Radiographic Assessment of the Feline Temporomandibular Joint with Oblique Projections: A Preliminary Ex Vivo Study

Radiographic assessment of the temporomandibular joint in the domestic cat using conventional radiographic views can be challenging due to superimposition of overlying structures and the complex anatomy of the skull. The use of computed tomography, magnetic resonance imaging, and cone beam computed tomography to assess the temporomandibular joint in the cat has increased, but these modalities are not always available in general veterinary practices. Conventional radiography is still commonly used for first line assessment of the temporomandibular joint. The aim of this preliminary study was to determine optimal angle of obliquity of lateroventral-laterodorsal and laterorostral-laterocaudal (nose up lateral oblique) oblique radiographic views in the assessment of the temporomandibular joints in five feline mesaticephalic dry skulls. Visibility of the mandibular head, mandibular fossa, retroarticular process, and temporomandibular joint space were evaluated and scored by two veterinary radiologists. The results of this study identified that the dependent temporomandibular joint anatomy was best seen on the latero-10°-ventral-laterodorsal, latero-15°-ventral-laterodorsal, and latero-20°-ventral-laterodorsal, oblique views, and opposite lateral oblique views at these angulations may be helpful in characterization of this anatomy in clinical patients. The results also indicate that the laterorostral-laterocaudal (nose up lateral oblique) oblique view did not allow adequate discrimination of all TMJ anatomy at any angle, and is not recommended.

Prostatic artery embolization performed in anteroposterior projections versus steep oblique projections: single centre retrospective comparative analysis

Background To present and evaluate an approach for reduction of utilization of steep oblique angiographic projections during prostatic artery embolization (PAE). Methods Single-center, retrospective study of patients who underwent bilateral PAE (from October 2018 to November 2019) and in whom it was possible to embolize PA of at least one pelvic side utilizing anteroposterior projections only (AP-PAE group), with the following techniques: Identification of the origin of PA on anteroposterior angiographic views. Utilization of anatomic landmarks from the planning computed tomographic angiography. Distal advancement of the angiographic catheter or microcatheter in the anterior division of internal iliac artery. Gentle probing with microguidewire at the expected site of origin of the PA. The AP-PAE approach was initially applied to all PAE patients during the study period and when this approach failed, additional steep oblique projections were acquired; patients who underwent bilateral PAE, with both anteroposterior and oblique projections for both pelvic sides, formed the standard PAE (S-PAE) group. The AP-PAE group was compared with S-PAE group in terms of baseline clinical and anatomic features, technical/procedural aspects and outcomes. Results Forty-six patients (92 pelvic sides) were studied. AP-PAE was feasible in 12/46 patients (26.0%): unilateral AP-PAE in 9/46 patients (19.5%); bilateral AP-PAE in 3/46 patients (6.5%). AP-PAE group had larger prostates (p = 0.047) and larger PAs (p < 0.001). Body mass index (BMI) and other baseline features were comparable between the two groups (mean BMI, AP-PAE group: 27.9 ± 3.6, S-PAE group: 27.0 ± 3.5, p = 0.451). Mean fluoroscopy time and dose area product were lower in AP-PAE group (46.3 vs 57.9 min, p = 0.084 and 22,924.9 vs 35,800.4 μGy.m2, p = 0.018, respectively). Three months post PAE, comparable clinical success rates (11/12 vs 31/34, p = 0.959) and mean International Prostate Symptom Score reduction (60.2% vs 58.1%, p = 0.740) were observed for AP-PAE and for S-PAE group, respectively. No major complications were encountered. Conclusion AP-PAE is associated with significant reduction in radiation exposure and appears to be feasible, safe and effective, but it can be applied in a relatively small percentage of patients.

Use of a Method for Contour Analysis of Radiation Images of Malignant Breast Tumors on the Basis of Retrospective Material

Objective. To enhance the reliability of visual analysis of X-ray mammograms, by applying the mathematical models of neoplasms and a method for their processing based on the mathematical apparatus of contour analysis.Material and methods. Two data sets were generated from X-ray mammograms obtained from 38–82 year old patients at routine examinations in the Republican Oncology Dispensary. The first set contained 100 packages of X-ray mammographic images that failed to reveal abnormal malignant changes. The second set was represented by 168 packages of X-ray mammographic images showing morphologically verified breast cancer. All the packages of mammographic images are presented in the standard direct craniocaudal and mediolateral oblique projections. The images were obtained using an analog mammograph. Digital copies of images having a resolution of 600 dpi were obtained for subsequent computer processing. The latter of digital mammographic images involved segmentation of space-occupying lesions, determination of the linearity factor of their outlines, and differential diagnosis of space-occupying lesions based on the calculated value of the linearity factor of their outlines.Results. An algorithm was elaborated for identifying the outlines of space-occupying lesions on X-ray mammographic images. The sequence of complex-valued vectors approximating its curve was used as a mathematical model of the outline. The concept on the outline linearity factor, which quantitatively characterizes its shape, was introduced. A method was developed for the objective classification of malignant and benign space-occupying lesions based on the value of the introduced linearity factor. The outlines of benign space-occupying lesions in the breast were ascertained to be characterized by the higher linearity factor (in the region of 0.3–0.4) (BI-RADS category 2), while the outlines of malignant tumors had a much lower value of this factor (in the order of 0.05–0.1) (BI-RADS categories 4–5). The main quantitative measures (sensitivity, specificity, and accuracy) of the informative value of the proposed method were determined. The latter was shown to have a higher specificity than the traditional visual analysis carried out by a radiologist. This allows the proposed method to be used as an additional procedure in the visual analysis of mammograms to enhance the reliability of clinical findings.Conclusion. The practical value of the method is in quantitatively evaluating the shapes of malignant breast neoplasms, in reducing the performance of a mammographic examination, and in increasing its objectivity. The proposed method makes it possible to reduce the time of analyzing X-ray mammograms and to enhance the reliability of clinical findings.

On the class of (A,n) - real power positive operators in semi-hilbertian space

In this paper, the concept of the class of n-Real power positive operators on a hilbert space defined by Abdelkader Benali in [1] is generalized when an additional semi-inner product is considered. This new concept is described by means of oblique projections. For a Hilbert space operator T ∈ B(H) is (A,n) - Real power positive operators for some positive operator A and for some positive integer n ifTn + T#n ≥A 0, n = 1,2,...Keywords: Real power, Semi-Hilbertian space, Semi-inner product, Positive operators. 2000Mathematics Subject Classification: Primary 47B20. Secondary 47B99

MANAGEMENT OF LATERAL HUMERAL CONDYLAR FRACTURE IN CHILDREN

Analysis of literature related to treatment of children with humeral condyle fracture (HCF) showed that in 15–51% of cases the outcomes were unsatisfactory. Material and methods. Treatment experience of 486 children with acute HCF fractures aged 1 to 16 years is presented. The diagnostic uses additional oblique projections and computed tomography to detect the degree of dislocation and fragment mobility alongside with standard ultrasound examinations. Patients were distributed as follows considering the degree of HCF bone fragment dislocation: 170 (35%) patients with 1 degree of dislocation and 117 (24%) patients with 2 degree of dislocation, whereas 199 (41%) patients had 3 degree dislocation. Results. The patients were operated using the developed tactical scheme based on the suggested classification. It took into account both the degree of dislocation and fragment mobility in 1 degree fractures. Remote results were examined in 321 (66%) patients within 1–15 years after the trauma: the results were excellent in 278 (87%) cases, good in 29 (%) cases and satisfactory in 13 (4%) cases. Conclusions. Treatment of children with humeral condyle fractures was based on the differentiated approach to selection of treatment method depending on dislocation degree and mobility of a distal bone fragment.

Assessing the Effect of Packing the Sulcus on Image Quality in Equine Digital Radiography

The requirement to pack the sulcus of the equine foot as an aid to diagnostic interpretation before acquisition of dorsoproximal-palmarodistal oblique projections is debatable. The purpose of this study was to investigate the benefit of packing the sulcus in the assessment of normal anatomy. 23 cadaver limbs were radiographed in a podoblock (https://www.podoblock.com/products-page/podoblock/podoblock/). A non-packed image (NP) and a packed image (P) of the same foot were acquired. The image quality of P was graded against the reference NP by five observers, where −1=P was superior, 0=no difference between P and NP, and +1=NP was superior. Four anatomical criteria were used: the distal solar margin of the distal phalanx (DP), the vascular channels of DP, the palmar aspect of the distal interphalangeal joint and the articulation of the navicular bone with DP. A total Visual Grading Analysis Score of 0.28 indicates a preference for NP images. Packing was of benefit in only 10.8 per cent of cases. While judicious high-quality packing may be of benefit in a minority of cases, the routine packing of the sulcus in equine radiography was not found to be of benefit in the assessment of anatomical features in this study.

RADIATION DOSES TO ANAESTHETISTS DURING PROSTATIC ARTERY EMBOLIZATION INTERVENTIONAL PROCEDURES

The objective of this study was to assess the radiation doses received by anaesthetists from prostatic artery embolization (PAE) procedures. Ten PAE procedures conducted in a reference hospital in the city of Recife, Brazil were investigated. Occupational dosimetry was performed using thermoluminescent dosemeters which were located next to the eyes, close to the thyroid (over the shielding), on the thorax (under the apron), on the wrist and on the feet of the physician’s body. The results showed that the anaesthetist’s feet received the highest doses followed by the eyes and the hands. In some complex PAE procedures the doses received by anaesthetists on the lens of the eyes and the effective dose were higher than those received by the main operator due to the anaesthetist’s close position to the patient’s table and the use of oblique projections. The personal dose equivalent Hp(3) per procedure for the anaesthetist’s right eyebrow ranged from 20.2 μSv to 568.3 μSv. This result shows that anaesthetists assisting PAE procedures can exceeds the annual eye lens dose limit of 20 mSv recommended by the ICRP with only one procedure per week if radiation protection measures are not implemented during procedures.