Small Calcifications Research Articles

Image quality and dose reduction opportunity of deep learning image reconstruction algorithm for CT: a phantom study.

To assess the impact on image quality and dose reduction of a new deep learning image reconstruction (DLIR) algorithm compared with a hybrid iterative reconstruction (IR) algorithm. Data acquisitions were performed at seven dose levels (CTDIvol :15/10/7.5/5/2.5/1/0.5mGy) using a standard phantom designed for image quality assessment. Raw data were reconstructed using the filtered back projection (FBP), two levels of IR (ASiR-V50% (AV50); ASiR-V100% (AV100)), and three levels of DLIR (TrueFidelity™ low, medium, high). Noise power spectrum (NPS) and task-based transfer function (TTF) were computed. Detectability index (d') was computed to model a large mass in the liver, a small calcification, and a small subtle lesion with low contrast. NPS peaks were higher with AV50 than with all DLIR levels and only higher with DLIR-H than with AV100. The average NPS spatial frequencies were higher with DLIR than with IR. For all DLIR levels, TTF50% obtained with DLIR was higher than that with IR. d' was higher with DLIR than with AV50 but lower with DLIR-L and DLIR-M than with AV100. d' values were higher with DLIR-H than with AV100 for the small low-contrast lesion (10 ± 4%) and in the same range for the other simulated lesions. New DLIR algorithm reduced noise and improved spatial resolution and detectability without changing the noise texture. Images obtained with DLIR seem to indicate a greater potential for dose optimization than those with hybrid IR. • This study assessed the impact on image quality and radiation dose of a new deep learning image reconstruction (DLIR) algorithm as compared with hybrid iterative reconstruction (IR) algorithm. • The new DLIR algorithm reduced noise and improved spatial resolution and detectability without perceived alteration of the texture, commonly reported with IR. • As compared with IR, DLIR seems to open further possibility of dose optimization.

Dose reduction for CT coronary calcium scoring with a calcium-aware image reconstruction technique: a phantom study

ObjectiveTo assess the dose reduction potential of a calcium-aware reconstruction technique, which aims at tube voltage-independent computed tomography (CT) numbers for calcium.Methods and materialsA cardiothoracic phantom, mimicking three different patient sizes, was scanned with two calcium inserts (named D100 and CCI), containing calcifications varying in size and density. Tube voltage was varied both manually (range 70–150 and Sn100 kVp) and automatically. Tube current was automatically adapted to maintain reference image quality defined at 120 kVp. Data was reconstructed with the standard reconstruction technique (kernel Qr36) and the calcium-aware reconstruction technique (kernel Sa36). We assessed the radiation dose reduction potential (volumetric CT dose index values (CTDIvol)), noise (standard deviation (SD)), mean CT number (HU) of each calcification, and Agatston scores for varying kVp. Results were compared with the reference acquired at 120 kVp and reconstructed with Qr36.ResultsAutomatic selection of the optimal tube voltage resulted in a CTDIvol reduction of 22%, 15%, and 12% compared with the reference for the small, medium, and large phantom, respectively. CT numbers differed up to 64% for the standard reconstruction and 11% for the calcium-aware reconstruction. Similarly, Agatston scores deviated up to 40% and 8% for the standard and calcium-aware reconstruction technique, respectively.ConclusionCT numbers remained consistent with comparable calcium scores when the calcium-aware image reconstruction technique was applied with varying tube voltage. Less consistency was observed in small calcifications with low density. Automatic reduction of tube voltage resulted in a dose reduction of up to 22%.Key Points• The calcium-aware image reconstruction technique allows for consistent CT numbers when varying the tube voltage.• Automatic reduction of tube voltage results in a reduced radiation exposure of up to 22%.• This study stresses the known limitations of the current Agatston score technique.

Correlation between risk factors of cerebrovascular disease and calcified plaque characteristics in patients with atherosclerotic severe carotid stenosis

ABSTRACTObjectives: The aim of this study was to evaluate the relationship between the risk factors of cerebral vascular diseases (CVD) and the characteristics of calcified plaques in patients with severe carotid arteriosclerosis stenosis (SCAS).Methods: A total of 402 patients with SCAS who were treated in our hospital between January to December 2016 were included in this study. The patients were divided into calcified plaque group and non-calcified plaque group according to the ultrasonography and computerized tomography angiography (CTA) or digital subtraction angiography (DSA) imaging of SCAS-responsible plaque and the characteristics of calcified plaques evaluated by high-frequency ultrasound.Results: The patients with long-term diabetes mellitus or higher levels of fasting blood glucose were more likely to develop calcified plaques (P = 0.00 and P = 0.021, respectively). In addition, the patients with calcified plaques were mostly smokers (P = 0.016). Their smoking duration and accumulative smoking exposure were higher than those without calcified plaque (P = 0.006 and P = 0.007, respectively). The basal location of calcification (P = 0.004) and the type of patchy calcification (P = 0.00) were both easier to appear in smokers, while non-smokers were more likely to have small granular calcification (P = 0.002). Furthermore, the carotid plaque calcification with mixed-location were more frequently seen in patients with hypertension (P = 0.016). The risk factors independently associated with plaque calcification were significantly associated with smoking status, smoking age, and accumulative smoking exposure, as well as age and diabetes mellitus (all P < 0.05).Conclusion: Smoking, diabetes mellitus and age were independent risk factors for carotid plaque calcification. Smoking and hypertension were associated with specific locations and types of plaque calcification.

An entity that poses continuous challenge despite treatment attempt: lymphangioleiomyomatosis.

In May of 2016, a 37-years-old Hispanic female, with no significant past medical history was brought to our hospital with right-sided chest pain. Chest X ray revealed large right pneumothorax (A) and she underwent chest tube placement. Computed tomography (CT) chest without contrast showed innumerable cysts in the upper and lower lobes of bilateral lungs (B) and right thoracostomy tube with very small residual pneumothorax (C). CT abdomen showed hyperdense mass in left and possibly right kidney (D). CT head without contrast showed small calcifications in the lateral ventricles suggestive of tubers (E). A diagnosis of lymphangioleiomyomatosis (LAM) was suspected. Serum vascular endothelial growth factor D was < 800 pg/ml. She underwent open lung biopsy and diagnosis of LAM was established after histopathologic evaluation. Patient was sent to LAM clinic at a higher center and was started on sirolimus with an aim to stabilize her lung function, improve quality of life and functional performance. Since, sirolimus is used for suppressive rather than curative intent, patient has had 4 more episodes of spontaneous pneumothoaraces in last four years. Her last admission was in May of 2020 due to left sided secondary spontaneous pneumothorax (F), which completely resolved in 2 weeks without chest tube insertion (G).

Measurement of coronary artery calcium volume using ultra-high-resolution computed tomography: A preliminary phantom and cadaver study

ObjectivesIn this phantom- and cadaver study we investigated the differences of coronary artery calcium (CAC) volume on ultra-high-resolution computed tomography (U-HRCT) scans and conventional CT. MethodsWe scanned a coronary calcium phantom and the coronary arteries of five cadavers using U-HRCT in normal- and super-high resolution (NR, SHR) mode. The NR mode was similar to conventional CT; 896 detector channels, a matrix size of 512, and a slice thickness of 0.5 mm were applied. In SHR mode, we used 1792 detector channels, a matrix size of 1024, and a slice thickness of 0.25 mm. The CAC volume on NR- and SHR images were recorded. Differences in the physical- and the calculated CAC volume were defined as the error value and compared between NR- and SHR images of the phantom. Differences between the CAC volume on NR- and SHR scans of the cadavers were also recorded. ResultsThe mean error value was lower on SHR- than NR images of the phantom (14.0 %, SD 11.1 vs 20.1 %, SD 15.2, p = 0.01). The mean CAC volume was significantly higher on SHR- than NR images of the cadavers (153.4 mm3, SD 161.0 vs 144.7 mm3, SD 164.8, p < 0.01). ConclusionsAs small calcifications were more clearly visualized on U-HRCT images in SHR mode than on conventional (NR) CT scans, SHR imaging may facilitate the accurate quantification of the CAC.

Deep Efficient End-to-end Reconstruction (DEER) Network for Few-view Breast CT Image Reconstruction.

Breast CT provides image volumes with isotropic resolution in high contrast, enabling detection of small calcification (down to a few hundred microns in size) and subtle density differences. Since breast is sensitive to x-ray radiation, dose reduction of breast CT is an important topic, and for this purpose, few-view scanning is a main approach. In this article, we propose a Deep Efficient End-to-end Reconstruction (DEER) network for few-view breast CT image reconstruction. The major merits of our network include high dose efficiency, excellent image quality, and low model complexity. By the design, the proposed network can learn the reconstruction process with as few as parameters, where N is the side length of an image to be reconstructed, which represents orders of magnitude improvements relative to the state-of-the-art deep-learning-based reconstruction methods that map raw data to tomographic images directly. Also, validated on a cone-beam breast CT dataset prepared by Koning Corporation on a commercial scanner, our method demonstrates a competitive performance over the state-of-the-art reconstruction networks in terms of image quality. The source code of this paper is available at: https://github.com/HuidongXie/DEER.

Pathology of radiation induced heart disease.

The aim of this paper is dual - to review the relevant literature on pathology of radiation induced heart disease (RIHD), and to present an illustrative case of our own. Therapeutic ionizing radiation, such as that used in the treatment of Hodgkin´s lymphoma and cancers of left breast, lungs, esophagus, and thymus, can cause cardiac damage that may take several years to manifest. The spectrum of RIHD is broad and includes [1] pericarditis and pericardial effusion; [2] endocardial fibrosis and valvular dysfunction; [3] nonischemic myocardial fibrosis; [4] obstructive coronary artery disease with resultant myocardial ischemia; [5] damage to the great vessels; and [6] conduction system dysfunction. Pericardial disease, however, is the most common manifestation of mediastinal irradiation. A case is described of a typical RIHD in a 52-year-old female who died from heart failure with a history of mediastinal neuroblastoma operated and irradiated at the age of 9 years. Her autopsy heart lesions comprised chronic and acute pericarditis with constrictive features, myocardial fibrosis with features of restrictive cardiomyopathy and fibrosis with calcification of the left heart valves. As a unique lesion, there were small calcifications in the mural endocardium and in the large arterial intima. This finding seems to be diagnostic for RIHD.

ERUPTION MESENCHYMAL CALCIFIED HAMARTOMA: A CASE REPORT

Eruption mesenchymal calcified hamartoma (formerly known as eruption sequestrum) is an uncommon proliferation of odontogenic calcified structures, usually observed in the opercula of lower first molars of delayed eruption. A 6-year-old Brazilian girl was seen for routine dental examination. A fragment of hard whitish tissue was observed in the gingiva overlying the erupting lower first permanent molar, which showed radiographic appearance of a 0.5-cm faint round radiopacity above and separated from the occlusal surface of the related molar. The patient was submitted to an excisional biopsy, and gross examination showed a hardened whitish fragment surrounded by gingival mucosa. Microscopically, limited proliferation of cords of odontogenic epithelium was observed in association with small concentric basophilic calcifications and few large, round osteodentin and pulp-like structures. There were numerous inflammatory cells and small blood vessels in the surrounding connective tissue. The final diagnosis was eruption mesenchymal calcified hamartoma. Eruption mesenchymal calcified hamartoma (formerly known as eruption sequestrum) is an uncommon proliferation of odontogenic calcified structures, usually observed in the opercula of lower first molars of delayed eruption. A 6-year-old Brazilian girl was seen for routine dental examination. A fragment of hard whitish tissue was observed in the gingiva overlying the erupting lower first permanent molar, which showed radiographic appearance of a 0.5-cm faint round radiopacity above and separated from the occlusal surface of the related molar. The patient was submitted to an excisional biopsy, and gross examination showed a hardened whitish fragment surrounded by gingival mucosa. Microscopically, limited proliferation of cords of odontogenic epithelium was observed in association with small concentric basophilic calcifications and few large, round osteodentin and pulp-like structures. There were numerous inflammatory cells and small blood vessels in the surrounding connective tissue. The final diagnosis was eruption mesenchymal calcified hamartoma.

Prediction of Breast Cancer by Segmenting the Image from Mammography using Neural Network Classifier

An automated identification system to enable early identification of breast cancer which is one of the most familiartypes of cancer amidst females which is identified using a diagnostic technique called mammography. This identification ideologybanks on multiple instance learning (MIL) paradigms which demonstrate an aid in therapeutical assistance. Within the projected framework, breasts area unit is first divided adaptively into regions. The GLCM options are extracted from wavelet sub bands. A classification of diagnostic examination procedure as normal or abnormal is revealed from lesions which are masses or small calcifications and the textural options. To arrive at the final results the abovefactors are interpreted from all parts and analysed.In the event of an anomaly found in thereport, the parts that are detected by the machine driven identification will be displayed. Dual evaluation methodology is undertaken to outline this deviation. A neural network has to be trained before utilization; it is done by segmenting the lesions and feeding it to NN. The NN assigns an anomaly index to them and then the combination of local and global anomaly index takes place.

Incidental finding of diffuse cavernous rectal haemangiomatosis during bowel cancer screening

BackgroundThis case seeks to highlight to endoscopists a rare benign disorder that may be encountered during endoscopy. Clinicians may be tempted to biopsy, which could lead to a catastrophic gastrointestinal haemorrhage.Case presentationA 66-year-old asymptomatic Caucasian male was referred for colonoscopy with a positive faecal occult blood test as part of the UK national bowel cancer screening programme. Relevant past medical history included atrial fibrillation for which he took Dabigatran. He had a normal haemoglobin, mean cell volume, platelet and clotting function.During colonoscopy, an unusual vascular pattern encompassing the entire rectum extending to the rectosigmoid junction was noted at intubation. The lesion demonstrated confluent circumferential purple discolouration indicating venous blood supply, with heaping up of the mucosa involving the entire rectum and rectosigmoid junction. There was no corresponding history of venothromboembolic disease or liver disease. The patient proceeded to have computed tomography (CT) which revealed a considerably thickened rectosigmoid wall with multiple small rounded punctate calcifications within it, and no other visceral involvement. Subsequent magnetic resonance (MR) scan of the pelvis demonstrated extensive diffuse thickening of the rectum and lower sigmoid with intermediate to high T2 signal, and an internal architecture of multiple ‘grapelike’ lobulations.ConclusionThe findings were consistent with diffuse cavernous haemangiomatosis of the rectum (DCHR), an extremely rare benign submucosal vascular intestinal tumour originating from the dentate line. Misdiagnosis of DCHR is common and the macroscopic appearance of DCHR can mimic varices, haemorrhoids, polyps or proctitis. MR imaging is the gold standard for diagnosis. Common presentation is with haematochezia due to mucosal wall erosion. The treatment of choice for symptomatic DCHR is pull-through transection and colo-anal anastomosis. This case seeks to highlight a rare disorder that can be encountered incidentally during lower GI endoscopy. Injudicious biopsy is potentially catastrophic. In a patient who endoscopically has evidence of a DCHR, we advocate MR pelvis assessment to clarify the nature of the lesion to guide future management if required. The patient discussed remains well, asymptomatic, with no evidence of iron deficiency anaemia.

Scrutiny of Breast Cancer Detection Techniques of Deeplearning and Machine Learning

Breast cancer is one of the most widely recognized tumors globally among ladies with the data available that one of every eight ladies is influenced by this illness during their lifetime. Mammography is the best imaging methodology for early location of the disease in beginning times. On account of poor complexity and low perceivability in the mammographic pictures, early discovery of the cancer malignant growth is a huge challenge to effective cure of the disease. Distinctive CAD (computer aided detection) supported algorithms have been developed to enable radiologists to give an exact determination. This paper highlights the study of the most widely recognized methodologies of image segmentation created for recognition of calcifications and masses. The principle focal point of this survey is on picture theof strategies and the factors utilized for early bosom disease identification. Surface investigation is the vital advance in any picture division strategies of image segmentation which depend on a nearby spatial variety of color or shading. Subsequently, different techniques for texture investigation for small scale calcification and mass identification in mammography are talked about in the mechanism of mammography. The point of this paper is to audit existing ways to deal with the segmentation of masses and automated detection in mammographic pictures, underlining the key-focuses and primary contrasts among the utilized systems. The key goal is to bring up the preferences and drawbacks of the different methodologies. Conversely with different surveys which just portray and think about various methodologies subjectively, this audit likewise gives a quantifiable examination.In proposed research use deep learning base network for classification of mammography images . In previous approaches use machine learning base learning. The Main drawback of machine learning is selection of features manualy or by functions but in deep learning automatic feature detect and its vary according to image. The demonstration of seven mass recognition techniques is thought about utilizing two distinctive databases of mammography: an open digitized database and a full-field (local) advanced digitized database. The outcomes are given as far as Free reaction Receiver Operating Characteristic (FROC) and Receiver Operating Characteristic (ROC) examination.

2452 Intrahepatic Portosystemic Venous Shunt: A Clinically Significant Rare Anomaly

INTRODUCTION: Intrahepatic Portosystemic Venous Shunts (IPSVS) are rare vascular malformations between the hepatic and portal veins. Most of the porto-venous shunts are asymptomatic and found incidentally on radiology imaging. These can be either congenital or acquired. Acquired shunts are typically less than 2 mm in size. Occasionally, complications such as encephalopathy, heart failure, pulmonary hypertension and elevated ammonia levels can occur. We report a case of incidental IPSVS in a patient who presented with complaints of fatigue and failure to thrive. CASE DESCRIPTION/METHODS: 82-year-old African American male with hypertension, diabetes mellitus and prostate cancer (treated) presented with complaints of fatigue and loss of appetite for one-month. Laboratory work up showed a hemoglobin of 11.6 g/dl, normal platelet count, and elevated aspartate aminotransferase of 45 U/L and decreased albumin of 2.0 g/dl. Serum ammonia level was normal. He was immune to hepatitis A, non immune to hepatitis B and hepatitis C antibody was negative. A computed tomography scan of the abdomen showed a contrast enhanced tubular shaped vascular connection between middle hepatic vein and the anterior branch of the right portal vein. The size of the shunt was approximately 10 mm (Figure 1). Liver appeared normal except for small calcifications within the parenchyma. Ultrasound Doppler of hepatic and portal veins were performed, and the porto-hepatic shunt was visualized (Figure 2). Patient had a complicated hospital course secondary to sepsis; however, he did not develop hyperammonemia or hepatic encephalopathy during the hospital stay. DISCUSSION: IPSVS in our patient was likely a congenital anomaly given the presentation, size and lack of related symptoms. IPSVS is divided into 4 types; Type 1- Shunt between portal vein and IVC; Type 2- connections between peripheral branches of portal and hepatic veins in one hepatic segment; Type 3- Aneurysmal connection between portal and hepatic vein; Type 4- multiple communications of portal and hepatic veins in both major lobes of the liver. Doppler sonogram with pulse doppler is highly sensitive and specific to evaluate for IPSVS. In symptomatic IPSVS, shunt closure has shown improvement in symptoms and correction of hyperammonemia. Clinicians should consider this rare vascular malformation in patients presenting with hepatic encephalopathy or hyperammonemia in the absence of cirrhosis where shunt closure can be curative.

A case study of galen aneurysmal malformation in Bamako

Galen aneurysmal malformation is a rare complex congenital vascular malformation of the brain, (less than 1% of intracranial arteriovenous malformations) characterized by pseudoaneurismal dilation of Galen's ampulla associated with one or several arteriovenous fistulas. In most cases, diagnosis is made in the neonatal or postnatal period, exceptionally in adulthood. We report the case of an 18-year male patient hospitalized for psychomotor retardation. Brain computed tomography (CT) scan using spontaneous contrast (A,B,C) showed voluminous isodense mass in the pineal region behind the third ventricle with peripheral calcifications, compatible with large vein of galen aneurysm. Its anteroposterior diameter was 8.5cm, its transverse diameter was 3cm in the axial plane (C) and its height was 3cm in the sagittal plane (G). Imaging objectified homogeneous contrast enhancement (D,E,F,G,H,I). The mass was associated with dilation of the superior sagittal sinus measured at 2.7cm (A,D), of transverse sinuses measured at 1.5cm to the right and at 1,1cm to the left (B,E). Multiple venous perianeurysmal derivations (I), hydrocephaly and small parenchymal cortical-subcortical calcifications were detected. Embolization can't be performed in Bamako, so the patient is waiting for transfer.

Photon-counting cine-cardiac CT in the mouse.

The maturation of photon-counting detector (PCD) technology promises to enhance routine CT imaging applications with high-fidelity spectral information. In this paper, we demonstrate the power of this synergy and our complementary reconstruction techniques, performing 4D, cardiac PCD-CT data acquisition and reconstruction in a mouse model of atherosclerosis, including calcified plaque. Specifically, in vivo cardiac micro-CT scans were performed in four ApoE knockout mice, following their development of calcified plaques. The scans were performed with a prototype PCD (DECTRIS, Ltd.) with 4 energy thresholds. Projections were sampled every 10 ms with a 10 ms exposure, allowing the reconstruction of 10 cardiac phases at each of 4 energies (40 total 3D volumes per mouse scan). Reconstruction was performed iteratively using the split Bregman method with constraints on spectral rank and spatio-temporal gradient sparsity. The reconstructed images represent the first in vivo, 4D PCD-CT data in a mouse model of atherosclerosis. Robust regularization during iterative reconstruction yields high-fidelity results: an 8-fold reduction in noise standard deviation for the highest energy threshold (relative to unregularized algebraic reconstruction), while absolute spectral bias measurements remain below 13 Hounsfield units across all energy thresholds and scans. Qualitatively, image domain material decomposition results show clear separation of iodinated contrast and soft tissue from calcified plaque in the in vivo data. Quantitatively, spatial, spectral, and temporal fidelity are verified through a water phantom scan and a realistic MOBY phantom simulation experiment: spatial resolution is robustly preserved by iterative reconstruction (10% MTF: 2.8–3.0 lp/mm), left-ventricle, cardiac functional metrics can be measured from iodine map segmentations with ~1% error, and small calcifications (615 μm) can be detected during slow moving phases of the cardiac cycle. Given these preliminary results, we believe that PCD technology will enhance dynamic CT imaging applications with high-fidelity spectral and material information.

CT iterative reconstruction algorithms: a task-based image quality assessment.

To assess the dose performance in terms of image quality of filtered back projection (FBP) and two generations of iterative reconstruction (IR) algorithms developed by the most common CT vendors. We used four CT systems equipped with a hybrid/statistical IR (H/SIR) and a full/partial/advanced model-based IR (MBIR) algorithms. Acquisitions were performed on an ACR phantom at five dose levels. Raw data were reconstructed using a standard soft tissue kernel for FBP and one iterative level of the two IR algorithm generations. The noise power spectrum (NPS) and the task-based transfer function (TTF) were computed. A detectability index (d') was computed to model the detection task of a large mass in the liver (large feature; 120HU and 25-mm diameter) and a small calcification (small feature; 500HU and 1.5-mm diameter). With H/SIR, the highest values of d' for both features were found for Siemens, then for Canon and the lowest values for Philips and GE. For the large feature, potential dose reductions with MBIR compared with H/SIR were - 35% for GE, - 62% for Philips, and - 13% for Siemens; for the small feature, corresponding reductions were - 45%, - 78%, and - 14%, respectively. With the Canon system, a potential dose reduction of - 32% was observed only for the small feature with MBIR compared with the H/SIR algorithm. For the large feature, the dose increased by 100%. This multivendor comparison of several versions of IR algorithms allowed to compare the different evolution within each vendor. The use of d' is highly adapted and robust for an optimization process. • The performance of four CT systems was evaluated by using imQuest software to assess noise characteristic, spatial resolution, and lesion detection. • Two task functions were defined to model the detection task of a large mass in the liver and a small calcification. • The advantage of task-based image quality assessment for radiologists is that it does not include only complicated metrics, but also clinically meaningful image quality.

Alternative Percutaneous Access for Large Bore Devices.

Common femoral artery access is the default strategy for large-bore interventional procedures, including temporary mechanical circulatory support implantation and structural heart therapies, based on superior outcomes and operator ease. However, the size and caliber of the iliofemoral arterial system are influenced by patient size, sex, and comorbidities. Small vessel caliber, significant calcification or atheroma, and severe tortuosity may place patients at prohibitively high risk or render common femoral access impossible. Given the rapid growth of large-bore transcatheter procedures, bleeding avoidance strategies are essential, and thus, novel mechanisms for large-bore access have evolved. This article will discuss the advantages, limitations, and methods of the 2 most common percutaneous large-bore alternative access strategies: transaxillary and transcaval access.

Macroscopic evaluation of the placenta of the alpaca (Vicugna pacos).

Macroscopic evaluation of the placenta is an essential post-partum examination in the alpaca and can be of special interest in case of abortion, premature birth or stillbirth. Since there are not many reference values regarding macroscopic properties of normal alpaca placentas, a small descriptive study was conducted. Only placentae from normally foaling alpaca mares, giving birth to healthy crias, after a full-term and uneventful gestation (±350days; range 335-360days) were taken into account (N=11). Crias weighed (±SD) 7.7±2.25kg (range 5.5-10kg), while the mean weight of the full-term placentas was 0.8±0.19kg, that is 10% of the bodyweight of the crias. The weight of the allantoamnion and chorion was 0.2±0.07kg and 0.5±0.13kg, respectively. The umbilical cord length was 8.8±2.84cm, and the length of the pregnant and non-pregnant uterine horns was 69.4±12.77cm and 54.5±6.81cm, respectively. The length of the corpus was 14.6±4.68cm, and the distance from the umbilicus to the corpus was 18.5±6.13cm. The tissue volume of the allantoamnion was 0.14±0.079L, and the chorionic volume was 0.37±0.078L. The surface area of the allantoamnion and the chorion was 87.6±15.56dm2 and 72.3±9.28dm2 , respectively. All placentas had small calcifications either around the umbilical cord alone or around the umbilicus and blood vessels of the pregnant uterine horn. These measurements could be used to macroscopically evaluate alpaca placentas, although more research is needed to extend our knowledge of macroscopic evaluation of normal and abnormal placentas.

Biallelic MYORG mutation carriers exhibit primary brain calcification with a distinct phenotype.

Primary familial brain calcification (PFBC) is a rare neurogenetic disorder with diverse neuropsychiatric expression. Mutations in four genes cause autosomal dominant PFBC: SLC20A2, XPR1, PDGFB and PDGFRB. Recently, biallelic mutations in the MYORG gene have been reported to cause PFBC with an autosomal recessive pattern of inheritance. We screened MYORG in 29 unrelated probands negatively screened for the autosomal dominant PFBC genes and identified 11 families with a biallelic rare or novel predicted damaging variant. We studied the clinical and radiological features of 16 patients of these 11 families and compared them to that of 102 autosomal dominant PFBC patients carrying a mutation in one of the four known autosomal dominant PFBC genes. We found that MYORG patients exhibited a high clinical penetrance with a median age of onset of 52 years (range: 21-62) with motor impairment at the forefront. In particular, dysarthria was the presenting sign in 11/16 patients. In contrast to patients with autosomal dominant PFBC, 12/15 (80%) symptomatic patients eventually presented at least four of the following five symptoms: dysarthria, cerebellar syndrome, gait disorder of any origin, akinetic-hypertonic syndrome and pyramidal signs. In addition to the most severe clinical pattern, MYORG patients exhibited the most severe pattern of calcifications as compared to the patients from the four autosomal dominant PFBC gene categories. Strikingly, 12/15 presented with brainstem calcifications in addition to extensive calcifications in other brain areas (lenticular nuclei, thalamus, cerebellar hemispheres, vermis, ±cortex). Among them, eight patients exhibited pontine calcifications, which were observed in none of the autosomal dominant PFBC patients and hence appeared to be highly specific. Finally, all patients exhibited cerebellar atrophy with diverse degrees of severity on CT scans. We confirmed the existence of cerebellar atrophy by performing MRI voxel-based morphometry analyses of MYORG patients with autosomal dominant PFBC mutation carriers as a comparison group. Of note, in three families, the father carried small pallido-dentate calcifications while carrying the mutation at the heterozygous state, suggesting a putative phenotypic expression in some heterozygous carriers. In conclusion, we confirm that MYORG is a novel major PFBC causative gene and that the phenotype associated with such mutations may be recognized based on pedigree, clinical and radiological features.

ЭХОСТРУКТУРНАЯ И ПАТОМОРФОЛОГИЧЕСКАЯ ХАРАКТЕРИСТИКА ЛИКВОРНЫХ ПУТЕЙ ГОЛОВНОГО МОЗГА У ДОНОШЕННЫХ НОВОРОЖДЕННЫХ С ВРОЖДЕННОЙ ЦИТОМЕГАЛОВИРУСНОЙ ИНФЕКЦИЕЙ

In 36 full-term newborns who died at an early neonatal age under various conditions of intrauterine development, ultrasound examination and morphological study of the brain liquor space was conducted at the 1st-2nd days of life. The first group included 20 newborns aged 38-40 weeks, whose cause of death on the 4th -5th day of life was intranatal and postnatal hypoxia. The second group included 16 dead children of the same age with congenital cytomegalovirus infection. It was found out that immaturity (n=7, p&lt;0.05), pseudocysts of the vascular plexus of the lateral ventricles (n=9, p&lt;0.5), as well as intraventricular hemorrhages of I degree (n=8, p&lt;0.05) were more often diagnosed in the second group compared with the first one in neurosonographic study. Only in the second group there was a pronounced ventriculomegaly. A morphological study in the brain often detected a pronounced pericellular and perivascular edema, alterative changes of neurons, vasculitis (n=7), subependyma (n=3), choriocephalitis (n=3) and encephalitis (n=1) with small calcifications, ependymocyte desquamation and lymphocytic infiltration, with a pronounced hyperemia and hemorrhages. In all cases, specific cells of the "owl's eye" were not detected. The detected ultrasound and pathomorphological changes in the liquor space in intrauterine cytomegalovirus infection indicate the possibility of direct cytodestructive effect of the pathogen in the absence of markers of viral metamorphosis, as well as the indirect effect of antenatal hypoxia, endotoxemia and cytokineemia on the brain in newborns

Model and human observer reproducibility for detection of microcalcification clusters in digital breast tomosynthesis images of three-dimensionally structured test object.

We compare the reproducibility of the human observers and a channelized Hotelling observer (CHO), when reading digital breast tomosynthesis (DBT) images of a physical phantom containing a breast simulating structured background and calcification clusters at three dose levels. The phantom is scanned 217 times on a Siemens Inspiration DBT system. Volumes of interest, with and without the calcification targets, are extracted and the human observers' percentage of correct (PC) scores is evaluated using a four-alternative forced choice method. A two-layer CHO is developed using the human observer results. The first layer consists of a localizing CHO that identifies the most conspicuous calcifications using two Laguerre-Gauss channels. Then a CHO with eight Gabor channels estimates the PC score for the calcification cluster. Observer reproducibility is estimated by bootstrapping, and the standard deviation (SD) is used as a figure of merit. The CHO closely approximated the human observer results for all the three dose levels with a correlation of . For the larger calcification cluster sizes, both observers have similar reproducibility, whereas the CHO is more reproducible for the smaller calcifications, with a maximum of 5.5 SD against 13.1 SD for the human observers. The developed CHO is a good candidate for automated reading of the calcification clusters of the structured phantom, with better reproducibility than the human readers for small calcifications.