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We demonstrate efficient transverse compression of a 12.5 MeV/c muon beam stopped in a helium gas target featuring a vertical density gradient and crossed electric and magnetic fields. The muon stop distribution extending vertically over 14 mm was reduced to a 0.25 mm size (rms) within 3.5 µs. The simulation including cross sections for low-energy µ^{+}-He elastic and charge exchange (µ^{+}â muonium) collisions describes the measurements well. By combining the transverse compression stage with a previously demonstrated longitudinal compression stage, we can improve the phase space density of a µ^{+} beam by a factor of 10^{10} with 10^{-3} efficiency.
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PURPOSE: The purpose of this study was to describe the role of explorative tympanotomy in patients with Profound Sudden Sensorineural Hearing Loss (SSNHL) without clinical evidence of perilymphatic or labyrinthine fistula and to compare intraoperative findings with the postoperative hearing outcome. STUDY DESIGN: Retrospective study of all patients diagnosed with SSNHL who underwent explorative tympanotomy between 2002 and 2005. SETTINGS: Tertiary care university-affiliated hospital. SUBJECTS AND METHODS: Eighty-two patients were diagnosed with unilateral profound SSNHL and underwent tympanotomy with sealing of the round and oval windows. Values of pure tone audiograms and percentage hearing loss of patients with and without intraoperative diagnosed perilymphatic fistula (PLF) were compared and analyzed. RESULTS: PLF was diagnosed in 28% cases intraoperatively. In most cases, hearing improved significantly after surgery. Interestingly, patients with PLF had a 2.4 times greater decrease of percentage hearing loss compared to patients without PLF. CONCLUSIONS: Explorative tympanotomy seems to be useful in patients with profound SSNHL. Patients with PLF benefit more from the surgical procedure and have better outcome than patients without PLF.
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Fístula/cirurgia , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Súbita/diagnóstico , Ventilação da Orelha Média/métodos , Janela da Cóclea/cirurgia , Doenças Vestibulares/cirurgia , Adulto , Audiometria de Tons Puros , Aqueduto da Cóclea/fisiopatologia , Aqueduto da Cóclea/cirurgia , Feminino , Fístula/diagnóstico , Seguimentos , Perda Auditiva Neurossensorial/cirurgia , Perda Auditiva Súbita/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Resultado do Tratamento , Doenças Vestibulares/diagnósticoRESUMO
OBJECTIVES: Pus of peritonsillar abscess (PTA) contains very high amylase levels in some patients. The objective of this study was to further test this finding and to check whether high amylase levels in peritonsillar abscess originate from contamination by saliva during aspiration. STUDY DESIGN: Prospective study. SETTING: Tertiary care university hospital. PARTICIPANTS: The study includes 64 patients with PTA, 8 patients with a neck abscess and 12 patients with a dental abscess. MAIN OUTCOME MEASURE: Amylase levels of pus and serum were compared between the groups. Clinical data regarding hospitalisation length, recurrence rate and previous antibiotic treatment were also collected. RESULTS: Mean amylase levels in the pus of the PTA group were 3045 U/L (median 59 U/L), 13 U/L in the neck abscess group (P = 0.001) and 22 U/L in the dental abscess group (P = 0.001). Mean serum amylase was higher in the PTA group; PTA - 50 U/L, neck abscess - 37 U/L (P = 0.002) and dental abscess - 26 U/L (P < 0.002). All of the patients with amylase levels above 65 U/L had a first episode of PTA. In contrast, 40% of patients with amylase lower than 65 U/L had recurrent PTA (P = 0.003). CONCLUSION: A clear association is seen between minor salivary glands and peritonsillar abscess. The high amylase level in peritonsillar pus is not from contamination with saliva.
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Abscesso/enzimologia , Amilases/análise , Abscesso Peritonsilar/enzimologia , Adulto , Amilases/sangue , Antibacterianos/uso terapêutico , Feminino , Humanos , Tempo de Internação , Masculino , Pescoço , Recidiva , Estudos Retrospectivos , Supuração/enzimologiaRESUMO
In a recent call to action, we described pressing issues in the health-service-psychology (HSP) internship from the perspective of interns. In our article, we sought to initiate a dialogue that would include trainees and bring about concrete changes. The commentaries on our article are a testament to the readiness of the field to engage in such a dialogue, and we applaud the actionable recommendations that they make. In our response to these commentaries, we seek to move the conversation further forward. We observe two themes that cut across these responses: the impetus to gather novel data on training (the "need to know") and the importance of taking action (the "need to act"). We emphasize that in new efforts to gather data and take policy-level action, the inclusion of trainee stakeholders (as well as others involved in and affected by HSP training) is a crucial ingredient for sustainable and equitable change.
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A major technological challenge in building a muon cooling channel is operating rf cavities in multitesla external magnetic fields. We report the first proof-of-principle experiment of a high pressure gas-filled rf cavity for use with intense ionizing beams and strong external magnetic fields. rf power consumption by beam-induced plasma is investigated with hydrogen and deuterium gases with pressures between 20 and 100 atm and peak rf gradients between 5 and 50 MV/m. The low pressure case agrees well with an analytical model based on electron and ion mobilities. Varying concentrations of oxygen gas are investigated to remove free electrons from the cavity and reduce the rf power consumption. Measurements of the electron attachment time to oxygen and rate of ion-ion recombination are also made. Additionally, we demonstrate the operation of the gas-filled rf cavity in a solenoidal field of up to 3 T, finding no major magnetic field dependence. All these results indicate that a high pressure gas-filled cavity is a viable technology for muon ionization cooling.
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The challenges observed in health service psychology (HSP) training during COVID-19 revealed systemic and philosophical issues that preexisted the pandemic, but became more visible during the global health crisis. In a position paper written by 23 trainees across different sites and training specializations, the authors use lessons learned from COVID-19 as a touchstone for a call to action in HSP training. Historically, trainee voices have been conspicuously absent from literature about clinical training. We describe longstanding dilemmas in HSP training that were exacerbated by the pandemic and will continue to require resolution after the pandemic has subsided. The authors make recommendations for systems-level changes that would advance equity and sustainability in HSP training. This article advances the conversation about HSP training by including the perspective of trainees as essential stakeholders.
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Atum/fisiologia , Animais , Oceano Atlântico , Demografia , Pesqueiros , Especificidade da EspécieRESUMO
Traditionally, imaging of renal infections was largely through a multimodality approach. Excretory urography, ultrasonography, nuclear scintigraphy, and CT all played major roles; however, in recent years, CT has increased in prominence in the imaging and evaluation of renal infection. Part of the reason for this trend includes improvements in the availability of CT scanners and more timely access to them. Helical scanning technology has also greatly increased the quality and usefulness of the information CT provides. Most uncomplicated cases of acute renal infection in adults do not require imaging for diagnosis and treatment. When imaging is indicated, however, contrast-enhanced CT almost always is the study of choice. For cases in which renal calculi may be present, the study should also include noncontrast images through the kidneys.
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Diagnóstico por Imagem/métodos , Nefropatias/diagnóstico , Nefropatias/microbiologia , Infecções Urinárias/diagnóstico , Abscesso/diagnóstico , Adulto , Humanos , Imageamento por Ressonância Magnética/métodos , Pielonefrite/diagnóstico , Pielonefrite Xantogranulomatosa/diagnóstico , Cintilografia/métodos , Tomografia Computadorizada por Raios X/métodos , Tuberculose/diagnóstico , Ultrassonografia/métodos , Infecções Urinárias/microbiologiaRESUMO
New techniques in quantitative imaging are needed to accelerate understanding of brain development and function in children. In this study we evaluate the reliability and validity of an automated parcellation method for the measurement of large and small brain regions in normal and developmentally disabled children. We utilized an adaptation of the Talairach atlas to semi-automatically quantify brain volumes from 10 children with fragile X syndrome, 10 age- and gender-matched controls and 10 adult controls comparing them to 'gold standard' manually delineated regions. Excellent sensitivity, specificity, intra-class correlation and positive predictive value were achieved for large structures although results were less satisfactory for smaller structures, illustrating the limits of resolution of the method. Statistically significant differences in regional brain volumes were shown between males and females, children and adults, and individuals with fragile X and matched controls. This study demonstrates an automated method which rapidly and accurately quantifies large neuroanatomical structures, but not smaller structures. This method is sufficiently accurate to demonstrate some known anatomical differences in individuals with fragile X; the results suggest that this method could be applied to the assessment of brain volume in other neurodevelopmental disabilities.
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Encéfalo/anormalidades , Processamento Eletrônico de Dados/métodos , Processamento Eletrônico de Dados/estatística & dados numéricos , Adulto , Fatores Etários , Análise de Variância , Criança , Pré-Escolar , Deficiências do Desenvolvimento/etiologia , Feminino , Síndrome do Cromossomo X Frágil/complicações , Síndrome do Cromossomo X Frágil/genética , Humanos , Inteligência , Imageamento por Ressonância Magnética , Masculino , Valor Preditivo dos Testes , Fatores SexuaisRESUMO
OBJECTIVES: To assess the incremental diagnostic yield of testing vestibulo-ocular (VOR) gain with high-frequency pseudo-random rotational chair (PsRRC) over testing with bithermal electronystagmography caloric tests in the dizzy patient, particularly in detecting bilateral vestibular loss. PATIENTS AND METHODS: One hundred ninety-eight patients presenting with dizziness underwent PsRRC and caloric testing. The VOR gain on PsRRC was measured at 0.32 to 5.0 Hz, with gain categorized as normal or decreased. PsRRC results were compared with caloric responses, also categorized as normal, or into graded categories of unilateral or bilateral vestibular loss. RESULTS: Reduced PsRRC gain was found in 29 (15%) patients, and reduced caloric tests responses in 70 (35%), with 25 (13%) having bilateral loss. Of patients with reduced chair gain, 25 of 29 (86%) demonstrated bilateral caloric loss. PsRRC gain was normal in most patients with unilateral caloric weakness, but was decreased in all patients with bilateral caloric weakness. The probability of a patient with completely normal caloric responses having an abnormal rotation chair in this study group was under 1% (1 of 128). CONCLUSIONS: PsRRC testing does not offer much additional diagnostic benefit when caloric responses are normal. It is useful in specific conditions, such as unilateral caloric loss for which the patient is not compensating, borderline caloric loss when traditional water caloric tests cannot be used, or for monitoring progressive bilateral vestibular loss.
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Testes Calóricos , Dominância Cerebral , Eletronistagmografia , Doença de Meniere/diagnóstico , Reflexo Vestíbulo-Ocular , Testes de Função Vestibular , Adulto , Dominância Cerebral/fisiologia , Humanos , Doença de Meniere/fisiopatologia , Reflexo Anormal/fisiologia , Reflexo Vestíbulo-Ocular/fisiologia , Rotação , Processamento de Sinais Assistido por ComputadorRESUMO
OBJECTIVE: To determine the efficacy of intratympanic gentamicin instillation as treatment of incapacitating unilateral Meniere's disease, using a predetermined regimen with a fixed dose. STUDY DESIGN: A prospective study from a single institution between 1988 and 1998. METHODS: One hundred fourteen patients were enrolled in this study. Gentamicin (26.7 mg/mL) was administered three times daily for 4 consecutive days. The Committee on Hearing and Equilibrium Guidelines for Reporting Treatment Results in Meniere's Disease of the American Academy of Otolaryngology and Head and Neck Surgery (1985) were used. RESULTS: Comprehensive data were available for 90 individuals. Complete control of vertigo was achieved in 76 (84.4%), substantial control in 8 (9.0%), limited control in 2 (2.2%), and insignificant control in 4 (4.4%) patients. Disability scores at the end of 2 years were as follows: 76 patients (84.4%) had no disability, 5 (5.6%) had mild disability, 2 (22%) had moderate disability, and 7(7.8%) had severe disability. Caloric testing responses, as determined using electronystagmography, were as follows: 71% of the patients had an absent ice-water response, 16% had a positive ice-water response, and in 13% there continued to be present a bithermal response. Hearing was worse in 22 patients (25.6%), unchanged in 41 (48.2%), and improved in 22 (25.6%). CONCLUSIONS: Intratympanic gentamicin administration using this particular protocol is an effective treatment option for patients with disabling unilateral Meniere's disease. Hearing loss is a distinct possibility, and patients should be advised accordingly.
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Gentamicinas/administração & dosagem , Doença de Meniere/tratamento farmacológico , Adulto , Idoso , Audiometria de Tons Puros , Testes Calóricos , Feminino , Perda Auditiva/etiologia , Humanos , Instilação de Medicamentos , Masculino , Doença de Meniere/complicações , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Membrana TimpânicaRESUMO
During the last few decades antibiotics have played an extremely important role in the management of otitis media (OM). Nowadays there are only sporadic reports of its sequelae and complications in the developed countries. Nevertheless, complications of OM still arise and the potential seriousness of this problem emphasizes the need for a high degree of monitoring. We report herewith a case of acute mastoiditis in an 18-month-old infant with chronic suppurative otitis media (CSOM). Repeated cultures from the middle ear and mastoid cavity yielded Salmonella type C. The treatment modality and the pathophysiologic aspects are discussed.
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Mastoidite/etiologia , Otite Média Supurativa/complicações , Infecções por Salmonella/etiologia , Doença Aguda , Ceftriaxona/uso terapêutico , Terapia Combinada , Feminino , Humanos , Lactente , Mastoidite/fisiopatologia , Mastoidite/terapia , Otite Média Supurativa/fisiopatologia , Otite Média Supurativa/terapia , Infecções por Salmonella/fisiopatologia , Infecções por Salmonella/terapia , Tomografia Computadorizada por Raios XRESUMO
Chronic suppurative otitis media without cholesteatoma (CSOMWC) is usually associated with an increase in air conduction thresholds. However, only a few investigations reported on loss of cochlear function in the pediatric population. We undertook a prospective study in order to further delineate air and bone conduction levels in children with CSOMWC and the possible relationship between sensorineural hearing loss (SNHL) and other clinical characteristics that might reflect the extent of disease. Eighty-seven children were enrolled, 40 of which had bilateral disease. Hence, the total number of diseased ears tested was 127. Audiometric studies were performed three days after achieving a 'dry' ear following medical treatment. We found no statistically significant differences between the bone conduction threshold tested in ears with CSOMWC and control ears. This was also the case in 47 children with unilateral disease when cochlear function was investigated in the diseased and uninvolved ear in the same patient. Clinical correlation showed no association between age, sex, duration of otorrhea and presence of granulation or polyps and the degree of cochlear loss. Our study shows that CSOMWC in children has little effect on cochlear function.
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Audiometria de Tons Puros , Audição/fisiologia , Otite Média Supurativa/fisiopatologia , Adolescente , Fatores Etários , Limiar Auditivo , Condução Óssea/fisiologia , Criança , Pré-Escolar , Colesteatoma , Doença Crônica , Cóclea/fisiopatologia , Neoplasias da Orelha/patologia , Neoplasias da Orelha/fisiopatologia , Feminino , Tecido de Granulação/patologia , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Masculino , Otite Média Supurativa/tratamento farmacológico , Otite Média Supurativa/patologia , Pólipos/patologia , Pólipos/fisiopatologia , Estudos Prospectivos , Fatores Sexuais , Teste do Limiar de Recepção da FalaRESUMO
Penetrating trauma of the soft and hard palate are common in children and have been termed 'pencil point injuries.' Although such injuries are usually minor, the English literature has reported over 25 cases complicated by thrombosis of the internal carotid artery. We describe an unusual case of a 6 year old girl who presented with fever, cervical swelling and torticollis, following a pencil point injury. Physical examination and CT scan confirmed the diagnosis of internal jugular vein thrombosis (IJVT). The management of pencil point injuries and IJVT in children is reviewed and the possible mechanisms of IJVT in the case described here, are discussed.
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Veias Jugulares , Palato/lesões , Trombose/etiologia , Ferimentos Penetrantes/complicações , Criança , Feminino , Humanos , Palato/diagnóstico por imagem , Trombose/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ferimentos Penetrantes/diagnóstico por imagemRESUMO
Infections of the orbit in children usually present as a complication of sinusitis and may result in blindness or even death. Orbital cellulitis (OC) and subperiosteal abscess (SPA) represent different pathologies within the spectrum of orbital infections. The differentiation between OC and SPA is important, since it implies two different therapeutic modalities. While SPA is usually treated by incision and drainage and parenteral antibiotics, OC may be treated with antibiotics alone. Contrast enhanced CT scan is commonly used in the diagnosis of orbital infections, but does not always prove accurate in differentiating between these two conditions. MRI is superior to CT in the resolution of soft tissue pathology and may be more precise in such situations, but is less available imaging tool outside North America and Europe. There have been a few reports in the early 1980's on the use of standardized orbital ultrasound (SOU) in these two conditions. We have used SOU in seven children with sinus induced orbital infections--four with SPA and three with OC. We reviewed our experience in these patients and compared the imaging characteristics of OC and SPA on SOU with those of conventional imaging modalities, used in orbital infections. In four of the cases, CT scan was inconclusive, while SUO was diagnostic. In this preliminary report, we conclude that SOU may be useful in the diagnosis of orbital infections.
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Abscesso/diagnóstico por imagem , Doenças Orbitárias/diagnóstico por imagem , Sinusite/complicações , Abscesso/complicações , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Doenças Orbitárias/etiologia , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
INTRODUCTION: The clinical picture of lateral sinus thrombosis (LST) has changed with the advent of antibiotics, as have the utility of various diagnostic tests. LST may appear in children as a complication of acute otitis media, but nowadays it is more frequently encountered in adults with long-standing chronic ear disease. METHOD: A retrospective study of all the pediatric patients with LST between 1982 and 1997. RESULTS: Thirteen cases of LST were diagnosed and treated by our department. In six cases, LST was due to acute otitis media and in the remaining cases it was due to chronic otitis media. Headache, fever, aural discharge and mastoid tenderness were the most frequent findings in these patients and four patients were initially diagnosed with meningitis. In the majority of the patients, LST was accompanied with other intracranial complications, such as perisinus abscess, brain abscess and meningitis. One patient with multiple brain abscesses, unresponsive to several drainage procedures, died. The other patients recovered and have since been followed-up as out-patients. CONCLUSION: LST may be difficult to diagnose due to previous antibiotic treatment and to the overlap of clinical findings with other entities such as meningitis. Despite the value of modern imaging techniques in the investigation of the disease, a high index of suspicion based on the clinical picture is warranted. Our results are consistent with those of other recent studies, who found that mortality of LST has dropped below 10%.
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Trombose do Seio Lateral/etiologia , Otite Média com Derrame/complicações , Doença Aguda , Adolescente , Antibacterianos/uso terapêutico , Abscesso Encefálico/complicações , Abscesso Encefálico/tratamento farmacológico , Abscesso Encefálico/microbiologia , Cerebelo/microbiologia , Criança , Pré-Escolar , Doença Crônica , Terapia Combinada , Diagnóstico Diferencial , Feminino , Seguimentos , Infecções por Haemophilus/complicações , Infecções por Haemophilus/tratamento farmacológico , Humanos , Lactente , Trombose do Seio Lateral/complicações , Trombose do Seio Lateral/diagnóstico por imagem , Trombose do Seio Lateral/terapia , Masculino , Meningites Bacterianas/complicações , Meningites Bacterianas/tratamento farmacológico , Meningites Bacterianas/microbiologia , Otite Média com Derrame/terapia , Complicações Pós-Operatórias , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/tratamento farmacológico , Estudos Retrospectivos , Índice de Gravidade de Doença , Sucção , Tomografia Computadorizada por Raios XRESUMO
Pathological lesions confined to the internal auditory canal (IAC) commonly present with cochleovestibular symptoms; sensorineural hearing loss, tinnitus and balance disturbance. The commonest lesion of the IAC is vestibular schwannoma. Other lesions include meningioma, facial neuroma, cavernous haemangioma, lipoma and arachnoid cyst. Presentation with facial palsy and an intracanalicular lesion is suggestive of pathology other than acoustic neuroma. Magnetic resonance imaging (MRI) cannot reliably distinguish intracanalicular vestibular schwannomas from meningiomas. Particular care is required for surgery of these lesions: the facial nerve typically does not lie in a protected anterior position within the IAC.
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Meato Acústico Externo , Paralisia Facial/etiologia , Neoplasias Meníngeas/complicações , Meningioma/complicações , Adulto , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Imageamento por Ressonância Magnética/métodos , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnósticoRESUMO
Fungal involvement of the paranasal sinuses is frequently observed in the immunocompromised host, and it can become life-threatening if it is not diagnosed. Although the definitive diagnosis is made by tissue biopsy and culture, imaging is of vital importance in the clinical workup and in planning treatment. We present a case of fulminant ethmoidal sinusitis caused by Aspergillus flavus with orbital involvement in an immunocompromised patient. Standard computed tomography of the paranasal sinuses was complemented by the use of standardized orbital ultrasonography, which was able to identify the intraorbital extension. We discuss the role of standardized orbital ultrasonography as a complementary imaging modality in the diagnosis of fungal sinusitis and in the assessment of local extension. To the best of our knowledge, the role of SOU in diagnosing an orbital extension of a fungal infection of the paranasal sinuses has not been previously discussed in the literature.
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Sinusite Etmoidal/microbiologia , Infecções Oculares Fúngicas/diagnóstico por imagem , Infecções Oculares Fúngicas/microbiologia , Órbita/diagnóstico por imagem , Órbita/microbiologia , Idoso , Humanos , Masculino , UltrassonografiaRESUMO
Cystic fibrosis (CF) is the most common lethal inherited disease in the white population. It is characterized by exocrine gland epithelia dysfunction, which leads to pulmonary and pancreatic insufficiency. Since the cloning of the CF gene in 1989 and the identification of the most common CF mutation (delta F508), more than 400 different mutations have been described. These mutations appear to contribute to the heterogeneity of the CF phenotype and several reports have speculated on the relationship between the most common CF mutations and the patient's clinical status. We report the case of a 21-year-old woman with longstanding chronic pansinusitis, nasal polyposis, chronic cough and severe nasal crusting. During a period of five years she had been followed by her otolaryngologist and pediatric pulmonologist. Sweat tests performed at the age of 17 and 18 were within normal limits and she underwent repeated conventional sinonasal procedures, with no improvement in her clinical status. On her present admission, sweat tests showed a 70 meq/l chloride concentration. The diagnosis of CF was then confirmed by DNA analysis and the patient was found to carry the 3849 + 10 kB C-->T mutation. The early detection of this newly recognized form of CF in adults as well as in children presenting with sinonasal symptoms is critical for life expectancy and quality.