ambos lados, así como una simetría izquierda-derecha. Histogramas del diámetro de las fibras mielinizadas eran unimodales en ambos nervios, independientemente de los segmentos o de los lados, siendo los peaks del tamaño de las fibras entre 2,5 y 4,0 micras. Las distribuciones de los axones reflejan las distribuciones de fibras mielinizadas, de los nervios sural y safeno que alcanzaban entre 1,5 and 2,0 µm. La relación de G (relación entre los diámetros de los axones y de fibra) eran también unimodales, alcanzando 0,6 para ambos nervios. Este estudio contribuye a la literatura con los datos de la morfometría de fibras mielinizadas de ambos nervios sensoriales responsables de la inervación de la extremidad pélvica de la rata. Esta información es valiosa para una mejor comprensión de los nervios sural y safeno en la recuperación sensorial del miembro después de que uno de estos nervios ha sido dañado.

Combined polyglycolic acid tube and autografting versus autografting or polyglycolic acid tube alone. A comparative study of peripheral nerve regeneration in rats

PURPOSE: To compare sciatic nerve regeneration in rats using three different techniques of repair. METHODS: Fifteen isogonics rats were divided into three groups according to the method used to repair a 5-mm long defect created in the sciatic nerve: autogenous graft (Group A), polyglycolic acid tube (PGAt) (Group B), and of the association of PGAt with the graft (Group C). Histological analysis, regenerated myelinated axon number count and functional analysis were used to compare after six weeks. RESULTS: There was no difference in fiber diameter and degree of myelinization presented by Groups A, B and C. Group B presented the lowest number of regenerated axons. The groups did not display any significant functional difference after walking track analysis (p<0.05). CONCLUSION: No differences between the three groups in terms of functional recovery, although there were histological differences among them. .

A Case of Recurrent and Multiple Schwannomas in the Caudal Septum

Schwannomas are benign neoplasms arising from the sheath of myelinated nerve fibers and may occur in any part of the body. They mostly occur in the head and neck region, accounting for about 25% to 45% of all cases. The eighth cranial nerve is the most common site of origin. About 4% of all head and neck schwannomas originate in the nasal cavity and paranasal sinuses. The best treatment of schwannomas is surgical excision. Since it is an encapsulated tumor, difficultly is rarely encountered in its complete removal, and recurrence is unlikely. We present a unique and rare case of a 71-year-old man with a recurrent septal mass, finally diagnosed as a schwannoma, with a review of the literature.

Difficult intubation using intubating laryngeal mask airway in conjunction with a fiber optic bronchoscope

When anesthesiologists encounter conditions in which intubation is not possible using a conventional direct laryngoscope, they can consider using other available techniques and devices such as fiber optic bronchoscope (FOB)-guided intubation, a laryngeal mask airway (LMA), intubating LMA (ILMA), a light wand, and the Combitube. FOB-guided intubation is frequently utilized in predicted difficult airway cases and is generally performed when the patient is awake to enable easier access to the trachea. An LMA can be introduced to ventilate the patient with relative ease, while an ILMA can be used for definite endotracheal intubation. However, occasionally, an endotracheal tube (ETT) cannot pass through the larynx, despite successful introduction of a FOB into the trachea and placement of an ILMA by the anesthesiologist. Therefore, we initially introduced an ILMA for emergent ventilation, followed by successful insertion of an ETT under FOB guidance. In this report, we describe three cases of difficult intubation using a FOB and ILMA combination approach.

Difficult intubation using intubating laryngeal mask airway in conjunction with a fiber optic bronchoscope

When anesthesiologists encounter conditions in which intubation is not possible using a conventional direct laryngoscope, they can consider using other available techniques and devices such as fiber optic bronchoscope (FOB)-guided intubation, a laryngeal mask airway (LMA), intubating LMA (ILMA), a light wand, and the Combitube. FOB-guided intubation is frequently utilized in predicted difficult airway cases and is generally performed when the patient is awake to enable easier access to the trachea. An LMA can be introduced to ventilate the patient with relative ease, while an ILMA can be used for definite endotracheal intubation. However, occasionally, an endotracheal tube (ETT) cannot pass through the larynx, despite successful introduction of a FOB into the trachea and placement of an ILMA by the anesthesiologist. Therefore, we initially introduced an ILMA for emergent ventilation, followed by successful insertion of an ETT under FOB guidance. In this report, we describe three cases of difficult intubation using a FOB and ILMA combination approach.

A Case of Cauda Equina Syndrome in Early-Onset Chronic Inflammatory Demyelinating Polyneuropathy Clinically Similar to Charcot-Marie-Tooth Disease Type 1

To present a case of cauda equina syndrome (CES) caused by chronic inflammatory demyelinating polyneuropathy (CIDP) which seemed clinically similar to Charcot-Marie-Tooth disease type1 (CMT1). CIDP is an immune-mediated polyneuropathy, either progressive or relapsing-remitting. It is a non-hereditary disorder characterized by symmetrical motor and sensory deficits. Rarely, spinal nerve roots can be involved, leading to CES by hypertrophic cauda equina. A 34-year-old man presented with low back pain, radicular pain, bilateral lower-extremity weakness, urinary incontinence, and constipation. He had had musculoskeletal deformities, such as hammertoes and pes cavus, since age 10. Lumbar spine magnetic resonance imaging showed diffuse thickening of the cauda equina. Electrophysiological testing showed increased distal latency, conduction blocks, temporal dispersion, and severe nerve conduction velocity slowing (3 m/s). We were not able to find genetic mutations at the PMP 22, MPZ, PRX, and EGR2 genes. The pathologic findings of the sural nerve biopsy revealed thinly myelinated nerve fibers with Schwann cells proliferation. We performed a decompressive laminectomy, intravenous IgG (IV-IgG) and oral steroid. At 1 week after surgery, most of his symptoms showed marked improvements except foot deformities. There was no relapse or aggravation of disease for 3 years. We diagnosed the case as an early-onset CIDP with cauda equine syndrome, whose initial clinical findings were similar to those of CMT1, and successfully managed with decompressive laminectomy, IV-IgG and oral steroid.

A Case of Vidian Nerve Schwannoma: Resection by Endoscopic Sinus Surgery / 대한이비인후과학회지

Schwannoma is a benign tumor arising from the sheath of myelinated nerve fibers and may occur in any part of the body. However, a vidian nerve schwannoma is extremely rare. A 41 year-old man has experienced an occipital area headache and posterior neck stiffness for 2 weeks. Brain computed tomography (CT) angiography, magnetic resonance image revealed lobulated soft tissue density mass in left sphenoid sinus with upward displacement of sphenoid sinus floor and pressure erosion of sphenoid sinus and petrous apex. Ostiomeatal unit CT scan showed a 28x16 mm sized mass filling the left pterygoid canal. The mass was resected using endoscopic sinus surgery. The mass was confirmed as schwannoma. We report a case of vidian nerve schwan-noma that was treated by endoscopic sinus surgery.

Possible Local Stem Cells Activation by Microcurrent Application in Experimentally Injured Soleus Muscle

BACKGROUND: Severe injuries in skeletal muscle result in muscle weakness that delays recovery and contribute to progressive decline in muscle function. Microcurrent therapy (MCT) is a novel treatment method used in soft tissue injury and tissue regeneration therapy. The regenerative capacity of skeletal muscle tissue resides in satellite cells, the quiescent adult stem cells. AIM: The present work aimed at investigating the relation between microcurrent therapy and local stem cells in regeneration of induced skeletal muscle injury in albino rat. MATERIALS AND METHODS: Twenty six adult male albino rats were divided into Sham group, Injury group (I): subjected to soleus muscle injury and subdivided into subgroups I1 & I2 sacrificed 2 and 4 weeks after injury respectively. Microcurrent group (M): subjected to muscle injury and micro-current was applied. The animals were subdivided into subgroups M1 and M2 sacrificed 2 and 4 weeks after injury. Histological, immunohistochemical and morphometric studies were performed. RESULTS: Atypical fibers widely separated by infiltrating cells and strong acidophilic sarcoplasm with focal vacuolations were found in injury group. In M1 subgroup few atypical fibers were found. In M2 subgroup multiple typical fibers were detected. A significant decrease in the mean area of atypical fibers, a significant increase in the mean area% of alpha SMA+ve cells and that of CD34+ve cells were found in microcurrent group compared to injury group. CONCLUSIONS: A definite therapeutic effect of the microcurrent was found on induced skeletal muscle injury. This effect was proved to be related to satellite cell activation.

Significance of increased CIMT with coexisting carotid plaques in cerebral white matter lesions in elders / 华中科技大学学报（医学）（英德文版）

It is very common that increased carotid intima media thickness (CIMT) and carotid plaque coexist in a single subject in elderly patients with white matter lesions (WMLs). In this study we investigated whether the coexistence of increased CIMT and carotid plaque is more strongly associated with the presence and extent of WMLs than either alone. All patients were classified into 1 of the following 4 groups: without either increased CIMT (I) or carotid plaque (P): I(-)P(-); with only increased CIMT: I(+)P(-); with only carotid plaque: I(-)P(+); and with both increased CIMT and carotid plaque: I(+)P(+). The presence and severity of periventricular WMLs (PWMLs) and deep WMLs (DWMLs) were assessed and the prevalence of MRI findings by the Cochran-Armitage trend test was calculated. The characteristics of subjects showed that the percentages of patients with increased CIMT and carotid plaque in the DWMLs group and the PWMLs group were significantly higher than those without WMLs group. Both DWMLs and PWMLs were strongly associated with age, carotid plaque and CIMT. Furthermore, the Cochran-Armitage trend test indicated that the prevalence of MRI findings of PWMLs and DWMLs increased in the order of I(-)P(-)< I(+)P(-)< I(-)P(+)< I(+)P(+) (P<0.0001). For the patients with DWMLs, the grades of both I(+)P(-) and I(+)P(+) were increased significantly compared to I(-)P(-) (P<0.0025, P<0.05, respectively) without such a difference found in patients with PWMLs. Our results suggested that the coexistence of increased CIMT and carotid plaque is most closely associated with WMLs, and that increased CIMT is associated with the severity of DWMLs, whereas carotid plaque is related to the presence of WMLs.

Comparison of high-resolution and standard zoom imaging modes in cone beam computed tomography for detection of longitudinal root fracture: An in vitro study

PURPOSE: The purpose of this study was to compare the efficacy of two imaging modes in a cone beam computed tomography (CBCT) system in detecting root fracture in endodontically-treated teeth with fiber posts or screw posts by selecting two fields of view. MATERIALS AND METHODS: In this study, 78 endodontically-treated single canal premolars were included. A post space was created in all of them. Then the teeth were randomly set in one of 6 artificial dental arches. In 39 of the 78 teeth set in the 6 dental arches, a root fracture was intentionally created. Next, a fiber post and a screw post were cemented into 26 teeth having equal the root fractures. High resolution (HiRes) and standard zoom images were provided by a CBCT device. Upon considering the reconstructed images, two observers in agreement with each other confirmed the presence or absence of root fracture. A McNemar test was used for comparing the results of the two modes. RESULTS: The frequency of making a correct diagnosis using the HiRes zoom imaging mode was 71.8% and in standard zoom was 59%. The overall sensitivity and specificity in diagnosing root fracture in the HiRes mode were 71.79% and 46.15% and in the standard zoom modes were 58.97% and 33.33%, respectively. CONCLUSION: There were no significant differences between the diagnostic values of the two imaging modes used in the diagnosis of root fracture or in the presence of root canal restorations. In both modes, the most true-positive results were reported in the post space group.

Síndrome de mielinización de fibras nerviosas retinales, miopía y ambliopía / Syndrome of myelinated retinal nerve fibers, myopia and amblyopia

Las fibras de mielina intraoculares se presentan desde el nacimiento y suelen localizarse alrededor de la papila. El síndrome de mielinización de las fibras nerviosas retinales fue descrito por Virchow por primera vez en 1856. Este aparece como parches estriados, blanco o blanco grisáceos con los bordes imprecisos y plumosos siguiendo una configuración coincidente con la distribución de las fibras nerviosas retinales. Se presenta una paciente femenina de 4 años que es traída a consulta por desviación del ojo derecho. En el examen oftalmológico se detecta una agudeza visual con corrección de 0,1 y la oftalmoscopia confirma la mielinización de las fibras nerviosas retinales. En estos pacientes se asocia frecuentemente la miopía y ambliopía. A pesar de los pobres resultados visuales y ante la ausencia de otras terapias disponibles existe tendencia a tratamiento agresivo para la ambliopía, aunque en la literatura esto es aún controversial

The intraocular myelin fibers emerge since one's birth and it is usually located around the papilla. The syndrome of myelinated retinal nerve fibers was described for the first time by Virchow in 1856. This appears in the form of grooved patches, white or grayish white with imprecise and feathery borders following a coincident configuration with the distribution of the retinal nerve fibers. A four years-old girl who was taken to the doctor's office because she presented with right eye deviation. In the ophthalmologic exam, the best corrected visual acuity was 0.1 and the ophthalmoscopy confirmed myelinated retinal nerve fibers. Myopia and amblyopia were often associated in these patients. In spite of the poor visual results and the lack of other available therapies, specialists tend to apply aggressive treatment for amblyopia, although this procedure is still controversial in the medical literature