3D CT Soft Tissue Craniofacial Analysis and Lip Morphology

ABSTRACT Objctive: To assess the soft tissue characteristics of Bangladeshi adults to formulate soft tissue 3D CT standards using Holdaway's (HA) and lip morphology (LM) analyses. Another aim of this study was to assess the gender dimorphism of Bangladeshi population. Material and Methods: One hundred and seventeen (Eighty-five men and Thirty-two women) Bangladeshi adults have obtained their computed tomography (CT) scan at the Radiology Department for normal diagnosis. Craniofacial deformities were undetected in all cases. The CT images were prepared by a 3D imaging programming software (Mimics 11.02 Materialise). Parameters from the identified landmark points were measured in 3D through this software. Results: Upper lip thickness (ULT) (vermillion UL-A point) measurement was significant in HA and in LM analyses, upper lip protrusion (ULP) (Ls to Sn-SPog) measurement has demonstrated significant difference among both genders, where p-value was less than 0.05. Mean measurements of Bangladeshi adults were relatively comparable except the face convexity (FC) when compared with the HA cephalometric soft tissue values. Conclusion: By using HA and LM analyses, 3D CT soft tissue standards were established for Bangladeshi adults. Measurements for all parameters have remained equivalent with the HA standard data apart from the FC measurement. This consequently may demonstrate that the Bangladeshi population retains a convex shape with a slight protrusive lip or retruded chin.

Measurement of Lumbar Lordosis: A Comparison of 2 Alternatives to the Cobb Angle.

OBJECTIVE: The purpose of this study was to compare 2 alternative methods, the radiologic Harrison Posterior Tangent Method (HPTM) and the nonradiologic Spinal Mouse (SM), to the Cobb angle for measuring lumbar lordosis. METHODS: Sixteen participants with previously existing lateral lumbopelvic radiographs underwent nonradiographic lordosis assessment with a Spinal Mouse. Then 2 investigators analyzed each radiograph twice using the Harrison Posterior Tangent Method and Cobb angle. Correlations were analyzed between HPTM, the Cobb angle, and SM using the Spearman rank correlation coefficient; intraexaminer and interexaminer agreement were analyzed for HPTM and the Cobb angle using intraclass correlation coefficients. RESULTS: The HPTM correlated highly with the Cobb angle (Spearman ρ = 0.936, P < .001); SM had moderate to strong correlations with the Cobb angle (ρ = 0.737, P = .002) and HPTM (ρ = 0.707, P = .003). Intraexaminer and interexaminer agreement for the Cobb angle and HPTM were excellent (all intraclass correlation coefficients > 0.90). One participant had slight kyphosis according to HPTM and SM analyses (which consider the entire lumbar region), whereas the Cobb angle, based only on L1 and L5, reported mild lordosis for that participant. CONCLUSION: In this sample, HPTM measurements showed high correlation with the commonly used Cobb angle, but this method requires more time and effort, and normal values have not been established. The SM may be an alternative when radiographs are inappropriate, but it measures soft tissue contours rather than lordosis itself.

Using magnetic particle imaging systems to localize and guide magnetic hyperthermia treatment: tracers, hardware, and future medical applications.

Magnetic fluid hyperthermia (MFH) treatment makes use of a suspension of superparamagnetic iron oxide nanoparticles, administered systemically or locally, in combination with an externally applied alternating magnetic field, to ablate target tissue by generating heat through a process called induction. The heat generated above the mammalian euthermic temperature of 37°C induces apoptotic cell death and/or enhances the susceptibility of the target tissue to other therapies such as radiation and chemotherapy. While most hyperthermia techniques currently in development are targeted towards cancer treatment, hyperthermia is also used to treat restenosis, to remove plaques, to ablate nerves and to alleviate pain by increasing regional blood flow. While RF hyperthermia can be directed invasively towards the site of treatment, non-invasive localization of heat through induction is challenging. In this review, we discuss recent progress in the field of RF magnetic fluid hyperthermia and introduce a new diagnostic imaging modality called magnetic particle imaging that allows for a focused theranostic approach encompassing treatment planning, treatment monitoring and spatially localized inductive heating.

Diagnosis and management of surgical disease at Ethiopian health centres: cross-sectional survey of resources and barriers to care.

OBJECTIVES: The aim of this study was to characterise the resources and challenges for surgical care and referrals at health centres (HCs) in South Wollo Zone, Ethiopia. SETTING: Eight primary HCs in South Wollo Zone, Ethiopia. PARTICIPANTS: Eight health officers and nurses staffing eight HCs completed a survey. DESIGN: The study was a survey-based, cross-sectional assessment of HCs in South Wollo Zone, Ethiopia and data were collected over a 30-day period from November 2014 to January 2015. PRIMARY AND SECONDARY OUTCOME MEASURES: Survey assessed human and material resources, diagnostic capabilities and challenges and patient-reported barriers to care. RESULTS: Eight HCs had an average of 18 providers each, the majority of which were nurses (62.2%) and health officers (20.7%). HCs had intermittent availability of clean water, nasogastric tubes, rectal tubes and suturing materials, none of them had any form of imaging. A total of 168 surgical patients were seen at the 8 HCs; 58% were referred for surgery. Most common diagnoses were trauma/burns (42%) and need for caesarean section (9%). Of those who did not receive surgery, 32 patients reported specific barriers to obtaining care (91.4%). The most common specific barriers were patients not being decision makers to have surgery, lack of family/social support and inability to afford hospital fees. CONCLUSIONS: HCs in South Wollo Zone, Ethiopia are well-staffed with nurses and health officers, however they face a number of diagnostic and treatment challenges due to lack of material resources. Many patients requiring surgery receive initial diagnosis and care at HCs; sociocultural and financial factors commonly prohibit these patients from receiving surgery. Further study is needed to determine how such delays may impact patient outcomes. Improving material resources at HCs and exploring community and family perceptions of surgery may enable more streamlined access to surgical care and prevent delays.

Magnetic nanocarriers: Evolution of spinel ferrites for medical applications.

A valuable site-directed application in the field of nanomedicine is targeted drug delivery using magnetic metal oxide nanoparticles by applying an external magnetic field at the target tissue. The magnetic property of these structures allows controlling the orientation and location of particles by changing the direction of the applied external magnetic field. Pharmaceutical design and research in the field of nanotechnology offer novel solutions for diagnosis and therapies. This review summarizes magnetic nanoparticles and magnetic spinel ferrit's properties, remarkable approaches in magnetic liposomes, magnetic polymeric nanoparticles, MRI, hyperthermia and especially magnetic drug delivery systems, which have recently developed in the field of magnetic nanoparticles and their medicinal applications. Here, we discuss spinel ferrite (SF) as magnetic materials that are a significant class of composite metal oxides. They contain ferric ions and have the general structural formula M2+Fe23+O4 (where M = Co,Ni,Zn,etc.). This structure indicates unique multifunctional properties, such as excellent magnetic characteristics, high specific surface area, surface active sites, high chemical stability, tuneable shape and size, and options for functionalization. The review assesses the current efforts on synthesis, properties and medical application of magnetic spinel ferrites nanoparticles based on cobalt, nickel and zinc. Based on this review, it can be concluded that MNPs and SFNPs have unlimited ability in biomedical applications. However, the practical application of SFNPs on a huge scale still needs to be considered and evaluated.

Computational phantom study of frozen melanoma imaging at 0.45 terahertz.

Terahertz radiation (THz) is highly absorbed by liquid water. This creates the possibility of medical imaging on the basis of the water content difference between normal and diseased tissue. The effective penetration of THz is limited, however, to a tissue depth of 0.2-0.3 mm at body temperature. A unique feature of the 0.1-2.0 THz frequency is that there is a high disparity between liquid water absorption and ice absorption, with ice being 100 times more permeable to the radiation than liquid water. This results in 90% of the radiation surviving to 1.0 mm in ice, permitting the imaging of frozen tissues to a depth of 5.0 mm. This method is practical as an in vivo procedure before or during surgical excision. Finite difference time domain (FDTD) computational modeling of frozen normal skin and frozen melanoma was undertaken using tissue phantoms. The study suggests that sufficient contrast exists to differentiate normal frozen skin and melanoma on the basis of the difference of water content alone. When the melanin pigment in melanomas is modeled as a significant absorber of THz, the contrast changes. Based on the modeling, further exploration of the "THz-skin freeze" imaging technique is justified. In the modeling, the boundary between the frozen tissue and non-frozen tissue is shown to be strongly reflective. If the reflective properties of the boundary are substantiated, the "THz-skin freeze" technique will have applications in other areas of skin diagnostics and therapeutics. Bioelectromagnetics. 40:118-127, 2019. © 2019 Bioelectromagnetics Society.

SEOM/SERAM consensus statement on radiological diagnosis, response assessment and follow-up in colorectal cancer

Colorectal cancer (CRC) is one of the world’s most common cancers, and has one of the highest mortality rates. The last few decades have seen great progress in preventing, diagnosing and treating this disease, providing undeniable impact on patients’ prognosis and quality of life. At all these stages of CRC management, imaging techniques play an essential role. This article reviews some important issues concerning the use of various radiological techniques in the screening, diagnosis, staging, assessment of treatment response, and follow-up of patients with CRC. It also includes a number of practical recommendations on indications for use, technical requirements, minimum information required in the radiology report, evaluation criteria for the response to various drugs, and the recommended frequency at which different examinations should be performed. This consensus statement is the result of cooperation between the Spanish Society of Medical Oncology (SEOM) and the Spanish Society of Radiology (SERAM) (AU)

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Increased yield pressure in the anal canal during sacral nerve stimulation: a pilot study with the functional lumen imaging probe.

BACKGROUND: Sacral nerve stimulation (SNS) is a well-established treatment for fecal incontinence but its mode of action remains obscure. Anal sphincter function is usually evaluated with manometry but resistance to distension may be a more appropriate parameter than luminal pressure. The functional lumen imaging probe allows detailed description of distension properties of the anal canal. Our objective in this study was to characterize the impact of SNS on distension properties of the anal canal in patients with idiopathic fecal incontinence. METHODS: We studied 10 women (median age 64 [44-79] years) with idiopathic fecal incontinence at baseline and during SNS. The luminal geometry of the anal canal was examined with the FLIP at rest and during squeeze and the distensibility of the anal canal was investigated during filling of the bag. KEY RESULTS: All patients were successfully treated with SNS and the mean Wexner Incontinence Score was reduced from 14.9 ± 4 to 7.1 ± 4.8 (P<.001). The pressure required to open the narrowest point of the anal canal during distension (yield pressure) increased from 14.5 ± 12.2 mmHg at baseline to 20.5 ± 13.3 mmHg during SNS (P<.01). The pressure-strain elastic modulus increased non-significantly from 2.2 ± 0.5 to 2.9 ± 1.6 kPa, indicating increased stiffness of the anal canal. CONCLUSION AND INFERENCES: The yield pressure and the resistance to distension increased in response to SNS for idiopathic fecal incontinence. This will inevitably increase the resistance to flow through the anal canal, which may contribute to the benefits of sacral nerve stimulation.

A Distinguishing Arterial Pulse Waves Approach by Using Image Processing and Feature Extraction Technique.

Traditional Chinese Medicine (TCM) is based on five main types of diagnoses methods consisting of inspection, auscultation, olfaction, inquiry, and palpation. The most important one is palpation also called pulse diagnosis which is to measure wrist artery pulse by doctor's fingers for detecting patient's health state. In this paper, it is carried out by using a specialized pulse measuring instrument to classify one's pulse type. The measured pulse waves (MPWs) were segmented into the arterial pulse wave curve (APWC) by image proposing method. The slopes and periods among four specific points on the APWC were taken to be the pulse features. Three algorithms are proposed in this paper, which could extract these features from the APWCs and compared their differences between each of them to the average feature matrix, individually. These results show that the method proposed in this study is superior and more accurate than the previous studies. The proposed method could significantly save doctors a large amount of time, increase accuracy and decrease data volume.

Ecografía mamaria complementaria a la mamografía de cribado / Ultrasound as a complementary tool to screening mammography

La mamografía es la técnica habitual para el cribado poblacional del cáncer de mama. Sin embargo, la sensibilidad mamográfica disminuye mucho en las mamas densas, pudiendo ser de tan solo el 50%. En estos casos la ecografía complementaria puede jugar un papel importante al mejorar la sensibilidad, llegando a tasas de detección de cáncer de hasta el 0,3%. Sin embargo, la ecografía disminuye la especificidad y aumenta la tasa de rellamadas y de biopsias. La ecografía manual es operador dependiente, obliga a emplear mucho tiempo de radiólogo y no permite una revisión retrospectiva. La ecografía automatizada permite solventar varias de estas limitaciones, por lo que puede llegar a emplearse en el cribado como técnica adicional a la mamografía, especialmente en el caso de las mamas densas (AU)

Mammography is routinely used for population-based breast cancer screening. However, the sensitivity of mammography is greatly reduced in dense breasts, and can be as low as 50%. In these cases, complementary ultrasound can play an important role in improving sensitivity, achieving cancer detection rates of up to 0.3%. Nevertheless, ultrasound reduces specificity and increases recall and biopsy rates. Manual ultrasound is operator dependent, is time consuming for the radiologist and does not allow a retrospective review. Automated ultrasound resolves several of these limitations and consequently could become used as an additional technique to mammography, especially in women with dense breasts (AU)

BrachyView, a novel in-body imaging system for HDR prostate brachytherapy: Experimental evaluation.

PURPOSE: This paper presents initial experimental results from a prototype of high dose rate (HDR) BrachyView, a novel in-body source tracking system for HDR brachytherapy based on a multipinhole tungsten collimator and a high resolution pixellated silicon detector array. The probe and its associated position estimation algorithms are validated and a comprehensive evaluation of the accuracy of its position estimation capabilities is presented. METHODS: The HDR brachytherapy source is moved through a sequence of positions in a prostate phantom, for various displacements in x, y, and z. For each position, multiple image acquisitions are performed, and source positions are reconstructed. Error estimates in each dimension are calculated at each source position and combined to calculate overall positioning errors. Gafchromic film is used to validate the accuracy of source placement within the phantom. RESULTS: More than 90% of evaluated source positions were estimated with an error of less than one millimeter, with the worst-case error being 1.3 mm. Experimental results were in close agreement with previously published Monte Carlo simulation results. CONCLUSIONS: The prototype of HDR BrachyView demonstrates a satisfactory level of accuracy in its source position estimation, and additional improvements are achievable with further refinement of HDR BrachyView's image processing algorithms.

Development of solid-state avalanche amorphous selenium for medical imaging.

PURPOSE: Active matrix flat panel imagers (AMFPI) have limited performance in low dose applications due to the electronic noise of the thin film transistor (TFT) array. A uniform layer of avalanche amorphous selenium (a-Se) called high gain avalanche rushing photoconductor (HARP) allows for signal amplification prior to readout from the TFT array, largely eliminating the effects of the electronic noise. The authors report preliminary avalanche gain measurements from the first HARP structure developed for direct deposition onto a TFT array. METHODS: The HARP structure is fabricated on a glass substrate in the form of p-i-n, i.e., the electron blocking layer (p) followed by an intrinsic (i) a-Se layer and finally the hole blocking layer (n). All deposition procedures are scalable to large area detectors. Integrated charge is measured from pulsed optical excitation incident on the top electrode (as would in an indirect AMFPI) under continuous high voltage bias. Avalanche gain measurements were obtained from samples fabricated simultaneously at different locations in the evaporator to evaluate performance uniformity across large area. RESULTS: An avalanche gain of up to 80 was obtained, which showed field dependence consistent with previous measurements from n-i-p HARP structures established for vacuum tubes. Measurements from multiple samples demonstrate the spatial uniformity of performance using large area deposition methods. Finally, the results were highly reproducible during the time course of the entire study. CONCLUSIONS: We present promising avalanche gain measurement results from a novel HARP structure that can be deposited onto a TFT array. This is a crucial step toward the practical feasibility of AMFPI with avalanche gain, enabling quantum noise limited performance down to a single x-ray photon per pixel.

Active multispectral imaging system for photodiagnosis and personalized phototherapies.

The proposed system has been designed to identify dermatopathologies or to apply personalized phototherapy treatments. The system emits electromagnetic waves in different spectral bands in the range of visible and near infrared to irradiate the target (skin or any other object) to be spectrally characterized. Then, an imaging sensor measures the target response to the stimulus at each spectral band and, after processing, the system displays in real time two images. In one of them the value of each pixel corresponds to the more reflected wavenumber whereas in the other image the pixel value represents the energy absorbed at each band. The diagnosis capability of this system lies in its multispectral design, and the phototherapy treatments are adapted to the patient and his lesion by measuring his absorption capability. This "in situ" absorption measurement allows us to determine the more appropriate duration of the treatment according to the wavelength and recommended dose. The main advantages of this system are its low cost, it does not have moving parts or complex mechanisms, it works in real time, and it is easy to handle. For these reasons its widespread use in dermatologist consultation would facilitate the work of the dermatologist and would improve the efficiency of diagnosis and treatment. In fact the prototype has already been successfully applied to pathologies such as carcinomas, melanomas, keratosis, and nevi.

Mesoscopic reflectance angular domain spectroscopic imaging.

The advancement of angular domain imaging in mesoscopic reflectance multispectral imaging is reported. The key component is an angular filter array that performs the angular filtration of the back-scattered photons and generates image contrast due to the variances in tissue optical properties. The proposed modality enables multispectral imaging of subsurface features for samples too thick for transillumination angular domain spectroscopic imaging (ADSI) approaches. The validation was carried out with tissue-mimicking phantoms with multiple absorptive features embedded below the surface. Multispectral images in the range of 666 to 888 nm clearly revealed the location of the features with the background scattering levels up to 20 cm⁻¹. The shape of the features was recoverable at depths of up to three to four times the transport mean free path. The spatial resolution was <1 mm and the field-of-view was larger than 2.5 cm x 30. cm. Furthermore, the attenuation spectra of measured absorptive features were successfully extracted. Target detectability and imaging quality with different background scattering levels, target depths, and illumination focal depths were discussed, as well as the capability of ADSI in reflectance optical mesoscopic imaging and its potential applications.

Considerations for conducting imaging studies in support of developmental toxicology studies for regulatory submission.

Preclinical imaging technologies are increasingly being applied to developmental toxicology studies in drug development to determine potential compound toxicity. Although most of these studies are conducted in a non-regulatory setting, there is interest in performing these imaging studies under applicable regulations, for example Good Laboratory Practices (GLP), to support regulatory decisions concerning drug safety. This manuscript will describe regulations and processes to consider when bringing an imaging technology into GLP compliance.

Role of contrast and fractality of laser speckle image in assessing flow velocity and scatterer concentration in phantom body fluids.

Blood flow velocity and red blood cell concentration are of vital importance in assessing tissue microcirculation. Laser speckle contrast analysis is being considered as a promising tool in the qualitative assessment of flow velocity as well as scatterer concentration in different body fluids, though the quantification part still remains challenging. The fractal-based spatial correlation analysis of speckle flow images along with the corresponding contrast analysis for the quantitative assessment of flow and scatterer concentration is investigated. In this study, phantom body fluid solution (intralipid 20%) of different concentrations is pumped at different flow rates through the designed flow channel using a syringe pump and the corresponding speckle images are acquired. The fractality of the acquired speckle images in response to the changes in concentration of the fluid as well as the variations in fluid flow is analyzed along with the corresponding contrast-based analysis. Following this qualitative analysis, an experimental model is attempted toward quantification of these parameters from a single acquired speckle image by considering the contrast and fractality changes together.

Mobile Health (mHealth) biomedical imaging paradigm.

Technology assisted methods for medical diagnosis and biomedical health monitoring are rapidly shifting from classical invasive methods to handheld-based non-invasive approaches. Biomedical imagining is one of the most prominent practices of non-invasive mechanisms in medical applications. This paper considers the medical imaging schemes for Mobile Health (mHealth) applications and studies the feasibility of future mobile systems for accommodating image informatics capabilities.

Demonstration of electron acceleration in a laser-driven dielectric microstructure.

The enormous size and cost of current state-of-the-art accelerators based on conventional radio-frequency technology has spawned great interest in the development of new acceleration concepts that are more compact and economical. Micro-fabricated dielectric laser accelerators (DLAs) are an attractive approach, because such dielectric microstructures can support accelerating fields one to two orders of magnitude higher than can radio-frequency cavity-based accelerators. DLAs use commercial lasers as a power source, which are smaller and less expensive than the radio-frequency klystrons that power today's accelerators. In addition, DLAs are fabricated via low-cost, lithographic techniques that can be used for mass production. However, despite several DLA structures having been proposed recently, no successful demonstration of acceleration in these structures has so far been shown. Here we report high-gradient (beyond 250 MeV m(-1)) acceleration of electrons in a DLA. Relativistic (60-MeV) electrons are energy-modulated over 563 ± 104 optical periods of a fused silica grating structure, powered by a 800-nm-wavelength mode-locked Ti:sapphire laser. The observed results are in agreement with analytical models and electrodynamic simulations. By comparison, conventional modern linear accelerators operate at gradients of 10-30 MeV m(-1), and the first linear radio-frequency cavity accelerator was ten radio-frequency periods (one metre) long with a gradient of approximately 1.6 MeV m(-1) (ref. 5). Our results set the stage for the development of future multi-staged DLA devices composed of integrated on-chip systems. This would enable compact table-top accelerators on the MeV-GeV (10(6)-10(9) eV) scale for security scanners and medical therapy, university-scale X-ray light sources for biological and materials research, and portable medical imaging devices, and would substantially reduce the size and cost of a future collider on the multi-TeV (10(12) eV) scale.

[Hybrid operating rooms: only for advanced endovascular procedures?]. / Angio-Hybrid-Operationsraum: Grundvoraussetzung nur für komplexe endovaskuläre Eingriffe?

The evolution of endovascular techniques has led to the concept of the "hybrid operating room" (hybrid OR). A hybrid OR combines the sterility of an OR in an operating theatre environment with a high-quality fixed imaging system. On the basis of these advantages it would be desirable that an angio-hybrid OR becomes a standard requirement for endovascular surgery. In Great Britain guidelines have already been published that require a hybrid OR even for normal endovascular management of the infrarenal aorta. However, in Germany there are no guidelines from professional societies or formal rules from the federal joint committee, thus in this article a classification of endovascular procedures according to their complexity and the necessary infrastructures are proposed in order to define particular procedures that should only be performed in an angio-hybrid OR. According to our experience, endovascular procedures can be classified into four categories based on their complexity and the requirements regarding fluoroscopy: level 1: standard EVAR, TEVAR, iliac and popliteal artery procedures; level 2: iliac branched (IBD) and standard (2 fenestrations for the renal arteries and a scallop for the superior mesenteric artery) fenestrated stent-grafting; level 3: more complex fenestrated procedures (three or four fenestrations); and level 4: branched stent-grafting for TAAA. At this moment it is still acceptable to perform level 1 and level 2 procedures outside of a hybrid OR. In our opinion, it is not recommended to perform level 3 and level 4 endovascular procedures without a hybrid OR.