Marco Barillari

Predictors of Ectopic Fat Accumulation in Liver and Pancreas in Obese Men and Women

The aim of the present study was to determine the relationship between body fat distribution, adipocytokines, inflammatory markers, fat intake and ectopic fat content of liver and pancreas in obese men and women. A total of 12 lean subjects (mean age 47.25 ± 14.88 years and mean BMI 22.85 ± 2), 38 obese subjects (18 men and 20 women) with mean age 49.1 ± 13.0 years and mean BMI 34.96 ± 4.21 kg/m2 were studied. Measurements: weight, height, BMI, waist circumference, as well as glucose, insulin, HOMA (homeostasis model assessment of insulin resistance), cholesterol, triglycerides, high‐density lipoprotein cholesterol, high sensitivity C‐reactive protein, daily energy intake, leptin, and adiponectin. Magnetic resonance was used to evaluate visceral, subcutaneous adipose tissue (SCAT) as well as liver and pancreas lipid content using in‐phase and out‐of‐phase magnetic resonance imaging (MRI) sequence. Obese subjects had significantly higher weight, waist circumference, SCAT, deep SCAT, visceral adipose tissue (VAT), liver and pancreatic lipid content than lean subjects. Obese women had significantly lower VAT, liver and pancreas lipid content regardless of same BMI. In multiple regression analyses, the variance of liver lipid content explained by gender and VAT was 46%. When HOMA was added into a multiple regression, a small increase in the proportion of variance explained was observed. A 59.2% of the variance of pancreas lipid content was explained by gender and VAT. In conclusion, obese men show higher VAT and ectopic fat deposition in liver and pancreas than obese women despite same BMI. Independent of overall adiposity, insulin resistance, adiponectin and fat intake, VAT, measured with MRI, is the main predictor of ectopic fat deposition in both liver and pancreas.

Radiation dose saving through the use of cone-beam CT in hearing-impaired patients

PurposeBionic ear implants provide a solution for deafness. Patients treated with these hearing devices are often children who require close follow-up with frequent functional and radiological examinations; in particular, multislice computed tomography (MSCT). Dental volumetric cone-beam CT (CBCT) has been reported as a reliable technique for acquiring images of the temporal bone while delivering low radiation doses and containing costs. The aim of this study was to assess, in terms of radiation dose and image quality, the possibility of using CBCT as an alternative to MSCT in patients with bionic ear implants.Materials and methodsOne hundred patients (mean age 26 years, range 7–43) with Vibrant SoundBridge implants on the round window underwent follow-up: 85 with CBCT and 15 with MSCT. We measured the average tissue-absorbed doses during both MSCT and CBCT scans. Each scan was focused on the temporal bone with the smallest field of view and a low-dose protocol. In order to estimate image quality, we obtained data about slice thickness, high- and low-contrast resolution, uniformity and noise by using an AAPM CT performance phantom.ResultsAlthough the CBCT images were qualitatively inferior to those of MSCT, they were sufficiently diagnostic to allow evaluation of the position of the implants. The effective dose of MSCT was almost three times higher than that of CBCT.ConclusionsOwing to low radiation dose and sufficient image quality, CBCT could be considered an adequate technique for postoperative imaging and follow-up of patients with bionic ear implants.RiassuntoObiettivoGli impianti bionici all’orecchio rappresentano una soluzione contro la sordità. I pazienti trattati con questi tipi di ausili, spesso bambini, necessitano di un follow-up di esami sia funzionali che radiologici, in particolare mediante tomografia computerizzata multistrato (MSTC). La TC volumetrica dentale a fascio conico (CBCT) è una metodica utile allo studio dell’osso temporale, con il vantaggio di erogare basse dosi di radiazioni ionizzanti e di avere costi di gestione contenuti. Lo scopo dello studio è di valutare la CBCT in termini di dose radiante e di qualità d’immagine: il suo eventuale impiego in alternativa alla MSTC (con il protocollo attualmente utilizzato) comporterebbe infatti una sostanziale riduzione della dose ai pazienti con orecchio bionico.Materiali e metodiSono stati inclusi 100 pazienti ipoacusici (età media 26 anni, range 7–43), trattati mediante protesi Vibrant SoundBridge alla finestra rotonda, 15 studiati in follow-up mediante TC e 85 mediante CBCT, calcolando le dosi medie assorbite per tessuto sia durante esame MSTC che CBCT: ogni studio era focalizzato sull’osso temporale utilizzando il più piccolo campo di vista ed il protocollo a bassa dose radiante. Per la stima della qualità dell’immagine, sono stati ottenuti i valori di spessore di strato, risoluzione ad alto e basso contrasto e uniformità/rumore mediante l’uso di fantoccio AAPM CT performance.RisultatiLe immagini ottenute con la CBCT sono di qualità inferiore rispetto alla MSTC, ma sufficientemente diagnostiche, permettendo di valutare con sicurezza la posizione delle estremità degli impianti acustici. La dose efficace della MSTC è risultata circa tre volte superiore rispetto a quella della CBCT.ConclusioniLa CBCT, grazie alla bassa dose impartita e alla sufficiente qualità delle immagini, può essere considerata tecnica radiologica adeguata per i controlli postoperatori ed il follow-up dei pazienti con orecchio bionico.

Imaging in 28 children with cochlear nerve aplasia

Conclusion. Preoperative CT and MRI assessment of children with severe or profound sensorineural hearing loss (SNHL) is critical for determining implant candidacy. Objectives. There are a significant number of children who do not show any auditory development with a cochlear implant (CI), possibly due to cochlear nerve (CN) aplasia/hypoplasia. Regardless of the suspected etiology, if a CI is not providing auditory development the clinician should carefully evaluate the possibility of a CN malformation and re-evaluate the child with detailed neuroimaging studies. If the imaging evaluation shows severe cochlear malformation or CN aplasia there is some developmental urgency to consider auditory brainstem implant (ABI) surgery. Subjects and methods. Twenty-eight children affected by congenital SNHL were examined by CT and MRI. Evaluation of the cerebellopontine angle (CPA), internal auditory canal (IAC), cranial nerves, and membranous labyrinth was performed. Six children had been previously fitted elsewhere with a CI with no sound detection. Results. Suspected congenital anomalies were confirmed by CT and MRI in all 28 children: 16 with associated labyrinthine malformations; 1 with outer, middle, and inner ear malformations; and 2 with associated monolateral facial nerve aplasia.

Congenital aural atresia treated with floating mass transducer on the round window: 5 years of imaging experience

PurposeThe aim of this paper is to illustrate imaging features of patients affected by congenital aural atresia (CAA) before and after treatment with a Vibrant SoundBridge (VSB) device implanted on the round window.Materials and methodsTen patients (5 males and 5 females; mean age 22.1 years) with CAA underwent preoperative high-resolution computed tomography (HRCT) to estimate the degree of involvement of the middle- and inner-ear structures and highlight radiological landmarks useful for surgical planning.ResultsBilateral CAA, mostly of the mixed type, was present in 7 patients and ossicular chain abnormalities in 16 ears (94% of cases). The round window region was normal in all patients, whereas facial-nerve course and/or caliber abnormalities were present in 6 ears (35.3%). The tympanic cavity was small in 13 ears (76.5%), whereas the mastoid was well pneumatized in 8/17 (47%).ConclusionsHRCT provides accurate information about anatomy and malformations of the middle and inner ear and can thus assist the surgeon in planning the procedure.RiassuntoObiettivoLo scopo di questo studio è di descrivere le caratteristiche radiologiche pre-operatorie e postoperatorie dei pazienti affetti da atresia congenita aurale (ACA) impiantati mediante Vibrant SoundBridge (VSB) alla finestra rotonda.Materiali e metodiDieci pazienti (5 maschi e 5 femmine; età media: 22,1 anni) con ACA sono stati sottoposti ad un esame di tomografia computerizzata (TC) ad alta risoluzione per stimare il grado di coinvolgimento delle strutture dell’orecchio medio ed interno ed evidenziare utili punti di riferimento per l’intervento.RisultatiSono state riscontrate atresia bilaterale in 7 pazienti, prevalentemente di tipo misto, ed anomalie della catena ossiculare in 16 orecchi (94% dei casi). La finestra rotonda era nei limiti in tutti i soggetti, mentre in 6 orecchi (35,3%) erano presenti anomalie di decorso e/o di calibro del nervo faciale. La cassa timpanica era ipoplasica in 13 orecchi (76,5%), mentre la mastoide era ben pneumatizzata in 8/17 (47%).ConclusioniLa TC ad alta risoluzione fornisce le corrette informazioni circa l’anatomia e le malformazioni dell’orecchio medio ed interno, utili per il chirurgo per la programmazione operatoria.

Bionic ear imaging.

PurposeThe aim of this study was to illustrate the different imaging features of middle and inner ear implants, brainstem implants and inferior colliculus implants.Materials and methodsWe retrospectively reviewed the computed tomography (CT) images of 468 patients with congenital or acquired transmissive or neurosensory hearing loss who underwent surgery. The implants examined were: 22 Vibrant Soundbridge implants, 5 at the long limb of the incus and 17 at the round window, 350 cochlear implants, 95 brainstem implants and 1 implant at the inferior colliculus. All patients underwent a postoperative CT scan (single or multislice scanner) and/or a Dentomaxillofacial cone-beam CT scan (CBCT) (axial and multiplanar reconstruction), and/or a plain-film radiography to visualise the correct position of the implant.ResultsThe CBCT scan depicts Vibrant site of implant better than plain-film radiography, with a lower radiation dose compared to CT. For cochlear implants, a single plain radiograph in the Stenvers projection can directly visualise the electrodes in the cochlea. All patients with brainstem or inferior colliculus implants underwent postoperative CT to exclude complications and the assess correct implantation, but the follow-up of these implants can be performed by plain radiography alone.ConclusionsCT and CBCT scans are reliable and relatively fast methods for precisely determining the location of middle ear implants. CBCT is preferable to CT because of the lower radiation dose administered; a single plain-film radiograph is enough to visualise and follow-up cochlear, brainstem and inferior colliculus implants.RiassuntoObiettivoIllustrare le caratteristiche delle diverse tecniche impiegate nell’imaging degli impianti protesici all’orecchio medio e interno, degli impianti al tronco encefalico ed al collicolo inferiore.Materiali e metodiSono state analizzate retrospettivamente le immagini di tomografia computerizzata (TC) di 468 pazienti affetti da ipoacusia congenita o acquisita trasmissiva o neurosensoriale, sottoposti a intervento chirurgico protesico. I modelli di impianto esaminati sono stati: 22 Vibrant, di cui 5 all’apofisi lunga dell’incudine e 17 alla finestra rotonda, 350 impianti cocleari, 95 impianti al tronco e 1 al collicolo inferiore. Tutti i pazienti hanno eseguito nel postoperatorio una indagine TC (scanner a singolo o multistrato) e/o una TC dentale a raggio conico (TCD) (ricostruzioni assiali e multiplanari), e/o una radiografia convenzionale, al fine di visualizzare la corretta posizione dell’impianto.RisultatiLe scansioni TCD hanno identificato meglio il sito di impianto del Vibrant rispetto alla radiografia convenzionale: la visualizzazione è uguale a quella della TC ma la dose radiante è inferiore. Per gli impianti cocleari, la radiografia in proiezione secondo Stenvers ha consentito di visualizzare direttamente gli elettrodi nella coclea in tutti i casi. Tutti i pazienti con impianto al tronco o al collicolo inferiore sono stati sottoposti a indagine TC nell’immediato postoperatorio al fine di escludere complicanze e per stimare il corretto posizionamento della protesi, ma il follow-up di queste ultime può essere eseguito con la sola radiografia del cranio.ConclusioniLa TC e la TCD si sono rivelate metodiche affidabili e relativamente veloci per determinare con precisione la posizione dell’impianto all’orecchio medio. La TCD è preferibile alla TC per la minor dose radiante somministrata; la sola radiografia del cranio, è sufficiente per visualizzare gli impianti cocleari, al tronco ed al collicolo inferiore, e per effettuarne il follow-up.

Evidence of Gadolinium Distribution from the Endolymphatic Sac to the Endolymphatic Compartments of the Human Inner Ear

To verify whether injection of substances into the endolymphatic sac (ES) diffuses into the endolymphatic compartments of the human inner ear and in particular to the endolymphatic space of the scala media (ESp-SM), as demonstrated in animals, an exploratory investigation with magnetic resonance imaging (MRI) and intraoperative electrocochleographic recordings (ECoG) was conducted in patients with Ménière’s disease (MD) treated with ES decompression. A mixture of dexamethasone and gadolinium (GD) in solution was injected into the ES of 4 patients. The results of the ES injection procedure were compared with administration of the same solution intratympanically (IT, 1 patient) and via a platinotomy in 2 patients. The study was conducted retrospectively at a tertiary referral center. Main outcomes measures were pre- and postintervention complete audiological and neuro-otological evaluation; intraoperative ECoG investigation with evaluation of the morphology of acoustically elicited compound action potentials (CAPs) and 1.5 T MRI evaluations at different follow-up times. Distribution of GD from the ES injection procedure was observed first in the ES, after 24 h in the vestibule and semicircular canals, and after 24–48 h in the ESp-SM in all patients. High signal was detected within the inner ear for 1 week or more (mean: 10 days; range: 7–16 days). Changes in morphology and latency of CAPs were observed within 30 min of the dilatory injection into the ES in all patients. Administration of GD into the vestibule and the IT approach did not distribute the contrast in the ES and GD was observed in the perilymphatic space of the vestibule, cochlea and semicircular canals. No side effects relating to administration of GD into the ES, IT or into the vestibule were observed. To the best of our knowledge this is the first demonstration in humans that drugs injected into the endolymphatic structure of the ES diffuse to the cochlea, presumably into the ESp-SM. The possibility of injecting substances into the endolymphatic space might open up new prospects in the treatment of inner ear disorders. Further studies will be needed to define the limitations of this approach.

Cerebellar and lobar blood flow in schizophrenia: A perfusion weighted imaging study

It is still not clear whether brain hemodynamics plays a role in the functional and structural alterations in schizophrenia, since prior imaging studies showed conflicting findings. In this study we non-invasively explored cerebral and cerebellar lobe perfusion in the largest population of participants with schizophrenia thus far studied with perfusion-weighted imaging (PWI). Forty-seven participants affected by schizophrenia and 29 normal controls were recruited. PWI images were acquired following the intravenous injection of a paramagnetic contrast agent. Regional cerebral blood volume (CBV), blood flow (rCBF), and mean transit time (MTT) were obtained with the block-Circulant Singular Value Decomposition (cSVD) for frontal, temporal, parietal, occipital, and cerebellar lobes, bilaterally. Perfusion parameters were separately obtained for both gray and white matter in each lobe. Subjects with schizophrenia showed no significant differences in perfusion parameters when compared with controls. Interestingly, inverse correlations between age at onset and occipital, frontal and cerebellar MTT and between length of illness and frontal CBV were found. Preserved cerebral and cerebellar perfusion in our chronic population may in part be due to the effects of antipsychotic treatment which may have normalized blood volume and flow. Hypoperfusion in relation to chronicity, particularly in the frontal lobe, has been observed in accordance with earlier studies using positron emission tomography.

Hyaluronic acid: in vitro and in vivo analysis, biochemical properties and histological and morphological evaluation of injected filler

BACKGROUND No human model has emerged as an accepted standard to evaluate tissue filler longevity. OBJECTIVES To validate a human model adequate to compare soft tissue filler degradation and tissue reaction. MATERIALS AND METHODS We evaluated in 18 patients the persistence of hyaluronic acid (HA) filler injected into labial tissue analyzing hyaluronidase (HYAL) activity by means of in vitro and in vivo tests, MRI and histological and ultra-structural examination at 3 and 6 months postop. RESULTS MRI examination revealed the presence of HA filler in a clear hyperintense area. Histology demonstrated fibroblast activation. The amount and the degradation rate of HYAL and HA did not show a linear correlation. CONCLUSION MRI demonstrated the presence of HA in lip tissue even after 6 months. Biopsies at 3 months revealed tissue maturation and at 6 months confirmed the ability of HA to reorganize and integrate the extracellular matrix. The absence of linear correlation between HYAL and HA revealed that the result clinically is probably dependent on systemic factors which can determine HYAL activity and therefore HA longevity.

Pneumolabyrinth and positional vertigo after stapedectomy

Pneumolabyrinth due to late complications of stapes surgery is a rare entity. Symptoms may include various degrees of hearing loss, tinnitus and dizziness. We report the case of a 67-year-old patient who developed a unique pneumolabyrinth variant affecting the vestibule, cochlea and semicircular canals 28 years after stapedectomy. The patient presented with intractable paroxysmal positional vertigo of the lateral semicircular canal. The pneumolabyrinth was visualized by means of high resolution computed tomography. Exploratory tympanotomy findings were consistent with a perilymphatic fistula. One year after surgical treatment the subject was free of vertigo spells. Pathogenetic mechanisms are discussed.

Induced endolymphatic flow from the endolymphatic sac to the cochlea in Ménière's disease

OBJECTIVE The aim of the present study was to verify whether drugs injected into the endolymphatic sac (ES) can reach the cochlea and possibly treat inner ear disorders. STUDY DESIGN Prospective cohort study. SETTING Tertiary referral center, Otolaryngology Department, University of Verona. SUBJECTS AND METHODS Patients with Ménières disease (MD) who were candidates for ES decompression were selected. Nineteen subjects received dexamethasone (DEX) via injection into the ES. To objectively define whether substances administered into the ES could reach the cochlea, we added gadolinium (GD) in three patients. All subjects had intraoperative electrocorticogram recordings and an audiologic follow-up. The three subjects who underwent injection of the DEX-GD solution were followed-up with magnetic resonance imaging. The audio-logical data are presented during a follow-up period of 12 months. RESULTS Intraoperative electrocochleography recordings revealed no changes in two patients and summating potentials and compound action potential latency and wave-form modifications in all the other subjects. GD distribution was observed from 48 hours to one week after ES injection into the cochlea of the three subjects injected with DEX-GD. GD-related enhancement of inner ear structures lasted more than two weeks in all subjects. Pure tone average results showed hearing improvement of at least 20 dB HL in 42 percent of patients (8 of 19) at the 12-month follow-up. Statistically significant differences emerged between the mean pure tone average of the ES procedure subjects at one and 12 months after surgery (P = 0.0096). CONCLUSION This novel approach might reveal new prospects for treating viral, metabolic, autoimmune, and genetic disorders of the cochlea.