Scar neuromas as triggers for headache after craniotomy: clinical evidence

We present four cases of headache with variable intensity, located in close proximity to a craniotomy incision which was performed for non-traumatic reasons. Since manual palpation of the scar often triggers pain, and infiltration with local anesthetics reduce or abolish the pain in some patients, we suggest that neuromas or nerve entrapment in the scars, as a result of the surgery, are responsible for headaches. Although local infiltrations or nerve blocks are often used for diagnostic reasons, herein we consider that they are also of therapeutic value. We review the current known pathophysiology of post-craniotomy headaches and present a hypothesis suggesting a greater recognition of the potential contribution of neuroma formation in areas of scars tissue to contribute to this kind of headache.

Percutaneous sciatic nerve block with tramadol induces analgesia and motor blockade in two animal pain models

Local anesthetic efficacy of tramadol has been reported following intradermal application. Our aim was to investigate the effect of perineural tramadol as the sole analgesic in two pain models. Male Wistar rats (280-380 g; N = 5/group) were used in these experiments. A neurostimulation-guided sciatic nerve block was performed and 2% lidocaine or tramadol (1.25 and 5 mg) was perineurally injected in two different animal pain models. In the flinching behavior test, the number of flinches was evaluated and in the plantar incision model, mechanical and heat thresholds were measured. Motor effects of lidocaine and tramadol were quantified and a motor block score elaborated. Tramadol, 1.25 mg, completely blocked the first and reduced the second phase of the flinching behavior test. In the plantar incision model, tramadol (1.25 mg) increased both paw withdrawal latency in response to radiant heat (8.3 +/- 1.1, 12.7 +/- 1.8, 8.4 +/- 0.8, and 11.1 +/- 3.3 s) and mechanical threshold in response to von Frey filaments (459 +/- 82.8, 447.5 +/- 91.7, 320.1 +/- 120, 126.43 +/- 92.8 mN) at 5, 15, 30, and 60 min, respectively. Sham block or contralateral sciatic nerve block did not differ from perineural saline injection throughout the study in either model. The effect of tramadol was not antagonized by intraperitoneal naloxone. High dose tramadol (5 mg) blocked motor function as well as 2% lidocaine. In conclusion, tramadol blocks nociception and motor function in vivo similar to local anesthetics.

Pachymetry-Guided Intrastromal Air Injection ("Pachy-Bubble") for Deep Anterior Lamellar Keratoplasty

To evaluate an innovative technique for intrastromal air injection to achieve deep anterior lamellar keratoplasty (DALK) with bare Descemet membrane (DM). Thirty-four eyes with anterior corneal pathology, including 27 with keratoconus, underwent DALK. After 400 mm trephination with a suction trephine, ultrasound pachymetry was performed 0.8 mm internally from the trephination groove in the 11 to 1 o'clock position. In this area, a 2-mm incision was created, parallel to the groove, with a micrometer diamond knife calibrated to 90% depth of the thinnest measurement. A cannula was inserted through the incision and 0.5 mL of air was injected to dissect the DM from the stroma. After peripheral paracentesis, anterior keratectomy was carried out to bare the DM. A 0.25-mm oversized graft was sutured in place. Overall, 94.1% of eyes achieved DALK. Bare DM was achieved in 30 eyes, and a pre-DM dissection was performed in 2 eyes. Air injection was successful in detaching the DM (achieving the big bubble) in 88.2% of the eyes. In keratoconus eyes, the rate was 88.9%. All cases but one required a single air injection to achieve DM detachment. Microperforations occurred in 5 cases: 3 during manual layer-by-layer dissection after air injection failed to detach the DM, 1 during removal of the residual stroma after big-bubble formation, and 1 during the diamond knife incision. Two cases (5.9%) were converted to penetrating keratoplasty because of macroperforations. The technique was reproducible, safe, and highly effective in promoting DALK with bare DM.

Análise microscópica de incisões realizadas com três diferentes pontas do laser Erbio YAG

The study analised microscopic wound healing of incision made with Er:YAg laser with three different tips. In six Rattus norvegicus, incision was made with Laser Er-YAG (KeyLaser) using tips 2051, 2055 and 2056. The animals were killed at 7 e 14 and the sites of incision are photographed in this time. The parts containing the incision area were prepared for microscopic analysis, performing sections of 7µm and staining with haematoxylin and eosin. Zone of tissue ablation, zone of thermal necrosis, the presence and character of inflammatory cell infiltrate and wound healing were measured. The 2051 tip produced faster and defined edges of the wound. To create wound 1.30 mm in depth lasers tips required at last five passes within the same line of incision. Microscopic analysis shows no difference with use of three different laser tips

Evolución geomorfológica del Macizo Hespérico peninsular:estudio de un sector comprendido entre las provincias de Lugo y Ourense (Galicia, NW de España)

[EN] This paper deals with the relief generation in Ourense, an interior territory of the Galicia Country, at NW Spain, after the breakdown of Pangea 200 million years ago. The rupture of supercontinent causes the main effects in the outer part of Galicia, the present coast line and the shelf, but also the inner parts of Galicia where the landscape changes dramatically mainly ruled by fluvial incision connected with uprising, (orogenic, epirogenic, or isostatic origin), or even with eustatic oscillations, that shaped the previous old mesozoic landscape. Various things complicate the correct understanding of Galician geomorphology:1) the prevalent hercynian structure, (presumably reactivated during the Alpine Orogeny), causes that the epigenic processes, (fluvial, glaciar, marine and etching), acting on Galicia from Mesozoic to present times, produce end forms identified erroneously at the previous literature as tectonic and not as etch forms profiting from lithological or structural contrasts. 2) the common morphotectonic model accepted by all previous researchers establishes for the whole of Galicia a blocky pattern, (horst and graben like), due to extensional tectonic regime. This model is proved as no longer valid because the Galician tertiary basins, even were described at the past as graben depressions never have this origin. 3) big differences exist between the north and western sides of Galicia that show contrasted tectonic regime: compressional (with forms as the so called raised platforms), at the northern coast border, and extensional (with forms so typical as the Rias), at the western side. The study area is located at the confluence of two tectonic domains where the above mentioned effects are coincidents and specially well showed through different effects: prominent assimetry of fluvial captures (west facing), pronounced river incision and different kinds of tertiary basins: either strike slipe faults (Maceda, Xinzo de Limia, etc), or overslipped by inverse faults, (Quiroga, A Rúa, etc.), or even corresponding with depressions never, (or anywise passively), affected by tectonic movements, (Monforte). The paper include a detailed inventory of surfaces and terrace levels and their incision sequence which allow stablish a relative chronology of geomorphic evolution at this area of NW Spain during meso-cainozoic times.

Las terrazas del rio Miño en el tramo Chantada-As Neves (límite de Galicia Portugal)

[ES] La cartografía geomorfológica es especialmente difícil en áreas con depósitos escasos, poco significativos y de cronología incierta,con formas multiedad y multiorigen. Tal es el caso de Galicia. Este trabajo es un intento de reconstruir la historia geomorfológica de Galicia durante el Cenozoico en un área especialmente relevante por su situación geodinámica. Se ha hecho un inventario exhaustivo de los niveles de terrazas erosivas y de acumulación en un tramo específico, por sus características morfológicas del curso principal del río Miño. Se presentan aquí los sistemas de terrazas entre Chantada y As Neves y se relacionan con las tres superficies de corrosión química (etched surfaces) más relevantes en la zona: R800, R600 y R400. Se analiza también su relación con el perfil longitudinal del río. Utilizando los únicos criterios existentes (continuidad topográfica y altitud), se propone para el sector estudiado un modelo evolutivo esencialmente determinado por la incisión fluvial asociada a la colisión entre la Placa Euroasiática y la Ibérica durante el Paleógeno y que geomorfológicamente se inicia a partir de la formación del aplanamiento R600, equivalente en Galicia a la Superficie Fundamental Peninsular.

Las terrazas del río Sil en el tramo Carucedo-Os Peares, SE de Galicia

[ES] Se describen los sistemas de terrazas del Río Sil desde el Bierzo hasta la confluencia con el Miño. En este tramo el río se encaja profundamente sobre las principales superficies de erosión del SE gallego (R400, R600, R800, RlOOO y R1200). Junto a los niveles de terraza con depósitos se observa la presencia de superficies terraza y aplanamientos de mayor extensión, siempre asociados al encajamiento fluvial. Se analiza la morfometría y los perfiles longitudinales de la red; así como la distribución de las terrazas y aplanamientos incluidos en el encajamiento. Se reconocen algunos cambios en la evolución de la red simultáneos a la sedimentación de las fosas terciarias (Monforte de Lemos, Quiroga, A Rúa-O Barco). La antigüedad de la red y un descenso generalizado en el nivel de base del Sistema Miño-Sil, podría justificar estos acontecimientos. Sin embargo, existen indicios de cierto control tectónico. Por último se propone un modelo evolutivo del tramo estudiado, para la etapa posterior a la formación del aplanamiento RlOOO.

Erosione e sollevamento nell'arco calabro-peloritano

The Calabrian-Peloritani arc represents key site to unravel evolution of surface processes on top of subducting lithosphere. During the Pleistocene, in fact the arc uplifted at rate of the order of about 1mm/yr, forming high-standing low-relief upland (figure 2). Our study is focused on the relationship between tectonic and land evolution in the Sila Massif, Messina strait and Peloritani Mts. Landforms reflect a competition between tectonic, climatic, and surficial processes. Many landscape evolution models that explore feedbacks between these competing processes, given steady forcing, predict a state of erosional equilibrium, where the rates of river incision and hillslope erosion balance rock uplift. It has been suggested that this may be the final constructive stage of orogenic systems. Assumptions of steady erosion and incision are used in the interpretation of exhumation and uplift rates from different geologic data, and in the formulation of fluvial incision and hillslope evolution models. In the Sila massif we carried out cosmogenic isotopes analysis on 24 samples of modern fluvial sediments to constrain long-term (~103 yr) erosion rate averaged on the catchment area. 35 longitudinal rivers profiles have been analyzed to study the tectonic signal on the landscape evolution. The rivers analyzed exhibit a wide variety of profile forms, diverging from equilibrium state form. Generally the river profiles show at least 2 and often 3 distinct concave-up knickpoint-bounded segments, characterized by different value of concavity and steepness indices. River profiles suggest three main stages of incision. The values of ks and θ in the lower segments evidence a decrease in river incision, due probably to increasing uplift rate. The cosmogenic erosion rates pointed out that old landscape upland is eroding slowly at ~0.1 mm/yr. In the contrary, the flanks of the massif is eroding faster with value from 0.4 to 0.5 mm/yr due to river incision and hillslope processes. Cosmogenic erosion rates mach linearly with steepness indices and with average hillslope gradient. In the Messina area the long term erosion rate from low-T thermochronometry are of the same order than millennium scale cosmogenic erosion rate (1-2 mm/yr). In this part of the chain the fast erosion is active since several million years, probably controlled by extensional tectonic regime. In the Peloritani Mts apatite fission-track and (U-Th)/He thermochronometry are applied to constraint the thermal history of the basement rock. Apatite fission-track ages range between 29.0±5.5 and 5.5±0.9 Ma while apatite (U-Th)/He ages vary from 19.4 to 1.0 Ma. Most of the AFT ages are younger than the overlying terrigenous sequence that in turn postdates the main orogenic phase. Through the coupling of the thermal modelling with the stratigraphic record, a Middle Miocene thermal event due to tectonic burial is unravel. This event affected a inner-intermediate portion of the Peloritani belt confined by young AFT data (<15 Ma) distribution. We interpret this thermal event as due to an out-of–sequence thrusting occurring in the inner portion of the belt. Young (U-Th)/He ages (c. 5 Ma) record a final exhumation stage with increasing rates of denudation since the Pliocene times due to postorogenic extensional tectonics and regional uplift. In the final chapter we change the spatial scale to insert digital topography analysis and field data within a geodynamic model that can explain surface evidence produced by subduction process.

Tectonic geomorphology and active strain of the Northern Apennines mountain front

The Northern Apennines (NA) chain is the expression of the active plate margin between Europe and Adria. Given the low convergence rates and the moderate seismic activity, ambiguities still occur in defining a seismotectonic framework and many different scenarios have been proposed for the mountain front evolution. Differently from older models that indicate the mountain front as an active thrust at the surface, a recently proposed scenario describes the latter as the frontal limb of a long-wavelength fold (> 150 km) formed by a thrust fault tipped around 17 km at depth, and considered as the active subduction boundary. East of Bologna, this frontal limb is remarkably very straight and its surface is riddled with small, but pervasive high- angle normal faults. However, west of Bologna, some recesses are visible along strike of the mountain front: these perturbations seem due to the presence of shorter wavelength (15 to 25 km along strike) structures showing both NE and NW-vergence. The Pleistocene activity of these structures was already suggested, but not quantitative reconstructions are available in literature. This research investigates the tectonic geomorphology of the NA mountain front with the specific aim to quantify active deformations and infer possible deep causes of both short- and long-wavelength structures. This study documents the presence of a network of active extensional faults, in the foothills south and east of Bologna. For these structures, the strain rate has been measured to find a constant throw-to-length relationship and the slip rates have been compared with measured rates of erosion. Fluvial geomorphology and quantitative analysis of the topography document in detail the active tectonics of two growing domal structures (Castelvetro - Vignola foothills and the Ghiardo plateau) embedded in the mountain front west of Bologna. Here, tilting and river incision rates (interpreted as that long-term uplift rates) have been measured respectively at the mountain front and in the Enza and Panaro valleys, using a well defined stratigraphy of Pleistocene to Holocene river terraces and alluvial fan deposits as growth strata, and seismic reflection profiles relationships. The geometry and uplift rates of the anticlines constrain a simple trishear fault propagation folding model that inverts for blind thrust ramp depth, dip, and slip. Topographic swath profiles and the steepness index of river longitudinal profiles that traverse the anti- clines are consistent with stratigraphy, structures, aquifer geometry, and seismic reflection profiles. Available focal mechanisms of earthquakes with magnitude between Mw 4.1 to 5.4, obtained from a dataset of the instrumental seismicity for the last 30 years, evidence a clear vertical separation at around 15 km between shallow extensional and deeper compressional hypocenters along the mountain front and adjacent foothills. In summary, the studied anticlines appear to grow at rates slower than the growing rate of the longer- wavelength structure that defines the mountain front of the NA. The domal structures show evidences of NW-verging deformation and reactivations of older (late Neogene) thrusts. The reconstructed river incision rates together with rates coming from several other rivers along a 250 km wide stretch of the NA mountain front and recently available in the literature, all indicate a general increase from Middle to Late Pleistocene. This suggests focusing of deformation along a deep structure, as confirmed by the deep compressional seismicity. The maximum rate is however not constant along the mountain front, but varies from 0.2 mm/yr in the west to more than 2.2 mm/yr in the eastern sector, suggesting a similar (eastward-increasing) trend of the apenninic subduction.

High-Speed Laser Processing of Thin Single and Multi-Layer Films

Theoretical models are developed for the continuous-wave and pulsed laser incision and cut of thin single and multi-layer films. A one-dimensional steady-state model establishes the theoretical foundations of the problem by combining a power-balance integral with heat flow in the direction of laser motion. In this approach, classical modelling methods for laser processing are extended by introducing multi-layer optical absorption and thermal properties. The calculation domain is consequently divided in correspondence with the progressive removal of individual layers. A second, time-domain numerical model for the short-pulse laser ablation of metals accounts for changes in optical and thermal properties during a single laser pulse. With sufficient fluence, the target surface is heated towards its critical temperature and homogeneous boiling or "phase explosion" takes place. Improvements are seen over previous works with the more accurate calculation of optical absorption and shielding of the incident beam by the ablation products. A third, general time-domain numerical laser processing model combines ablation depth and energy absorption data from the short-pulse model with two-dimensional heat flow in an arbitrary multi-layer structure. Layer removal is the result of both progressive short-pulse ablation and classical vaporisation due to long-term heating of the sample. At low velocity, pulsed laser exposure of multi-layer films comprising aluminium-plastic and aluminium-paper are found to be characterised by short-pulse ablation of the metallic layer and vaporisation or degradation of the others due to thermal conduction from the former. At high velocity, all layers of the two films are ultimately removed by vaporisation or degradation as the average beam power is increased to achieve a complete cut. The transition velocity between the two characteristic removal types is shown to be a function of the pulse repetition rate. An experimental investigation validates the simulation results and provides new laser processing data for some typical packaging materials.

Nuove tecniche per il trattamento della malattia paranale di Crohn

Studio prospettico su 75 pazienti con malattia paranale di Crohn che ha come obiettivo quello di confrontare i risultati tra le nuove terapie medico-chirurgiche emergenti. La prima procedura è comune a tutti i pazienti e consiste in un intervento di incisione degli ascessi, fistulectomia e posizionamento di setoni di drenaggio nei tramiti fistolosi per il controllo della sepsi.Successivamente i pazienti vengono divisi in cinque gruppi e sottoposti ai trattamenti per la chiusura dei tramiti fistolosi: terapia sistemica con Infliximab,terapia sistemica con Adalimumab,confezionamento di Flap endoanale, instillazione di colla di fibrina o posizionamento di protesi biologiche. Abbiamo osservato una chiusura completa dei tramiti fistolosi nel 60% dei pazienti trattati con Infliximab, 53% di quelli trattati con Adalimumab, 40% di quelli in terapia con colla di fibrina, 80% di quelli sottoposti a Flap endoanale e 60% di quelli trattati con protesi biologiche. Gli ottimi risultati raggiunti in con le diverse metodiche di trattamento chirurgico locale rappresentano una valida alternativa alla terapia con farmaci biologici. Tali nuove metodiche risultano anzi fondamentali per il trattamento di quei pazienti che dopo una terapia con farmaci biologici non hanno raggiunto una completa risoluzione del quadro (rescue therapy). Terapia biologica e nuove tecniche chirurgiche risultano pertanto complementari, la prima contribuendo al miglioramento della qualità della mucosa del canale anale e del retto basso sulla quale risulta quindi più agevole agire con le seconde con una percentuale di successo sempre maggiore.

[Surgical therapy of gynecomastia]

Nowadays surgical intervention is an essential part of the treatment of idiopathic gynecomastia. Choosing the right method is crucial and is based on the current status in the clinical and histological evaluation. Before finalizing the process of choosing a specific method a prior interdisciplinary evaluation of the patient is necessary to ascertain clear indications for a surgical intervention. Liposuction is one of the methods which have become popular in recent years. The advantages are the possible combination with traditional techniques, such as subcutaneous mastectomy or periareolar mastopexy. The main indication is for gynecomastia stage IIa/b and is justifiable due to the reduction in surgical complications and scarring. Furthermore this technique provides an excellent aesthetical outcome for the patient. A total of 162 patients suffering from gynecomastia stages I-III (according to Simon) were surgically treated between 2000 and 2010 and these cases were retrospectively evaluated. The results showed a decline in the use of a T-shaped incision in combination with subcutaneous mastectomy with periareolar tightening compared to an increase in the use of subcutaneous mastectomy in combination with liposuction. The excised tissue should always be sent for histological examination to make sure no malignant cells were present.

Hydrogels for nucleus replacement—Facing the biomechanical challenge

Hydrogels are considered promising for disc regeneration strategies. However, it is currently unknown whether the destruction of the natural interface between nucleus and surrounding structures caused by nucleotomy and an inadequate annulus closure diminishes the mechanical competence of the disc. This in vitro study aimed to clarify these mechanisms and to evaluate whether hydrogels are able to restore the biomechanical behaviour of the disc. Nucleus pressure in an ovine intervertebral disc was measured in vivo during day and night and adapted to an in vitro axial compressive diurnal (15min) and night (30min) load. Effects of different defects on disc height and nucleus pressure were subsequently measured in vitro using 30 ovine motion segments. Following cases were considered: intact; annulus incision repaired by suture and glue; annulus incision with removal and re-implantation of nucleus tissue; and two different hydrogels repaired by suture and glue. The intradiscal pressure in vivo was 0.75MPa during day and 0.5MPa during night corresponding to an in vitro axial compressive force of 130 and 58N, respectively. The compression test showed that neither the implantation of hydrogels nor the re-implantation of the natural nucleus, assumed as being the ideal implant, was able to restore the mechanical functionality of an intact disc. Results indicate the importance of the natural anchorage of the nucleus with its surrounding structures and the relevance of an appropriate annulus closure. Therefore, hydrogels that are able to mimic the mechanical behaviour of the native nucleus may fail in restoring the mechanical behaviour of the disc.

Antinociceptive activity of pre- versus post-operative intra-articular bupivacaine in goats undergoing stifle arthrotomy

OBJECTIVE: To evaluate the peri-operative analgesic efficacy of intra-articular bupivacaine administered before or after stifle arthrotomy. STUDY DESIGN: Prospective, randomized, blind, placebo-controlled experimental trial. ANIMALS: Thirty-nine healthy goats. METHODS: The goats were allocated randomly to one of three intra-articular treatment groups: group PRE (bupivacaine before and saline after surgery), group POST (saline before and bupivacaine after surgery) and group CON (saline before and after surgery). Anaesthesia was maintained with a constant end-tidal sevoflurane of 2.5%. Intra-operatively heart rate (HR), respiratory rate and mean arterial blood pressure (MAP) after critical surgical events (CSE) were recorded and compared with pre-incision values. Propofol requirements to maintain surgical anaesthesia were recorded. Flunixin was administered for 5 days. Post-operative pain assessment at 20 minutes, 2 hours, 4 hours after recovery and on day 2 and 3 included a multidimensional pain score (MPS), a lameness score and mechanical nociceptive threshold (MNT) testing. Rescue analgesia consisted of systemic opioids. Data were analysed using Kruskal-Wallis, Mann-Whitney, Friedman or chi-square tests as appropriate. RESULTS: Intra-operatively, group PRE had lower HR and MAP at several CSEs than groups POST/CON and required less propofol [0 mg kg(-1) (0-0 mg kg(-1))] than group POST/CON [0.3 mg kg(-1) (0-0.6 mg kg(-1))]. Post-operatively, group POST had significantly higher peri-articular MNTs than groups PRE and CON up to 4 hours after recovery. No treatment effect was detected for MPS, lameness scores and rescue analgesic consumption at any time point. CONCLUSIONS AND CLINICAL RELEVANCE: Pre-operative intra-articular bupivacaine provided notable intra-operative analgesia in goats undergoing stifle arthrotomy but did not reduce post-operative pain. Post-operative intra-articular bupivacaine provided a short lasting reduction of peri-articular hyperalgesia without affecting the requirements for systemic analgesia. Multimodal perioperative pain therapy is recommended to provide adequate analgesia for stifle arthrotomy in goats.

Interaction Between Nitrous Oxide, Sevoflurane, and Opioids: A Response Surface Approach

BACKGROUND:: The interaction of sevoflurane and opioids can be described by response surface modeling using the hierarchical model. We expanded this for combined administration of sevoflurane, opioids, and 66 vol.% nitrous oxide (N2O), using historical data on the motor and hemodynamic responsiveness to incision, the minimal alveolar concentration, and minimal alveolar concentration to block autonomic reflexes to nociceptive stimuli, respectively. METHODS:: Four potential actions of 66 vol.% N2O were postulated: (1) N2O is equivalent to A ng/ml of fentanyl (additive); (2) N2O reduces C50 of fentanyl by factor B; (3) N2O is equivalent to X vol.% of sevoflurane (additive); (4) N2O reduces C50 of sevoflurane by factor Y. These four actions, and all combinations, were fitted on the data using NONMEM (version VI, Icon Development Solutions, Ellicott City, MD), assuming identical interaction parameters (A, B, X, Y) for movement and sympathetic responses. RESULTS:: Sixty-six volume percentage nitrous oxide evokes an additive effect corresponding to 0.27 ng/ml fentanyl (A) with an additive effect corresponding to 0.54 vol.% sevoflurane (X). Parameters B and Y did not improve the fit. CONCLUSION:: The effect of nitrous oxide can be incorporated into the hierarchical interaction model with a simple extension. The model can be used to predict the probability of movement and sympathetic responses during sevoflurane anesthesia taking into account interactions with opioids and 66 vol.% N2O.