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<p>During brain activity neurons release the major excitatory transmitter glutamate, which is taken up by astrocytes and converted to glutamine. Glutamine returns to neurons for re-conversion to glutamate. This glutamate-glutamine cycle is energy demanding. Glutamate turnover in injured brain was studied using an animal iron-induced posttraumatic epilepsy model and using neurointensive care data from 33 patients with spontaneous subarachnoid hemorrhage (SAH). Immunoblotting revealed that the functional form of the major astrocytic glutamate uptake protein GLT-1 was decreased 1-5 days following a cortical epileptogenic iron-injection, presumably due to oxidation-induced aggregation. Using microdialysis it was shown that the GLT-1 decrease was associated with increased interstitial glutamate levels and decreased interstitial glutamine levels. The results indicate a possible posttraumatic and post-stroke epileptogenic mechanism. Analysing 3600 microdialysis hours from patients it was found that the interstitial lactate/pyruvate (L/P) ratio correlate with the glutamine/glutamate ratio (r =-0.66). This correlation was as strong as the correlation between L/P and glutamate (r=0.68) and between lactate and glutamate (r=0.65). Pyruvate and glutamine correlated linearly (r=0.52). Energy failure periods, defined as L/P>40, were associated with high interstitial glutamate levels. Glutamine increased or decreased during energy failure periods depending on pyruvate. Energy failure periods were clinically associated with delayed ischemic neurological deficits (DIND) or development of radiologically verified infarcts, confirming that L/P>40 is a pathological microdialysis pattern that can predict ischemic deterioration after SAH. DIND-associated microdialysis patterns were L/P elevations and surges in interstitial glutamine. Glutamine and pyruvate correlated with the cerebral perfusion pressure (r=0.25, r=0.24). Glutamine and the glutamine/glutamate ratio correlated with the intracranial pressure (r=-0.29, r=0.40). Glutamine surges appeared upon substantial lowering of the intracranial pressure by increased cerebrospinal fluid drainage. Increased interstitial glutamine and pyruvate levels may reflect augmented astrocytic glycolysis in recovering brain tissue with increased energy demand due to a high glutamate-glutamine turnover.</p>

The historical development, current practice, and the future of interventional neuroradiology are intricately linked to the advancements in the imaging and devices used for neuroendovascular treatments. This thesis explores the advanced imaging potential of the C-arm imaging systems used in the neurointerventional suite and investigates the initial clinical experience with a new flow diverter device to treat the intracranial aneurysms. A cohort of aneurysmal SAH patients who developed delayed cerebral ischaemia (DCI) were prospectively studied with a new parenchymal blood volume (PBV) research protocol C-arm CT examination concurrent with a magnetic resonance (MR) imaging examination that included perfusion and diffusion weighted sequences. Using a robust quantitative volume-of-interest analysis, it was demonstrated that C-arm CT PBV measurements are in agreement with MR-PWI CBV and CBF, and the PBV represents a composite perfusion parameter with both blood-flow (&asymp;60&percnt;) and blood-volume (&asymp;40&percnt;) weightings. Subsequently, using a voxel-wise ROC curve analysis and MR-DWI, it was shown that using optimal thresholds, C-arm CT PBV measurements allow reliable demarcation of the irreversibly infarcted parenchyma. For evaluation of ischaemic parenchyma, the PBV measurements were reliable for moderate-to-severe ischaemia but were prone to underestimate the mild-to-moderate ischaemia. A catalogue of reference mean PBV measurements was then created for various anatomical regions encompassing the whole brain after excluding any locations with ongoing ischaemia or infarction. Next, using an ROI-based analysis of the C-arm CT projection data, steady-state contrast concentration assumption underlying the PBV calculations was investigated. It was demonstrated that for clinical scans, the ideal steady-state assumption is not fully met, however, for a large majority of C-arm CT examinations the temporal characteristics of TDCs closely approximate the expected ideal steady-state. The degree to which the TDC of a C-arm CT scan approximates the ideal steady-state was found to influence the resulting PBV measurements and their agreement to MR-CBV. Moreover, the temporal characteristics of TDCs showed inter-subject variation. Finally, the C-arm CT cross-sectional soft tissue images were demonstrated to be of adequate quality for the assessment of ventricles and for the detection of procedural vessel rupture. These findings advance the understanding of the nature of PBV parameter, establish the optimal PBV thresholds for infarction, provide reference PBV measurements, and highlight the limitations of C-arm CT PBV imaging. The work is of considerable clinical significance and has implications for implementation of C-arm CT PBV imaging in the interventional suite for management of patients with acute brain ischaemia. In regards to the initial clinical experience with the flow diversion treatment of intracranial aneurysms, the procedural, angiographic, and clinical outcomes were studied. Several pertinent technical and clinical issues were highlighted for this new treatment approach. Based on the observations made during this work, a new grading schema was then developed to monitor the angiographic outcomes after flow diversion treatment. Using the angiographic data for patients treated with FD, the new grading schema was demonstrated to be sufficiently sensitive to register gradual aneurysm occlusion and evaluate parent artery patency, with an excellent inter-rater reliability and applicability to various aneurysm morphologies. This work (largest multi-centre series at the time of its publication) informed the interventional neuroradiology community about the safety, efficacy, and outcomes of flow diversion treatment. Additionally, it provided a sensitive and reliable scale to evaluate the angiographic outcomes after flow diversion treatment, in both research and clinical practice.

Introdução: A alta incidência de oclusão incompleta e recanalização dos aneurismas intracranianos de colo largo tratados por via endovascular levaram ao desenvolvimento de novas técnicas, entre elas o uso do Onyx ®. Objetivos: avaliar a eficiência do agente embólico líquido Onyx® em produzir oclusão completa dos aneurismas intracranianos de colo largo e avaliar a estabilidade do tratamento aos 6 meses e aos 18 meses, por meio de controles angiográficos. Casuística e métodos: Esta tese foi realizada na Seção de Neuroradiologia Intervencionista da Med Imagem, do Hospital São Joaquim da Real e Benemérita Associação Portuguesa de Beneficência de São Paulo, através da revisão de dados clínicos e radiológicos de 69 pacientes tratados pelo autor, com 84 aneurismas intracranianos de colo largo no período de julho de 2002 a fevereiro de 2006. Dez pacientes eram do sexo masculino e 59 do sexo feminino, com idade variando de 24 anos a 86 anos (mediana de 52 anos). Todos os aneurismas tinham origem lateral à artéria e apresentavam pelo menos um dos critérios usados para definir colo largo - colo maior que 4 mm de diâmetro e relação saco/colo menor que 1,5. Cinqüenta aneurismas eram pequenos, 30 grandes e quatro gigantes (diâmetro máximo menor que 12mm, de 12mm a 25mm e maiores que 25mm, respectivamente). As apresentações clínicas mais comuns foram: achado incidental em 34 pacientes, pós-hemorragia sub aracnóide e recanalização após tratamento com espirais destacáveis em 10. A maioria dos aneurismas era da artéria carótida interna (76 aneurismas). Controles angiográficos foram feitos ao final, aos seis meses e aos 18 meses do tratamento (controles I, II e III respectivamente), sendo analisados principalmente o grau de oclusão (completa ou incompleta), incidência de recanalização e complicações clínicas. Avaliação estatística foi feita pelo método de Kaplan-Meier para o percentual cumulativo de oclusão completa e percentual de recanalização e análise univariada e multivariada dos fatores preditivos de oclusão total imediata e tardia através de regressão logística. Resultados: O índice de oclusão completa foi de 65,5%, 84,6% e de 90,3% para todos os aneurismas, nos controles I, II e III respectivamente. Estes índices foram de 74%, 95,1% e de 95,2% para os aneurismas pequenos e de 53,3%, 70% e de 80% para os aneurismas grandes nos controles I, II e III respectivamente. Oclusão completa ocorreu em 50% dos aneurismas gigantes nos controles I e II, sem haver controle III neste grupo. Recanalização ocorreu em 3 aneurismas (4,6%). O porcentual cumulativo de oclusão completa foi de 97,63% (IC de 95% variando de 95,27 a 100) para os aneurismas pequenos aos 9 meses e de 83,86% (IC de 95% variando de 67,73 a 100) para os aneurismas grandes aos 21 meses. Três pacientes faleceram (4,3%), havendo relação com o procedimento em dois (2,9%). Morbidade permanente ocorreu em cinco pacientes (7,2%), sendo incapacitante em um (1,4%). Conclusões: 1. O uso do Onyx® foi eficiente na oclusão completa dos aneurismas intracranianos de colo largo. 2. O tratamento foi estável nos controles angiográficos aos 6 meses e aos 18 meses. / Introduction: The high rate of incomplete occlusion and intracranial large neck aneurysms recanalization lead to the development of new techniques, including the use of Onyx®. Purpose: to evaluate the efficacy of the liquid embolic system Onyx ® to produce completes occlusion of the intracranial large neck aneurysms and evaluates the stability of the treatment at 6 month and 18 month angiographic control. Materials and Methods: this thesis has been performed at Section of Interventional Neuroradiology of Med Imagem, at the Hospital São Joaquim da Real e Benemérita Associação Portuguesa de Beneficência de São Paulo, based on a review of clinical and radiological records of 69 patients treated by the author, harboring 84 large neck intracranial aneurysms between July 2002 and February 2006. Ten patients were male and 59 female, with age ranging from 24 to 86 years old. All aneurysms were lateral to the parent vessel and were wide neck (neck > 4 mm and/or domus to neck ratio < 1.5). Fifty aneurysms were small (<12 mm), 30 were large (12 to 25 mm) and 4 were giant (> 25 mm). Thirty four aneurysms were incidental, 10 were ruptured and 10 were recanalized after coil treatment and the majority was located in the internal carotid artery (76). Angiographic follow-up was done at the end of the procedure, at six month and at 18 month (controls I, II and III respectively), analyzing the rate of complete occlusion, recanalization and clinical complication. Statically analysis were done by Kaplan-Meier method for cumulative percentage of complete aneurysm occlusion and for recanalization, and univariate and multivariate analysis of predictive factors of immediate and late complete occlusion through logistic regression. Results: Complete aneurysm occlusion was achieved in 65.5% on immediate control, in 84.6% at 6 month, and in 90.3% at 18 month follow-up periods for all aneurysms. This rate was 74%, 95.1% and 95.2% for small and 53.3%, 70% and 80% for large aneurysms at the same follow-up periods. In the giant aneurysm group, two had complete and stable occlusion at six month follow-up angiography. Recanalization was seen in three aneurysms (4,6%). Kaplan Meyer\'s cumulative percentage of complete aneurysm occlusion was 97.63% (CI 95% ranging from 95,27 to 100) for small aneurysms at 9 months and 83.86% (CI 95% ranging from 67,73 to 100) for large aneurysms at 21 months. There were three deaths (4,3%), two procedure-related (2.9%). Overall morbidity was 7.2%, being disabling in one (1,4%). Conclusions: 1. The use of Onyx was efficient in the complete occlusion of wide neck intracranial aneurysms. 2. The treatment was stable at 6 month and 18 month angiographic controls.

During brain activity neurons release the major excitatory transmitter glutamate, which is taken up by astrocytes and converted to glutamine. Glutamine returns to neurons for re-conversion to glutamate. This glutamate-glutamine cycle is energy demanding. Glutamate turnover in injured brain was studied using an animal iron-induced posttraumatic epilepsy model and using neurointensive care data from 33 patients with spontaneous subarachnoid hemorrhage (SAH). Immunoblotting revealed that the functional form of the major astrocytic glutamate uptake protein GLT-1 was decreased 1-5 days following a cortical epileptogenic iron-injection, presumably due to oxidation-induced aggregation. Using microdialysis it was shown that the GLT-1 decrease was associated with increased interstitial glutamate levels and decreased interstitial glutamine levels. The results indicate a possible posttraumatic and post-stroke epileptogenic mechanism. Analysing 3600 microdialysis hours from patients it was found that the interstitial lactate/pyruvate (L/P) ratio correlate with the glutamine/glutamate ratio (r =-0.66). This correlation was as strong as the correlation between L/P and glutamate (r=0.68) and between lactate and glutamate (r=0.65). Pyruvate and glutamine correlated linearly (r=0.52). Energy failure periods, defined as L/P&gt;40, were associated with high interstitial glutamate levels. Glutamine increased or decreased during energy failure periods depending on pyruvate. Energy failure periods were clinically associated with delayed ischemic neurological deficits (DIND) or development of radiologically verified infarcts, confirming that L/P&gt;40 is a pathological microdialysis pattern that can predict ischemic deterioration after SAH. DIND-associated microdialysis patterns were L/P elevations and surges in interstitial glutamine. Glutamine and pyruvate correlated with the cerebral perfusion pressure (r=0.25, r=0.24). Glutamine and the glutamine/glutamate ratio correlated with the intracranial pressure (r=-0.29, r=0.40). Glutamine surges appeared upon substantial lowering of the intracranial pressure by increased cerebrospinal fluid drainage. Increased interstitial glutamine and pyruvate levels may reflect augmented astrocytic glycolysis in recovering brain tissue with increased energy demand due to a high glutamate-glutamine turnover.

Many patients with an aneurysmal subarachnoid haemorrhage (SAH) exhibit difficulties in rehabilitation, even in cases of a good prognosis. The present project investigates this using qualitative methods and standardised outcome measures. Patients with SAH treated at Uppsala University Hospital between 2002 and 2005 with an expected good prognosis were consecutively included. In addition, nurses working with such patients were interviewed. Outcome was assessed in terms of perception of care, psychiatric health, coping and health related quality of life (HRQoL). Qualitative content analyses revealed eight categories, which were divided into two patterns, Confident or Pessimistic perception of recovery, largely on the basis of the presence or absence of depression. Eighty-three patients were assessed by The Structured Clinical Interview for DSM-IV, Axis I (SCID-I). Forty-one percent fulfilled criteria for any psychiatric disorder seven months after SAH and 45 % presented with a history of lifetime psychiatric morbidity. Logistic regressions indicated that a psychiatric history was related to a higher risk of psychiatric problems seven months after SAH, as well as a lower return to work. SAH patients had lower HRQoL than the general Swedish population; almost entirely in the subgroup with a psychiatric history prior to the SAH. Those with a psychiatric history used more evasive, fatalistic, emotive and palliative coping strategies associated with inability to handle illness. Multiple regressions revealed that a psychiatric history and use of coping were independently associated with HRQoL, albeit more in the mental than the physical domains. Qualitative content analyses revealed that nurses viewed patients’ support needs as a process ranging from technological to emotional care. Shortcomings in the communication between nurses in acute and rehabilitation settings on the subject of support were acknowledged. The results underline the importance of early diagnosis of coexisting psychiatric illness and the need for an intact health care chain.

Patients admitted in similar clinical condition after spontaneous SAH can develop very different clinical courses. This could depend on the severity of the initial global ischemic brain injury at ictus. In the present study, we explored relations between clinical and radiological parameters at admission that indicate a more severe initial impact, and the following days hormone levels and brain metabolism. Early global cerebral oedema (GCE) on computed tomography occurred in 57 % of SAH patients and was associated with a more severe clinical condition. The brain’s glucose metabolism, measured with intracerebral microdialysis (MD), changed the first days. MD-glucose was initially high and MD-pyruvate low. MD-glucose gradually decreased and MD-pyruvate and MD-lactate increased, suggesting a transition to a hyperglycolytic state. This was more pronounced in patients with GCE. Similar patterns were seen for interstitial non-transmitter amino acids. From initial low concentrations, they gradually increased in parallel with MD-pyruvate. The amino acid concentrations were higher for patients admitted in better clinical condition. Insulin lowered MD-glucose and MD-pyruvate even when plasma glucose values remained high. P-ACTH and S-cortisol were elevated early after SAH. GCE was associated with higher S-cortisol acutely. Urine cortisol excretion, indicating levels of free cortisol, were higher in patients in a better clinical condition. Suppressed P-ACTH occurred in periods of brain ischemia. We suggest that GCE on the first CT scan is a warning sign indicating increased vulnerability if the patient is exposed to compromised energy supply or increased energy demand. Reduction of blood glucose after SAH should be done with caution. The temporal change of the glucose metabolism and the amino acid concentrations probably reflect activated repair mechanisms. This should be considered in the intensive care treatment of SAH patients. Finally, our results support earlier observations that the response of the hypothalamic-pituitary-adrenal system is important in critical care.

This study reports the investigation of hyperbaric opioids and 10% glucose studied in a experimental in vitro model of a subarachnoid space and the in vivo subarachnoid administration of hyperbaric opioids and 10% glucose in horses. The first in vitro phase was done with a translucid poly vinil chloride (PVC) model filled with horse cerebral spinal fluid and injected with hyperbaric opioids and 10% glucose tinted with methylene blue. The objective was to evaluate the physic behavior of the substances within the model. In the second in vivo phase, the hyperbaric opioids (morphine, methadone and buprenorphine) were subarachnoidally administered in six adult horses through a subarachnoid catheter. Cardiopulmonary effects, behavior and pain threshold to noxious electrical stimulation on the perineal, lumbar, sacral and thoracic dermatomes was evaluated. Theresults demonstrated that the model was able to indicate the more appropriate opioids to be used subarachnoidally, and that segmental analgesia was considered intense with hyperbaric morphine and hyperbaric methadone, and moderate with hyperbaric buprenorphine, with minimal effects on cardiorespiratory function, without ataxia or CNS excitation. / Este trabalho apresenta a investigação da utilização de soluções hiperbáricas de opióides e glicose a 10% em um modelo experimental in vitro do espaço subaracnóide, bem como o estudo in vivo da administração de opióides hiperbáricos e glicose a 10% pela via subaracnóide em cavalos. A primeira fase in vitro , constou da utilização de um modelo confeccionado em PVC (policloreto de vinila) transparente, preenchido com líquido cérebro espinhal eqüino, onde foram injetados os agentes opióides hiperbáricos e glicose a 10% marcados com azul de metileno, com o objetivo de avaliar o comportamento físico de distribuição das substâncias no modelo. Na segunda fase in vivo , os opióides hiperbáricos (morfina, buprenorfina e metadona) e glicose a 10% (grupo controle) foram administrados pela via subaracnóide em seis cavalos adultos por meio de um cateter. Avaliaram-se efeitos cardiorrespiratórios, comportamentais e limiar doloroso por estimulação elétrica dos dermátomos perineal, sacral, lombar e torácico. Os resultados mostraram que o modelo proposto serviu como base para a escolha dos agentes utilizados pela via subaracnóide. Houve produção de analgesia segmentar considerada intensa com a morfina hiperbárica e a metadona hiperbárica, e analgesia moderada com a buprenorfina hiperbárica, com mínimos efeitos sobre as funções cardiorrespiratórias, sem ocorrência de ataxia ou excitação do SNC.

Submitted by Isabela Leite Ferraz Cabral (isabelalferraz@hotmail.com) on 2018-04-19T13:07:04Z No. of bitstreams: 1 Isabela Leite Ferraz (após a defesa).pdf: 2321770 bytes, checksum: 6bfabab6d5e2449baea610ec9c7969ec (MD5) / Approved for entry into archive by Luciana Pizzani null (luciana@btu.unesp.br) on 2018-04-19T17:32:17Z (GMT) No. of bitstreams: 1 cabral_ilf_dr_bot.pdf: 2321770 bytes, checksum: 6bfabab6d5e2449baea610ec9c7969ec (MD5) / Made available in DSpace on 2018-04-19T17:32:17Z (GMT). No. of bitstreams: 1 cabral_ilf_dr_bot.pdf: 2321770 bytes, checksum: 6bfabab6d5e2449baea610ec9c7969ec (MD5) Previous issue date: 2018-02-21 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Justificativa e objetivo: o hábito de tatuar o corpo faz parte da cultura de muitos povos no mundo. A partir do início dos anos 1990, passou a ser utilizada por alguns grupos sociais e em faixa etária determinada como uma forma de arte no corpo. Os pigmentos podem conter componentes orgânicos e inorgânicos, metais e solventes. Há grande variação na composição química destes, o que dá origem às diferentes cores. Pouco se conhece sobre as possíveis implicações da introdução de uma agulha para realização de anestesia regional sobre uma pele tatuada. Alguns autores questionam se o pigmento contido na tatuagem pode desencadear aracnoidite química. Estudo experimental determinou infiltrado inflamatório linfoplasmacitário perivascular nas meninges de coelhos, 6 meses após punção subaracnoidea sobre pele tatuada. O objetivo desta pesquisa foi avaliar se a punção subaracnoidea realizada sobre a pele tatuada de coelhos ocasiona alterações histológicas precoces nas meninges. Material e Métodos: após a aprovação da Comissão de Ética e Pesquisa no Uso de Animais, foram utilizados 28 coelhos adultos jovens, da raça Grupo Genético de Botucatu, com pesos entre 3300 e 5400g e comprimento de medula espinal (espaço medido entre a base do crânio e o espaço lombossacral) entre 38 e 41 cm, fornecidos pelo Biotério da Faculdade de Medicina de Botucatu. Os animais foram divididos em 2 grupos (G): G1- punção subaracnoidea sobre tatuagem e injeção de solução salina a 0,9% e G2 - punção subaracnoidea sobre pele não tatuada e injeção de solução salina a 0,9%. Após anestesia venosa com xilazina e cetamina, os animais de G1 foram tatuados e, após 30 dias, sob a mesma anestesia, foi realizada a abordagem do espaço subaracnoideo, com agulha de Quincke 22G 21/2”, no espaço intervertebral entre a primeira e a segunda vértebra sacral, guiada por ultrassom. Os animais de G1 e G2 receberam as soluções correspondentes em volume de 5 μL por centímetro de medula espinal (aproximadamente 0,2 mL). Os animais foram avaliados clinicamente quanto à sensibilidade e à motricidade por 30 dias, após os quais foram sacrificados e retiradas as porções lombar e sacral da medula espinhal para exame histológico por microscopia óptica. Resultados: onze animais (78,6%) de G1 apresentaram lesões histológicas focais na pia-máter e aracnoide. Nos animais de G2 não foram encontradas alterações histológicas no tecido nervoso, nos vasos sanguíneos ou nas meninges. Conclusão: são precoces as alterações histológicas meníngeas desencadeadas pela introdução do pigmento da tatuagem após punção subaracnoidea. / Background: body tattooing is cultural for many people around the world. Since the early 1990s, it began to be used by some social groups and some age groups as a body art. The pigments may contain organic and inorganic components, metals and solvents. There is a great variation in the chemical composition of these pigments and that is why they produce different colors. We don’t know the possible implications of introducing a needle for performing regional anesthesia on a tattooed skin. Some authors question whether the pigment contained in the tattoo can trigger chemical arachnoiditis. One experimental study showed perivascular lymphoplasmacytic inflammatory infiltrate in rabbit meninges, 6 months after subarachnoid puncture on tattooed skin. The aim of this study was to evaluate if the subarachnoid puncture performed on the tattooed skin of rabbits already causes early histological changes in the meninges. Material and Methods: after Ethics Committee’s approval, it was used 28 young adult rabbits from Botucatu’s genetic group. The rabbits weights were between 3000 and 4500g and the length of spine (space measured from the base of the skull to lumbosacral space) were between 38 and 41 cm provided by the Medical Center of Botucatu Medical School. The animals were divided into 2 groups (G): in G1 group there was a subarachnoid puncture on tattooing and injection of 0.9% saline solution while in G2 group there was a subarachnoid puncture on non-tattooed skin and injection of 0.9% saline solution. After venous anesthesia with xylazine and ketamine, the G1 animals were tattooed. After 30 days, under the same anesthesia, the subarachnoid space were accessed, with Quincke's Needle 22G 21/2” , in the intervertebral space between the first and second sacral vertebra. All the procedure was ultrasound guided. The rabbits of G1 and G2 groups received the corresponding volume solutions of 5 μl per centimeter of spinal cord (approximately 0.2 mL). The animals were clinically assessed for sensitivity and motor function for 30 days. After that, they were sacrificed and the lumbar and sacral portions of the spinal cord were removed for histological examination by light microscopy. Results: eleven animals (78.6%) of G1 group had focal histological lesions in the pia mater and arachnoid. No histological changes were found in nervous tissue, blood vessels or meninges on G2 group. Conclusions: early meningeal histological changes are triggered by introduction of tattoo pigment into central nervous system after subarachnoid puncture. / FAPESP - Proc 2014/24053-9

Orientador: Eliana Marisa Ganem / Resumo: Justificativa e objetivo: o hábito de tatuar o corpo faz parte da cultura de muitos povos no mundo. A partir do início dos anos 1990, passou a ser utilizada por alguns grupos sociais e em faixa etária determinada como uma forma de arte no corpo. Os pigmentos podem conter componentes orgânicos e inorgânicos, metais e solventes. Há grande variação na composição química destes, o que dá origem às diferentes cores. Pouco se conhece sobre as possíveis implicações da introdução de uma agulha para realização de anestesia regional sobre uma pele tatuada. Alguns autores questionam se o pigmento contido na tatuagem pode desencadear aracnoidite química. Estudo experimental determinou infiltrado inflamatório linfoplasmacitário perivascular nas meninges de coelhos, 6 meses após punção subaracnoidea sobre pele tatuada. O objetivo desta pesquisa foi avaliar se a punção subaracnoidea realizada sobre a pele tatuada de coelhos ocasiona alterações histológicas precoces nas meninges. Material e Métodos: após a aprovação da Comissão de Ética e Pesquisa no Uso de Animais, foram utilizados 28 coelhos adultos jovens, da raça Grupo Genético de Botucatu, com pesos entre 3300 e 5400g e comprimento de medula espinal (espaço medido entre a base do crânio e o espaço lombossacral) entre 38 e 41 cm, fornecidos pelo Biotério da Faculdade de Medicina de Botucatu. Os animais foram divididos em 2 grupos (G): G1- punção subaracnoidea sobre tatuagem e injeção de solução salina a 0,9% e G2 - punção subaracnoidea s... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Background: body tattooing is cultural for many people around the world. Since the early 1990s, it began to be used by some social groups and some age groups as a body art. The pigments may contain organic and inorganic components, metals and solvents. There is a great variation in the chemical composition of these pigments and that is why they produce different colors. We don’t know the possible implications of introducing a needle for performing regional anesthesia on a tattooed skin. Some authors question whether the pigment contained in the tattoo can trigger chemical arachnoiditis. One experimental study showed perivascular lymphoplasmacytic inflammatory infiltrate in rabbit meninges, 6 months after subarachnoid puncture on tattooed skin. The aim of this study was to evaluate if the subarachnoid puncture performed on the tattooed skin of rabbits already causes early histological changes in the meninges. Material and Methods: after Ethics Committee’s approval, it was used 28 young adult rabbits from Botucatu’s genetic group. The rabbits weights were between 3000 and 4500g and the length of spine (space measured from the base of the skull to lumbosacral space) were between 38 and 41 cm provided by the Medical Center of Botucatu Medical School. The animals were divided into 2 groups (G): in G1 group there was a subarachnoid puncture on tattooing and injection of 0.9% saline solution while in G2 group there was a subarachnoid puncture on non-tattooed skin and injection of 0.... (Complete abstract click electronic access below) / Doutor