The Effects of Obstructive Sleep Apnea Syndrome on the Dentate Gyrus and Learning and Memory in Children.

Obstructive sleep apnea syndrome (OSAS) is associated with intermittent hypoxia and sleep loss. In children, impairments of cognitive function are important manifestations, but the underlying pathology is unknown. We hypothesized that OSAS would affect the dentate gyrus, a hippocampal subdivision essential to neurogenesis and cognition, and that this impact would further affect cognitive function in children. In children with OSAS (n = 11) and control subjects (n = 12; age and sex matched), we performed diffusion tensor imaging and structural MRI, polysomnography, and neuropsychological assessments. We found that OSAS was associated with decreased mean diffusivity of the left dentate gyrus (p = 0.002; false discovery rate corrected; adjusting for sex, age, and body mass index), showing a large effect size (partial η2 = 0.491), but not with any other structural measures across the brain. Decreased dentate gyrus mean diffusivity correlated with a higher apnea hypopnea index (Spearman's r = -0.50, p = 0.008) and a greater arousal index (r = -0.44, p = 0.017). OSAS did not significantly affect neuropsychological measures (p values >0.5); however, a lower verbal learning score correlated with lower dentate gyrus mean diffusivity (r = 0.54, p = 0.004). Path analysis demonstrated that dentate gyrus mean diffusivity mediates the impact of OSAS on verbal learning capacity. Finally, the diagnostic accuracy of a regression model based on dentate gyrus mean diffusivity reached 85.8% (cross validated). This study demonstrates a likely pathway of effects of OSAS on neurocognitive function in children, as well as potential utility of the dentate gyrus mean diffusivity as an early marker of brain pathology in children with OSAS.SIGNIFICANCE STATEMENT In this study we investigate the relationships between dentate gyrus structure, hippocampus-dependent cognition, and obstructive sleep apnea syndrome (OSAS). We demonstrate lower mean diffusivity of the dentate gyrus in children with OSAS, which correlates with a lower verbal learning and memory score. This study provides new evidence of disrupted microstructure of the dentate gyrus in children with OSAS that may help explain some of the neurocognitive deficits described in these children.

Transoral resection of stylopharyngeus calcification: a unique manifestation of a stylohyoid complex syndrome.

BACKGROUND: Eagle syndrome is often considered in the work-up of odynophagia and neck pain. Classically, this is manifested by ossification or calcification of the stylohyoid ligament or styloid process. There are no reported cases of stylopharyngeal calcification leading to these symptoms. CASE: We describe a patient with a suspected submucosal pharyngeal foreign body who was found to have a calcified stylopharyngeus muscle and tendon during surgery. The patient experienced full resolution of symptoms after transoral robotic resection. This diagnosis was initially missed because the radiology was inconsistent with Eagle syndrome. CONCLUSION: This is the first report of isolated stylopharyngeal calcification, and this unique manifestation of a stylohyoid complex syndrome should be considered in patients with symptoms of Eagle syndrome without styloid elongation.

Novel retrospective, respiratory-gating method enables 3D, high resolution, dynamic imaging of the upper airway during tidal breathing.

PURPOSE: A retrospective, respiratory-gated technique for measuring dynamic changes in the upper airway over the respiratory cycle was developed, with the ultimate goal of constructing anatomically and functionally accurate upper airway models in obstructive sleep apnea patients. METHODS: Three-dimensional cine, retrospective respiratory-gated, gradient echo imaging was performed in six adolescents being evaluated for polycystic ovary syndrome, a disorder with a high obstructive sleep apnea prevalence. A novel retrospective gating scheme, synchronized to flow from a nasal cannula, limited image acquisition to predefined physiological ranges. Images were evaluated with respect to contrast, airway signal leakage, and demonstration of dynamic airway area changes. RESULTS: Two patients were diagnosed with obstructive sleep apnea. Motion artifacts were absent in all image sets. Scan efficiency ranged from 48 to 88%. Soft tissue-to-airway contrast-to-noise ratio varied from 6.1 to 9.6. Airway signal leakage varied between 10 and 17% of soft tissue signal. Automated segmentation allowed calculation of airway area changes over the respiratory cycle. In one severe apnea patient, the technique allowed demonstration of asynchronous airway expansion and contraction above and below a severe constriction. CONCLUSIONS: Retrospective, respiratory gated imaging of the upper airway has been demonstrated, utilizing a gating algorithm to ensure acquisition over specified ranges of respiratory rate and tidal volume.

Teeth: what radiologists should know.

Disease of the teeth and their support structures is common and frequently seen at imaging of the head and neck. Recognition of dental disease by the interpreting radiologist has the potential to alter the course of patient care, such as when periapical disease is identified as the cause of sinusitis or pericoronitis is identified as the cause of deep neck infection. Furthermore, incidental recognition of carious lesions in both children and adults who are undergoing CT for other reasons may alert the patient and care team of the need for a dental consultation. In fact, most of the images of dental and periodontal conditions that are used in this article were obtained from CT studies that were performed to investigate other problems. Familiarity with the imaging appearance of common dental conditions, such as hyperdontia and hypodontia, tooth trauma, periodontal disease, caries, periapical disease, odontogenic sinusitis, and deep neck infections, allows the radiologist to render a timely, confident, and specific diagnosis of dental abnormalities, even when such findings are unexpected.

Upper airway structure and body fat composition in obese children with obstructive sleep apnea syndrome.

RATIONALE: Mechanisms leading to obstructive sleep apnea syndrome (OSAS) in obese children are not well understood. OBJECTIVES: The aim of the study was to determine anatomical risk factors associated with OSAS in obese children as compared with obese control subjects without OSAS. METHODS: Magnetic resonance imaging was used to determine the size of upper airway structure, and body fat composition. Paired analysis was used to compare between groups. Mixed effects regression models and conditional multiple logistic regression models were used to determine whether body mass index (BMI) Z-score was an effect modifier of each anatomic characteristic as it relates to OSAS. MEASUREMENTS AND MAIN RESULTS: We studied 22 obese subjects with OSAS (12.5 ± 2.8 yr; BMI Z-score, 2.4 ± 0.4) and 22 obese control subjects (12.3 ± 2.9 yr; BMI Z-score, 2.3 ± 0.3). As compared with control subjects, subjects with OSAS had a smaller oropharynx (P < 0.05) and larger adenoid (P < 0.01), tonsils (P < 0.05), and retropharyngeal nodes (P < 0.05). The size of lymphoid tissues correlated with severity of OSAS whereas BMI Z-score did not have a modifier effect on these tissues. Subjects with OSAS demonstrated increased size of parapharyngeal fat pads (P < 0.05) and abdominal visceral fat (P < 0.05). The size of these tissues did not correlate with severity of OSAS and BMI Z-score did not have a modifier effect on these tissues. CONCLUSIONS: Upper airway lymphoid hypertrophy is significant in obese children with OSAS. The lack of correlation of lymphoid tissue size with obesity suggests that this hypertrophy is caused by other mechanisms. Although the parapharyngeal fat pads and abdominal visceral fat are larger in obese children with OSAS we could not find a direct association with severity of OSAS or with obesity.

Heterotopic gastrointestinal cyst within the submandibular space in an adult: A case report and review of the literature.

Heterotopic gastrointestinal cysts (HGIC) are rare congenital cysts that arise anywhere along the gastrointestinal tract. HGICs are infrequently reported in the oral cavity; 0.3% of HGICs are reported in the tongue and even more rarely in the submandibular space. Oral HCIGs are more common in children with only 13 reported cases in adults. In the present report, we discuss the differential diagnoses of the submandibular space lesions and describe a rare case of a very large submandibular space HGIC in an adult patient.

Malignant solitary fibrous tumor of the floor of the mouth in a 71-year-old male: A case report.

Solitary fibrous tumors are rare mesenchymal tumors originally described in the pleura that infrequently metastasize. We present a 71-year-old male complaining of hemoptysis and a mass with the characteristic appearance of a hemangioma in the floor of the mouth. The mass had nonspecific imaging features on CT and MRI. After unsuccessful fine needle aspiration, surgical excision and biopsy with histological analysis revealed a solitary fibrous tumor, high risk variant. CT Imaging and lymph node biopsy showed gross total resection and no metastatic adenopathy. Given the high risk for malignancy, the patient received adjuvant radiation without subsequent clinical or imaging signs of recurrence. This case report demonstrates the presentation of this rare entity that can often be confused with other tumors in this region, given its nonspecific clinical and imaging findings.

Left-sided facial mass in an adult female.

A left maxillary sinus soft tissue mass was discovered on computed tomography in a 70-year-old woman who had been experiencing blood-tinged mucus for 2 years. The lesion demonstrated mild enhancement, and bony destruction. Magnetic resonance imaging displayed a cerebriform appearance of the mass, which mimicked the appearance of inverted papilloma. However, histology and staining identified the lesion as ameloblastoma. Resection of the tumor was successful with no recurrence 1 month later on follow-up computed tomography. This case represents an unusual imaging presentation of ameloblastoma, and an opportunity to avoid the misdiagnosis of inverted papilloma in similar future cases.

Inflammatory myofibroblastic tumor of the larynx: Case report.

Inflammatory myofibroblastic tumor is usually a benign tumor of mesenchymal origin that is rarely found in the larynx. This case explores the unique laryngeal location and presentation of this tumor as well as the challenging radiographic and histologic findings.

Bridging bronchus (pseudocarina) and left pulmonary artery sling: A case report and literature review.

Congenital airway malformations can present with respiratory distress, cyanosis, and difficulty feeding in the neonate or infant. Clinical presentation may vary from asymptomatic to fatal airway obstruction. They may exist in isolation or in association with vascular rings and slings, bronchopulmonary malformations, and/or syndromes. We present an unusual case of bridging bronchus, complete bronchial rings, and left pulmonary artery sling presenting with recurrent croup, highlighting the importance of bronchoscopy and CT imaging to achieve an accurate diagnosis in patients with recurrent croup and/or respiratory failure not responding to usual treatment measures and a multidisciplinary treatment approach.

Diffusion-tensor imaging implicates prefrontal axonal injury in executive function impairment following very mild traumatic brain injury.

PURPOSE: To determine whether frontal white matter diffusion abnormalities can help predict acute executive function impairment after mild traumatic brain injury (mTBI). MATERIALS AND METHODS: This study had institutional review board approval, included written informed consent, and complied with HIPAA. Diffusion-tensor imaging and standardized neuropsychologic assessments were performed in 20 patients with mTBI within 2 weeks of injury and 20 matched control subjects. Fractional anisotropy (FA) and mean diffusivity (MD) images (imaging parameters: 3.0 T, 25 directions, b = 1000 sec/mm(2)) were compared by using whole-brain voxelwise analysis. Spearman correlation analyses were performed to evaluate associations between diffusion measures and executive function. RESULTS: Multiple clusters of lower frontal white matter FA, including the dorsolateral prefrontal cortex (DLPFC), were present in patients (P < .005), with several clusters also demonstrating higher MD (P < .005). Patients performed worse on tests of executive function. Lower DLPFC FA was significantly correlated with worse executive function performance in patients (P < .05). CONCLUSION: Impaired executive function following mTBI is associated with axonal injury involving the DLPFC.

Diffusion tensor imaging abnormalities in patients with mild traumatic brain injury and neurocognitive impairment.

OBJECTIVE: To determine if diffusion tensor imaging can differentiate patients with chronic cognitive impairment after mild traumatic brain injury (TBI) from normal controls. METHODS: Ten patients with persistent cognitive impairment after mild TBI were evaluated at least 2 years after injury. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were measured at white matter regions susceptible to axonal injury after TBI. Comparison was made to 10 normal controls. RESULTS: Fractional anisotropy was significantly lower (4.5%; P = 0.01) and ADC higher (7.1%; P = 0.04) in patients at the left side of the genu of the corpus callosum. The mild TBI group also demonstrated a significant increase in FA within the posterior limb of the internal capsule bilaterally (left, 5.1%; P = 0.03; right, 1.9%; P = 0.04). CONCLUSIONS: These results demonstrate low FA and high ADC in the genu of the corpus callosum of mild TBI patients with persistent cognitive impairment, suggesting that permanent white matter ultrastructural damage occurs in mild TBI, and that such damage may be associated with persistent cognitive disability. Further longitudinal studies are warranted to elucidate the full importance of the findings.

Association Between Periodic Limb Movements in Sleep and Cerebrovascular Changes in Children With Sickle Cell Disease.

STUDY OBJECTIVES: Periodic limb movements (PLMs) have been associated with increased risk of stroke, but there is currently scarce research exploring this relationship in the setting of sickle cell disease (SCD). The aim of this study was to explore whether increased PLMs in children with SCD are associated with increased risk of cerebrovascular disease and to determine if there are any clinical or laboratory differences between children with SCD with elevated periodic limb movement index (PLMI) versus those with normal PLMI. METHODS: This study is a comprehensive review of medical records of 129 children with SCD (aged ≤ 18 years) who had undergone polysomnography for evaluation of sleep-disordered breathing. RESULTS: Elevated PLMI (PLMI > 5 events/h) was present in 42% (54/129) of children with SCD. Children with elevated PLMI were found to have higher percentage of hemoglobin S, lower total iron, higher arousal index and tendency toward elevated transcranial Doppler velocity (P = .063, odds ratio = 3.9, 95% CI 0.93-16.22). While association between elevated PLMI and isolated cerebrovascular stenosis (P = .050, odds ratio 5.6, 95% CI 1.0-31.10) trended toward significance, there was significantly greater proportion of children with elevated PLMI who had cerebrovascular stenosis with Moyamoya disease (P = .046) as demonstrated by magnetic resonance imaging (MRI). CONCLUSIONS: The prevalence of elevated PLMI in children with SCD was higher than in previously published data. Elevated PLMI was significantly associated with greater rates of cerebrovascular disease as detected by MRI.

Association between pretreatment obesity, sarcopenia, and survival in patients with head and neck cancer.

BACKGROUND: Body mass index (BMI), sarcopenia, and obesity-related comorbidities have been associated with head and neck squamous cell carcinoma (HNSCC) progression. METHODS: We conducted a retrospective analysis of 441 normal-weight, overweight, and obese HNSCC patients treated at Montefiore Medical Center (New York). Patients were grouped by BMI prior to treatment and assessed for differences in survival adjusting for comorbid conditions (cardiovascular disease and diabetes). Evidence of sarcopenia was also assessed using pretreatment abdominal CT scans in a subset of 113 patients. RESULTS: Prior to treatment, 55% of HNSCC patients were overweight or obese. Overweight/obese patients had significantly better overall survival (hazard ratio [HR] = 0.4, 95% CI: 0.3-0.6) compared to normal-weight patients, independent of comorbid conditions. Patients with sarcopenia had significantly poorer survival (HR = 2.1, 95% CI: 1.1-3.9) compared to non-sarcopenic patients, with the strongest association seen among overweight/obese patients. CONCLUSION: Our data support the importance of sarcopenia assessment, in addition to BMI, among patients with HNSCC.

Multifocal white matter ultrastructural abnormalities in mild traumatic brain injury with cognitive disability: a voxel-wise analysis of diffusion tensor imaging.

The purpose of the present study is to identify otherwise occult white matter abnormalities in patients suffering persistent cognitive impairment due to mild traumatic brain injury (TBI). The study had Institutional Review Board (IRB) approval, included informed consent and complied with the U.S. Health Insurance Portability and Accountability Act (HIPAA) of 1996. We retrospectively analyzed diffusion tensor MRI (DTI) of 17 patients (nine women, eight men; age range 26-70 years) who had cognitive impairment due to mild TBI that occurred 8 months to 3 years prior to imaging. Comparison was made to 10 healthy controls. Fractional anisotropy (FA) and mean diffusivity (MD) images derived from DTI (1.5 T; 25 directions; b = 1000) were compared using whole brain histogram and voxel-wise analyses. Histograms of white matter FA show an overall shift toward lower FA in patients. Areas of significantly decreased FA (p < 0.005) were found in the subject group in corpus callosum, subcortical white matter, and internal capsules bilaterally. Co-located elevation of mean diffusivity (MD) was found in the patients within each region. Similar, though less extensive, findings were demonstrated in each individual patient. Multiple foci of low white matter FA and high MD are present in cognitively impaired mild TBI patients, with a distribution that conforms to that of diffuse axonal injury. Evaluation of single subjects also reveals foci of low FA, suggesting that DTI may ultimately be useful for clinical evaluation of individual patients.

Vertebral augmentation with a flexible curved needle: preliminary results in 17 consecutive patients.

This report details a trial demonstrating the viability of a blunt-tipped curved needle for use as a cement injection device for vertebral body augmentation. Between January and September 2007, 17 consecutive patients (eight men and nine women; average age, 76 years; age range, 52-97 years) underwent vertebral body augmentation with a blunt-tipped curved nitinol injection needle via a single pedicle to treat pain due to acute vertebral body compression fractures. All patients were successfully treated without complication. The results of the trial demonstrate that a curved blunt-tipped nitinol needle is a viable alternative to a rigid injection cannula when performing vertebral body augmentation with cement.

Brain injury due to ventricular shunt placement delineated by diffusion tensor imaging (DTI) tractography.

OBJECTIVE: Infection and hemorrhage are well-known complications from insertion of intracranial shunts. However, permanent injury to the brain caused by catheterization of the cerebral ventricles has rarely been reported. METHODS: We report a patient who presented at age 14 years for evaluation of a severe behavioral disorder. The patient had sustained direct injury to the corticospinal tract and limbic system during revision of a ventriculoperitoneal shunt at the age of 9 years. RESULTS: Despite persistent evidence of severe disruption of the corticospinal tract on diffusion tensor imaging at age 14 years, the patient had regained complete motor function. CONCLUSION: Recovery of motor function after serious injury to motor cortex during childhood is a dramatic example of the plasticity of the child's brain to injury. In addition, we suggest that the behavioral disorder that emerged in this patient may be related to limbic system injury suffered during the shunt revision.

Preoperative 18F-FDG-PET/CT vs Contrast-Enhanced CT to Identify Regional Nodal Metastasis among Patients with Head and Neck Squamous Cell Carcinoma.

Objective Our objective was to compare the accuracy of preoperative positron emission tomography (PET)/computed tomography (CT) and contrast-enhanced CT (CECT) in detecting cervical nodal metastases in patients treated with neck dissection and to scrutinize the ability of each modality to determine nodal stage. Study Design Case series with chart review. Setting Montefiore Medical Center, Bronx, New York. Subjects and Methods Patients who underwent neck dissection at our institution for primary treatment of head and neck squamous cell carcinoma (HNSCC) and had received preoperative PET/CT and CECT were included in this study. Imaging studies were reinterpreted by 3 specialists within the field and compared for interreader agreement. Concordance between radiology and histopathology was measured using neck levels and sides, along with patient nodal stage. Sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and agreement coefficients were calculated. Results Seventy-three patients were included in the study. Sensitivity was 0.69 and 0.94 (level and side) for PET/CT vs 0.53 and 0.66 for CECT ( P = .056, P = .001). Specificity was 0.86 and 0.56 for PET/CT vs 0.91 and 0.76 for CECT ( P = .014, P = .024). No significant difference was found in overall accuracy ( P = .33, P = .88). The overall agreement percentages between N stage called by imaging modality and pathology were 52% and 55% for PET/CT and CECT, respectively. Conclusion No significant difference in sensitivity was found between PET/CT and CECT. CECT was found to have superior specificity compared with PET/CT. The information gleaned from each modality in the pretreatment evaluation of HNSCC appears to be complementary.

Chorea-acanthocytosis: a mimicker of Huntington disease case report and review of the literature.

BACKGROUND: Neuroacanthocytosis consists of a group of rare heterogeneous neurodegenerative disorders associated with acanthocytosis. Chorea-acanthocytosis, a variety of neuroacanthocytosis, is an autosomal recessive condition with clinical and radiologic features similar to Huntington disease. Although difficult, distinguishing between these entities is crucial as the implications for genetic counseling are significant. REVIEW SUMMARY: We report the case of a 33-year-old female who presented to our institution with a 3-year history of chorea. The patient's prominent orofacial symptoms and the presence of acanthocytes on peripheral blood smear led to the correct diagnosis of chorea-acanthocytosis. CONCLUSIONS: The significant similarities between chorea-acanthocytosis and Huntington disease at the clinical and radiologic levels can lead to an initial misdiagnosis. Clinical clues suggestive of chorea-acanthocytosis include prominent orofacial dyskinesias, often causing dysarthria and dysphagia. Acanthocytosis, when present on peripheral blood smear, can confirm the diagnosis.