Evaluation of the Performance of OTOPLAN-Based Cochlear Implant Electrode Array Selection: A Retrospective Study.

Otoplan is a surgical planning software designed to assist with cochlear implant surgery. One of its outputs is a recommendation of electrode array type based on imaging parameters. In this retrospective study, we evaluated the differences in auditory outcomes between patients who were implanted with arrays corresponding to those recommended by the Otoplan software versus those in which the array selection differed from the Otoplan recommendation. Pre-operative CT images from 114 patients were imported into the software, and array recommendations were generated. These were compared to the arrays which had actually been implanted during surgery, both in terms of array type and length. As recommended, 47% of patients received the same array, 34% received a shorter array, and 18% received a longer array. For reasons relating to structure and hearing preservation, 83% received the more flexible arrays. Those who received stiffer arrays had cochlear malformations or ossification. A negative, although non-statistically significant correlation was observed between the CNC scores at 12 months and the absolute value of the difference between recommended array and implanted array. In conclusion, clinicians may be slightly biased toward shorter electrode arrays due to their perceived greater ability to achieve full insertion. Using 3D imaging during the pre-operative planning may improve clinicians' confidence to implant longer electrode arrays, where appropriate, to achieve optimum hearing outcomes.

Lessons learnt from the global iodinated contrast media shortage in head and neck imaging.

A recent shortage in the global supply of iodinated contrast media (ICM) has required health service providers to review their contrast administration policies and implement strategies to conserve inventory. This article will review the current best practices in head and neck imaging for a variety of common presentations and provide examples where alternative imaging can be considered due to the recent ICM shortage. Ultrasound and MRI techniques can feature heavily in many diagnostic processes in head and neck pathology, and a variety of common presentations can be appropriately investigated through clinical evaluation or naso-endoscopy. In many instances, for the routine assessment of non-acute adult and paediatric head and neck presentations, the use of contrast-enhanced CT can be safely minimised to conserve ICM if required.

Meniscal "Ramp" Lesions: Surgical Incidence and the Development of Magnetic Resonance Imaging Diagnostic Criteria.

PURPOSE: To establish the magnetic resonance imaging (MRI) and operative incidence of ramp lesions in a consecutive group of patients who had undergone anterior cruciate ligament reconstruction (ACLR) and to propose a graded radiologic classification that seeks to define key preoperative features that most strongly correlate with arthroscopically confirmed ramp lesions. METHODS: After retrospective review, all consecutive patients who underwent ACLR with preoperative MRI over a 16-month period were included in the study. Diagnostic arthroscopy with direct visualization of the posteromedial compartment was used to establish the true incidence of ramp lesions. Three radiologists, blinded to the surgical findings, independently analyzed the MRI scans of all patients and classified the signal intensity at the posterior meniscocapsular junction using 4 criteria (type 1, diffuse increased signal equal to adjacent femoral cartilage; type 2, diffuse increased signal greater than cartilage; type 3, diffuse increased signal plus full-height linear fluid-signal cleft; and type 4, full-height fluid-signal meniscocapsular separation). Interobserver reliability, in addition to sensitivity, specificity, and positive and negative predictive values, was calculated. RESULTS: Of the 93 patients included (mean age, 26.7 years), 11 (11.8%) were confirmed to have ramp lesions on arthroscopy. Inter-rater reliability for the MRI diagnosis of the positive ramp lesions was good, at 0.75. Type 3 criteria were the most accurate, producing average sensitivity and specificity values of 85% and 82%, respectively. CONCLUSIONS: Ramp lesions are not infrequently encountered in ACLR and, if not recognized at the time of surgery, may contribute to inferior outcomes. MRI is an effective method of preoperative assessment, and the presence of type 3 changes should be used as criteria for radiologically definitive ramp lesion diagnosis. CLINICAL RELEVANCE: This study highlights the incidence of meniscal ramp lesions encountered in ACLR surgery and the effectiveness of MRI as a preoperative imaging modality.

Adult obstructive sleep apnoea: Pathogenesis, importance, diagnosis and imaging.

Obstructive sleep apnoea (OSA) is a serious worldwide health problem. Moderate-to-severe OSA has been found in up to 50% of men and 25% of women in the middle-aged population. It results in a fourfold increase in all causes of mortality. The prevalence of OSA is underestimated, partly due to absence of symptoms but also lack of knowledge amongst the population at large as well as sectors of the medical profession. Imaging, performed predominantly by clinicians and research scientists, has been integral to evaluating the anatomical basis of OSA. Increased nasal resistance and a narrowed and elongated oropharynx lead to increased collapsibility of the upper airway, predisposing to airway collapse and apnoea during sleep when there is reduction in tone of the pharyngeal dilator muscles. Unfortunately, a significantly narrowed upper airway is usually ignored by radiologists: it is not part of their reporting 'check-list'. The imaging findings in the upper airway that are strongly associated with OSA and its sequelae in various organ systems are discussed. Imaging can strongly suggest OSA; the diagnosis requires a polysomnogram for confirmation. Treatment of moderate-to-severe disease is primarily with positive airway pressure applied by a nasal or oral mask which splints the upper airway. Although highly effective, compliance is limited and other treatment modalities are increasingly being utilized.

Imaging of adult obstructive sleep apnoea.

Obstructive sleep apnoea (OSA) is characterised by recurrent upper airway collapse during sleep resulting in chronic and repetitive hypoxia, hypercapnia, subsequent arousal and fragmented sleep. Symptoms are insidious and diagnosis is usually delayed. Moderate to severe OSA has serious health implications with significant increase in all causes of mortality in patients with the condition as compared with unaffected individuals. The prevalence of OSA in the 30-70 year age group is estimated at 27% of males and 11% of females and it increases with age. 80% of affected individuals are obese and as obesity rates rise, so has the prevalence of OSA. An overnight polysomnogram (PSG) is required for a definitive diagnosis of OSA. Imaging has played a fundamental role in the evaluation of the anatomical factors associated with recurrent upper airway collapse and the pathogenesis of OSA. The upper airway is frequently imaged by radiologists, providing an opportunity to detect features that are strongly associated with unsuspected OSA and to raise the possibility of this diagnosis. The gold standard of treatment is continuous positive airway pressure (CPAP) which acts as a pneumatic splint for the upper airway. However, efficacy is frequently limited by poor tolerance; clinicians and patients are increasingly opting for one of a range of surgical procedures. Dedicated imaging protocols can be performed for evaluation of the upper airway to aid surgical planning.

Atrophy of anterior digastric muscle detected during ultrasound of the neck--a prospective clinical study.

Anatomical variants that affect both the anterior and posterior digastric muscles are well described, and include duplications and variable origin or sites of insertion. Although agenesis or atrophy of the anterior digastric occurs in up to 40% of patients with hemifacial microsomia, to our knowledge, it has been reported only rarely in those without this syndrome. To minimise observer bias and to establish the incidence of anomalies and atrophy of this muscle, a prospective 6-year study was conducted by an experienced consultant radiologist in all patients referred for ultrasound of the head and neck. Unilateral atrophy or absence of the anterior digastric muscle was seen in 3 of 1484 patients (0.2%). All 3 were female, and they had no symptoms or clinical signs related to the finding. One subsequently had a magnetic resonance scan. Non-syndromic absence or atrophy of the anterior digastric muscle is rare, and seems to be a unilateral phenomenon. Recognition of this variant could be important before operations in which it may be used as a landmark, or during procedures in which it is used, for example, for reanimation of a static lip or during reconstruction with a submental island flap.

Can contrast-enhanced ultrasound distinguish malignant from reactive lymph nodes in patients with head and neck cancers?

The purpose of this study was to investigate the utility of contrast-enhanced ultrasound in differentiating benign from malignant cervical lymph nodes in patients with squamous cell carcinoma of the head and neck. A consecutive series of 17 patients with known head and neck malignancy scheduled for neck surgery and lymph node clearance were recruited for contrast-enhanced ultrasound evaluation. Sonographic signal intensity as a function of time, comparing features of time to peak, time to arrival and time to wash-out, was quantified. The selected node was removed surgically and submitted for histology. Contrast-enhanced ultrasound examination had 100% sensitivity and 85.7% specificity for lymph node involvement. Functional analysis revealed contrast peaks significantly earlier in the malignant nodes (mean ± standard deviation) of 24.14 ± 2.7 s compared with 29.33 ± 3.4 s (p = 0.0128). Contrast-enhanced ultrasound holds promise in the detection and characterization of metastatic nodes that would not be diagnosed as abnormal on the basis of conventional ultrasound criteria.

Bilateral visual loss: more than meets the eye.

A 72-year-old woman presented with acute onset bilateral visual loss. She had no other symptoms or signs, but had a complex past medical history including blood transfusions and immunosuppression. T2-weighted magnetic resonance imaging demonstrated bilateral occipital lobe vasogenic edema, consistent with posterior reversible encephalopathy syndrome (PRES). Her vision improved with conservative management.

Rotation of the osseous spiral lamina from the hook region along the basal turn of the cochlea: results of a magnetic resonance image anatomical study using high-resolution DRIVE sequences.

PURPOSE: To define the rotational anatomy of the osseous spiral lamina (OSL) at the hook region and along the basal turn of the cochlea and to illustrate the potential utility of high-resolution MRI images to study inner ear ultrastructure. METHODS: Retrospective review of high-resolution temporal bone MRI images in 20 consecutive adult patients referred for imaging unrelated to hearing loss. The main outcome measure utilised images in an oblique sagittal plane to measure the rotation of the OSL relative to the vertical axis in the hook region and along the basal turn of the cochlea. RESULTS: The right OSL is noted to rotate in a clockwise direction as one proceeds anteriorly; over the same distance, the left OSL rotates in an anti-clockwise direction. The average overall rotation for all subjects as measured over a distance of 1-7 mm from the posterior margin of the round window was 25.95°. Inter-subject variability was noted. CONCLUSIONS: Prominent rotation of the OSL was noted in the hook region, this being most pronounced in the proximity to the round window. This concept may have implications for cochleostomy site selection with implant surgery. The study highlights the feasibility of high-resolution MRI to be used to systematically study variations in intra-cochlear anatomy.

An update on the use of ultrasound imaging in oral and maxillofacial surgery.

Ultrasound is a relatively inexpensive, non-invasive, and readily available technique that is well tolerated by patients. It is particularly useful in the examination of superficial structures where the use of a high frequency linear probe (7.5-12 MHz) produces high definition multi-planar images. The spatial resolution achieved is superior to other methods of cross-sectional imaging and, when combined with tissue biopsying techniques such as fine needle aspiration cytology (FNAC) or core biopsy samples, it is rendered a highly specific diagnostic tool. This article provides an overview of the use of ultrasound for common head and neck conditions, including its use in salivary gland disease, and for the assessment of cervical lymphadenopathy.

Lung morphology in the elderly: comparative CT study of subjects over 75 years old versus those under 55 years old.

PURPOSE: To describe thin-section pulmonary computed tomographic (CT) features in asymptomatic elderly individuals. MATERIALS AND METHODS: Institutional review board approval was given, and informed consent was obtained. Two study groups (older group, over 75 years of age; younger group, under 55 years) were prospectively identified from outpatient requests for CT of the abdomen or brain. Fifty-six consecutive volunteers (older group: n = 40, 18 men, 22 women; younger group: n = 16, eight men, eight women) with no known respiratory disease were included. Prone thin-section CT imaging was performed, and two observers independently scored images for the presence and extent of CT features (including reticular pattern, ground glass opacity, and thin-walled cystic air spaces). Group comparisons were made, and logistic regression analysis was used to assess relationships between CT findings and age and smoking history. RESULTS: A limited predominantly subpleural basal reticular pattern was identified in the majority (24 of 40, 60%) of individuals in the older group and was absent (zero of 16) in the younger group (P < .001). Cysts were seen in 10 (25%) of the 40 subjects in the older group but were seen in none of the subjects in the younger group (P = .02). Bronchial dilation and wall thickening were also seen significantly more frequently (P < .001) in the older group (24 [60%] and 22 [55%] of 40, respectively) than in the younger group (both one [6%] of 16). All findings were independent of pack-year smoking history with multiple logistic regression analysis. CONCLUSION: Thin-section CT findings usually associated with interstitial lung disease are frequently seen in asymptomatic elderly individuals and are absent in younger subjects. Therefore, these findings may not necessarily represent clinically relevant disease.

Evaluation of normal FDG uptake in palatine tonsil and its potential value for detecting occult head and neck cancers: a PET CT study.

OBJECTIVE: The aims of the study were to (1) evaluate the range of physiological FDG uptake in normal pharyngeal palatine tonsil, and (2) investigate the possibility of establishing a cut-off threshold to distinguish between normal pharyngeal palatine tonsil FDG uptake from occult pharyngeal palatine tonsil primary cancer. METHODS: FDG PET CT of 43 consecutive patients with a low risk of head and neck cancer were reviewed by two observers. Axial PET CT was used to identify foci of FDG uptake related to the pharyngeal palatine tonsil. The highest standardized uptake value, SUVmax, of the left and right pharyngeal palatine tonsil was calculated. Similar analysis was performed on 10 consecutive patents with histologically proven occult pharyngeal palatine tonsil primary cancer. RESULTS: The mean SUVmax of the 43 right pharyngeal palatine tonsils was 4.82 (range, 1.16-12.74) and 4.68 (range, 0.88-13.65) for the 43 left pharyngeal palatine tonsils with no statistical difference observed (P=0.4). Normal pharyngeal palatine tonsil uptake was generally symmetrical and there was a positive correlation between SUVmax from the left and right sides which was statistically significant (r=0.9, P<0.0001). In the same patient the difference in SUVmax between left and right pharyngeal palatine tonsil ranged from 0.01 to 2.66 and patients with occult pharyngeal palatine tonsil primary cancer it ranged from 0.85 to 11.08. ROC analysis showed that an 'SUVmax difference' cut-off of 0.83 would achieve a sensitivity of 100% and specificity of 81% for detecting occult pharyngeal palatine tonsil primary cancers. CONCLUSIONS: There is considerable variation of pharyngeal palatine tonsil FDG uptake in patients with no pharyngeal palatine tonsil primary cancer. However, in the same patient there is generally only a small difference in uptake between left and right sides. The absolute difference in SUVmax between left and right pharyngeal palatine tonsil is a potentially useful parameter for distinguishing between normal FDG uptake in pharyngeal palatine tonsil from occult pharyngeal palatine tonsil primary cancer.

Techniques and outcomes of laryngeal cleft repair: an update to the Great Ormond Street Hospital series.

We present an update to the Great Ormond Street Hospital series of laryngeal clefts, describing a further 35 clefts of Benjamin-Inglis types 1 through 3 treated between 1992 and 2003. Associated congenital anomalies were common. Most type 1 and smaller type 2 clefts were repaired endoscopically, whereas larger clefts were repaired through an anterior approach. Increasing use was made recently of a 3-layer repair with an interposition graft of temporalis fascia. The rates of complication, revision surgery, and death were 54%, 26%, and 6%, respectively. Most of the children are now orally fed, and 9 still have a tracheotomy.