Sciatic nerve fascicle differentiation on high-resolution ultrasound with histological verification: An ex vivo study.

INTRODUCTION/AIMS: The development of high-resolution ultrasound (HRUS) has enabled the depiction of peripheral nerve microanatomy in vivo. This study compared HRUS fascicle differentiation to the structural depiction in histological cross-sections (HCS). METHODS: A human cadaveric sciatic nerve was marked with 10 surgical sutures, and HRUS image acquisition was performed with a 22-MHz probe. The nerve was excised and cut into five segments for HCS preparation. Selected HCS were cross-referenced to HRUS, with sutures to improve orientation. Sciatic nerve and fascicle contouring were performed to assess nerve and fascicular cross-sectional area (CSA), fascicle count, and interfascicular distances. Three groups were defined based on HRUS fascicle differentiation in comparison to HCS, namely single fascicle (SF), fascicular cluster (FC), and no depiction (ND) group. RESULTS: On cross-referenced HRUS to HCS images, 58% of fascicles were differentiated. On HRUS, significantly larger fascicle CSA and smaller fascicle count were observed compared with HCS. Group analysis showed that 41% of fascicles were defined as SF, 47% as FC, and 12% as ND. The mean fascicle CSA in the ND group was 0.05 mm2. Compared with the SF, the FC had significantly larger fascicle CSA (1.2 ± 0.7 vs. 0.6 ± 0.4 mm2; p < .001) and shorter interfascicular distances (0.1 ± 0.04 vs. 0.5 ± 0.3 µm; p < .001). DISCUSSION: While HRUS can depict fascicular anatomy, only half of the fascicles visualized on HRUS directly correspond to single fascicles observed on HCS. The amount of interfascicular epineurium appears to influence the ability of HRUS to differentiate individual fascicles.

Skeletal muscle myosin heavy chain expression and 3D capillary network changes in streptozotocin-induced diabetic female mice.

It is not well-understood how type 1 diabetes (T1DM) affects skeletal muscle histological phenotype, particularly capillarisation. This study aimed to analyze skeletal muscle myosin heavy chain (MyHC) fibre type changes and 3D capillary network characteristics in experimental T1DM mice. Female C57BL/6J-OlaHsd mice were categorized into streptozotocin (STZ)-induced diabetic (n = 12) and age-matched non-diabetic controls (n =12). The muscle fibre phenotype of the soleus, gluteus maximus, and gastrocnemius muscles were characterized based on the expression of MyHC isoforms, while capillaries of the gluteus maximus were assessed with immunofluorescence staining, confocal laser microscopy and 3D image analysis. STZ-induced diabetic mice exhibited elevated glucose levels, reduced body weight, and prolonged thermal latency, verifying the T1DM phenotype. In both T1DM and non-diabetic mice, the gluteus maximus and gastrocnemius muscles predominantly expressed fast-twitch type 2b fibers, with no significant differences noted. However, the soleus muscle in non-diabetic mice had a greater proportion of type 2a fibers and comparable type 1 fiber densities (26.2 ± 14.6% vs 21.9 ± 13.5%) relative to diabetic mice. T1DM mice showed reduced fiber diameters (P = 0.026), and the 3D capillary network analysis indicated a higher capillary length per muscle volume in the gluteus maximus of diabetic mice compared to controls (P < 0.05). Overall, T1DM induced significant changes in the skeletal muscle, including shifts in MyHC fibre types, decreased fibre diameters, and increased relative capillarisation, possibly due to muscle fibre atrophy. Our findings emphasize the superior detail provided by the 3D analytical method for characterizing skeletal muscle capillary architecture, highlighting caution in interpreting 2D data for capillary changes in T1DM.

Ultrasound-guided hydrostatic reduction of intussusception: comparison of success rates between subspecialized pediatric radiologists and non-pediatric radiologists or radiology residents.

Ileocolic intussusception is the most common cause of intestinal obstruction in children under two years of age. Treatment in most cases is radiologically guided reduction. In Slovenia, ultrasound (US)-guided hydrostatic reduction is currently the standard of care. The purpose of this study was to compare the success rate of US-guided hydrostatic reduction when performed by subspecialty-trained pediatric radiologists, non-pediatric radiologists, or radiology residents. We retrospectively analyzed medical records of patients with ileocolic intussusception who underwent US-guided hydrostatic intussusception reduction at University Medical Centre Ljubljana between January 2012 and December 2022 (n = 101). During regular daily working hours, the reduction was performed by pediatric radiologists. After hours (evenings and overnight), pediatric radiologists, non-pediatric radiologists, or radiology residents performed the reduction procedure. Patients were divided into three groups based on the operator performing the procedure. Data was analyzed using the chi-square test. Pediatric radiologists had thirty-seven (75.5%) successful first attempts, non-pediatric radiologists had nineteen (76.0%), and radiology residents had twenty (74.1%). There was no statistically significant difference in the success rate of ileocolic intussusception reduction depending on the operator who performed the procedure (p = 0.98). No perforation was observed in either group during the reduction attempts.  Conclusion: Our results demonstrate that US-guided hydrostatic reduction is a reliable and safe procedure that achieves good results even in the hands of less experienced, however appropriately trained, radiologists. The results should encourage more medical centers to consider the implementation of US-guided hydrostatic reduction of ileocolic intussusception. What is Known: • US-guided hydrostatic reduction is a well-established method of treatment for ileocolic intussusception in children. • The results regarding the influence of operator's experience with the procedure on its success rate are scarce and contradictory. What is New: • US-guided hydrostatic intussusception reduction is a reliable and safe technique that achieves similar success rates when performed by experienced subspecialized pediatric radiologists or less experienced but trained operators such as non-pediatric radiologists and radiology residents. • The implementation of US-guided hydrostatic reduction in general hospitals without subspecialized pediatric radiologists could improve patient care by increasing access to radiologically guided reduction and simultaneously decreasing the time to reduction attempts.

Correlation between diffusion tensor indices and fascicular morphometric parameters of peripheral nerve.

Introduction: Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI) technique that measures the anisotropy of water diffusion. Clinical magnetic resonance imaging scanners enable visualization of the structural integrity of larger axonal bundles in the central nervous system and smaller structures like peripheral nerves; however, their resolution for the depiction of nerve fascicular morphology is limited. Accordingly, high-field strength MRI and strong magnetic field gradients are needed to depict the fascicular pattern. The study aimed to quantify diffusion tensor indices with high-field strength MRI within different anatomical compartments of the median nerve and determine if they correlate with nerve structure at the fascicular level. Methods: Three-dimensional pulsed gradient spin-echo (PGSE) imaging sequence in 19 different gradient directions and b value 1,150 s/mm2 was performed on a 9.4T wide-bore vertical superconducting magnet. Nine-millimeter-long segments of five median nerve samples were obtained from fresh cadavers and acquired in sixteen 0.625 mm thick slices. Each nerve sample had the fascicles, perineurium, and interfascicular epineurium segmented. The diffusion tensor was calculated from the region-average diffusion-weighted signals for all diffusion gradient directions. Subsequently, correlations between diffusion tensor indices of segmentations and nerve structure at the fascicular level (number of fascicles, fascicular ratio, and cross-sectional area of fascicles or nerve) were assessed. The acquired diffusion tensor imaging data was employed for display with trajectories and diffusion ellipsoids. Results: The nerve fascicles proved to be the most anisotropic nerve compartment with fractional anisotropy 0.44 ± 0.05. In the interfascicular epineurium, the diffusion was more prominent in orthogonal directions with fractional anisotropy 0.13 ± 0.02. Diffusion tensor indices within the fascicles and perineurium differed significantly between the subjects (p < 0.0001); however, there were no differences within the interfascicular epineurium (p ≥ 0.37). There were no correlations between diffusion tensor indices and nerve structure at the fascicular level (p ≥ 0.29). Conclusion: High-field strength MRI enabled the depiction of the anisotropic diffusion within the fascicles and perineurium. Diffusion tensor indices of the peripheral nerve did not correlate with nerve structure at the fascicular level. Future studies should investigate the relationship between diffusion tensor indices at the fascicular level and axon- and myelin-related parameters.

Sialendoscopy-Based Analysis of Submandibular Duct Papillae with a Proposal for Classification.

Identifying a submandibular (Wharton's) duct punctum often hinders sialendoscopy; however, there is a paucity of evidence on whether the appearance of Wharton's duct papilla impacts the sialendoscopic procedure. A classification of Wharton's duct papillae based on the macroscopic appearance, size of dilatation probes, and sialendoscopic approach was proposed herein. The classification describing four main types of papillae, A, B, C, and D, was prospectively evaluated on 351 Wharton's duct papillae in 315 patients. For each papillae type, the demographic/clinical data, intraoperative complications, and time required for sialendoscope introduction were analyzed. Estuary-like papilla (type A) was commonly seen after spontaneous stone extrusion, had no intraoperative complications noted, and had the shortest time required for the sialendoscope introduction. Normal papilla (type B) was the most frequently observed papilla (48.1%), reflecting diverse underlying pathology, while difficult papilla (type C) was often associated with unfavorable anatomical variations of the mandible or floor of the mouth. Substantially closed papilla (type D) had the highest rate of intraoperative complications, namely, perforation with a false passage, and required the longest time for the sialendoscope introduction. In seven patients (2.0%), the entrance into the duct was feasible only through the fistula, while the sialendoscope introduction failed in eight patients (2.3%). In conclusion, the appearance of Wharton's duct papillae may be influenced by the underlying pathology. Based on the proposed classification, papilla typology affects the duration of sialendoscope introduction and may influence the frequency of intraoperative complications.

Pharyngeal reconstruction after total laryngectomy with sliding epiglottis: technical aspects with retrospective review.

Introduction: Several techniques have been employed for defect reconstruction after total laryngectomy, among others sliding epiglottoplasty. As there is a paucity of data on sliding epiglottoplasty after total laryngectomy, this study aimed to present this reconstruction technique in detail with the retrospective analysis of the patients. Methods: We retrospectively reviewed single-center medical records of patients who underwent pharyngeal reconstruction after total laryngectomy between 2007-2013, with a follow-up to 2020. The study included patients who had total laryngectomy performed followed by a primary closure or sliding epiglottoplasty. The patients were divided according to the pharyngeal reconstruction technique: sliding epiglottis (n = 38) and primary closure (n = 120). Results: The baseline characteristics of patients, TNM stages, and previous treatment strategies did not differ significantly between the sliding epiglottis and primary closure group. The postoperative complication rates, including the pharyngocutaneous fistulae formation and strictures were comparable between the analyzed groups; however, a slightly higher incidence of pharyngocutaneus fistulae was noted within the patients after sliding epiglottoplasty. Overall 3-year survival of patients who underwent the epiglottoplasty and primary closure group were 73.7% vs. 57.5%, respectively. Conclusions: Sliding epiglottoplasty is considered a safe reconstruction technique. Although slightly better outcomes were noted within the epiglottoplasty group, it is still considered inferior to the primary closure. This technique ought to be considered in meticulously selected patients in whom primary closure is not feasible, epiglottis with nearby structures is spared from disease, and when the distal flaps are less appropriate or contraindicated.

Sialendoscopy in Management of Juvenile Recurrent Parotitis-A Single Centre Experience.

Juvenile recurrent parotitis is a rare inflammatory disease of the parotid gland that shares diverse therapeutic management between institutions. Sialendoscopy has been demonstrated as an efficient diagnostics and therapeutic method with minimal complications; however, due to the rarity of the disease and limited data, there is a lack of universal guidelines on its optimal management. Herein, we retrospectively analysed patients with juvenile recurrent parotitis who had the sialendoscopy performed at our tertiary centre. Descriptive data were retrieved along with the number of swelling episodes one year before and after the sialendoscopy intervention. In the last decade, twenty-nine sialendoscopic procedures were performed at our clinics on twenty-one patients diagnosed with juvenile recurrent parotitis. Most of them underwent the procedure under general anaesthesia (86%). In the year before and after the sialendoscopic procedure, the patients had 3.9 ± 2.7 and 0.2 ± 0.4 episodes of swelling per year, respectively. The difference proved to be statistically significant (p < 0.0001). The complete resolution was noted in sixteen patients (76%); however, the procedure was not repeated on the same side of any patient. Solely one patient had a relapse of the disease reported more than twelve months after the sialendoscopy, nonetheless, one of his exacerbation episodes was already reported in the first year after the sialendoscopy. The mean follow-up period of patients was 48.6 months (range, 13−116 months). All things considered, this study emphasises sialendoscopy as an effective minimally invasive diagnostic and therapeutic tool for the management of juvenile recurrent parotitis.

Reliability of haemophilia early arthropathy detection with ultrasound (HEAD-US) in children: a comparative magnetic resonance imaging (MRI) study.

BACKGROUND: Ultrasound (US) has been proven to be reliable in the assessment of early haemophilic arthropathy in the adult haemophilic population, however few studies so far focused on the reliability of US specifically in the paediatric haemophilic population. We were interested if the changing appearance of the growing bone hinders the ultrasonographic evaluation of the pathologic processes caused by haemophilic arthropathy. The aim of the study was to assess the reliability of US for evaluation of haemophilic arthropathy in children in comparison to magnetic resonance imaging (MRI). PATIENTS AND METHODS: The study included all children aged 6 years or more with severe haemophilia in the country (n = 10). We assessed their elbows, knees, and ankles bilaterally by US and compared the results to the MRI as the reference standard. Pearson correlation coefficient (r) was used to analyse correlation. RESULTS: The correlation with MRI for the US for the total score was excellent for all joints (r = 0.849 for the elbows, r = 1 for knees, r = 0.842 for ankles). The correlation of scores for specific joint components showed fair, moderate, or excellent correlation for all joint components in all joints. The correlation was the lowest for the evaluation of cartilage and bone in the ankles (r = 0.546 and r = 0.478) and bone in the elbows (r = 0.499). CONCLUSIONS: Our study proved that US using the HEAD-US method performed by paediatric radiologists is a reliable tool for detection and quantification of haemophilic arthropathy in children in comparison to MRI.

Contrast-Enhanced Ultrasound (CEUS) as an Ancillary Imaging Test for Confirmation of Brain Death in an Infant: A Case Report.

The practices for determining brain death are based on clinical criteria and vary immensely across countries. Cerebral angiography and perfusion scintigraphy are the most commonly used ancillary imaging tests for brain death confirmation in children; however, they both share similar shortcomings. Hence, contrast-enhanced ultrasound (CEUS) as a relatively inexpensive, easily accessible, and easy-to-perform technique has been proposed as an ancillary imaging test for brain death confirmation. CEUS has established itself as a favourable and widely used diagnostic imaging method in many different areas, but its application in delineating brain pathologies still necessities further validation. Herein, we present a case report of a 1-year-old polytraumatised patient in whom CEUS was applied as an ancillary imaging test for confirmation of brain death. As CEUS has not been validated as an ancillary test for brain death confirmation, the diagnosis was additionally confirmed with cerebral perfusion scintigraphy.

A Unique Case of Multicentric Infantile Myofibromatosis with Radiologic-Pathologic Correlation.

Infantile myofibromatosis (IM) is a rare condition with a variable clinical presentation that characteristically affects young children. Most frequently it presents as one or more benign nodules of the skin, bones, soft tissues, or, rarely, visceral organs. According to the location and number of lesions, there are three different forms: solitary, multicentric without visceral involvement, and multicentric with visceral involvement (generalised), with the latter having the least favourable prognosis. We present a unique case of severe congenital generalised IM in a new-born male who required intubation and mechanical ventilation immediately after the birth due to respiratory distress. A chest radiograph showed numerous tumours involving the entire lung, resembling a metastatic lung disease. Additionally, the neonate had multiple, bluish, papular skin nodules and a biopsy of a skin nodule ultimately led to the diagnosis of IM. Diffuse lung involvement prevented adequate ventilation which resulted in multiorgan failure and death before targeted treatment could have been initiated. The presented case is unique, as such atypical extensive involvement of the lung and leptomeninges in IM has not been reported before. In this brief report, we present the findings of radiographic and ultrasonographic examinations in correlation with autopsy and histopathology.