How to perform the Wiltse posterolateral spinal approach: Technical note.

BACKGROUND: The paraspinal, posterolateral, or Wiltse approach is an old technique that observes the principles of an MIS procedure. The aim of this study was to provide a step-by-step description from the literature of the Wiltse paraspinal approach and analyze its main advantages and limitations. METHODS: Here, we provide a step-by-step description of the Wiltse approach. Utilizing PubMed and Lilacs and the Mesh terms "Wiltse approach," "paraspinal approach," "muscle sparing approach," and "lumbar spine," we identified 10 papers. We then put together, based on these publications, a step-by-step analysis of the preparation, patient positioning, skin incision, fascial opening, dissection, bone identification, retractors, deperiostization, decompression, discectomy, instrumentation, arthrodesis, and closure for the Wiltse technique. RESULTS: Most papers underscored the minimally invasive aspects of the typical Wiltse approach. Advantages included minimal intraoperative bleeding, a shorter hospital length of stay, and a low infection rate. CONCLUSION: The classical approach described by Wiltse is essentially minimally invasive, sparing both the muscle planes and soft tissues, allowing for ample far lateral lumbar decompression, including discectomy and fusion, with a low complication rate.

Minimally invasive approaches for thoracic decompression from discectomy to corpectomy.

Surgical approaches to the thoracic spine have evolved in recent decades with the development of advanced instrumentation techniques and an increased emphasis on reducing surgical morbidity. Multiple methods to access this area have been described, from a conventional open to a more minimally invasive approach, such as anterior-based, via supra- or transmanubrium, via thoracoscopy, lateral-based approach, extreme lateral mini-thoracotomy, and dorsolateral approaches, transpedicular, costotransversectomy and the lateral extracavitary access. The technique used is often determined by the affected spinal level, pathological process, and surgeon preference. Each of these approaches requires expertise in the specific technique, and has its own complication profile. Over time, these techniques have undergone improvement to limit approach-related morbidity and minimize soft tissue dissection, resulting in better patient outcomes. These different approaches present distinct advantages and disadvantages for which a thorough understanding of the regional anatomy is required to avoid approach-related complications. For these reasons, surgeon experience and confidence in the various techniques are major factors in the decision-making process and patient outcomes.

Anaplastic meningioma: case report.

Intracranial meningiomas continue to challenge our best clinical efforts to eliminate them once discovered and deemed appropriate for treatment. Malignant meningiomas constitute 10% to 15% of all meningiomas and limited information exists regarding adjuvant treatment. The external whole brain irradiation is recommended. Traditional chemotherapy has proven ineffective; thus, new chemotherapeutic agents and new methods of delivery should be developed. Immunotherapy may be considered for patients with malignant meningiomas when all others previous treatment have failed. We report a case of anaplastic papillary meningioma. A 67-year-old man presented with partial complex seizures, headache and aggressiveness. A computerized tomography and magnetic resonance image demonstrated a large left temporo-occipital mass with diffuse contrast enhancement and extensive surrounding edema. A left temporo-occipital flap was performed. The tumor and the infiltrated dura were radically removed. Postoperatively, the patient remained neurologically intact. The treatment was complemented by external whole brain radiation.

Infrasellar craniopharyngioma: case report.

We report a case of infrasellar craniopharyngioma in a 34 year-old woman who presented with progressive headache and diplopia. Computed tomographic and magnetic resonance images showed a heterogeneous tumor originating from the sphenoid bone with ethmoid sinus and sella turcica extension. A sublabial rhinoseptal transsphenoidal surgery was performed. Craniopharyngiomas with infrasellar development are very rare. Infrasellar craniopharyngioma is uncommon, thirty-five cases has been reported in literature. The embryology, clinical features and radiographic investigation of these tumors are discussed.

A rare case of intramedullary lipoma associated with cyst.

Intramedullary lipomas are benign tumours of the spinal cord corresponding to 1% of all primitive intramedullary tumours. We report a rare case of "true" intramedullary lipoma associated with cyst. The patient underwent subtotal resection and the diagnosis was made by histopathological examination. There was postoperative neurological improvement.

Intracerebral clysis in a rat glioma model.

OBJECTIVE: Intracerebral clysis (ICC) is a new term we use to describe convection-enhanced microinfusion into the brain. This study establishes baseline parameters for preclinical, in vivo, drug investigations using ICC in a rat glioma model. METHODS: Intracranial pressure was measured, with an intraparenchymal fiber-optic catheter, in male Fischer rats 10, 15, 20, and 25 days after implantation of C6 glioma cells in the right frontal lobe (n = 80) and in control rats without tumor (n = 20), before and during ICC. A 25% albumin solution (100 microl) was infused through an intratumoral catheter at 0.5, 1.0, 2.0, 3.0, and 4.0 microl/min. Infusate distribution was assessed by infusion of fluorescein isothiocyanate-dextran (Mr 20,000), using the aforementioned parameters (n = 36). Brains were sectioned and photographed under ultraviolet light, and distribution was calculated by computer analysis (NIH Image for Macintosh). Safe effective drug distribution was demonstrated by measuring tumor sizes and apoptosis in animals treated with N,N'-bis(2-chloroethyl)-N-nitrosourea via ICC, compared with untreated controls. Magnetic resonance imaging noninvasively confirmed tumor growth before treatment. RESULTS: Intracranial pressure increased with tumor progression, from 5.5 mm Hg at baseline to 12.95 mm Hg on Day 25 after tumor cell implantation. Intracranial pressure during ICC ranged from 5 to 21 mm Hg and was correlated with increasing infusion volumes and increasing rates of infusion. No toxicity was observed, except at the higher ends of the tumor size and volume ranges. Fluorescein isothiocyanate-dextran distribution was greater with larger infusion volumes (30 microl versus 10 microl, n = 8, P < 0.05). No significant differences in distribution were observed when different infusion rates were compared while the volume was kept constant. At tolerated flow rates, the volumes of distribution were sufficient to promote adequate drug delivery to tumors. N,N'-Bis(2-chloroethyl)-N-nitrosourea treatment resulted in significant decreases in tumor size, compared with untreated controls. CONCLUSION: The C6 glioma model can be easily modified to study aspects of interstitial delivery via ICC and the application of ICC to the screening of potential antitumor agents for safety and efficacy.

Linkage Arrangement of RFLP loci in progenies from crosses between doubled haploid Asparagus officinalis L. clones.

A preliminary genetic map of the dioecious species Asparagus officinalis L. (2n = 20) has been constructed on the basis of restriction fragment length polymorphism (RFLP) and isozyme marker data. With DNA samples digested with either EcoRI or HindIII 61 out of 148 probes (41%) identified RFLPs in six families of doubled haploid lines obtained through anther culture. A higher level of polymorphism (65%) was observed when a single family was screened for RFLPs using six distinct restriction enzymes. Segregation analysis of the BC progenies (40-80 individuals) resulted in a 418-cM extended map comprising 43 markers: 39 RFLPs, three isozymes and one morphological (sex). These markers are clustered in 12 linkage groups and four of them exhibited significant deviations from the expected 1∶1 ratio. One isozyme and three RFLP markers were assigned to the sex chromosome.

Isozyme gene markers in the dioecious species Asparagus officinalis L.

Extracts from phylloclads of Asparagus officinails were electrophoretically analyzed for isozyme polymorphism. Fourteen enzyme systems were examined using four buffer systems: seven enzymes (acid phosphatase, catalase, glutamate-oxaloacetate transaminase, isocitrate dehydrogenase, malate dehydrogenase, peroxidase, and 6-phosphogluconate dehydrogenase) exhibited clear and consistent banding patterns. Isozyme polymorphism was studied in seven pairs of male and female doubled haploids and in their male F1s. Segregation of polymorphic loci was examined in the backcross progenies and was found to be consistent with a simple Mendelian inheritance in all cases, except for three anodical peroxidases, where two factors have been hypothesized. No linkage could be found between isozyme markers that were segregating in the same cross, but association was demonstrated between one malate dehydrogenase locus and the sex determining genes. The availability of isozyme markers may be useful in breeding and, in particular, the localization of one malate dehydrogenase locus on the sex chromosomes may be helpful in mapping the sex genes.

Liver morphology with enphasis on bile ducts changes and survival analysis in mice submitted to multiple Schistosoma mansoni infections and chemotherapy

Numa tentativa de estar o mais próximo possível a pacientes infectados e tratados nas áreas endêmicas de esquistosomose (S. mansoni) e também para obter um período mais longo de seguimento, camundongos foram repetidamente infectado com um número baixo de cercarias. Dados de sobrevivência e variáveis histológicas tais como granuloma esquistosomótico, alteraçöes portais, necrose hepatocelular, regeneraçäo hepática, pigmento esquistosomótico, fibrose periductal e principalmente, alteraçöes dos ductos biliares foram analisados nos animais infectados tratados e näo tratados. Aa terapêutica por oxamniquina ns animais repetidamente infectados prolonga a sobrevivência de maneira singificante (Chi-quadrado 9,24, p = 0,0024), portanto confirmando resultados anteriores com um modelo semelhante mas com um período mais curto de seguimento. Ainda, a mortalidadade decresce rapidamente depois do tratamento, sugerindo uma abrupta reduçäo na gravidade das lesöes hepáticas. O fígado foi anida estudados sob o ponto de vista morfológico imunohistoquímico. Fibrose portal, com um quadro que lembra a fibrose humana do tipo Symmers está presente na fase tardia da infecçäo. As alteraçöes de ductos biliares säo muito próximas daquelas descritas na esquistosomose manônica humana. Antígeno esquistomótico foi observado e, uma célula isolada do revestimento alterado de ductos biliares. A patogênese das alteraçöes ductais e sua possível relaçäo com a infecçäo parasitária e/ou seus antígenos foi discutida

Liver morphology with emphasis on bile ducts changes and survival analysis in mice submitted to multiple Schistosoma mansoni infections and chemotherapy.

In an attempt to be as close as possible to the infected and treated patients of the endemic areas of schistosomiasis (S. mansoni) and in order to achieve a long period of follow-up, mice were repeatedly infected with a low number of cercariae. Survival data and histological variables such as schistosomal granuloma, portal changes, hepatocellular necrosis, hepatocellular regeneration, schistosomotic pigment, periductal fibrosis and chiefly bile ducts changes were analysed in the infected treated and non treated mice. Oxamniquine chemotherapy in repeatedly infected mice prolonged survival significantly when compared to non-treated animals (chi-square 9.24, p = 0.0024), thus confirming previous results with a similar experimental model but with a shorter term follow-up. Furthermore, mortality decreased rapidly after treatment suggesting an abrupt reduction in the severity of hepatic lesions. A morphological and immunohistochemical study of the liver was carried out. Portal fibrosis, with a pattern resembling human Symmers fibrosis was present at a late phase in the infected animals. Bile duct lesions were quite close to those described in human Mansonian schistosomiasis. Schistosomal antigen was observed in one isolated altered bile duct cell. The pathogenesis of the bile duct changes and its relation to the parasite infection and/or their antigens are discussed.