Typical CIDP, distal variant CIDP, and anti-MAG antibody neuropathy: An ultra-high frequency ultrasound comparison of nerve structure.

To date, little is known about the usefulness of ultra-high frequency ultrasound (UHF-US, 50-70 MHz) in clinical practice for the diagnosis of dysimmune neuropathies. We present a prospective study aimed at comparing UHF-US alterations of nerves and fascicles in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), distal CIDP (d-CIDP) and anti-MAG neuropathy and their relationships with clinical and electrodiagnostic (EDX) features. 28 patients were included (twelve CIDP, 6 d-CIDP and 10 anti-MAG) and ten healthy controls. Each patient underwent neurological examination, EDX and UHF-US study of median and ulnar nerves bilaterally. UHF-US was reliable in differentiating immune neuropathies from controls when using mean and/or segmental nerve and/or fascicle cross-sectional area (CSA); furthermore, fascicle ratio (fascicle/nerve CSA) was a reliable factor for differentiating d-CIDP from other types of polyneuropathies. The fascicle CSA appears to be more increased in CIDP and its variant than in anti-MAG neuropathy. UHF-US offers information beyond simple nerve CSA and allows for a better characterization of the different forms of dysimmune neuropathies.

Non-target embolic events during prostatic embolization with ethylene vinyl alcohol copolymer (EVOH).

BACKGROUND: This study evaluated nontarget embolization (NTE) during prostatic artery embolization (PAE) with ethylene vinyl alcohol copolymer (EVOH). RESULTS: Ten consecutive patients treated by PAE with EVOH for the presence of disabling benign prostatic hyperplasia (BPH)-related lower urinary tract symptoms (LUTS) between June 22 and January 2023 were included in this prospective study. The inclusion criteria were as follows: LUTS attributed to BPH, LUTS duration ≥ 6 months, failure to respond to standard pharmacotherapy, IPSS > 18 or QoL score > 2, and prostate volume > 40 mL. Embolization was performed under general anaesthesia. According to established techniques, a microcatheter was positioned bilaterally within the feeding arteries, and EVOH was injected slowly under X-ray control. Unenhanced pelvic computed tomography scans were carried out before and after embolization to assess the NTE. The safety of the prostatic embolization procedure with EVOH was assessed by collecting adverse effects over 3 months of evaluation that included the International Prostate Symptom Score (IPSS) and quality of life (QoL) score.-up evaluations, occurring at 3, 6, and 12months, included International Prostate Symptom Score. Bilateral PAE was technically successful in 9 patients, and unilateral injection was performed in one patient. The postoperative scanner showed a distribution of the embolization material in the two lobes of the prostate in all patients. The procedure time varied from 120 to 150 (mean: 132) minutes. Eight out of 10 patients developed pollakiuria within 24 h; none of the patients had postoperative pain. Two patients required catheterization for postoperative urinary retention. Catheters were removed successfully at the end of the first day for one of these patients and on the tenth day for the other. At the 3-month follow-up, patients showed significant improvement in the International Prostate Symptom Score (n = 10; mean = -11,5; P < 0.01) and quality of life score (n = 10; mean = -3,40; P < 0.01). Only one patient presented one asymptomatic muscular NTE. CONCLUSIONS: PAE with EVOH is safe, effective, and associated with few NTEs and no postoperative pain. Prospective comparative studies with longer follow-ups are warranted. TRIAL REGISTRATION: IDRCB, 2021-AO29-56-35. Registered 27 May 2022, http://clinicaltrials.gov/study/NCT05395299?cond=embolization&term&rank=1 .

Role of ultra-high-frequency ultrasound in the diagnosis and management of basal cell carcinoma: pilot study based on 117 cases.

BACKGROUND: Ultrasound imaging has recently benefited from the introduction of a new 70 MHz transducer able to provide high-resolution images, i.e. ultra-high-frequency ultrasound (UHFUS). AIM: To study the morphological features of basal cell carcinomas (BCCs) and measure BCC thickness by means of UHFUS examination. METHODS: In this retrospective multicentric study, 171 consecutive patients underwent UHFUS examination between November 2018 and May 2019 for suspected BCC. Diagnosis was confirmed by histopathology. A series of morphological parameters including echogenicity, structure, borders, shape composition (presence of intralesional structures) were investigated along with objective measurements such as thickness (maximum distance between the surface of the epidermis and the deepest part of the tumour) and width. RESULTS: In total, 117 BCCs from 93 patients were examined, including superficial (n = 13; 11.1%), nodular (n = 64; 54.7%), infiltrative (n = 18; 15.4%), mixed subtypes (n = 20; 17.1%) and other subtypes (n = 2; 1.7%). The most frequently observed UHFUS parameters included: hypoechoic signal (n = 80; 68.4%, P < 0.001), homogeneous structure (n = 76, 65.0%, P = 0.01), well-defined borders (n = 77, 65.8%, P < 0.001) and elongated shape (n = 71, 60.7%, P < 0.001). An excellent correlation was found between the BCC thickness measured by UHFUS and the value estimated by histology (interclass correlation ≥ 0.80). CONCLUSION: UHFUS is a new rapid and easy noninvasive skin imaging technique able to provide data on the dimensions and morphology of BCCs in real time and at the bedside. These characteristics mean UHFUS has a number of possible applications, ranging from presurgical mapping to the detection of disease recurrence and treatment monitoring.

Anatomical Variations of the Human Cochlea Using an Image Analysis Tool.

Understanding cochlear anatomy is crucial for developing less traumatic electrode arrays and insertion guidance for cochlear implantation. The human cochlea shows considerable variability in size and morphology. This study analyses 1000+ clinical temporal bone CT images using a web-based image analysis tool. Cochlear size and shape parameters were obtained to determine population statistics and perform regression and correlation analysis. The analysis revealed that cochlear morphology follows Gaussian distribution, while cochlear dimensions A and B are not well-correlated to each other. Additionally, dimension B is more correlated to duct lengths, the wrapping factor and volume than dimension A. The scala tympani size varies considerably among the population, with the size generally decreasing along insertion depth with dimensional jumps through the trajectory. The mean scala tympani radius was 0.32 mm near the 720° insertion angle. Inter-individual variability was four times that of intra-individual variation. On average, the dimensions of both ears are similar. However, statistically significant differences in clinical dimensions were observed between ears of the same patient, suggesting that size and shape are not the same. Harnessing deep learning-based, automated image analysis tools, our results yielded important insights into cochlear morphology and implant development, helping to reduce insertion trauma and preserving residual hearing.

Bayesian logistic shape model inference: Application to cochlear image segmentation.

Incorporating shape information is essential for the delineation of many organs and anatomical structures in medical images. While previous work has mainly focused on parametric spatial transformations applied to reference template shapes, in this paper, we address the Bayesian inference of parametric shape models for segmenting medical images with the objective of providing interpretable results. The proposed framework defines a likelihood appearance probability and a prior label probability based on a generic shape function through a logistic function. A reference length parameter defined in the sigmoid controls the trade-off between shape and appearance information. The inference of shape parameters is performed within an Expectation-Maximisation approach in which a Gauss-Newton optimization stage provides an approximation of the posterior probability of the shape parameters. This framework is applied to the segmentation of cochlear structures from clinical CT images constrained by a 10-parameter shape model. It is evaluated on three different datasets, one of which includes more than 200 patient images. The results show performances comparable to supervised methods and better than previously proposed unsupervised ones. It also enables an analysis of parameter distributions and the quantification of segmentation uncertainty, including the effect of the shape model.

Inner-ear augmented metal artifact reduction with simulation-based 3D generative adversarial networks.

Metal Artifacts creates often difficulties for a high quality visual assessment of post-operative imaging in computed tomography (CT). A vast body of methods have been proposed to tackle this issue, but these methods were designed for regular CT scans and their performance is usually insufficient when imaging tiny implants. In the context of post-operative high-resolution CT imaging, we propose a 3D metal artifact reduction algorithm based on a generative adversarial neural network. It is based on the simulation of physically realistic CT metal artifacts created by cochlea implant electrodes on preoperative images. The generated images serve to train a 3D generative adversarial networks for artifacts reduction. The proposed approach was assessed qualitatively and quantitatively on clinical conventional and cone beam CT of cochlear implant postoperative images. These experiments show that the proposed method outperforms other general metal artifact reduction approaches.

Ultra-high-frequency ultrasound imaging of sural nerve: A comparative study with nerve biopsy in progressive neuropathies.

INTRODUCTION: Nerve ultrasound has been used increasingly in clinical practice as a complementary test for diagnostic assessment of neuropathies, but nerve biopsy remains invaluable in certain cases. The aim of this study was to compare ultra-high-frequency ultrasound (UHF-US) to histologic findings in progressive polyneuropathies. METHODS: Ten patients with severe, progressive neuropathies underwent ultrasound evaluation of the sural nerve before nerve biopsy. Ultrasound data were compared with histologic results in a retrospective manner. RESULTS: Sural nerves were easily identified on UHF-US. Nerve hyperechogenicity correlated with inflammatory infiltrates on biopsy. Nerve fascicles could be identified and measured on ultrasound in the majority of patients. DISCUSSION: Hyperechogenicity on UHF-US may be a marker of nerve inflammation in neuropathies. Furthermore, the UHF-US probe allows for evaluation of sensory nerves in spite of their small size, providing valuable information on their size and on their internal structure.

Visceral fat is associated to the severity of COVID-19.

BACKGROUND: Excess visceral fat (VF) or high body mass index (BMI) is risk factors for severe COVID-19. The receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is expressed at higher levels in the VF than in the subcutaneous fat (SCF) of obese patients. AIM: To show that visceral fat accumulation better predicts severity of COVID-19 outcome compared to either SCF amounts or BMI. METHODS: We selected patients with symptomatic COVID-19 and a computed tomography (CT) scan. Severe COVID-19 was defined as requirement for mechanical ventilation or death. Fat depots were quantified on abdominal CT scan slices and the measurements were correlated with the clinical outcomes. ACE 2 mRNA levels were quantified in fat depots of a separate group of non-COVID-19 subjects using RT-qPCR. RESULTS: Among 165 patients with a mean BMI of 26.1 ±â€¯5.4 kg/m2, VF was associated with severe COVID-19 (p = 0.022) and SCF was not (p = 0.640). Subcutaneous fat was not different in patients with mild or severe COVID-19 and the SCF/VF ratio was lower in patients with severe COVID-19 (p = 0.010). The best predictive value for severe COVID-19 was found for a VF area ≥128.5 cm2 (ROC curve), which was independently associated with COVID-19 severity (p < 0.001). In an exploratory analysis, ACE 2 mRNA positively correlated with BMI in VF but not in SCF of non-COVID-19 patients (r2 = 0.27 vs 0.0008). CONCLUSION: Severe forms of COVID-19 are associated with high visceral adiposity in European adults. On the basis of an exploratory analysis ACE 2 in the visceral fat may be a trigger for the cytokine storm, and this needs to be clarified by future studies.

Sonoelastography to Assess Muscular Stiffness Among Older Adults and its Use for the Diagnosis of Sarcopenia: A Systematic Review.

Changes in muscle stiffness have been reported with sarcopenia. Sonoelastography is an accessible and non-radiating imaging technique allowing quantification of elastic properties of tissue. We performed a systematic review of the literature to investigate whether sonoelastography can be a reliable method to assess sarcopenia in older patients. We searched Medline, Google Scholar, Scopus, SpringerLink and Science direct from January 1, 1990 to April 1, 2020. Three independent review authors assessed trial eligibility, extracted the data, and assessed risk of bias. We intended to learn which types of elastography have been tested, if such measures are repeatable, and if they have been compared to the currently accepted diagnostic method. Ten studies met the inclusion criteria. Most followed a cross-sectional design with young and older adult subgroups. The gastrocnemius, rectus femoris, and vastus intermedius appeared most frequently. Nine of the included studies used shear wave elastography and one-strain elastography. The passive elastic constant was significantly greater in sarcopenic versus healthy subjects after passive stretching (124.98 ±â€Š60.82 vs. 46.35 ± 15.85, P = 0.004). However, even in non-sarcopenic patients, the age of the patient was responsible for about 45.5 % of the variance in SWV. Among ten included articles, four reported higher stiffness in the muscles of older adults, two reported lower stiffness, and four found no significant difference. Due to the substantial heterogenicity of actual data, we could not make any conclusions about the potential usefulness of elastography to assess sarcopenia. Further studies are needed, including a larger sample of older patients and using a standardized and reproducible protocol.

Ultrasound-guided percutaneous release of the carpal tunnel: comparison of the learning curves of a senior versus a junior operator. A cadaveric study.

OBJECTIVE: The purpose was to evaluate, in a cadaveric cohort, the feasibility and the learning curve of ultrasound-guided percutaneous carpal tunnel release. MATERIALS AND METHODS: Fourteen carpal tunnel releases were carried out on unembalmed cadavers by a senior and a junior radiologist. Procedures were realized with an 18-MHz linear probe. An anatomical evaluation was first performed using ultrasound to detect any anatomical variant. After hydrodissection of the carpal tunnel with lidocaine, a 3-mm hook knife was introduced into the security zone to perform a retrograde section of the transverse carpal ligament (TCL) under ultrasound guidance. Anatomical dissection was performed for each wrist. The main evaluation criterion was the complete TCL section. The procedure duration (minutes), skin incision size (millimeters), the integrity of the median nerve, thenar motor branch, and palmar vascular arch were also evaluated. RESULTS: The senior operator was able to perform a complete release after training on three specimens and the junior operator after four specimens (p > 0.05). In most of the cases when complete release was not achieved, it was due to an incomplete section of the distal TCL (10 mm missing section on average). Mean duration time of procedure was 14 min (11 min for the senior versus 17 min for the junior, p > 0.05). Damage of neither the median nerve nor the vascular structure was observed. Mean size of the skin incision was 3 mm. CONCLUSION: The ultrasound-guided percutaneous release of the carpal tunnel is demonstrated to be a procedure with a rapid learning curve.

Motor cortex neurovascular coupling: inputs from ultra-high-frequency ultrasound imaging in humans.

OBJECTIVE: Neurovascular coupling reflects the link between neural activity and changes in cerebral blood flow. Despite many technical advances in functional exploration of the brain, including functional MRI, there are only a few reports of direct evidence of neurovascular coupling in humans. The authors aimed to explore, for the first time in humans, the local cerebral blood flow of the primary motor cortex using ultra-high-frequency ultrasound (UHF-US) Doppler imaging to detect low blood flow velocity (1 mm/sec). METHODS: Four consecutive patients underwent awake craniotomy for glioma resection using cortical direct electrostimulation for brain mapping. The primary motor cortical area eliciting flexion of the contralateral forearm was identified. UHF-US color Doppler imaging of this cortical area was acquired at rest, during repeated spontaneous forearm flexion, and immediately after the movement's termination. In each condition, the surface areas of the detectable vessels were measured after extraction of non-zero-velocity colored pixels and summed. RESULTS: During movement, local cerebral blood flow increased significantly by 14.4% (range 5%-30%) compared with baseline. Immediately after the termination of movements, the local hyperemia decreased significantly by 8.6% (range 1.9%-15.7%). CONCLUSIONS: To the authors' knowledge, this study is the first to provide a real-time demonstration of the neurovascular coupling in the human cortex by ultrasound imaging. They assume that UHF-US may be used to gather original and advanced data on brain functioning, which could be used to help in the identification of functional cortical areas during brain surgery.Clinical trial registration no.: NCT03179176 (clinicaltrials.gov).

Automated analysis of human cochlea shape variability from segmented µCT images.

The aim of this study is to define an automated and reproducible framework for cochlear anatomical analysis from high-resolution segmented images and to provide a comprehensive and objective shape variability study suitable for cochlear implant design and surgery planning. For the scala tympani (ST), the scala vestibuli (SV) and the whole cochlea, the variability of the arc lengths and the radial and longitudinal components of the lateral, central and modiolar paths are studied. The robustness of the automated cochlear coordinate system estimation is validated with synthetic and real data. Cochlear cross-sections are statistically analyzed using area, height and width measurements. The cross-section tilt angle is objectively measured and this data documents a significant feature for occurrence of surgical trauma.

Perirenal fat thickness measured with computed tomography is a reliable estimate of perirenal fat mass.

Deposition of perirenal adipose tissue has been associated with adverse renal and cardiovascular events. We compared various methods to measure perirenal adipose tissue using computerized tomography (CT)-scan and performed correlations with anthropometric measures associated with renal and cardiovascular events. Voluntary overweight and obese subjects undergoing a CT-scan for diagnostic purposes were included in the study. Perirenal adipose tissue volume, adipose tissue area of the renal sinus and perirenal fat thickness were manually measured bilaterally. The intra- and inter-observer coefficient correlations and the correlation between the diverse measures of renal adipose tissue, subcutaneous (SC-)fat and anthropometrics measures were analyzed using Pearson's correlation tests. The forty included patients (24 men, 16 women) had a mean age of 57.6 ± 18.1 years and a mean body mass index of 28.9 ± 2.9 kg/m2. Despite comparable waist circumference, women had a greater SC-fat thickness compared to men, and therefore a smaller amount of visceral fat, as well as smaller perirenal fat volumes. Perirenal fat thickness was better correlated with perirenal fat volume than adipose area of the renal sinus (p <0.02). The adipose area of the renal sinus did not correlate with any anthropometric measures. In women, perirenal fat volume and thickness showed a negative correlation with SC-fat thickness and no correlation with waist circumference. In men, perirenal fat volume and thickness showed a positive correlation with waist circumference and no correlation with subcutaneous fat thickness. In conclusion, perirenal fat thickness measured with CT-scan at the level of the renal veins is a simple and reliable estimate of perirenal fat volume, that correlated negatively with SC-fat in women and positively with waist circumference in men. The adipose area of the renal sinus did not correlate with any anthropometric measure.

Impact of the surgical experience on cochleostomy location: a comparative temporal bone study between endaural and posterior tympanotomy approaches for cochlear implantation.

The goal of this study was to evaluate, in the hands of an inexperienced surgeon, the cochleostomy location of an endaural approach (MINV) compared to the conventional posterior tympanotomy (MPT) approach. Since 2010, we use in the ENT department of Nice a new surgical endaural approach to perform cochlear implantation. In the hands of an inexperienced surgeon, the position of the cochleostomy has not yet been studied in detail for this technique. This is a prospective study of 24 human heads. Straight electrode arrays were implanted by an inexperienced surgeon: on one side using MPT and on the other side using MINV. The cochleostomies were all antero-inferior, but they were performed through an endaural approach with the MINV or a posterior tympanotomy approach with the MPT. The positioning of the cochleostomies into the scala tympani was evaluated by microdissection. Cochleostomies performed through the endaural approach were well placed into the scala tympani more frequently than those performed through the posterior tympanotomy approach (87.5 and 16.7 %, respectively, p ≤ 0.001). This study highlights the biggest challenge for an inexperienced surgeon to achieve a reliable cochleostomy through a posterior tympanotomy, which requires years of experience. In case of an uncomfortable view through a posterior tympanotomy, an inexperienced surgeon might be able to successfully perform a cochleostomy through an endaural (combined approach) or an extended round window approach in order to avoid opening the scala vestibuli.

Necrotizing otitis externa: a systematic review.

OBJECTIVE: To carry out a systematic review of scientific evidence available about necrotizing otitis externa, emphasizing epidemiologic data, diagnosis criteria, treatment protocols, follow-up criteria, prognosis factors, and chronologic evolution. DATA SOURCES: PubMed/MEDLINE and the Cochrane Database of Systematic Reviews were searched for publications in English and French languages, between 1968 and October 1, 2011. STUDY SELECTION: We included publications of all types including at least 6 cases. We excluded publications focused on cranial base osteomyelitis not originating from the external ear and publications limited to a specific population. DATA EXTRACTION: We assessed publication quality according to international guidelines. DATA SYNTHESIS: For each publication, data were entered in a spreadsheet software for analysis. We excluded individual data already published in other studies or reviews. CONCLUSION: Our review revealed the absence of strong scientific evidence regarding diagnosis criteria, treatment protocols and follow-up criteria. This implies the use of highly empirical indexes of suspicion in clinical practice. Our review confirmed the existence of a typical but not exclusive population at risk (aged, male, and diabetic patient) and also revealed major issues: lack of primary prevention in population at risk, delays before referral and management, bacteriologic issues caused by antibiotic misuse (agent identification problems, rise of resistant strains), persistence of recurrent cases. A better diffusion of medical information should help improve the management of this severe disease.

Primary cough headache, primary exertional headache, and primary headache associated with sexual activity: a clinical and radiological study.

INTRODUCTION: The purposes of this study are to describe clinical features of primary cough headache, primary exertional headache, and primary headache associated with sexual activity and to evaluate potential association with abnormalities in the cerebral or cervical venous circulation. METHODS: This multicentre, observational, non-interventional consecutive cohort study included patients fulfilling ICHD-II criteria for primary cough headache (N = 10), primary exertional headache (N = 11), or primary headache associated with sexual activity (N = 20), as well as 16 headache-free controls. Each patient was evaluated clinically and underwent craniocervical MRV of the cranial circulation. All scans were interpreted centrally by blinded raters, using the Farb criteria proposed for idiopathic intracranial hypertension. Stenosis was defined as a Farb score <3 in left or right transverse sinuses or jugular veins. RESULTS: In all primary headache groups, headaches were most frequently diffuse, severe, or very severe. Headache duration was significantly shorter in patients with cough headache (median 6.5 versus 20 and 60 min). An exploitable magnetic resonance venogram was obtained for 36 patients. Stenosis was detected in none of the control group, but in 5/7 patients with primary cough headache group, 2/10 patients with primary exertion headache, and 12/19 patients with primary headache associated with sexual activity. The frequency of stenosis was significantly different from the control group in the primary cough headache and primary headache associated with sexual activity groups. CONCLUSIONS: Headaches provoked by cough and sexual activity are possibly associated with venous abnormalities in a significant subgroup of affected patients. As the literature shows conflicting results, this venous stenosis can be considered as a promoting factor.

Endovascular treatment of a wide-neck renal artery bifurcation aneurysm.

Wide-neck renal artery aneurysms are difficult or impossible to treat endovascularly with Guglielmi detachable coils. The authors report a case of embolization of a wide-neck aneurysm of the right renal artery bifurcation with the combination of a TrisPan coil (neck-bridge device developed by Boston Scientific Target) and Guglielmi detachable coils. Complete occlusion of the aneurysm with preservation of the renal artery and its branches was shown with angiography performed after the procedure.

[Persistent hematuria after embolization for hemorrhagic complication following percutaneous nephrolithotomy: value of the study of red blood cell volume in urine]. / Hématurie persistante après embolisation pour complication hémorragique d'une néphrolitotomie percutanée: intérêt de l'étude du volume des globules rouges dans les urines.

Percutaneous nephrolithotomy is associated with a high risk of complications, particularly bleeding, which makes it a potentially invasive technique. Management of haemorrhagic complications sometimes requires the use of embolization. Recurrence after embolization can occur as a result of revascularization or recanalization of vessels, but post-embolization infarction can also lead to persistent haematuria. The authors report the clinical case of a 36-year-old patient presenting with recurrence of severe haematuria after two successive highly selective embolizations. Analysis of the mean corpuscular volume of red cells in the urine confirmed the parenchymal and non-vascular origin of the bleeding, corresponding to a post-embolization syndrome. This analysis therefore constitutes a simple way to avoid repeated embolization or surgical exploration.