THUẬT NGỮ SIÊU ÂM ĐÀN HỒI

GLOSSARY for US Elasto Terminology 

BẢNG TỪ VỰNG CHUYÊN NGÀNH VỚI CÁC ĐỊNH NGHĨA  MỘT SỐ THUẬT NGỮ ĐÀN HỒI

acoustic radiation force

lực bức  xạ  âm=hiện tượng vật lý do tương tác sóng âm với môi trường truyền qua tạo bởi chuyển đổi động lượng từ sóng âm với môi trường, khởi lên từ hấp phụ và/hoặc tán xạ/phản hồi của năng lượng âm; thuật ngữ ‘bức xạ âm’ dùng cho sự truyền năng lượng âm, là một dạng bức xạ không ion-hóa.

- A physical phenomenon resulting from the interaction of an acoustic wave with the medium through which it is propagating, generated by a transfer of momentum from the wave to the medium, arising from the absorption and/or scattering/reflection of acoustic energy; the term ‘acoustic radiation’ refers to the propagation of acoustic energy, which is a form of non-ionizing radiation.

acoustic radiation force impulse (ARFI)

xung lực bức xạ âm (ARFI)=như xung tạm thời [rất ngắn, 1miligiây] của lực bức xạ âm, tạo bởi một chùm âm tập trung. Trong sách báo kỹ thuật, thuật ngữ này thường dùng thay đổi cho ‘tạo hình ARFI’, tuy nhiên, trong sách báo thương mại và lâm sàng, thuật ngữ này được dùng cho cả tạo hình ARFI lẫn định lượng ARFI.

- A temporally impulse-like (i.e., very short duration, 1 msec) acoustic radiation force, typically generated with a focused acoustic beam. In the technical literature, this term has been used interchangeably with ‘ARFI imaging’, however, in the clinical and commercial product literature, this term has been used to refer to both ARFI imaging and quantitative ARFI.

acoustic radiation pressure

áp suất bức xạ âm= lực bức xạ âm tác động trên bề mặt một vật trong đường truyền sóng âm

- The acoustic radiation force exerted on the surface of an object placed in the path of a propagating acoustic wave.

ARFI imaging

tạo hình ARFI= dạng tạo hình đàn hồi dùng tác động xung lực bức xạ âm, và tạo ra hình ảnh dời chỗ mô trong chùm ARFI kích thích. Kích thích ARFI được dùng để khảo sát những vị trí bên lân cận theo chuỗi trong vùng quan tâm, với những hình ảnh tương đương với dời chỗ mô tương đối. Thông tin tương tự như từ các hình ảnh căng tạo ra do lực đè từ ngoài.

- A form of elasticity imaging that uses acoustic radiation force impulse (ARFI) excitation, and generates images related to the corresponding tissue displacement within the ARFI excitation beam. ARFI excitations are used to sequentially interrogate adjacent lateral positions within a specified field of view, with the corresponding images reflecting relative tissue displacement. The information in these images is similar to that from strain images generated with external compression

ARFI quantification

định lượng ARFI=thuật ngữ dùng nhiều trong y văn nhằm mô tả kỹ thuật đàn hồi sóng biến dạng từng điểm  của Siemens VTTMQ.  Xem thêm point shear wave elastography.

- A term widely used in the clinical literature to describe the point shear wave elastography method employed by the Siemens VTTMQ feature. See also point shear wave elastography

axial strain

căng theo trục=căng theo hướng lực tác động. Trong đàn hồi, nói chung là theo hướng chùm âm, hay hướng vào chiều sâu.

- Strain in the direction of the applied force. In elastography, this is generally in the direction of the acoustic beam, or the depth direction.

bulk modulus

mô đun đàn hồi  khối,  mô đun biến dạng thể tích=đặc trưng vật chất căn bản của sự chống đối của thay đổi khối lượng do áp suất tăng.  Tương đương với chống đối với tăng tỷ trọng khi áp suất tăng. Đàn hồi khối là phản nghĩa với sự đè ép.

- A fundamental material property that quantifies the resistance to volume change with increasing pressure. It is equivalent to the resistance to increase density with increasing pressure. The bulk modulus is the inverse of compressibility.

compressibility

đè ép=đo thay đổi khối lượng tương đối khi đáp ứng với thay đổi áp suất. Đè ép là phản nghĩa của đàn hồi khối. Ghi nhận rằng có khác biệt giữa đoạn nhiệt (đẳng entropy), đè ép  và đẳng nhiệt (nhiệt độ không đổi), nhưng sự khác biệt không đủ cho hầu hết nhu cầu trong đàn hồi.

- A measure of the relative volume change in response to a pressure change. Compressibility is the inverse of the bulk modulus. Note that there is a distinction between adiabatic (constant entropy) compressibility and isothermal (constant temperature) compressibility, but the distinction is beyond the scope of most needs in elastography.

compressional wave

sóng ép= sóng cơ học truyền theo hướng phần tử dời chỗ. Sóng ép tăng truyền (và kế tiếp giảm truyền) trong áp suất tại chỗ hay tỷ trọng. Cũng là sóng âm, sóng âm thanh, sóng áp lực, sóng p hay sóng dọc.

- A mechanical wave that propagates in the direction of the particle displacement. A compressional wave is a propagating increase (and then decrease) in the local pressure or density. These are also known as acoustic waves, sound waves, pressure waves, p-waves or longitudinal waves.

dispersion (acoustics)

tán âm=hiện tượng sóng phân cách theo thành phần tần số khi truyền. Tán âm gây ra bởi vận tốc pha trong vật chất tùy thuộc tần số (nói chung, thành phần tần số sóng cao hơn truyền đi nhanh hơn các thành phần tần số sóng thấp hơn).

- The phenomena of a wave separating into its frequency components as it propagates. Dispersion is caused by the phase velocity in the material being frequency-dependent (generally, higher frequency component of the wave traveling faster than lower frequency components).

dispersive medium

môi trường tán âm=vật chất có tán âm.

- A material that exhibits dispersion.

elastic modulus

mô đun đàn hồi=định lượng khả năng vật chất biến dạng chống lại lực tác động. Có nhiều loại mô đun đàn hồi chuyên biệt cho các loại lực (hay ứng suất, stress) và các loại biến dạng (hoặc căng); thí dụ như mô đun biến dạng khối, mô đun ngang, mô đun biến dạng dọc, và hệ số biến dạng ngang Poisson.

- A quantity relating the ability of a material to resist deformation when a force is applied. There are many elastic moduli that are specific to the type of force (or stress) and the type of deformation (or strain); see, for example, bulk modulus, shear modulus, Young’s modulus, and Poisson’s ratio.

elastic nonlinearity

đàn hồi phi tuyến=tăng độ dốc đường cong ứng suất-biến dạng với gia tăng căng. Đo tăng độ cứng của vật chất khi gia tăng biến dạng vật chất.

- The increase in the slope of the stress-strain curve with increasing strain. It is a measure of the increased  stiffness of a material as the deformation of that material increases.

elastogram

bản đồ đàn hồi= hình ảnh các đặc điểm (nhày-) đàn hồi mô

- An image of the (visco-) elastic properties of tissue.

elastography

đo đàn hồi=phương pháp tạo hình cung cấp thông tin liên quan đến độ cứng mô (hay đặc điểm đàn hồi khác).

 Any imaging method that provides information related to the stiffness (or another elastic property) of tissue.

group velocity

vận tốc nhóm=vận tốc ở dạng toàn thể của truyền sóng (sự điều biến, đường bao). Là tốc độ sóng kết hợp với tổng trọng số các vận tốc pha lẽ cấu tạo nên sóng.

- The velocity at which the overall shape (modulation, envelope) of a wave propagates. It is the wave speed associated with the weighted sum of the individual phase velocities comprising the wave.

indentation test

test làm lõm, test đánh giá đặc điểm cơ học vật chất=test thiết kế đo độ cứng vật chất (nói chung có khả năng chống lại biến dạng dẻo hay gãy). Đôi khi cách này dùng đánh giá mô đun biến dạng dọc của vật chất.

- A method for estimating the mechanical properties of a material. Specifically, indentation tests are designed to measure the ‘‘hardness’’ of a material (generally, its ability to resist plastic deformation or fracture). This approach is sometimes used to estimate the Young’s modulus of a material.

Kilopascal

Kilopascal=một ngàn Pascals (kPa)

- One thousand Pascals (kPa).

loss modulus

loss modulus [mô đun mất] = mô tả lượng không đàn hồi (hoặc nhày) của vật chất nhày-đàn hồi đáp ứng lực tác động (ứng xuất, stress). Loss modudus kết hợp với storage modulus (đáp ứng đàn hồi hay năng lượng hàm trữ) diển tả mô đun phức động [complex modulus] (dynamic modulus).

- The quantity describing inelastic (or viscous) response of a viscoelastic material to an applied force (stress). The loss modulus combines with the storage modulus (the elastic response or stored energy) to express the complex modulus.

magnetic resonance elastography (MRE)

cộng hưởng từ đàn hồi (MRE)=phương pháp tạo hình đàn hồi dùng máy rung ngoài tạo nên sóng biến dạng, và tạo hình cộng hưởng từ theo dỏi đáp ứng mô tạo ra hình mô đun ngang (liên quan đến mô đun biến dạng dọc bằng một yếu tố 1/3 theo một số giả định đơn giản hóa nhất định)

- An elasticity imaging method that uses an external vibration device to generate shear waves, and Magnetic Resonance Imaging to monitor the tissue response to generate images of shear modulus (which is related to Young’s modulus by a factor of 1/3 under certain simplifying assumptions).

modulus of rigidity

mô đun độ cứng= xem mô đun ngang

- See shear modulus.

pascal

pascal=đơn vị đo áp suất, ứng xuất, mô đun độ cứng, mô đun biến dạng dọc hay độ bền kéo. Đặt tên theo nhà toán học và vật lý Pháp Blaise Pascal, một pascal (Pa) tương đương với một newton trên mét vuông, và 1 kPascal ứng với 0,01 atmotphe [đơn vị đo áp suất]

- A unit measure of pressure, stress, shear modulus, Young’s modulus or tensile strength. Named for the French mathematician and physicist Blaise Pascal, one pascal (Pa) is equivalent to one newton per square meter, and 1 kPa is approximately 0.01 atmospheres.

phase velocity

vận tốc pha=tốc độ khi phase của sóng, hay bất kỳ thành phần tần số đơn của sóng, truyền trong không gian. Là chỉ số của độ dài sóng với chu kỳ sóng.

- The rate at which the phase of a wave, or any single frequency component of the wave, travels in space. The phase velocity is the ratio of the wavelength to the period of the wave.

point shear wave elastography

đàn hồi đo theo điểm sóng biến dạng= phương pháp  đánh giá độ đàn hồi bằng cách tạo ra sóng biến dạng với lực bức xạ âm và ghi lại số đo định lượng độ cứng (cả tốc độ sóng biến dạng hoặc mô đun biến dạng dọc), số đo này diễn tả bình quân số đo một khu vực giả định đồng dạng trong vùng quan tâm.

- An elasticity estimation method that generates a shear wave with acoustic radiation force, and reports a quantitative stiffness metric (either shear wave speed or Young’s modulus) that represents the average of that metric within a local region of interest that is assumed to be homogeneous.

Poisson’s ratio

hệ số biến dạng ngang Poisson=đặc tính vật chất cơ bản định lượng hệ số âm của căng ngang với căng dọc trong vật chất đàn hồi. Với vật chất đẳng hướng, hệ số Poisson nằm giữa -1 và 0,5. Vật chất không đè ép được có hệ số Poisson là 0,5. Đặt tên theo nhà toán học và vật lý Pháp Simeon Denis Poisson, hệ số Poisson, như mô đun ngang, mô tả sự chống đối của vật chất khi thay đổi dạng, nhưng hệ số Poisson liên quan với thay đổi kích thước theo hướng tải tác động lên thay đổi dạng của vật chất theo hướng thẳng góc .

- A fundamental material property that quantifies the negative ratio of transverse strain to longitudinal strain in an elastic material. For isotropic materials, Poisson’s ratio lies between -1 and 0.5. Incompress -ible materials have a Poisson’s ratio of 0.5. Named after the French mathematician and physicist Sim- eon Denis Poisson, Poisson’s ratio, like the shear modulus, describes the resistance of a material to changes in shape, but Poisson’s ratio relates a change in dimension in the direction of the applied load to the change in shape of the material in the perpendicular direction.

quasi-static loading

tải chuẩn-tĩnh=ngược lại với tải động. Ứng dụng của ứng xuất xảy ra đủ chậm như là hiệu ứng quán tính không đáng kể (độc lập thời gian của tải và khối quán tính có thể không biết)

- The application of stress that happens sufficiently slowly such that the inertial effects are negligible (time dependence of the load and inertial mass can be ignored). This is in contrast to dynamic loading.

radiation force

lực bức xạ= xem lực bức xạ âm

- See acoustic radiation force.

shear modulus

mô đun ngang=đặc tính vật chất định lượng sự chống đối của vật chất để thay đổi dạng trong hệ số shear stress với  shear strain, và cũng là modulus of rigidity. Đơn vị là Pascals.

- A material property that quantifies the resistance of a material to change its shape in shear ratio of the shear stress to the shear strain and is also known as the modulus of rigidity. The units of the shear modulus are Pascals.

shear strain

biến dạng căng, biến dạng trượt=biến dạng vật thể trong đó một  mặt phẳng cắt ngang qua vật thể dời chỗ song song với chính nó.Biến dạng như vậy là kết quả của biến dạng căng.

- The deformation of a body in which a cross sectional plane through the body is displaced parallel to itself. Such a deformation is the result of a shear stress.

shear stress

ứng xuất biến dạng= thành phần của ứng xuất trên một bề mặt tiếp tuyến với bề mặt. Đối với mặt phẳng, vectơ lực trong mặt phẳng bề mặt. Đơn vị của ứng xuất biến dạng là Pascals.

- The component of stress on a surface that is tangential to the surface. For flat surfaces, the force vector is in the plane of the surface. The units of shear stress are Pascals.

shear viscosity

độ nhày biến dạng=chống đối của  chất dịch với biến dạng (dòng chảy). Chất dịch không có độ nhớt gọi là ‘chất dịch lý tưởng’. Các chất dịch chảy dễ dàng, như nước, có độ  nhớt thấp. Các dịch kháng chảy có độ nhớt cao, như rỉ mật. Đơn vị của độ nhày nhớt là Pascal-giây.

- The resistance of a fluid to deformation (flow). A fluid with no viscosity is called an ‘ideal fluid’. Fluids that flow readily, such as water, are low viscosity. Fluids that resist flow, such as molasses, are high viscosity. The units of viscosity are Pascal – second.

shear wave

sóng biến dạng=

- A mechanical wave that propagates in the direction perpendicular to the particle displacement in an infinite material. These are a special type of transverse waves and are also known as s-waves.

shear wave elastography

đàn hồi sóng biến dạng=phương pháp tạo hình đàn hồi dùng  lực bức xạ âm tạo ra sóng biến dạng  và tạo ra hình ảnh định lượng của việc đo độ cứng (nơi đó color bar trình bày cả mô đun Young hoặc tốc độ sóng biến dạng)

- An elasticity imaging method that uses acoustic radiation force to generate shear waves and generates quantitative images of a stiffness metric (where the color bar represents either Young’s modulus or shear wave speed).

shear wave imaging

tạo hình sóng biến dạng=phương pháp đàn hồi kích thích và theo dỏi truyền sóng biến dạng trong mô và ghi lại giá trị định lượngnliên quan đến độ cứng (thí dụ, tốc độ sóng biến dạng, mô đun biến dạng dọc, mô đun ngang).

- An elastography method that induces and monitors shear wave propagation in tissue and reports a quantitative value related to the stiffness (i.e., shear wave speed, Young’s modulus, shear modulus).

SNR (signal to noise ratio)

- The ratio of the amount of signal divided by the amount of noise present in data.

Stiffness

độ cứng

- The extent to which an object resists deformation in response to an applied force.

strain

căng=

- A measure of relative deformation. The most commonly used form is referred to as ‘‘infinitesimal strain’’ or ‘‘engineering strain,’’ which is the ratio of the total deformation (DL) divided by the initial dimension of the material (L), so that strain 5 DL/L.

strain imaging

tạo hình căng=phương pháp đàn hồi tạo nên hình ảnh căng mô, liên quan cả độ cứng cấu trúc của đối tượng và mô đun ngang của mô.

- An elastography method that generates images of tissue strain, which is related to both the structural stiffness of the object and the shear modulus of tissue.

stress

ứng xuất=ứng xuất=lực trên mỗi đơn vị vùng tác động trên vật thể. Ứng xuất có thể từ lực trên bề mặt vật thể hoặc do phần tử nội tại (thành phần thể tích) tácđộng trên phần tử lân cận (thành phần thể tích). Đơn vị của ứng xuất  là Pascal. Xem các loại ứng xuất cá biệt như compressive stress, shear stress và  uniaxial stress.

- The force per unit area acting on a body. Stresses can result from forces on the surface of the body or can be due to an internal particle (volume element) acting on an adjacent particle (volume element). The units of stress are the Pascal. See also particular types of stress such as compressive stress, shear stress and uniaxial stress.

stress concentration

tập trung ứng suất= ứng xuất khu trú cao đáng kể hơn bình quân ứng xuất xung quanh. Thường được tạo ra từ dạng bề mặt không đều  hoặc được vùi khu trú các đặc điểm nhày đàn hồi khác nhau.

- Localized stress that is considerably higher than the average surrounding stress. This is usually caused by an irregular surface shape or a local inclusion with different viscoelastic properties.

stress decay

phân rã ứng xuất=mất ứng xuất trong đối tượng cũng như với thời gian (như trong thực nghiệm xã stress) hoặc trong  không gian (như do hiệu ứng nhiễu xạ từ bề mặt làm lõm)

- A loss in stress in an object either with time (such as in a stress relaxation experiment) or in space (such as due to diffraction effects from a surface indenter).

structural stiffness

độ cứng cấu trúc=độ cứng khởi phát từ cấu trúc vật chất; độ cứng một đối tượng khởi phát từ cả mô đun ngang và hiệu ứng của cấu trúc. Ví dụ, một màng mỏng sẽ có độ cứng cấu trúc thấp hơn và, do vậy, độ cứng thấp hơn, so với màng dày hơn của cùng mô đun ngang, hoặc một ống tạo bởi một tờ giấy thì cứng hơn một tờ giấy do những khác biệt về độ cứng cấu trúc.

- Stiffness arising from the structure of an object; an object’s stiffness arises from both its shear modulus and the effect of its structure. For example, a thin membrane will have a lower structural stiffness and, hence, lower stiffness, than a thicker membrane of the same shear modulus, or a tube formed from a sheet of paper is stiffer than the sheet of paper due to the differences in structural stiffness.

transient elastography

đàn hồi thoáng qua=phương pháp đánh gía đàn hồi bằng cách tạo ra sóng biến dạng với máy rung ngoài và ghi lại số đo độ cứng định lượng (mô đun Young), số đo này là bình quân của việc đo trong một vùng giả định đồng dạng khu trú.

- An elasticity estimation method that generates a shear wave with an external vibration and reports a quantitative stiffness metric (Young’s modulus) that represents the average of that metric within a local region that is assumed to be homogeneous.

transverse strain
căng ngang =thành phần của căng thẳng góc với trục vật chất thích hợp

- That component of strain perpendicular to some relevant axis of the material.

transverse wave

sóng ngang=sóng truyền theo hướng thẳng góc với dời chỗ của vật chất

- A wave that propagates in a direction that is perpendicular to the particle displacement.

uniaxial strain

căng không theo trục=

- An idealized condition in which a planar surface (or cross section through a material) has uniform

displacement perpendicular to the plane of the surface (or cross section).

uniaxial stress

ứng xuất  không theo trục=

- An idealized condition in which a planar surface (or cross section through a material) has uniformly distributed force over the entire surface and that force is perpendicular to the plane of the surface (or cross section).

viscoelastic material

vật chất nhày đàn hồi=vật chất như polymer hay mô không đàn hồi hoàn toàn. Vật chất đàn hồi hoàn toàn trữ toàn bộ năng lượng từ sự biến dạng và phóng thích năng lượng này [như khi trở lại trạng thái ban đầu] khi lực tác động bị gỡ bỏ. Khi có tải động tác động vào vật chất đàn hồi hoàn toàn, căng cùng phase với ứng xuất. Đối với dịch nhớt thuần nhất, căng sẽ chậm so với ứng xuất 90 độ. Vật chất nhày đàn hồi đáp ứng bất kỳ lúc nào giữa 2 trường hơp trên.

- A material, such as a polymer or tissue, that is not perfectly elastic. A perfectly elastic material stores all energy from a deformation and releases that energy (such as to return to its initial state) when the applied force is removed. When a dynamic load is applied to a perfectly elastic material, the strain is in phase with the stress. For a purely viscous fluid, the strain will lag the stress by 90 degrees. A viscoelastic material will respond somewhere between these ideal cases.

viscosity

độ nhày=Xem độ nhày biến dạng

- See shear viscosity.

wave

sóng=là sự nhiễu loạn hay dao động truyền qua môi trường.

- A disturbance or oscillation that travels through a medium.

Young’s modulus

mô đun đàn hồi dọc=đặc điểm vật chất cho thấy khó làm biến dạng vật chất bằng cách làm giãn hay đè ép. Là tỷ số của ứng xuất không theo trục và căng không theo trục (cả với đè nén hoặc tải trọng kéo đứt)

- A material property that indicates how difficult it is to deform a material by stretching or compression. It is the ratio of the uniaxial stress to the uniaxial strain (either compressive or tensile loading).

WFUMB GUIDELINES ELASTOGRAPHY 2015-2016

WFUMB GUIDELINES ELASTOGRAPHY 2015-2016
Download theo link

- Part 1 Basic Shiina 2015.

- Part 2 Breast_Barr   2015.

- Part 3 Liver_Ferraioli   2015.

- Part 4 Thyroid_Cosgrove   2016.

- Part 5 Prostate_Barr   2016.

ACR CEUS LI-RADS 2016

ACR CEUS LI-RADS 2016

Liver Imaging Reporting and Data System

ACR CEUS LI-RADS, or CEUS LI-RADS for short, is a standardized system for technique, interpretation, reporting, and data collection for contrast-enhanced ultrasound (CEUS) exams in patients at risk for developing HCC. The system currently includes a lexicon of controlled terminology, schematic illustrations, and a categorization algorithm. A complete illustrative atlas, reporting guidelines, and educational material are in development. CEUS LI-RADS will be updated as experience accrues, as knowledge add technology advance, and in response to user feedback.

ACR CEUS LI-RADS was developed by a working group of national and international experts. The group is Chaired by Dr. Yuko Kono, MD, of the University of California, San Diego. Members include radiologists and hepatologists from the United States, Canada, Europe, and Asia. The group was convened in April 2014. Beta versions of the CEUS LI-RADS algorithm were presented at national and international conferences in 2015 and 2016. Feedback was solicited. Based on the feedback and iterative consensus, the working group refined and in 5-21-16 finalized the CEUS LI-RADS algorithm. The algorithm was officially approved by the ACR LI-RADS Steering Committee on 6-24-16 and submitted to the ACR for public release on 6-24-16.

LI-RADS-CEUS - Proposal for a Contrast-Enhanced Ultrasound Algorithm for the Diagnosis of Hepatocellular Carcinoma in High-Risk Populations.

Schellhaas B1, Wildner D1, Pfeifer L1, Goertz RS1, Hagel A1, Neurath MF1, Strobel D1.

Author information

Abstract

Purpose: To develop a contrast-enhanced ultrasound algorithm (LI-RADS-CEUS = liver imaging reporting and data system with contrast-enhanced ultrasound) for the diagnosis of hepatocellular carcinoma (HCC) in patients at risk. 

Materials and Methods: A CEUS algorithm (LI-RADS-CEUS) was designed analogously to CT- and MRI-based LI-RADS. LI-RADS-CEUS was evaluated retrospectively in 50 patients at risk with confirmed HCC or non-HCC lesions (test group) with subsequent validation in a prospective cohort of 50 patients (validation group). Results were compared to histology, CE-CT and CE-MRI as reference standards. 

Results: Tumor diagnosis in the test group/validation group (n = 50/50) were 46/41 HCCs, 3/3 intrahepatic cholangiocellular carcinomas (ICCs) and 1/6 benign lesions. The diagnostic accuracy of LI-RADS-CEUS for HCC, ICC and non-HCC-non-ICC-lesions was 89 %. For the diagnosis of HCC, the diagnostic accuracy was 93.5 % (43/46 cases) in the test group and 95.1 % (39/41 cases) in the validation group. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 94.3 %, 66.6 %, 94.3 % and 66.6 %, respectively (mean values from both cohorts). Histological findings of HCC were available in 40 versus 23 cases (in total: G1 / G2/G3: 15/35/13). Arterial hyperenhancement was seen in 68/87 (78.2 %) of HCCs. Arterial hyperenhancement with subsequent portal venous or late phase hypoenhancement was seen in 66 % of HCCs. 

Conclusion: LI-RADS-CEUS offers a CEUS algorithm for standardized assessment and reporting of focal liver lesions in patients at risk for HCC. Arterial hyperenhancement in CEUS is the key feature for the diagnosis of HCC in patients at risk, whereas washout is not a necessary prerequisite.

© Georg Thieme Verlag KG Stuttgart · New York.

ULTRASOUND at a DISTANCE: Tele-Mentored US Supported Medical Interactions Project

“We were MacGyvering off-the-shelf technology, cobbling this idea together on evenings and weekends, working around our schedules as clinicians,” says trauma surgeon Andrew Kirkpatrick, principal investigator on the Tele-Mentored Ultrasound Supported Medical Interactions (TMUSMI) project and Cumming School of Medicine professor. “This NEST funding is so exciting because it allows us to formalize our work and will accelerate our program a thousand-fold.”

The goal of Kirkpatrick’s group, which is co-led by former NASA flight surgeon Douglas Hamilton, is to develop protocols allowing an inexperienced clinician to be mentored at a distance through any unfamiliar medical assessment including, if necessary, ultrasound imaging.

The premise is that ultrasound technology is extremely useful, it’s getting cheaper and more available. But it requires experience to use, especially to avoid misinterpretation. And while available communications, like Skype, can work to facilitate distance diagnoses and assessments, the issue remains that — in trauma care particularly — time is critical. A delay of even five seconds is too much. So the challenge is to create smart, simplified ultrasound that provides instantaneous two-way communication.

“We picture ultrasound being as available one day as the defibrillators at the rink or the mall,” Kirkpatrick says. The team began this work 15 years ago; they are the most published people in the world in the field with a combined 50 years of experience designing and studying tele-medical instrumentation.

Their goals are likewise lofty: “We want to deliver rural, remote medical communities — and even space expeditions — with the speed, accuracy and convenience of urban-based point-of-care ultrasound and other lifesaving medical procedures.”

New Earth-space technologies are capturing, analyzing and visualizing our Earth-space environment through unprecedented advances in sensors, platforms and systems. We are on the cusp of a technological revolution in our ability to sense and monitor our natural environment and built world — with widespread applications for humanity. From the oldest science (astronomy) to the latest evolution of geomatics, University of Calgary researchers on the New Earth-Space Technologies Research Strategy team are providing information that is constantly changing how we make decisions about our world.

U.S. Preventive Services Task Force finalized its recommendation against the screening with neck palpation or ultrasound for thyroid cancer

USPSTF discourages thyroid cancer screening

By Erik L. Ridley, AuntMinnie staff writer

May 9, 2017 -- Citing the lack of evidence for an overall benefit as well as the risk of harm from overdiagnosis and overtreatment, the U.S. Preventive Services Task Force (USPSTF) has finalized its recommendation against the use of screening with neck palpation or ultrasound for thyroid cancer in low-risk, asymptomatic adults.

Updating its previous guidance from 1996, the USPSTF gave thyroid cancer screening a D grade, which indicates the task force believes there is moderate or high certainty that a medical service has no net benefit or that the harms outweighs its benefits. The D grade kept to the task force's draft recommendation published in November.

Writing in a statement published in the May 9 issue of the Journal of the American Medical Association, Vol. 317:18, pp. 1882-1887), the task force said it found inadequate evidence to estimate the accuracy of neck palpation or ultrasound as a screening test for thyroid cancer in asymptomatic people. It also pointed to a lack of adequate direct evidence that the screening tests improved health outcomes

"However, the USPSTF determined that the magnitude of benefit can be bounded as no greater than small, based on the relative rarity of thyroid cancer, the apparent lack of difference in outcomes between patients who are treated versus only monitored (i.e., for the most common tumor types), and the observational evidence demonstrating no change in mortality over time after introduction of a population-based screening program," the task force wrote.

Furthermore, the task force found inadequate direct evidence to assess the harm of screening for thyroid cancer in asymptomatic adults. However, the "USPSTF found adequate evidence to bound the magnitude of the overall harms of screening and treatment as at least moderate, based on adequate evidence of serious harms of treatment of thyroid cancer and evidence that overdiagnosis and overtreatment are likely consequences of screening," the group wrote.

As a result, the USPSTF said it concluded with moderate certainty that thyroid cancer screening in asymptomatic adults results in harms that outweigh the benefits.

Review process

The USPSTF's decision was based on an evidence report and systematic review prepared for the task force by a team led by Dr. Jennifer Lin of Kaiser Permanente Center for Health Research in Portland, OR. The group initially reviewed 707 full-text articles from searches of Medline, PubMed, and the Cochrane Central Register of Controlled Trials for relevant studies. The researchers then settled on 67 studies for the final analysis. Two reviewers independently appraised the papers and extracted study data from those they deemed to have fair-to-good quality (JAMA, May 9, 2017, Vol. 317:18, pp. 1888-1903).

Lin and colleagues found no studies that examined the benefit of thyroid cancer screening, although two studies showed that neck palpation was not sensitive for detecting thyroid nodules. The reviewers also noted that the combination of selected high-risk sonographic features was specific for thyroid malignancy in two methodologically limited studies.

As for harms, the reviewers found that three studies directly addressed the harms of thyroid cancer screening, but none suggested any serious harms from screening or ultrasound-guided fine-needle aspiration. However, no screening studies directly examined the risk for overdiagnosis, according to the group.

The researchers noted that two observational studies included patient cohorts treated for well-differentiated thyroid cancer as well as those with no surgery or surveillance. However, these studies didn't adjust for confounding factors and were therefore not designed to determine if patient outcome was improved by earlier or immediate treatment, according to the researchers.

Regarding treatment complications, the researchers found in 36 studies that the 95% confidence interval was 2.12 to 5.93 cases of permanent hypothyroidism per 100 thyroidectomies and 0.99 to 2.13 cases of recurrent laryngeal nerve palsy per 100 operations. Also, the reviewers said they found in 16 studies that treating differentiated thyroid cancer with radioactive iodine is associated with a small increase in the risk of second primary malignancies and with a higher risk of permanent adverse effects on the salivary gland, such as dry mouth.

"Although ultrasonography of the neck using high-risk sonographic characteristics plus follow-up cytology from fine-needle aspiration can identify thyroid cancers, it is unclear if population-based or targeted screening can decrease mortality rates or improve important patient health outcomes," the task force concluded. "Screening that results in the identification of indolent thyroid cancers, and treatment of these overdiagnosed cancers, may increase the risk of patient harms."

Opinions vary

In an editorial published online May 9 in JAMA: Otolaryngology -- Head and Neck Surgery, Dr. Louise Davies of the Veterans Affairs Medical Center in White River Junction, VT, and Dr. Luc Morris from Memorial Sloan Kettering Cancer Center in New York City said the USPSTF recommendation should discourage clinicians from screening for thyroid cancer with neck palpation, ultrasonography, or other techniques. They referred to the lack of evidence that detecting low-risk asymptomatic papillary thyroid cancer leads to a better outcome than just detecting and treating the cancer in symptomatic patients.

"In addition, given the prevalence of thyroid nodules and the typically slow growth trajectory of the most common form of thyroid cancer, screening programs will be associated with a clinically significant amount of harm," they wrote. "It is hoped that these recommendations will provide support in the United States for the development of monitoring programs for adults with small, incidentally identified cancers, with the ultimate goal of avoiding unnecessary treatments."

But perhaps overdiagnosis isn't to blame for the higher number of thyroid cancer diagnoses. In an editorial published online May 9 in JAMA Surgery, a team led by Dr. Julie Ann Sosa of Duke University Medical Center pointed to recent research that found an increase in overall thyroid cancer incidence over the past three decades, including higher incidence and mortality rates for advanced-stage papillary thyroid cancer.

What's more, overall incidence-based mortality also grew from 1994 to 2013 -- particularly for patients diagnosed with advanced-stage papillary thyroid cancer. These findings are consistent with a true increase in thyroid cancer occurrence in the U.S., and challenge the prevailing hypothesis that overdiagnosis is the sole culprit for this changing epidemiology, according to the group.

"These results suggest that a new focus should be placed on understanding alternative explanations for this increase other than overdiagnosis, including potentially modifiable factors, such as obesity and environmental exposures outside of the known influence of radiation," they wrote. "Furthermore, it would seem that additional energies and resources should be focused on supporting innovation and discovery around the management of locally advanced and metastatic thyroid cancer."

Nonetheless, the USPSTF recommendation may represent an opportunity to pause and recalibrate the collective approach to thyroid cancer screening, diagnosis, management, and surveillance, according to Sosa and colleagues.

"If the explanation for the rise in thyroid cancer is, indeed, not just overdiagnosis, and if mortality from thyroid cancer is also increasing, then enthusiasm for this (non)screening recommendation should be more muted," they wrote. "For clinicians and scientists working in the field of thyroidology, this is an interesting and compelling time. Clearly, more research is needed to identify alternative causes for the increasing incidence of the disease, to inform efforts at prevention, and to develop novel approaches to the management of advanced thyroid cancer."

Indeed, what the field needs is a noninvasive measure -- either radiographic or by biomarker -- to distinguish between nodules that have thyroid cells that will leave the capsule and cause morbidity and those that will not, said Dr. Anne Cappola of the University of Pennsylvania in an accompanying editorial in JAMA (May 9, 2017, Vol. 317:18, pp. 1840-1841).

"Using the same tools -- palpation, ultrasound imaging, and findings on microscopic examination -- is unlikely to result in a different conclusion about screening for thyroid cancer in the future," Cappola wrote. "New technologies are required."

RCC and Ultrasound

           ABSTRACT:

Ultrasound and Cystoscopy in Asymtomatic Hematuria

Should ultrasound replace CT for asymptomatic hematuria?

By Erik L. Ridley, AuntMinnie staff writer

April 18, 2017 -- The combination of renal ultrasound and cystoscopy is the most cost-effective strategy for evaluating patients with asymptomatic microscopic hematuria (AMH), potentially saving hundreds of millions of dollars compared with CT and cystoscopy, according to research published online April 17 in JAMA Internal Medicine.

US Elasto of LIVER: What the Clinician Needs to Know

DOWNLOAD FULLTEXT HERE 

PoCUS LUNG SONOGRAPHY

POCUS An Introduction
boyd.pdf

Abstract

Objectives

Point-of-care lung sonography has theoretical usefulness in numerous diseases; however clinical indications and the impact of this technique have not been fully investigated. We aimed to describe the current use of point-of-care lung sonography.

Methods

A 2-year prospective observational study was performed by pulmonologists in an Italian university hospital. Techniques, indications, consequences of lung sonography, and barriers to the examination were analyzed.

Results

A total of 1150 lung sonographic examinations were performed on 951 patients. The most common indications were diagnosis and follow-up of pleural effusion in 361 cases (31%), evaluation of lung consolidation (322 [28%]), acute heart failure (195 [17%]), guide to pleural procedures (117 [10%]), pneumothorax (54 [5%]) and acute exacerbations of chronic obstructive pulmonary disease (30 [3%]). The mean duration of the examination ± SD was 6 ± 4 minutes. The transducers most frequently used were convex (746 [65%]) and linear (161 [14%]), whereas in 205 examinations (18%), both transducers were used. According to the judgment of the caring clinician, 51% of the examinations were clinically relevant.

Conclusions

Point-of-care lung sonography performed by pulmonologists is quick and feasible and could be widely used for different clinical indications with a potentially high clinical impact. The widespread use of this technique may have a relevant clinical impact in several indications.

FOCAL THYROID LESIONS, a Review

DOWNLOAD FULLTEXT  focal thyroid lesions , a review

WFUMB 2017 TAIPEI: ABSTRACTS REGISTRATED from MEDIC

1. Checkered Appearance of Color Doppler in Diagnosing of Spontaneous Isolated Dissecting Aneurysm of the Superior Mesenteric Artery in Four Cases Tai Van Le, MD, Hai Thanh Phan, MD MEDIC Medical Center, HCM City, Vietnam Objectives: To describe ultrasound findings and role of color Doppler in diagnosing of spontaneous isolated dissecting aneurysm of the superior mesenteric artery. Methods: From 2015 – 2016, four cases were collected, male, age 48-60 years (mean age 53), diagnosis base on B-Mode and color Doppler which were confirmed by CT. All cases were in mild epigastric pain during scanning. There were three cases with acute onset epigastric pain sharply, relieve but not in recovery. In which the first case lasted one month, the second case lasted two months and the third case had acute epigastric pain for 2 days accompanied vomiting, dyspepsia and abdominal distension. Melena was noted in last case. Results: The dissecting aneurysm happens at proximal part and extending to distal part, bigger than 10 mm in diameter, with intimal flap inside to split into true and false lumen. The flapping of intimal flap is not very clear.  There were two cases with false lumens contain fully thrombosis. The checkered appearance of color Doppler images represented in three cases. Two cases were endovascular stenting, conservative therapy for one, and last case unknown final result. Conclusions: The checkered appearance of color Doppler images is typical pattern for diagnosing of dissecting aneurysm of superior mesenteric artery that can help in case of  not clear thin intimal flap.

2.  ACOUSTIC  RADIATION FORCE IMPULSE  IMAGING (ARFI)  of ULTRASOUND in ASSESSMENT  of PANCREAS DISORDERS

 Nguyen Thien Hung-Phan Thanh Hai.

MEDIC MEDICAL CENTER, HCMC, VIETNAM

ABSTRACT:

PURPOSE :

 To evaluate pancreas elastic characters  using ARFI technique in normal individuals, diabetic patients and patients in mild acute pancreatitis.

 MATERIAL and METHODS:

Using SIEMENS S2000 with VTI and VTQ techniques to evaluate pancreatic tissue [head, body and tail with 3 times measurements  for  each part of pancreas] . There were total of  30 normal individuals  (age 20-40), and 34 diabetic patients suffering  from  diabetes  for 2-10 years enrolled in this study.  Patients were fasting 8 hours before ultrasound examination and in half sitting position. Statistic and data were treated by MedCalc software.

 RESULTS and DISCUSSIONS:

Elastic mean velocity ARFI of normal pancreas from normal individuals was V1= 0.96+/-0.16 m/s (range 0.6-1.19m/s), and more faster [harder] in diabetic patients, V1= 1.32+/-0.18 m/s.  There was significant statistic difference of elastic velocity in 2 groups (p under 0.0001). In diabetic patients, diabetic tissue  is getting fibrosis for a determined time [2 years, 5 years  and 10 years] , while cystic masses  and acute pancreatitis  getting harder . ARFI techniques reveals pancreatic tissue harder in old patients and  suffering from diabetes  for years.

 CONCLUSION:

Using ARFI techniques in routine daily clinical activities could help evaluating elastic properties of pancreas in diabetes and pancreatic disorders. 

REFERENCES:

1/ Virtual analysis of pancreatic cystic lesion fluid content by ultrasound  ARFI Quantification, JUM

2013.

2/ Use ARFI Elastography to Diagnose Acute Pancreatitis at Hospital Admission, JUM 2014. 

Point of care ultrasound: A new tool for the 21st century nephrologist

Point of care ultrasound: A new tool for the 21st century nephrologist

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DANIEL W ROSS, MD, MPH; KENAR D. JHAVERI, MD; MANGALA NARASIMHAN, DO — APRIL 12, 2017

Abstract

There is an exciting change happening in nephrology training. Across the country, nephrology programs are bringing point of care ultrasound into their curricula. Nephrologists and nephrology trainees are not only using point of care ultrasound for the assessment of kidneys and bladder but also for volume assessment. In this article, we describe how our nephrology division designed a hands-on point of care ultrasound course for nephrology fellows. We also describe some important anecdotes from our experience that highlight the utility of this novel tool.

A new assessment tool for nephrologists

Across the country, nephrology fellows are being taught to use ultrasound at the point of care to make timely decisions about their patients.^{1 ,2} The movement to incorporate ultrasound training into nephrology dates back about a decade. In 2008, a survey of nephrology program directors found that some programs already offered training in diagnostic renal ultrasound and that 13% of programs planned to formally incorporate performance and interpretation of ultrasound into their curricula within a year.³ In a follow up survey in 2014, we found that most programs still did not have ultrasound training but that some programs offered two- or four-week rotations.⁴

Neither survey differentiated between ultrasound performed as a formal study and those performed at the bedside. In the last few years, ultrasound machines have become more portable and more affordable. Availability is increased as many emergency departments and ICUs house their own ultrasound machines. Therefore, opportunity exists for nephrologists to use ultrasound at the point of care to determine kidney size, measure bladder volume, assess for hydronephrosis, and even to evaluate volume status. Thus, the future of ultrasound training in nephrology may be in teaching-focused exams to answer discrete clinical questions rather than teaching complete examinations of the retroperitoneum and bladder.

At our institution, we are privileged to have international experts in point of care ultrasound in our critical care faculty. They have been instrumental in popularizing and promoting a whole-body approach to point of care ultrasound (POCUS). Each year they give several three-day courses for the American College of Chest Physicians as well as a course for incoming pulmonary and critical care fellows. They have done a substantial amount of educational research and have refined their technique over time.⁵ In the last decade, this teaching faculty at Hofstra-Northwell School of Medicine have instructed more than 15,000 trainees and have organized a focused course for our nephrology division.⁶

A significant portion of the course focused on using lung ultrasound to assess volume status. Lung ultrasound has the potential to be a revolutionary, paradigm-shifting tool for leading-edge nephrologists (see sidebar).

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How a lung ultrasound can help measure volume

Over the last two decades, intensivist Daniel Lichtenstein has demonstrated that when an ultrasound beam hits the surface of a normal lung, it generates artifacts called an “A line.” When an ultrasound beam hits a lung filled with water, it generates a reverberation artifact that juts away like a bright white rocket. These lung rockets are called “B lines.”⁷  A lines and B lines are shown in Figure 1. Research has shown that B Lines correlate with gold standards of volume assessment.

Figure 1. A lines (left image) are horizontal artifacts that appear parallel to the pleural line and indicate a normally aerated lung. B lines (right image) are reverberation artifacts generated by water-thickened interlobular septa and represent pulmonary edema in the appropriate clinic setting.

For nephrologists who are unfamiliar with lung ultrasound, there are three “need to know” points. First, B lines are a reliable method for determining volume status in dialysis patients. Second, a higher number of B lines in these patients correlates with greater mortality. Third, lung ultrasound is teachable and takes less than ten minutes to perform.

Since our initial training course in 2015 and subsequent refresher course in 2016, our division has started to incorporate point of care ultrasound into clinical practice. In one illustrative example, we were faced with an elderly woman with chronic kidney disease who was admitted with an acute exacerbation of congestive heart failure. In the setting of diuresis, the patient’s creatinine rose and she developed acute kidney injury. Her volume status became difficult to discern by traditional physical examination and we were concerned that we had gone too far with the diuretics. Emboldened by our newly acquired skills, we performed a lung ultrasound. We found that the patient had a diffuse B line pattern consistent with pulmonary edema––not seen on chest x ray or appreciated on lung auscultation. Diuretics were increased and the patient’s creatinine improved back to baseline as her heart failure resolved.

In another example, we used focused renal ultrasound to assess an elevated creatinine in a patient being considered for a left ventricular assist device (LVAD). In these patients, it is of paramount importance to identify whether the patient’s kidneys are intrinsically normal. At the time we evaluated this patient we did a point of care ultrasound examination. The kidneys were normal in size and had normal cortical thickness, there was no hydronephrosis, and the patient’s bladder was collapsed around the indwelling urethral catheter. This timely information, in conjunction with a bland urine sediment and a low urine sodium, enabled us to confidently identify the patient’s heart failure as the cause of his kidney injury. Ultimately the patient’s creatinine returned to normal two days after LVAD placement.

The value of being able to rapidly discover urinary obstruction is immeasurable. A patient presented to our outpatient clinic for evaluation of an elevated creatinine. Based upon history, obstruction was suspected. A quick look at the patient’s bladder post void proved the case. The patient was referred to a same day urology appointment where an indwelling urethral catheter was placed. In this case, hospitalization was averted and a brewing renal injury was recognized early.

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