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Pneumoperitoneum caused by gastroscopy in a jaundiced patient treated endoscopically after initial percutaneous approach.
No full textNo abstract availabl
Chievitz' juxtaparotid organ, free from cancer
No full textAbstractin English, Italian INTRODUZIONE: Fino alla metà del XX secolo, l’organo di Chievitz è stato considerato un organo embrionale, che scompare con la crescita. Zenker, invece, nel 1953, ha dimostrato l’esistenza di questo organo anche nella vita adulta. STUDIO: In questo articolo descriviamo l’embriologia, l’anatomia macroscopica e microscopica, l’ultrastruttura, il significato funzionale e la patologia dell’organo iuxtaparotideo di Chievitz’(CJO). Il CJO non è un organo macroscopicamente evidente, ma ha l’aspetto simile ad un nervo. Il CJO prende collegamenti con il muscolo buccinatore, a livello del condotto parotideo e con il muscolo pterigoideo mediale. Il parenchima cellulare è avvolto da tessuto connettivo, che è diviso in tre strati: lo strato interno - “strato fibrosum internum” -, composto da microfibrille di collagene; lo strato intermedio - “stratum nervosum” - contenente un nucleo interno lamellare e strutture nervose di Ruffini; lo strato esterno - “stratum fibrosum externum”, che è una capsula di collagene. Le cellule parenchimali contengono enzimi, quali la fosfatasi alcalina e l’anidrasi carbonica, con una ricca attività enzimatica, simile a quella delle cellule duttali delle ghiandole salivari. Il CJO presenta, inoltre, un’importante funzione meccanosensore di questa regione. Quando viene eseguita una resezione chirurgica per un carcinoma orale, il CJO può essere presente nel pezzo operatorio. Il CJO può essere erroneamente diagnosticato come invasione perineurale da carcinoma. CONCLUSIONE: Sulla base della revisione della Letteratura, tuttavia, si può definire che l’organo di Chievitz è l’unico organo in cui il cancro non si verificaAbstractin English, Italian INTRODUCTION: Up to the half of twentieth century, Chievitz organ was considered an embryonal organ, disappearing with growth. But Zenker, in 1953, demonstrated the existence of this organ in adult life, too4. REVIEW: In this article we review the embryology, the macroscopic and microscopic anatomy, the ultrastructure, the functional significance and the pathology of the Chievitz'Juxtaparotid Organ (CJO). The CJO is not a macroscopic apparent organ, but it looks like a nerve. The CJO takes connections with buccinator muscle, at the level of the parotid duct, and the medial pterygoid muscle. The cell parenchyma is enveloped by the connective tissue, that is divided into three layers15, 16: the inner layer -"stratum fibrosum internum"-, composed of collagenous and elastic microfibrils; the middle layer - "stratum nervosum" - containing a lamellar inner core and Ruffini SNF5; the external layer - "stratum fibrosum externum", that is a collagen capsule. The parenchymal cells show a rich enzyme activity. The parenchymal cells may play the same role as glomus cells of the 1st type and Merkel cells20, 21. When a surgical resection is performed for an oral carcinoma, the CJO may be present in the specimen25. The CJO may be wrongly diagnosed as perineural invasion by carcinoma26, 27, 28. CONCLUSION: We report that Chievitz' organ is the only organ in which the cancer does not occur
Laser Interstitial Thermotherapy for pancreatic tumor ablation: theoretical model and experimental validation
No full textEndoluminal Nd:YAG laser application in ex vivo biliary porcine tissue
No full textAdequate biliary drainage with endoscopic or percutaneous placement of self-expandable metal stents represents the goal of palliation in patients with inoperable malignant obstruction of the biliary tree. As an adjunct to stenting, various tissue ablation treatments have been proposed with conflicting results. The aim of this study was to test the effect on biliary tissue of a new ablation technique based on Nd:YAG laser light delivery. The study was conducted on ex vivo specimens of 18 healthy farm pigs, using cystic ducts that are the simplest biliary structures to isolate and cannulate ex vivo. A 22G cannula was positioned into the cystic duct and a quartz optical fibre, with a prototypal cooling system, was inserted into the cannula. Nd:YAG laser output powers of 10, 12, and 15 W were tested, with a total delivered energy of 1000 J in continuous mode in each case. After laser treatment, histological analysis was performed. At macroscopical examination, no lesions of the external wall of the cystic ducts were detected. At histopathological examination, a coagulative necrosis involving the entire mucosa up to the muscolaris propria without significant changes of periductal tissues was observed in all specimens. This study shows the possibility of using Nd:YAG laser on ex vivo porcine biliary ducts with the effect of obtaining a coagulative necrosis involving the whole mucosa
Theoretical assessment of principal factors influencing laser interstitial thermotherapy outcomes on pancreas
No full textEstimation of optical properties of neuroendocrine pancreas tumor with double-integrating-sphere system and inverse Monte Carlo model
No full textThe investigation of laser-tissue interaction is crucial for diagnostics and therapeutics. In particular, the estimation of tissue optical properties allows developing predictive models for defining organ-specific treatment planning tool. With regard to laser ablation (LA), optical properties are among the main responsible for the therapy efficacy, as they globally affect the heating process of the tissue, due to its capability to absorb and scatter laser energy. The recent introduction of LA for pancreatic tumor treatment in clinical studies has fostered the need to assess the laser-pancreas interaction and hence to find its optical properties in the wavelength of interest. This work aims at estimating optical properties (i.e., absorption, μ a , scattering, μ s , anisotropy, g, coefficients) of neuroendocrine pancreas tumor at 1064 nm. Experiments were performed using two popular sample storage methods; the optical properties of frozen and paraffin-embedded neuroendocrine tumor of the pancreas are estimated by employing a double-integrating-sphere system and inverse Monte Carlo algorithm. Results show that paraffin-embedded tissue is characterized by absorption and scattering coefficients significantly higher than frozen samples (μ a of 56 cm−1 vs 0.9 cm−1, μ s of 539 cm−1 vs 130 cm−1, respectively). Simulations show that such different optical features strongly influence the pancreas temperature distribution during LA. This result may affect the prediction of therapeutic outcome. Therefore, the choice of the appropriate preparation technique of samples for optical property estimation is crucial for the performances of the mathematical models which predict LA thermal outcome on the tissue and lead the selection of optimal LA settings
TEMPERATURE DISTRIBUTION MONITORING DURING ND: YAG LASER ABLATION OF PORCINE PANCREATIC TISSUE
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