Gradual Thinning Research Articles

Long term follow-up of a family with GUCY2D dominant cone dystrophy.

To describe long term follow-up in a family with GUCY2D dominant cone dystrophy. Optical coherence tomography scans and fundus autofluorescence images were obtained. Flash and pattern electroretinograms (ERGs) and occipital pattern reversal visual evoked potentials were recorded. Two members of the same family (father and son) were identified to have the heterozygous R838C mutation in the GUCY2D gene. The father presented at the age of 45 with bilateral bull's eye maculopathy and temporal disc pallor. Over 13y of serial follow up visits, the bull's eye maculopathy progressed gradually into macular atrophy. Electrophysiological tests were significantly degraded suggesting poor macular function. Spectral-domain optical coherence tomography (SD-OCT) scans showed progressive loss and disruption of the ellipsoid layer at the foveal level. His son presented at the age of 16 with bilateral granular retinal pigment epithelial changes in both maculae. Electrophysiological testing was initially borderline normal but has gradually deteriorated to show reduced cone ERGs and macula function. SD-OCT demonstrated gradual macular thinning and atrophy bilaterally. Unlike his father, there was no disruption of the ellipsoid layer. Both family members exhibited gradual changes in their fundi, electrophysiological testing and multimodal imaging. Changes were milder than those observed in other mutations of the same gene.

Fluctuation Dynamo in a Collisionless, Weakly Magnetized Plasma

Abstract Results from a numerical study of fluctuation dynamo in a collisionless, weakly magnetized plasma are presented. The key difference between this dynamo and its magnetohydrodynamic (MHD) counterpart is the adiabatic production of magnetic-field-aligned pressure anisotropy by the amplification of a weak seed field. This, in turn, drives kinetic instabilities on the ion-Larmor scale—namely, firehose and mirror—which sever the adiabatic link between the thermal and magnetic pressures, thereby allowing the dynamo to proceed. After an initial phase of rapid growth driven by these instabilities, the magnetic energy grows exponentially and exhibits a spectrum that peaks near the resistive scale, similar to the large-magnetic-Prandtl-number ( ) MHD dynamo. The magnetic field self-organizes into a folded-sheet topology, with direction reversals at the resistive scale and field lines curved at the parallel scale of the flow. The effective is determined by whether the ion-Larmor scale is above or below the field-reversing scale: in the former case, particles undergo Bohm-like diffusion; in the latter case, particles scatter primarily off of firehose fluctuations residing at the ends of the magnetic folds, and the viscosity becomes anisotropic. The magnetic field ultimately saturates at dynamical strengths, with its spectral peak migrating toward larger scales. This feature, along with an anti-correlation of magnetic-field strength and field-line curvature and a gradual thinning of magnetic sheets into ribbons, resembles the saturated state of the large- dynamo, the primary differences manifesting in firehose/mirror-unstable regions. These results have implications for magnetic-field growth in the weakly collisional intracluster medium of galaxy clusters.

Along-slope variations in sediment lithofacies and depositional processes since the Last Glacial Maximum on the northeast Baffin margin, Canada

Twelve piston cores were used to characterize late Quaternary lithofacies, depositional processes and deglacial history along the Baffin Bay slope between Lancaster Sound and Home Bay. Core investigations show four distinct laterally correlatable lithofacies along the slope – basal and upper diamicton, laminated red brown mud, tan carbonate gravelly, sandy mud and bioturbated brown mud. Basal diamicton largely represents glacigenic debris flow deposits during a glacial advance from Baffin Island at ~25 cal ka. The distribution and character of laminated red brown mud suggests a lateral supply to Baffin Bay slope from ice-proximal meltwater plumes and turbidity currents sourced in glacial ice from both Baffin Bay shelf and Home Bay between 41.5 cal ka to ~14.2 cal ka. An upper diamicton records a lesser, localized glacial advance that ended at about 14.2 cal ka. Tan carbonate mud events represent ice-rafted, enhanced detrital carbonate delivery to the slope between ~25 cal ka and ~11 cal ka. A gradual thinning of these events, from northern to southern Baffin Bay, corroborates a northern Baffin Bay, Lancaster Sound or Nares Strait iceberg source. Proglacial facies seaward of Home Bay contain beds with slightly elevated detrital carbonate that may represent the distal edge of carbonate ice-rafted from Lancaster Sound. Baffin Bay is a type example of a polar glacial basin in which direct glacial supply predominates over the effects of glacial meltwater. As a result, axial supply from the large ice streams north of Baffin Bay (particularly Lancaster Sound) is dominant in the Baffin Bay basin and lateral supply from smaller ice streams on Baffin Island predominates on the NE Baffin Slope.

Continent‐Ocean Transition Across the Northeastern Nova Scotian Margin From a Dense Wide‐Angle Seismic Profile

AbstractTo improve constraints on rifting processes resulting in the formation of the southeastern Canadian margin, we interpret the most detailed regional 2‐D velocity model from offshore Nova Scotia constructed using wide‐angle OETR‐2009 data. This 405‐km‐long profile was collected with 78 ocean bottom seismometers. The presented data analysis and interpretation are supported by a reflection image from the coincident long streamer GXT‐2000 profile. We identify a continental zone where the full‐thickness (~30 km), three‐layered continental crust beneath the inner shelf thins sharply seaward by a listric fault that forms a 12‐km‐deep Huron Subbasin beneath a high‐velocity carbonate bank (~5.8 km/s), creating a shadow zone above tilted crustal blocks. Depth‐dependent and variable initial thinning is evidenced in all three modeled crustal layers, which, nevertheless, pinch out together at their seaward ends. More gradual and regional thinning and a local amagmatic thickening are modeled seaward beneath the slope until 70 km from the shelf break, beyond which a deepwater amagmatic continent‐ocean transition shows velocity characteristics not typical of either continental or oceanic crust. The 100‐km‐wide continent‐ocean transition is characterized by a low‐velocity (5.3–5.4 km/s), low gradient, <2‐km thick upper crust, above a high‐velocity (6.3–7.5 km/s), high gradient, <5‐km‐thick lower crust, which can be interpreted as moderately serpentinized mantle. Underneath this layer is a <5‐km‐thick low‐velocity (7.1–8.0 km/s) partially serpentinized mantle layer. A ~5‐km‐thick oceanic crust is modeled seaward. Our results suggest that amagmatic processes dominated the continental breakup in this area.

The innate origin of radial and vertical gradients in a simulated galaxy disc

We examine the origin of radial and vertical gradients in the age/metallicity of the stellar component of a galaxy disc formed in the APOSTLE cosmological hydrody- namical simulations. Some of these gradients resemble those in the Milky Way, where they have sometimes been interpreted as due to internal evolution, such as scattering off giant molecular clouds, radial migration driven by spiral patterns, or orbital reso- nances with a bar. Secular processes play a minor role in the simulated galaxy, which lacks strong spiral or bar patterns, and where such gradients arise as a result of the gradual enrichment of a gaseous disc that is born thick but thins as it turns into stars and settles into centrifugal equilibrium. The settling is controlled by the feedback of young stars; which links the star formation, enrichment, and equilibration timescales, inducing radial and vertical gradients in the gaseous disc and its descendent stars. The kinematics of coeval stars evolve little after birth and provide a faithful snapshot of the gaseous disc structure at the time of their formation. In this interpretation, the age-velocity dispersion relation would reflect the gradual thinning of the disc rather than the importance of secular orbit scattering; the outward flaring of stars would result from the gas disc flare rather than from radial migration; and vertical gradients would arise because the gas disc gradually thinned as it enriched. Such radial and vertical trends might just reflect the evolving properties of the parent gaseous disc, and are not necessarily the result of secular evolutionary processes.

Structure, mechanical properties and evolution of the lithosphere below the northwest continental margin of India

The continental breakup history at the northwest continental margin of India remained conjectural due to lack of clearly discernable magnetic anomaly identifications and the presence of several enigmatic structural/basement features whose structure was partly obscured by the Late Cretaceous Deccan magmatic event. In this study, a detailed analysis of the existing seismic and seismological data covering both onshore and offshore areas of the northwest Indian margin along with 3-D/2-D constrained potential field (gravity, magnetic and geoid) modeling has been carried out. The crustal structure and lithosphere–asthenosphere boundary (LAB) delineated across the margin provided valuable insights on the mechanism of continental extension. An analysis of the residual geoid anomaly (degree-10) map and the modeled LAB below Deccan volcanic province (DVP) revealed significant variation in upper mantle characteristics between the northwest (NW) and south central (SC) parts of DVP having thinner lithosphere in the NW part. The depth to LAB ranges 80–130 km at the margin with gradual thinning towards the western offshore having sharp gradient in the south (SC part of DVP) and gentle gradient in the north (NW part of DVP). The Moho configuration obtained from seismically constrained 3-D gravity inversion reveals that Moho depths vary 34–42 km below DVP and gradually thins to 16–20 km in the western offshore. The effective elastic thickness (Te) map computed through 3-D flexural modeling indicates that the Te values are in general lower in the region and range 12–25 km. Such lower Te values could be ascribed to the combined effect of the lithosphere stretching during Gondwana fragmentation in the Mesozoic and subsequent thermal influence of the Reunion plume. Based on the crustal stretching factors (β), Te estimates and the modeled lithosphere geometry at the margin in this study, we propose that the lithosphere below Laxmi–Gop basin region (β > 3.0) had undergone continuous stretching since India–Madagascar rifting (~ 88 Ma) /much prior to this event. However, this continuous stretching did not lead to breakup. Due to syn-rift cooling, the developed necking zone (brittle–ductile deformation) got ceased and led to the development of a new necking zone between Seychelles and Laxmi Ridge. Subsequent stretching between Seychelles and the Laxmi Ridge contemporaneous with the Deccan flood basalts eruption led to the seafloor spreading in the Western Basin (anomaly C28n). Thus, the Laxmi Ridge became a continental sliver.

Nonlinear measures and modeling to examine the role of physical and chemical crosslinking in poly(vinyl alcohol)-based crosslinked systems

Crosslinked polymers are three-dimensional network structures formed by interactions that range from weak physical associations to strong covalent bonding. The inherent complexity in their structures results in rich and diverse rheological response at large deformations. In the present work, we investigate two crosslinked materials based on poly(vinyl alcohol) (PVA) using large amplitude oscillatory shear (LAOS). Physically crosslinked PVA-borax exhibited Giesekus-like linear response, and a gradual intra-cycle strain stiffening and shear thinning at large strains. These signatures are attributed to temporary junction points and stretching of chains between crosslinks in the system. In contrast, chemically crosslinked PVA-hyaluronic acid (PVA-HA) gels exhibited a weak frequency dependence of linear moduli and intra-cycle strain stiffening and shear thickening at large strains. PVA-HA contains permanent crosslinks that move apart, along with stretching of crosslinked and uncrosslinked chains, and these features are responsible for such LAOS signatures. Based on these insights, we propose modifications to existing models and obtain quantitative description of LAOS response of both PVA-borax and PVA-HA crosslinked systems.

Nail Changes in Chilblains Mimicking Lichen Planus

Nail Changes in Chilblains Mimicking Lichen Planus

Distal turbidite fan/lobe succession of the Late Oligocene Zuberec Fm. – architecture and hierarchy (Central Western Carpathians, Orava–Podhale basin)

AbstractA part of the Upper Oligocene sand-rich turbidite systems of the Central Carpathian Basin is represented by the Zuberec Formation. Sand/mud-mixed deposits of this formation are well exposed in the northern part of the basin, allowing us to interpret the turbidite succession as terminal lobe deposits of a submarine fan. This interpretation is based on the discrimination of three facies associations that are comparable to different components of distributive lobe deposits in deep-water fan systems. They correspond to the lobe off-axis, lobe fringe and lobe distal fringe depositional subenvironments, respectively. The inferences about the depositional paleoenvironment based on sedimentological observations are verified by statistical analyses. The bed-thickness frequency distributions and vertical organization of the facies associations show cyclic trends at different hierarchical levels that enable us to reconstruct architectural elements of a turbidite fan. First, small-scale trends correspond with shift in the lobe element centroid between successive elements. Differences in the distribution and frequency of sandstone bed thicknesses as well as differences in the shape of bed-thickness frequency distributions between individual facies associations reflect a gradual fining and thinning in a down-dip direction. Second, meso-scale trends are identified within lobes and they generally correspond to the significant periodicity identified by the time series analysis of the bed thicknesses. The meso-scale trends demonstrate shifts in the position of the lobe centroid within the lobe system. Both types of trends have a character of a compensational stacking pattern and could be linked to autogenic processes. Third, a largescale trend documented by generally thickening-upward stacking pattern of beds, accompanied by a general increase of the sandstones/mudstones ratio and by a gradual change of percentage of individual facies, could be comparable to lobe-system scale. This trend probably indicates a gradual basinward progradation of lobe system controlled by allogenic processes related to tectonic activity of sources and sea-level fluctuations.

Posterior Staphylomas in Pathologic Myopia Imaged by Widefield Optical Coherence Tomography

To examine posterior staphylomas by widefield optical coherence tomography (WF-OCT) and three-dimensional magnetic resonance imaging (3D-MRI). Highly myopic patients (myopic refractive error >8.0 diopters or axial length >26.5 mm) who had previously undergone orbital 3D-MRI were examined by WF-OCT. The study included 100 eyes of 57 patients with a mean age of 67.9 ± 10.7 years (range, 44-85 years) and mean axial length of 30.0 ± 2.3 mm (range, 25.1-36.5 mm). All staphylomas detected on the 3D-MRI, except for two very large staphylomas, were visualized on the WF-OCT images. Morphologic hallmarks of the staphylomas were smoothly configured staphyloma border with a gradual thinning of the choroid and an inward protrusion of the sclera at the staphyloma edge. Comparing the detectability of the staphylomas on the WF-OCT images versus 3D-MRI revealed no significant difference between both techniques (P = 0.12; χ2 test). Comparing the staphyloma classification between both techniques showed a good concordance with a concordance index kappa of 0.61 (95% confidence interval: 0.50-0.72). A spatial relationship between the staphylomatous areas and the macula and optic nerve head was observed by WF-OCT. WF-OCT can provide tomographic images of posterior staphylomas in a resolution and size unachievable so far, and may replace 3D-MRI in assessing posterior staphylomas. Future studies using WF-OCT may explore the detailed morphologic characteristics of posterior staphylomas and give clues to the etiology of staphylomas.

ACL-deficient knee and unicompartmental OA: state of the art

Anteroposterior knee joint laxity because of anterior cruciate ligament (ACL) insufficiency produces various degenerative changes in the joint, including intra-articular damage, meniscal tears and varus morphology leading to gradual thinning of the cartilage and resulting in posteromedial osteoarthritis (OA). Two different scenarios of medial OA and ACL tear need to be identified to ensure correct surgical planning and minimise the risk of poor surgical outcome. OA development of the medial compartment of the knee may be due to ACL failure or the ACL failure can be a consequence of the arthritic phenomenon within the knee. One of the most important causes of failure in unicompartmental knee arthroplasty (UKA) surgery is the absence of ACL and the majority of failures after UKA without ACL reconstruction occur because of tibial loosening, which tends to occur early. Patients eligible for combined UKA and ACL reconstruction are typically young adults with a history of previous trauma and untreated ACL rupture, joint instability, and consequent OA of the posteromedial part of the knee. In order to obtain a correct diagnosis, a detailed medical history, complete physical examination and detailed radiographic protocol are mandatory. ACL reconstruction combined with UKA is a technically demanding procedure and must be performed in well-defined steps. A significantly higher failure rate was noted in patients who did not undergo ACL reconstruction as compared with those who received a combined procedure. Unicompartmental knee arthroplasty combined with ACL reconstruction is an excellent surgical solution for posteromedial osteoarthritis secondary to ACL deficiency.

Más vale quintaesencias que fárragos: adelgazamiento textual en el contexto de la economía de la atención y la edición digital

The recent changes in digital publishing have given rise to new developments in content creation, production, and consumption. In some cases these changes have affected preexisting functions, genres, or trends, which now have a different role in the digital environment. In others, new products have been generated that relate to the new environments and are, therefore, far from their printed reference. One of these changes is related to narrative. On the one hand, there has been a gradual thinning of the conventional narrative genres, and on the other, business models have been launched based on short texts, short stories, and short novels. In addition, new genres have emerged as twitnovels, blognovels, microfiction, etc., which have found their natural environment in the digital media. These phenomena are an example of the paradox between a supply of content that grows exponentially coupled with less and less availability of leisure time to consume them, so that competition occurs for the prevalence of one over others in a context of economy of attention and specialization of discourses.

Production- and microstructure-based fatigue assessment of metallic AISI 304/430 multilayer materials produced by hot pack rolling

Abstract Metallic multilayer materials consisting of hundreds or thousands of layers offer a high potential for broad applications in modern technology. A uniform and gradual thinning of layers can be realized by using alloys with different crystal structures in combination with the efficient and high-performance technology of hot pack rolling. However, investigations on fatigue properties, especially to evaluate the influence of the number of layers, are still missing. In the present study, the fatigue behavior of metallic multilayer materials consisting of austenitic and ferritic stainless steels AISI 304 and AISI 430 with 100 and 1400 layers are characterized by applying a time-efficient load increase procedure. Therefore, instrumented stepwise load increase tests were performed to define suitable loading parameters for a convenient comparison of fatigue properties in constant amplitude tests. A benefit of the complex production process leading to 1400 layers was verified concerning the investigated load level in the range of low cycle fatigue with a significant improvement by the factor of 3.5. The alternating current potential drop method for measurements of change in voltage was determined to be most suitable to detect microstructural changes at an early state of fatigue damage for multilayer materials. Microstructures as well as fractured surfaces were investigated using light and scanning electron microscopy to evaluate the results of the two technological manufacturing routes as well as the crack and failure behavior.

Effect of tree and branch thinning on growth, yield, and fruit quality of persimmon trees in a high-density orchard

ABSTRACTA study was conducted to evaluate the effect of branch and tree thinning on growth, yield and fruit quality in 8-year-old non-astringent persimmon (Diospyros kaki L.f.) trees in a high-density orchard over 6 years in Korea. Adjacent trees in the rows were removed in 2008 (first-year thinning) or in 2010 (gradual thinning). Trees in the second treatment also had 25% of the main scaffold branches removed in the first two seasons. Control plots were left unthinned. First-year thinning elevated leaf macro-nutrient concentrations, increased the production of short fruiting shoots (less than 20 cm) per tree, decreased water sprout development and weight of pruned biomass, and increased fruit set compared with values recorded on control trees and with gradual thinning. First-year thinning gave higher photosynthetic photon flux in the centre of the canopy and better fruit quality. There were generally only small differences in total yield across the three treatments in individual years, but much higher total marketable yield from 2010 to 2013 in the first-year thinning plots. First-year thinning improved overall tree productivity, and the gross returns were 80% higher than those of control from 2008 to 2013 when the extra cost of the thinning was taken into account.

Role of dilatation and curettage performed for spontaneous or induced abortion in the etiology of endometrial thinning.

The aim of this study was to clarify the role of dilatation and curettage (D&C) performed for spontaneous or induced abortion in the etiology of endometrial thinning. This was a retrospective and cross-sectional study of 310 infertile patients from January 2013 through December 2015. Endometrial thickness observed 5-7 days after ovulation in a natural menstrual cycle was correlated with the number of D&C noted in each patient's history. Study 1 was an investigation of patients without D&C (group A: n = 232) and patients with D&C performed for spontaneous abortion (group B: n = 46). Study 2 was an investigation of patients in group A and patients with D&C performed for induced abortion (group C: n = 32). A significant negative correlation (P < 0.01) between endometrial thickness and number of D&C was observed in both studies. The mean endometrial thickness of the patients in group A was 10.9 ± 2.1 mm. The mean endometrial thickness of the patients in group B with one and ≥two D&C was 7.9 ± 2.3 and 6.9 ± 2.9 mm, respectively. The mean endometrial thickness of the patients in group C with one and ≥two D&C was 9.1 ± 2.3 and 7.8 ± 2.0 mm, respectively. There was a tendency toward gradual endometrial thinning following repeated procedures and the number of previous D&C was significantly associated with endometrial thinning (P < 0.001) in both studies. D&C performed for spontaneous or induced abortion may play a causal role in endometrial thinning.

Size-Dependent Structure Relations between Nanotubes and Encapsulated Nanocrystals.

The structural organization of compounds in a confined space of nanometer-scale cavities is of fundamental importance for understanding the basic principles for atomic structure design at the nanolevel. Here, we explore size-dependent structure relations between one-dimensional PbTe nanocrystals and carbon nanotube containers in the diameter range of 2.0-1.25 nm using high-resolution transmission electron microscopy and ab initio calculations. Upon decrease of the confining volume, one-dimensional crystals reveal gradual thinning, with the structure being cut from the bulk in either a <110> or a <100> growth direction until a certain limit of ∼1.3 nm. This corresponds to the situation when a stoichiometric (uncharged) crystal does not fit into the cavity dimensions. As a result of the in-tube charge compensation, one-dimensional superstructures with nanometer-scale atomic density modulations are formed by a periodic addition of peripheral extra atoms to the main motif. Structural changes in the crystallographic configuration of the composites entail the redistribution of charge density on single-walled carbon nanotube walls and the possible appearance of the electron density wave. The variation of the potential attains 0.4 eV, corresponding to charge density fluctuations of 0.14 e/atom.

An extended Landau–Levich model for the dragging of a thin liquid film with a propagating surface acoustic wave

In this paper we revisit the Landau and Levich analysis of a coating flow in the case where the flow in the thin liquid film is supported by a Rayleigh surface acoustic wave (SAW), propagating in the solid substrate. Our theoretical analysis reveals that the geometry of the film evolves under the action of the propagating SAW in a manner that is similar to the evolution of films that are being deposited using the dip coating technique. We show that in a steady state the thin-film evolution equation reduces to a generalized Landau–Levich equation with the dragging velocity, imposed by the SAW, depending on the local film thickness. We demonstrate that the generalized Landau–Levich equation has a branch of stable steady state solutions and a branch of unstable solutions. The branches meet at a saddle-node bifurcation point corresponding to the threshold value of the SAW intensity. Below the threshold value no steady states were found and our numerical computations suggest a gradual thinning of the liquid film from its initial geometry.

Megaflaps adjacent to salt diapirs

Megaflaps are steep stratal panels that extend far up the sides of diapirs or their equivalent welds. They have multiple-kilometer fold widths and structural relief and are thus distinct from smaller-scale composite halokinetic sequences. Maximum dips range from near-vertical to completely overturned. Although overturned megaflaps are associated with flaring salt, there is no direct link between megaflap formation and the initiation of salt sheets. Strata within a megaflap are usually convergent, and the lower boundary is typically concordant with the top salt. The upper boundary ranges between a prominent onlap surface and a more diffuse zone of gradual rotation and thinning, and growth strata likewise display both onlap and stacked wedge geometries. We use quantitative cross-section restoration to elucidate the origin and development of megaflaps. Megaflaps typically represent the relatively thin roofs of early salt structures that include single-flap active diapirs, passive diapirs, salt pillows, and salt sheets. They develop during halokinetic drape folding as the minibasin sinks, during contractional squeezing of the diapir and its roof, or during some combination of the two. The kinematics are dominated by either limb rotation or kink-band migration, in which roof strata move through a fold hinge into a lengthening steep megaflap. Both restoration results and direct field evidence suggest that internal strain is minor, with little bed lengthening and thinning. Recognition and understanding of megaflaps are critical to successful petroleum exploration of three-way truncation traps against salt. Megaflaps also have implications for the lateral seal of stratigraphic traps and fluid pressures in minibasins.

Effects of xanthan and sugar on the release of aroma compounds in model solution

AbstractThe effects of the interaction of xanthan and sugar on the release of aroma compounds (α‐pinene, ethyl acetate, ethyl butyrate, perillaldehyde, hexenal, and d‐limonene) were investigated in model solutions (xanthan, sugar and xanthan‐sugar solutions). The released aroma compounds were analysed by solid‐phase microextraction and gas chromatography‐mass spectrometer (SPME/GC‐MS). The results showed that the six aroma compounds decreased differently in the 0.4 g·L‐1 xanthan solution. A slightly stronger release of these aroma compounds in glucose solution was observed than that in sucrose solution. The release of these aroma compounds increased in the xanthan solution after the addition of the sucrose. This indicated that the release of these aroma compounds was inhibited in the xanthan solution. But the addition of sucrose in the xanthan solution could promote the release of the aroma compounds. Additionally, the rheology results showed that the xanthan solution exhibited a gradual shear thinning and the C* of xanthan was 2 g·L‐1. However, the concentrations of the xanthan solution which could inhibit the release of the six aroma compounds were not fully consistent with C*. And this indicated that viscosity was not the main factor influencing the release of aroma compounds in the xanthan solution. Copyright © 2016 John Wiley &amp; Sons, Ltd.

The cardiac MRI characteristics of patients with pure T-wave inversion and wall thickness less than apical hypertrophic cardiomyopathy diagnostic criteria

Objective To investigate the cardiac MRI characteristics of patients with pure T-wave inversion and wall thickness less than apical hypertrophic cardiomyopathy diagnostic criteria. Methods Thirty-one patients from June 2012 to June 2014 with pure T-wave inversion and 32 healthy controls were retrospectively enrolled into this study. The left ventricular (LV) wall thickness was measured based on an AHA 17-segment model, as well as the apical angles (apA). The variations of LV thickness from base to apex, from the septum to free wall, and the ratio of maximal apical thickness to segment 4 were calculated and analysed. One-way ANOVA was used to analysis the thickness differences among the basal, middle and apical walls of left ventricular. In addition, student t test was also used to compare the differences of apical thickness, apA, LV ejective fraction and other cardiac function parameters of MRI between the two groups. Results In control groups the LV wall showed a trend of gradual thinning from base to apex. The thicknesses of basal, middle and apical were (7.51 ± 0.87), (6.27 ± 1.11), (3.57 ± 0.52) mm, a statistically significant difference (F=171.78, P<0.01). The ratio of maximal apical segment to segment 4 was 0.63±0.20. The LV wall of patients with pure T-wave inversion lost the trend of gradual thinning from base to apex. The thicknesses of basal, middle and apical also showed statistically significant difference (F=6.81, P<0.01) , which were (7.70 ± 0.92), (6.55 ± 0.94), (7.35 ± 1.14) mm, respectively. The ratio of the maximal apical thickness to segment 4 was 1.14±0.24 in patients. The apical thickness of patients was significantly greater than that of control's (t=- 11.81, P<0.01). The apA of patients were significantly decreased as controls (85.21°±12.09° and114.99°± 10.88°, t=-10.27, P< 0.05). Conclusions Although in patients with pure T-wave inversion, even if the wall thickness of LV less than the apical hypertrophic cardiomyopathy diagnostic criteria, the LV morphological variations has apparently occurred. Therefore, these subjects may be included into a pre-clinical scope or a early stage of apical hypertrophic cardiomyopathy. Key words: Magnetic resonance imaging; Cardiomyopathy, hypertrophic