A case report of transmural rectosigmoid ischemia in an elderly patient.

INTRODUCTION AND IMPORTANCE: While acute colonic ischemia is frequently observed in the elderly, rectal ischemia is a rare occurrence. We presented a case of transmural rectosigmoid ischemia in a patient who had not undergone any significant interventions and had no underlying diseases. Conservative treatment methods were unsuccessful, and surgical resection was necessary to prevent the development of gangrene or sepsis. CASE PRESENTATION: Upon arrival at our health center, a 69-year-old man reported experiencing left lower quadrant pain and rectorrhagia. The CT scan revealed thickening in the sigmoid and rectum. Subsequent colonoscopy revealed circumferential ulcers, severe edema, erythema, discoloration, and ulcerative mucosa in both the rectum and sigmoid. Due to persistent severe rectorrhagia and worsening pathologic parameters, another colonoscopy was performed three days later. CLINICAL DISCUSSION: Initially, conservative treatments were administered, but as the tenderness worsened, surgical exploration of the abdomen was necessary. During the procedure, a large ischemia from the sigmoid to the rectal dentate line was observed, and the lesion was resected. A stapler was then inserted into the rectum, followed by the use of the Hartman pouch method to deviate the tract. Finally, colectomy, sigmoidectomy, and rectal resection were performed. CONCLUSION: Due to the worsening pathological condition of our patient, surgical resection was necessary. It is important to note that rectosigmoid ischemia, although rare, can develop without a known underlying cause. Therefore, it is crucial to consider and evaluate potential causes beyond the most common ones. Furthermore, any pain or rectorragia should be assessed immediately.

Medical image alignment based on landmark- and approximate contour-matching.

Purpose: Our goal is to propose a landmark- and contour-matching (LCM) registration method that uses both landmark information and approximate point correspondences to boost the similarity between image pairs with sparse landmark information. Approach: A model for registering two-dimensional (2D) medical images with landmark information and contour-approximating landmarks was proposed. The model was also extended to accommodate the registration of three-dimensional (3D) cardiac images. We validated the LCM method on 2D hand x-rays and 3D porcine cardiac magnetic resonance images. The following metrics were used to assess the quality of specific aspects of the registered images: Dice similarity coefficient for the overall image overlap, target registration error for pointwise correspondence, and interior angle for local curvature. Results: Target registrations were reduced from 27.12 to 0.01 mm post-LCM registration. Implementing the proposed algorithm also led to a 112% average improvement in image similarity in terms of Dice coefficients. In addition, interior angle measurements indicate that the proposed method preserved the local curvature at major reference landmarks and mitigated the appearance of deformities in the registered images. Conclusions: The proposed method addressed several issues associated with purely landmark-based techniques, such as iterative closest point registration and thin plate spline interpolation. Furthermore, it provided accurate registration results even in the presence of landmark localization errors.

Dyspnea and Cough: A Rare Report of the Kimura Disease.

BACKGROUND: Known as a rare disease, Kimura disease is a chronic, allergic and inflammatory process. It may overlap other allergic conditions, as well. CASE PRESENTATION: This study is going to present a 36-year-old woman, with cough, dyspnea and bone pain. Other differential diagnoses were excluded during the investigations. The definite diagnosis was made by excisional biopsy and pathological investigations. CONCLUSION: This was a rare medical condition with remarkable diagnostic challenge.

Novel atlas of fiber directions built from ex-vivo diffusion tensor images of porcine hearts.

Cardiac MR image-based predictive models integrating statistical atlases of heart anatomy and fiber orientations can aid in better diagnosis of cardiovascular disease, a major cause of death worldwide. Such atlases have been built from diffusion tensor (DT) images and can be used in anisotropic models for personalized computational electro-mechanical simulations when the fiber directions from DTI are not available. In this paper, we propose a framework for building the first statistical fiber atlas from high-resolution ex-vivo DT images of porcine hearts. A mean geometry that represents the average cardiac morphology of the dataset was first generated via groupwise registration. Then, the associated average cardiac fiber architecture was mapped out by computing the mean of the transformed DT fields of the subjects. To evaluate the stability of the atlas, we performed leave-one-out cross-validation. The resulting tensor statistics indicate that the fiber atlas could accurately describe the fiber architecture of a healthy pig heart.

Identifying lesions in paediatric epilepsy using morphometric and textural analysis of magnetic resonance images.

We seek to examine the use of an image processing pipeline on Magnetic Resonance Imaging (MRI) to identify features of Focal Cortical Dysplasia (FCD) in children who were suspected to have FCD on MRI (MRI-positive) and those with MRI-negative epilepsy. We aim to use a computer-aided diagnosis system to identify epileptogenic lesions with a combination of established morphometric features and textural analysis using Gray-Level Co-occurrence Matrices (GLCM) on MRI sequences. We implemented a modified version of the 2-Step Bayesian classifier method to a paediatric cohort with medically intractable epilepsy with MRI-positive and MRI-negative epilepsy, and evaluated the performance of the algorithm trained on textural features derived from T1-weighted (T1-w), T2-weighted (T2-w), and FLAIR (Fluid Attenuated Inversion Recovery) sequences. For MRI-positive cases, T1-w has the highest subjectwise sensitivity relative to T2-w and FLAIR (94% vs. 90% vs. 71% respectively), and also the highest lesional sensitivity (63% vs. 60% vs. 42% respectively), but the lowest lesional specificity (75% vs. 80% vs. 89% respectively). Combination of all three sequences improved the performance of the algorithm, with 97% subjectwise sensitivity. For MRI-negative cases, T1-w has the highest subjectwise sensitivity relative to T2-w and FLAIR (48% vs. 30% vs. 39% respectively), and also the highest lesional sensitivity (31% vs. 22% vs. 28% respectively). However, T2-w has the highest lesional specificity relative to T1-w and FLAIR (95% vs. 94% vs. 92% respectively) for MRI-negative cases. Combination of all three sequences improved the performance of the algorithm, with 70% subjectwise sensitivity. The 2-Step Naïve Bayes classifier correctly rejected 100% of the healthy subjects for all three sequences. Using combined morphometric and textural analysis in a 2-Step Bayesian classifier, applied to multiple MRI sequences, can assist with lesion detection in children with intractable epilepsy.

Does Adding Intravenous Phosphorus to Parenteral Nutrition Has Any Effects on Calcium and Phosphorus Metabolism and Bone Mineral Content in Preterm Neonates?

The use of parenteral nutritional supplementation of phosphorus may lead to exhibit higher plasma phosphate concentrations and less radiological features in premature neonates susceptible to osteopenia. The present study aimed to assess the beneficial effects of adding intravenous phosphorus to total parenteral nutrition (TPN) on calcium and phosphorus metabolism in preterm neonates by measuring bone mineral content. This open-labeled randomized clinical trial was conducted on premature neonates who were hospitalized at NICU. The neonates were randomly assigned to two groups received TPN with intravenous sodium glycerophosphate or Glycophos (1.5 mmol/kg/day) or TPN without sodium glycerophosphate. At the end of the four weeks of treatment, the presence of osteopenia was examined using DEXA Scan. After completing treatment protocols, the group received TPN with intravenous Glycophos had significantly lower serum alkaline phosphatase (360±60 versus 762±71, P<0.001), as well as higher serum calcium to creatinine ratio (1.6±0.3 versus 0.44±0.13, P<0.001) compared to the control group received TPN without Glycophos. Those who received TPN with intravenous Glycophos experienced more increase in bone mineral density than those in control group (0.13±0.01 versus 0.10±0.02, P<0.001). There was no significant difference in serum calcium and serum vitamin D between the case and control groups. Adding intravenous sodium glycerophosphate to TPN in premature neonates can compensate the lack of bone mineral content and help to prevent osteopenia.

Comparison of Bone Mineral Density in Common Variable Immunodeficiency and X-Linked Agammaglobulinaemia Patients.

BACKGROUND: Primary antibody deficiency (PAD) is the most common group of primary immunodeficiency disorders, resulting from different defects in the development and function of B cell lineage. Common variable immunodeficiency (CVID) and X-linked agammaglobulinemia (XLA) are two of the major types of PADs. Optimal growth and subsequently bone health could potentially compromise due to the interference of several factors in PAD with childhood onset. In the present study, our aim was to evaluate bone mineral density (BMD) of patients with CVID and XLA. METHODS: BMD of 37 CVID and 19 XLA patients was examined. Total BMD was determined by dual-energy X-ray absorptiometry and the calculated scores were compared internally and externally with age-sex matched and ethnic-specific reference. Related factors associated with bone density including immune-related complications, serum calcium, phosphate, total alkaline phosphatase, 25(OH) vitamin D and parathyroid hormone levels were recorded. RESULTS: The median age at the time of study was 20 years among all patients and was not statistically different between CVID and XLA groups and the mean of body mass index (BMI) was 19.4±4.6 kg/cm². Thirty-eight (67.9%) of total patients had normal BMD and 18 (32.1%) patients had a low BMD. BMI was positively correlated with BMD at lumbar spine and femoral neck. The number of low BMD patients in CVID (40.5%) group was more than the XLA (15.8%). CONCLUSION: Beside nutritional, gastrointestinal and infectious complications which are shared in both groups of patients, CVID patients are more prone to alteration of BMD due to association with lymphoproliferative and endocrine diseases. Therefore routine evaluation of bone density and treatment adjustment should be considered in all PAD patients particularly in CVID patients.

Long-term evaluation of a historical cohort of Iranian common variable immunodeficiency patients.

OBJECTIVES: Common variable immune deficiency (CVID) is the most frequent form of symptomatic primary immunodeficiency disease, characterized by hypogammaglobulinemia, recurrent infections and increased predisposition to autoimmunity and malignancies. The aim of this study was to reconsider important points of previously performed studies on Iranian CVID patients diagnosed and followed from 1984 to 2013. METHODS: Diagnosis was made using approved criteria including reductions of serum levels of immunoglobulins and exclusion of well-known single gene defects in individuals with an age >4 years and evidence of specific antibody deficiency. RESULTS: Detailed information on demographic data, survival rates, clinical phenotypes, immunologic and genetic data and treatment of 173 patients are provided. The early onset presentation (74.5%) and rate of consanguineous marriage (61.2%) were considerably higher in our cohort. Our study revealed clinically related correlations regarding consanguinity, the population of naïve CD4(+) T cells and switched-memory B cells, cytokine levels and special genetic factors (including HLA and AID genes). CONCLUSION: Despite current efforts, more comprehensive studies are needed, especially for classification and investigation of the genetic background and prognostic factors for patients with CVID in order to better managment and followup of patinets.

Using surface markers for MRI guided breast conserving surgery: a feasibility survey.

Breast MRI is frequently performed prior to breast conserving surgery in order to assess the location and extent of the lesion. Ideally, the surgeon should also be able to use the image information during surgery to guide the excision and this requires that the MR image is co-registered to conform to the patient's position on the operating table. Recent progress in MR imaging techniques has made it possible to obtain high quality images of the patient in the supine position which significantly reduces the complexity of the registration task. Surface markers placed on the breast during imaging can be located during surgery using an external tracking device and this information can be used to co-register the images to the patient. There remains the problem that in most clinical MR scanners the arm of the patient has to be placed parallel to the body whereas the arm is placed perpendicular to the patient during surgery. The aim of this study is to determine the accuracy of co-registration based on a surface marker approach and, in particular, to determine what effect the difference in a patient's arm position makes on the accuracy of tumour localization. Obtaining a second MRI of the patient where the patient's arm is perpendicular to body axes (operating room position) is not possible. Instead we obtain a secondary MRI scan where the patient's arm is above the patient's head to validate the registration. Five patients with enhancing lesions ranging from 1.5 to 80 cm(3) in size were imaged using contrast enhanced MRI with their arms in two positions. A thin-plate spline registration scheme was used to match these two configurations. The registration algorithm uses the surface markers only and does not employ the image intensities. Tumour outlines were segmented and centre of mass (COM) displacement and Dice measures of lesion overlap were calculated. The relationship between the number of markers used and the COM-displacement was also studied. The lesion COM-displacements ranged from 0.9 to 9.3 mm and the Dice overlap score ranged from 20% to 80%. The registration procedure took less than 1 min to run on a standard PC. Alignment of pre-surgical supine MR images to the patient using surface markers on the breast for co-registration therefore appears to be feasible.

A Gauss-Newton approach to joint image registration and intensity correction.

We develop a new efficient numerical methodology for automated simultaneous registration and intensity correction of images. The approach separates the intensity correction term from the images being registered in a regularized expression. Our formulation is consistent with the existing non-parametric image registration techniques, however, an extra additive intensity correction term is carried throughout. An objective functional is formed for which the corresponding Hessian and Jacobian is computed and employed in a multi-level Gauss-Newton minimization approach. In this paper, our experiments are based on elastic regularization on the transformation and total variation on the intensity correction. Validations on dynamic contrast enhanced MR abdominal images for both real and simulated data verified the efficacy of the model. The pursued approach is flexible in which we can exploit various forms of regularization on the transformation and the intensity correction.

Anatomical noise in contrast-enhanced digital mammography. Part I. Single-energy imaging.

PURPOSE: The use of an intravenously injected iodinated contrast agent could help increase the sensitivity of digital mammography by adding information on tumor angiogenesis. Two approaches have been made for clinical implementation of contrast-enhanced digital mammography (CEDM), namely, single-energy (SE) and dual-energy (DE) imaging. In each technique, pairs of mammograms are acquired, which are then subtracted with the intent to cancel the appearance of healthy breast tissue to permit sensitive detection and specific characterization of lesions. Patterns of contrast agent uptake in the healthy parenchyma, and uncanceled signal from background tissue create a "clutter" that can mask or mimic an enhancing lesion. This type of "anatomical noise" is often the limiting factor in lesion detection tasks, and thus, noise quantification may be useful for cascaded systems analysis of CEDM and for phantom development. In this work, the authors characterize the anatomical noise in CEDM clinical images and the authors evaluate the influence of the x-ray energy used for acquisition, the presence of iodine in the breast, and the timing of imaging postcontrast administration on anatomical noise. The results are presented in a two-part report, with SE CEDM described here, and DE CEDM in Part II. METHODS: A power law is used to model anatomical noise in CEDM images. The exponent, ß, which describes the anatomical structure, and the constant α, which represents the magnitude of the noise, are determined from Wiener spectra (WS) measurements on images. A total of 42 SE CEDM cases from two previous clinical pilot studies are assessed. The parameters α and ß are measured both from unprocessed images and from subtracted images. RESULTS: Consistent results were found between the two SE CEDM pilot studies, where a significant decrease in ß from a value of approximately 3.1 in the unprocessed images to between about 1.1 and 1.8 in the subtracted images was observed. Increasing the x-ray energy from that used in conventional DM to those of typical SE CEDM spectra with mean energies above 33 keV significantly decreased α by about a factor of 19, in agreement with theory. Compared to precontrast images, in the unprocessed postcontrast images at 30 s postinjection, α was larger by about 7.4 × 10(-7) mm(2) and ß was decreased by 0.2. While α did not vary significantly with the time after contrast administration, ß from the unprocessed image WS increased linearly, and ß from subtracted image WS increased with an initial quadratic relationship that plateaued by about 5 min postinjection. CONCLUSIONS: The presence of an iodinated contrast agent in the breast produced small, but significant changes in the power law parameters of unprocessed CEDM images compared to the precontrast images. Image subtraction in SE CEDM significantly reduced anatomical noise compared to conventional DM, with a reduction in both α and ß by about a factor of 2. The data presented here, and in Part II of this work, will be useful for modeling of CEDM backgrounds, for systems characterization and for lesion detectability experiments using models that account for anatomical noise.

A general PDE-framework for registration of contrast enhanced images.

This paper presents a general PDE-framework for registration of contrast enhanced images. The approach directly applies the idea of separating the contrast enhancement term from the images in the regularization terms. In our formulation, we stay consistent with existing non-parametric image registration techniques, however, we carry an additional contrast enhancement term throughout. A mathematically rigorous approach is pursued which can exploit various forms of regularization. In this paper, our experiments are built based on diffusion regularization for both contrast enhancement and the deformation field.