Automatic segmentation of coronary lumen and external elastic membrane in intravascular ultrasound images using 8-layer U-Net.

BACKGROUND: Intravascular ultrasound (IVUS) is the golden standard in accessing the coronary lesions, stenosis, and atherosclerosis plaques. In this paper, a fully automatic approach by an 8-layer U-Net is developed to segment the coronary artery lumen and the area bounded by external elastic membrane (EEM), i.e., cross-sectional area (EEM-CSA). The database comprises single-vendor and single-frequency IVUS data. Particularly, the proposed data augmentation of MeshGrid combined with flip and rotation operations is implemented, improving the model performance without pre- or post-processing of the raw IVUS images. RESULTS: The mean intersection of union (MIoU) of 0.937 and 0.804 for the lumen and EEM-CSA, respectively, were achieved, which exceeded the manual labeling accuracy of the clinician. CONCLUSION: The accuracy shown by the proposed method is sufficient for subsequent reconstruction of 3D-IVUS images, which is essential for doctors' diagnosis in the tissue characterization of coronary artery walls and plaque compositions, qualitatively and quantitatively.

Segmentation of finger tendon and synovial sheath in ultrasound image using deep convolutional neural network.

BACKGROUND: Trigger finger is a common hand disease, which is caused by a mismatch in diameter between the tendon and the pulley. Ultrasound images are typically used to diagnose this disease, which are also used to guide surgical treatment. However, background noise and unclear tissue boundaries in the images increase the difficulty of the process. To overcome these problems, a computer-aided tool for the identification of finger tissue is needed. RESULTS: Two datasets were used for evaluation: one comprised different cases of individual images and another consisting of eight groups of continuous images. Regarding result similarity and contour smoothness, our proposed deeply supervised dilated fully convolutional DenseNet (D2FC-DN) is better than ATASM (the state-of-art segmentation method) and representative CNN methods. As a practical application, our proposed method can be used to build a tendon and synovial sheath model that can be used in a training system for ultrasound-guided trigger finger surgery. CONCLUSION: We proposed a D2FC-DN for finger tendon and synovial sheath segmentation in ultrasound images. The segmentation results were remarkably accurate for two datasets. It can be applied to assist the diagnosis of trigger finger by highlighting the tissues and generate models for surgical training systems in the future. METHODS: We propose a novel finger tendon segmentation method for use with ultrasound images that can also be used for synovial sheath segmentation that yields a more complete description for analysis. In this study, a hybrid of effective convolutional neural network techniques are applied, resulting in a deeply supervised dilated fully convolutional DenseNet (D2FC-DN), which displayed excellent segmentation performance on the tendon and synovial sheath.

Clinical and Radiological Evaluation of Sinus Membrane Osteogenicity Subsequent to Internal Sinus Lifting and Implant Placement.

To evaluate the ability of the maxillary sinus membrane to produce bone after internal sinus lifting and implant placement without adding exogenous bone graft, and to assess the quality of bone that has been produced 6 months postoperatively.In this retrospective study, 10 subjects who underwent maxillary sinus floor lifting and met the inclusion criteria were selected and then subdivided into: Group-A underwent internal sinus elevation and placement of implants without the use of bone graft and Group-B underwent classical internal sinus lifting and placement of bovine bone particles and then placement of the implant as a control group. Radiofrequency analysis (RFA) values for measuring the Implant Stability Quotient (ISQ) of all implants were measured by Osstell device. CBCT was performed involving linear measurements of the site of sinus lifting for both groups.High RFA values demonstrating excellent biomechanical stability were observed in Group-A compared to Group-B at 6 months postoperatively. Group-A showed a median of ISQ value;78 (8), 77(12), 79(3.5) and 77(4.50). Group-A was significantly higher in ISQ values than Group-B, which showed median and interquartile range (IQR) of ISQ value of [51(12.50), 54(14.50), 55(9), and 55(7.50)]. However, the amount of bone available in group B was significantly higher than group A; [3.5 mm (0.75) and 3.8 mm (0.69)].Internal sinus lifting without bone graft has the ability of bone formation by osteogenic potential of the sinus membrane. Nevertheless, the high quality of bone being produced is of high importance for the success of an implant without the need for an exogenous bone graft. The newly formed bone was significantly of a better quality in Group-A. Thus, it is recommended to perform internal sinus lifting, without adding bone graft material and allow the osteogenic potential of the maxillary sinus membrane to produce its own osteogenic cells.

Corpus cavernosum thrombosis: The membrane may play its role.

Partial thrombosis of corpus cavernosum is an uncommon condition that needs a high level of suspicious to be diagnosed. Imaging techniques may be very useful, and MR is the state-of-the-art technique. We present a case of a young male who presented to the emergency department with perineal and painful mass. MR imaging clearly depicted a thrombosed corpus cavernosum and a bilateral membrane that is possibly the underlying predisposing condition. With only conservative treatment the patient had an excellent outcome.

Ultrasonographic identification of the cricothyroid membrane in a patient with a difficult airway as a result of cervical hematoma caused by hemophilia: a case report.

BACKGROUND: Surgical cricothyroidotomy is a last resort in patients with an anticipated difficult airway, but without any guarantee of success. Identification of the cricothyroid membrane may be the key to successful cricothyrotomy. Ultrasonographic identification of the cricothyroid membrane has been reported to be more useful than the conventional palpation technique. However, ultrasonographic identification techniques are not yet fully characterized. CASE PRESENTATION: A 28-year-old man with hemophilia and poor adherence to medication. He was brought to the emergency department with a large cervical hematoma and respiratory difficulty. An otolaryngologist decided to insert a tracheal tube to maintain his airway. However, emergent laryngoscopy indicated an anticipated difficult airway. A backup plan that included awake intubation by the anesthesiologists and surgical cricothyroidotomy by an otolaryngologist was devised. The cricothyroid membrane could not be identified by palpation but was detected by ultrasonographic identification with a longitudinal approach. Awake fiberoptic intubation was successfully performed. CONCLUSIONS: In this case, the cricothyroid membrane could be identified using the longitudinal approach but not the transverse approach. It may be ideal to know which ultrasound technique can be applied for each patient.

First comparative results about the direct effect of traditional cigarette and e-cigarette smoking on lung alveolocapillary membrane using dynamic ventilation scintigraphy.

INTRODUCTION: Dynamic inhalation scintigraphy (DIS) with technetium-99m-diethylenetriamine-pentaacetate aerosol is a useful nuclear medicine procedure for staging and monitoring the damage of alveolocapillary membrane. The e-cigarette is a new popular smoking device producing vapor from the nicotine solution. Many studies have shown that e-cigarettes appear to be safer than smoking, but there are still debates to what extent e-cigarettes are less harmful than smoking.In this prospective, self-controlled study, we compared DIS results among volunteers smoking an e-cigarette and their results after they returned to traditional cigarette smoking for a week. PARTICIPANTS AND METHODS: We included 24 healthy volunteers into this study who regularly used e-cigarette containing at least 10 mg nicotine/ml. We performed baseline DIS study in volunteers with e-cigarette smoking and then we asked them to return to traditional cigarette smoking for a week. Conventional respiration tests were also measured. We statistically analyzed the effect of traditional cigarette on clinical parameters and pulmonary clearance of the radiopharmacon. RESULTS: There was no significant change in the parameters of peak expiratory flow rate and Tiffeneau-Pinelli index respiration tests; forced vital capacity and forced expiratory volume in 1 s slightly decreased (P<0.05), whereas the exhaled CO and COHb levels were significantly higher at traditional cigarette use (P<0.0001), and increased in every case. The pulmonary clearance was significantly faster at traditional cigarette smoking compared with e-cigarette use (P<0.0001). CONCLUSION: On the basis of our results, we suppose that e-cigarette smoking is less harmful to the lung function than a traditional cigarette, and it can be recommended to heavy smokers who are unable to stop smoking.

Ultrasound for identifying the cricothyroid membrane prior to the anticipated difficult airway.

BACKGROUND: Prior to the anticipated difficult airway, the emergency physician commonly palpates the neck to identify the presumed location of the cricothyroid membrane (CTM). In the event of a "cannot-intubate, cannot­oxygenate" airway, precise CTM localization is vital to the success of a cricothyrotomy and hence, the patient's survival. OBJECTIVE: This narrative review will summarize the prospective studies evaluating CTM identification. It will demonstrate the inaccuracy of the classically used landmark palpation technique. It will then describe the use of ultrasound (US) as a superior tool for CTM identification, illustrate the technique itself, and propose its implementation in the pre-intubation checklist for the anticipated difficult airway. DISCUSSION: Evidence demonstrates that physicians are not sufficiently accurate in palpating the CTM in both cadavers and volunteers in a stable non-emergent setting. In preparing for a real-time intubation, this fine motor task would be more difficult to achieve. Moreover, this particular patient group may often exhibit difficult airway features. US has been demonstrated to be superior for locating the CTM than landmark palpation across body habitus, gender, and failed airway simulations. This technique carries a short learning curve even without prior airway US experience, along with a high retention rate. An illustrative tutorial is provided. CONCLUSION: Emergency physicians may apply this US technique for CTM localization in preparation for an anticipated difficult airway. However, since this technique takes longer than landmark palpation, using US is not recommended once already in the midst of a failed airway situation.

Análogos de prostaglandinas y desarrollo de membrana epirretinal / Topical prostaglandin analogues and development of epiretinal membrane

OBJETIVOS: Evaluar la posible asociación entre el uso de análogos de prostaglandinas (AP) y el desarrollo de membrana epirretinal (MER) en pacientes con glaucoma. MÉTODO: Mediante el método comparativo se realizó un diseño retrospectivo de casos y controles. Se compararon pacientes que presentaban glaucoma y, a su vez, MER y que utilizaban una mayor proporción de AP con un grupo control de pacientes que presentaban glaucoma pero sin MER. El diagnóstico de MER ha sido realizado mediante un examen clínico y un estudio de tomografía de coherencia óptica. RESULTADOS: La edad media de los casos ha sido de 77 años, con DE de 8,68 (IC 95%: 74,3-79,4) y la de los controles de 63 años, con DE de 16,6 (IC 95%: 70,1-78,5). El 50% de los casos (n = 26) estaba compuesto por hombres y el otro 50% eran mujeres (n = 26), mientras que para los controles el 25,4% eran hombres (n = 16) y el 74,6% eran mujeres (n = 47). El 59,6% de los casos (n = 31) y el 60,3% de los controles (n = 38) fueron tratados con AP. No se ha observado ninguna diferencia de colocación de AP entre ambos grupos (p = 0,939). CONCLUSIONES: En este trabajo no hemos podido demostrar si existe asociación entre el uso de AP y el desarrollo de MER

OBJECTIVES: To determine whether patients with glaucoma and epiretinal membrane (ERM) use a greater proportion of prostaglandin analogues (PA) than a control group of patients with glaucoma without ERM. METHOD: A retrospective study of cases and controls was conducted in order to determine whether patients with glaucoma and ERM used a greater proportion of PA than a control group of patients with glaucoma without ERM. The diagnosis of de ERM was made by clinical examination and optical coherence tomography. RESULTS: The mean age of the cases was 77 years (SD: 8.68; 95% CI: 74.3-79.4), compared to the controls with 63 years (SD: 16.6; 95% CI: 70.1-78.5). The cases included 50% (n = 26) men and 50% women (n=26), whereas in the controls 25.4% (n = 16) of the cases were men and 74.6% (n = 47) women. PA treatment was used in 59.6% (n = 31) and 60.3% (n = 38) of the cases and controls, respectively. There was no statistically significant difference in PA use between the 2 groups (P = .939). CONCLUSIONS: In this study, an association between the use of AP and the development of ERM could not be demonstrated

MRI Correlation of Radial Head Fractures and Forearm Injuries.

Background: Radial head fractures can be associated with soft tissue injuries of the forearm and wrist. The Essex-Lopresti injury can lead to significant morbidity, especially if the diagnosis is not made acutely. Better identification of such injuries is needed to allow optimal surgical treatment and prevent long-term sequelae. We used magnetic resonance imaging (MRI) to correlate the degree of soft tissue injuries with radial head fractures. Methods: Sixteen pairs of forearms with an associated radial head fracture in 15 patients prospectively underwent an MRI within 2 weeks of their injury. MRI findings were correlated with fracture type, associated soft tissue injury, and presence of symptomatic wrist pain. Results: According to the modified Mason classification, there were 8 type I, 5 type II, and 3 type III radial head fractures. Wrist pain was reported in 8 of 16 extremities, and 2 had associated wrist pathology, including an acute scaphoid fracture in 1 patient and a preexisting stage II scapholunate advanced collapse (SLAC) wrist in another patient. The MRI findings included an elbow effusion in all 16 patients, edema in the proximal third of the radius in 15 extremities, which extended to the middle third in 3 extremities, edema of the interosseous membrane (IOM) in 5 extremities, and edema of the soft tissues including the supinator and/or pronator quadratus in 13 extremities. Conclusions: Eighty percent of patients with edema of the IOM had associated wrist pain. Soft tissue injuries of the forearm did not correlate with the severity of the radial head fracture.

Bands, Chords, Tendons, and Membranes in the Heart: An Imaging Overview.

Crests, bands, chords, and membranes can be seen within the different cardiac chambers, with variable clinical significance. They can be incidental or can have clinical implications by causing hemodynamic disturbance. It is crucial to know the morphology and orientation of normal structures, aberrant or accessory muscles, and abnormal membranes to diagnose the hemodynamic disturbance associated with them. Newer generation computed tomographic scanners and faster magnetic resonance imaging sequences offer high spatial and temporal resolution allowing for acquisition of high resolution images of the cardiac chambers improving identification of small internal structures, such as papillary muscles, muscular bands, chords, and membranes. They also help in identification of other associated complications, malformations, and provide a road map for treatment. In this article, we review cross-sectional cardiac imaging findings of normal anatomical variants and distinctive imaging features of pathologic bands, chords, or membranes, which may produce significant hemodynamic changes and clinical symptomatology.

Morphological evaluation of the distal interosseous membrane using ultrasound.

Evidence from a recent cadaveric study has revealed that the thickness of the distal interosseous membrane (DIOM) of the forearm shows substantial individual variations, and a thick fibrous tissue known as the distal oblique bundle (DOB) was found in 40% specimens in the study. Another cadaveric study revealed that greater stability of the distal radioulnar joint (DRUJ) was obtained in a group with DOB following ulnar shortening than in a group without DOB. Thus, the presence of DOB influences the condition of DIOM and the ability of DIOM to provide stability to the compromised DRUJ. In the present study, we carried out a preoperative morphological evaluation of DIOM using ultrasound (US) and compared the US findings with intraoperative findings in order to investigate the efficacy and the meanings of this US evaluation. A total of 14 patients with various diseases or injuries of the distal forearm requiring corrective surgery were enrolled. The mean values of DIOM thickness as measured by US evaluation correlated well with those measured intraoperatively. The sensitivity of US evaluation in confirming presence of DOB was 80% when the presence of DOB bundle was judged by DIOM thickness. In addition, 4 of 5 patients with chronic DRUJ instability showed no DOB. This study suggested that US can be a useful tool in evaluating DIOM and for detecting the presence of DOB and may provide helpful information regarding DRUJ instability.

A rare case of nonobstructive membrane of the left atrial appendage.

The left atrial appendage (LAA) is a blind-ending, complex structure distinct from the body of the left atrium and is sometimes regarded as a minor extension of the atrium. However, it should routinely be evaluated as part of a transesophageal echocardiographic examination. In this study we describe the presence of a nonobstructive membrane traversing the cavity of the LAA, found incidentally on transesophageal echocardiography.

Non-obstructive membranes of the left atrial appendage.

The left atrial appendage (LAA) is a blind-ending, complex structure distinct from the body of the left atrium and is sometimes regarded as a minor extension of the atrium. However, it should routinely be analysed as part of a transoesophageal echocardiographic examination. In this study we describe the presence of a non-obstructive membrane traversing the cavity of the LAA, found incidentally on transoesophageal echocardiography.

Pathways of macrophage apoptosis within the interface membrane in aseptic loosening of prostheses.

Aseptic loosening is a major cause of failure of total hip arthroplasty (THA). Macrophage apoptosis in interface membrane has been proved to play an important role in the pathogenesis of aseptic loosening. The purpose of current study was to identify the apoptotic mechanism of macrophages in the interface membrane of aseptic loosening. We collected periprosthetic interface membrane from 23 patients undergoing the revision operations for aseptic loosening of hip joint prostheses. To serve as the control group, samples of capsule were collected from 18 patients undergoing the primary hip arthroplasties for osteoarthritis (OA). The ultrastructure of interface membrane was examined by transmission electron microscopy (TEM), and in situ apoptotic macrophage identification was performed by TUNEL staining. Furthermore, using immunohistochemical methods we investigated the expression of some apoptosis-related markers such as inducible nitric oxide synthase (iNOS), peroxynitrite (ONOO(-)), cleaved caspase-3/4/8/9, cytochrome c, glucose regulated protein 78 (GRP78), and growth arrest and DNA damage-inducible gene 153 (GADD153) in macrophages. These markers were regarded as apoptotic inducers or specific indicators of different apoptotic pathways such as death receptor pathway, mitochondrial pathway and endoplasmic reticulum (ER) stress pathway. TEM showed that a great deal of wear debris was phagocytosed by macrophages, which displayed morphological changes characteristic of apoptosis. The results of TUNEL staining demonstrated that there were more apoptotic macrophages in interface membrane. The expression levels of iNOS, ONOO(-), cleaved caspase-3/4/8/9, cytochrome c, GRP78 and GADD153 in macrophages in interface membrane were significantly higher than those in the control samples (p < 0.05). Our results suggest that death receptor pathway, mitochondria/cytochrosome c caspase-dependent pathway and ER stress pathway are involved in the process of macrophage apoptosis. A therapeutic target to modulate the apoptotic pathways in macrophages may be a strategy to prevent and treat aseptic loosening.

Two binding sites for [3H]PBR28 in human brain: implications for TSPO PET imaging of neuroinflammation.

[(11)C]PBR28, a radioligand targeting the translocator protein (TSPO), does not produce a specific binding signal in approximately 14% of healthy volunteers. This phenomenon has not been reported for [(11)C]PK11195, another TSPO radioligand. We measured the specific binding signals with [(3)H]PK11195 and [(3)H]PBR28 in brain tissue from 22 donors. Overall, 23% of the samples did not generate a visually detectable specific autoradiographic signal with [(3)H]PBR28, although all samples showed [(3)H]PK11195 binding. There was a marked reduction in the affinity of [(3)H]PBR28 for TSPO in samples with no visible [(3)H]PBR28 autoradiographic signal (K(i)=188+/-15.6 nmol/L), relative to those showing normal signal (K(i)=3.4+/-0.5 nmol/L, P<0.001). Of this latter group, [(3)H]PBR28 bound with a two-site fit in 40% of cases, with affinities (K(i)) of 4.0+/-2.4 nmol/L (high-affinity site) and 313+/-77 nmol/L (low-affinity site). There was no difference in K(d) or B(max) for [(3)H]PK11195 in samples showing no [(3)H]PBR28 autoradiographic signal relative to those showing normal [(3)H]PBR28 autoradiographic signal. [(3)H]PK11195 bound with a single site for all samples. The existence of three different binding patterns with PBR28 (high-affinity binding (46%), low-affinity binding (23%), and two-site binding (31%)) suggests that a reduction in [(11)C]PBR28 binding may not be interpreted simply as a reduction in TSPO density. The functional significance of differences in binding characteristics warrants further investigation.

Membranous Budd-Chiari syndrome in Caucasians.

OBJECTIVE: Budd-Chiari syndrome (BCS) is characterized by an obstruction of hepatic venous outflow. Membranous obstruction of the inferior vena cava (IVC) is a curable cause of primary BCS but is very rare in Western Europe. To date, there is only very limited information on membranous BCS in the Western world. We here report the diagnosis and management of five Caucasian patients with membranous BCS. MATERIAL AND METHODS: Out of 23 patients with BCS diagnosed between 2004 and 2007 we identified five with a membranous web of the IVC. Diagnostic evaluation of BCS included laboratory tests, ultrasound Doppler imaging, CT and MRI. RESULTS: The clinical presentation of membranous BCS was heterogeneous. The time frame from first clinical symptoms to diagnosis ranged from 3 weeks to 60 years. Liver cirrhosis was misdiagnosed in 4/5 patients. CT did not establish the correct diagnosis of membranous BCS in any of our patients. In contrast, abdominal Doppler ultrasonography showed collaterals and a web in the IVC which was confirmed by Doppler-MRI and hepatovenography. Four patients underwent interventional treatment with balloon dilatation of short-segment venous stenoses or complete occlusions. Therapy was successful: in all cases it resulted in a normalized extrahepatic blood flow and reduction of spleen size. CONCLUSIONS: Membranous BCS may be underdiagnosed in Caucasians. Doppler ultrasound should be used as the initial diagnostic procedure for membranous BCS. Although CT is considered the "gold standard" in addition to angiography, it could not detect membranous obliteration in our cases. Patients can be effectively treated by interventional endovascular therapy.

Interosseous membrane of the forearm: length change of ligaments during forearm rotation.

PURPOSE: An earlier anatomic study described five ligamentous components in the interosseous membrane of the forearm (central band, accessory band, distal oblique bundle, proximal oblique cord, and dorsal oblique accessory cord) and provided their precise location of attachment. In the present study, we investigated in vivo length changes of these five ligaments during forearm rotation to understand the function of each ligament. METHODS: We acquired computed tomographies of nine forearms from seven healthy volunteers for 3 rotation positions: maximum pronation, neutral position, and maximum supination. We created 3-dimensional models of the radius, ulna, and the 5 ligaments by combining osseous images and anatomic data of ligament attachment. We calculated 3-dimensional ligament lengths between attachments during forearm rotation using a markerless bone registration technique. We also examined relationships between the axis of forearm rotation and each ligament. RESULTS: The distal 3 ligaments (central band, accessory band, and distal oblique bundle) had little change in length during forearm rotation, with their ulnar attachments located almost on the axis of forearm rotation. The 2 proximal ligaments (proximal oblique cord and dorsal oblique accessory cord) changed substantially in length, with their attachments out of the course of the axis. CONCLUSIONS: The distal 3 ligaments of the interosseous membrane are essentially isometric stabilizers of the forearm. The distal oblique bundle in the distal membranous portion may stabilize the distal radioulnar joint in 40% of human subjects who have this ligament.