Fluoroscopic MR of the pharynx in patients with obstructive sleep apnea

PURPOSE: The purpose of our study was to introduce an ultrafast MR imaging technique of the pharynx as a diagnostic tool for viewing the mechanism of obstruction in patients with obstructive sleep apnea. METHODS: Six healthy volunteers and 16 patients with obstructive sleep apnea were examined on a 1.5-T whole-body imager using a circular polarized head coil. Ultrafast two-dimensional fast low-angle shot sequences were obtained in midsagittal and axial projections during transnasal shallow respiration at rest, during simulation of snoring, and during performance of the Müller maneuver. All patients underwent physical examination, transnasal fiberoptic endoscopy, and polysomnography. RESULTS: Five to six images were obtained per second with an in-plane resolution of 2.67 x 1.8 mm and 2.68 x 2.34 mm, allowing visualization of motion of the tongue, soft palate, uvula, and posterior pharyngeal surface. MR findings correlated well with results of clinical examination. The length of obstruction in the oropharynx, which cannot be ascertained by transnasal endoscopy of the pharynx, was clearly visible MR images. Differences between patients with obstructive sleep apnea and healthy subjects in terms of the degree of obstruction in the velopharynx and oropharynx depicted on MR images during the Müller maneuver were highly significant. CONCLUSION: We believe that ultrafast MR imaging is a reliable noninvasive method for use in the evaluation of obstructive sleep apnea.     

Selective jugular node dissection in patients with squamous carcinoma of the larynx or pharynx

We reviewed our experience with 66 patients who had 85 jugular node dissections (JND) between 1984 and 1991. When JND was used as a staging procedure in 56 patients with N0 squamous carcinoma of the larynx or hypopharynx, it identified 15 of 19 patients (79%) who had occult metastases. The pattern of neck failure in six patients after JND strongly suggests that the dissection must be carried posterior to the internal jugular vein in order to achieve adequate sampling. Neck failure was a relatively minor problem in this patient population, and the indications for elective JND may be less than compelling in most patients with N0 class laryngeal or pharyngeal squamous carcinomas. Our very limited experience with JND for resection of N1 disease supports a growing consensus that limited lymphadenectomy and aggressive radiotherapy may yield comparable results in carefully selected patients with palpable metastases. Obviously, these are issues that can only be resolved by prospective, randomized studies.     

Does pulse oximetry reliably detect aspiration in dysphagic stroke patients?

BACKGROUND AND PURPOSE: The aim of the present study was to examine the value of pulse oximetry in the diagnosis of aspiration by comparing it with the gold standard, videofluoroscopy, by use of a prospective, controlled, single-blind study design. METHODS: Pulse oximetry was performed simultaneously with videofluoroscopy in 54 consecutive dysphagic stroke patients. Oxygen saturation measurements were taken before the video-fluoroscopic examination (baseline), on swallowing and continuously for 2 minutes after swallowing, and 10 minutes later. RESULTS: Pulse oximetry reliably predicted aspiration or lack of it in 81.5% of cases. The predictive value of the test was low in patients aged > or = 65 years and possibly those with chronic lung disease. One smoker also had a false-negative pulse oximetry result, ie, normal oxygen saturation despite radiological evidence of aspiration. CONCLUSIONS: Pulse oximetry is a reliable method of diagnosis of aspiration in most dysphagic patients. However, careful interpretation of pulse oximetry data is necessary in older subjects, possibly those with chronic pulmonary disease, and smokers. The method is noninvasive, simple, and quick, and can be used routinely in the clinical assessment of dysphagic patients.     

Contemporary diagnosis of the dysphagic patient

A variety of tests are available to aid in the diagnosis and management of dysphagia. In this article the advantages and disadvantages of many of these tests are described. Special attention is given to the videoendoscopic swallowing study (VESS). An overall treatment plan is described.     

A preliminary comparison of videofluoroscopy of swallow and pulse oximetry in the identification of aspiration in dysphagic patients

BACKGROUND: Sickle cell trait, glucose-6-phosphate dehydrogenase (G6PD) deficiency and alpha-thalassemia trait are common genetic abnormalities among the American Black population. Under oxidative stress, the presence of any of these conditions would predispose the hemoglobin (Hb) to oxidation resulting in accelerated methemoglobin (metHb) formation. It was hypothesized that red cells phenotypic for these genetic variants should have more or different levels of metHb reductase (cytochrome b5 reductase) activity. METHODS: To test this hypothesis, we measured the red cell metHb reductase activity in 558 male subjects (316 Blacks and 242 Whites), by the procedure described by Beutler. All Black patients also had G6PD spot test and Hb electrophoresis. In addition, all patients had a complete blood count (CBC). If the hematocrit was < 35% a reticulocyte count was also done. Patients with corrected reticulocyte (retic count X hematocrit/45) index over 2% were excluded regardless of other findings. RESULTS: The results showed that Blacks had different metHb reductase activity levels than Whites (mean = 3.19 vs 2.89 IU/gHb, respectively with p = 0.03). However, the differences in metHb reductase activities in patients with sickle cell trait, G6PD deficiency, and low MCV < 80 micron3 (presumptively having alpha-thalassemia) in small subgroups did not reach statistical significance (p = 0.2), although, all 3 groups were comprised of small numbers. CONCLUSIONS: It is concluded that American Blacks have significantly different metHb reductase activity. The different metHb reductase activity in Blacks seems to be unrelated to the presence of G6PD deficiency, sickle cell trait, or alpha-thalassemia and it may be the result of genetic polymorphism. However, our study samples do not exactly represent the cross-sections of the Black and White populations. In addition, all patients were male in this study. Therefore, this study should be confirmed using larger and more population-representative samples. The clinical significance of this problem is not clear at this time.     

Cerebral hemodynamics in the posterior circulation of patients with bacterial meningitis

OBJECTIVES: Stenoses of the middle and anterior cerebral artery (MCA,ACA) are a clinical relevant complication of bacterial meningitis. We examined the involvement of the posterior cerebral (PCA) and of the basilar artery (BA) into the inflammatory process. MATERIAL & METHODS: 39 unselected patients (26 men, 13 women; mean +/- SD age, 49 +/- 17 years) with bacterial (n = 37) and fungal (n = 2) meningitis underwent serial transcranial Doppler sonography recordings of the mean blood velocity (MBV) and the pulsatility index (PI) in the MCA, ACA and PCA, in the BA and in the submandibular internal carotid artery on Days 1, 3, 5, 8, 14 and 21 after admission. The results of the PCA and of the BA were compared to normal reference values and correlated to corresponding neurological signs. The criterion to assume a stenosis was: for the BA an MBV > or = 95 cm/s, for the PCA an MBV > or = 85 cm/s. RESULTS: Compared with the controls MBV in both arteries was normal on Days 1 and 8-21, but significantly increased on Days 3 and 5. The PI was significantly increased in the BA on all days and in the PCA on Days 1 and 8-21. Stenoses of the PCA (4 of 43) and of the BA (4 of 32) remained without corresponding neurological signs, and occurred only in patients with two or more narrowed arteries of the anterior circulation (p < 0.05). CONCLUSION: In bacterial meningitis, hemodynamic disturbances in the posterior circulation are less severe than in the anterior circulation and are clinically well tolerated.     

Pharyngo-UES contractile reflex in patients with posterior laryngitis

BACKGROUND: Earlier studies have shown that stimulation of the human pharynx by injection of minute amounts of water stimulates the pharyngo-UES contractile reflex. It has been suggested that this reflex may be activated during pharyngeal reflux of gastric and/or esophageal content, thus increasing the UES pressure and possibly preventing further entry of the refluxate into the pharynx. However, the integrity of this reflex in patients with posterior laryngitis has not been studied. AIM: Evaluate the pharyngo-UES contractile reflex in a group of patients with objective findings of posterior laryngitis. METHODS: Fourteen consecutive patients with posterior laryngitis (mean age, 48+/-6 y) and 13 healthy volunteers (mean age, 53+/-6 y) were studied by concurrent pharyngeal water stimulation and UES manometry. RESULTS: The threshold volume required to evoke the pharyngo-UES contractile reflex in the laryngitis group (0.4+/-0.05 mL) was significantly higher than that of the control (0.2+/-0.04 mL) (P < .05). Following stimulation of the pharyngo-UES contractile reflex, the maximum postinjection pressure in patients (75+/-6 mm Hg) was similar to that of the controls (78+/-6 mm Hg). The percent increase in UES pressure following stimulation of the reflex in the laryngitis group (99%+/-15%) was significantly higher than that of controls (55%+/-11%) (P < .05). CONCLUSIONS: Compared with normal controls, a significantly larger volume of liquid is required to trigger this reflex in patients with posterior laryngitis. When triggered, the maximum UES pressure induced by the pharyngo-UES contractile reflex is similar between the two groups. These findings suggest an altered afferent sensory limb of this reflex in patients with posterior laryngitis.     

On the constraint factor associated with the indentation of work-hardening materials with a spherical ball

It is generally accepted that the constraint factor (CF) associated with the indentation of metallic materials by a much harder indentor is in the range of 2.8 to 3.0. Invariably, the CF is assumed to have a constant value in the above range irrespective of the material indented while correlating the hardness of the material indented with its uniaxial strength properties. The objective of the present investigation is to assess the above assumption by evaluating the CF associated with the indentation process as a function of strain in the case of metallic materials exhibiting a wide range with respect to elastic modulus, strength, and strain-hardening rate. The results indicate that the CF is not really a constant but is dependent on the various material properties. The experimental CF-strain relationship observed in all of the test materials has been rationalized on the basis of elastic-plastic and fully plastic indentation models. While the theoretical models can explain the trend of the data, they are not capable of making adequately accurate quantitative predictions.     

Long posterior flap amputation in geriatric patients with ischaemic disease

A series of 165 primary amputations performed on 148 patients at Queen Mary's Hospital, Roehampton, from 1967 to 1975 is reported. The average age of these patients was 70 years, the oldest being 95. Those aged 70 years and over are considered in special detail. The problems of management of these elderly patients are complex, involving medical, surgical, and social problems. The object of treatment is to restore these patients to their previous way of life with the shortest possible time in hospital. Every patient is assessed with a view to arterial surgery, and amputation is avoided where possible by a lumbar sympathetic block or direct arterial surgery. When amputation cannot be avoided a below-knee level is selected if possible. A long posterior flap technique is used which forms a myoplasty of the gastrocnemius muscle; thus the ischaemic anterior tibial skin is avoided. Before the operation the patient is assessed by a specialist team and the management is discussed in detail. Every patient is kept in hospital until rehabilitation is achieved to the point of independence inside the home. Of the 90 patients in the group aged 70 years and over, 22% had above-knee amputations and 75% had below-knee amputations, with the result that 69% of the latter were discharged home walking. This result is contrasted with the smaller number who had an above-knee amputation. Below-knee amputation gives the elderly patient a better chance of walking because of the use of the patellar tendon bearing prosthesis. When followed up 36% of those patients with below-knee amputation were fully independent for periods exceeding six months. The price of a below-knee level of amputation is a longer hospital stay, but the quality of function and mobility obtained by the patient makes this worth while.     

Object-based inhibition of return in patients with posterior parietal damage.

Recent evidence has shown that inhibition of return, IOR, is impaired in patients with parietal damage with or without clinical signs of neglect (Bartolomeo, Sieroff, Decaix, & Chokron, 2001; Vivas, Humphreys, & Fuentes, 2003, respectively). In addition to environment-based IOR, Tipper et al. (1991) showed that IOR could be also associated with dynamic, object-based representations. In our study, we examined four patients with unilateral lesions to the parietal lobe, and a group of healthy controls, in an IOR procedure with moving objects where a pre-cued object could move, clockwise or counterclockwise, 90° in polar coordinates. The group of control participants showed a small but significant object-based IOR effect. In contrast, the patients showed an object-based IOR effect when the objects moved from the contralesional field toward the ipsilesional field, whereas there was no IOR effect when they moved from the ipsilesional to the contralesional field. These findings are discussed in terms of the role of the parietal cortex in implementing attentional biases in both environment-based (Vivas et al., 2003) and object-based frames of reference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A mathematical approximation for the solution of a static indentation test

The aim of this study was to compare the incidence of acute adverse events and long-term outcome of two different surfactant dosing procedures in respiratory distress syndrome (RDS). The effects of two surfactant dosing procedures on the incidence of transient hypoxia and bradycardia, gas exchange, ventilatory requirements and 28 d outcome were compared. The patients, comprising 102 infants (birthweight 600-2000 g) with RDS on mechanical ventilation with FiO2 > or = 0.4, were randomized at 2-24 h to receive 200 mg kg(-1) of Curosurf; in 56 it was given by bolus delivery, and in 55 by a simplified technique (dose given in 1 min via a catheter introduced through a side-hole in the tracheal tube adaptor. The baby's position was not changed and ventilation was not interrupted). Two additional surfactant doses (100 mg kg(-1)) were also given, by the same method, if ventilation with FiO2 > or = 0.3 was needed 12 and 24 h after the initial dose. The number of episodes of hypoxia and/or bradycardia was similar in both groups. A slight and transient increase in PaCO2 was observed in the side-hole group. The efficacy of the surfactant, based on oxygenation improvement, ventilator requirements, number of doses required and incidence of air leaks, was similar. No differences were observed in the incidence of intraventricular haemorrhage, patent ductus arteriosus, bronchopulmonary dysplasia or survival. In conclusion, a simplified surfactant dosing procedure not requiring fractional doses, ventilator disconnection, changes in the baby's position or manual bagging was found to be as effective as bolus delivery. The number of dosing-related transient episodes of hypoxia and bradycardia was not decreased by the slow, 1 min, side-hole instillation procedure.     

Cricopharyngeal myotomy as a method of treating cricopharyngeal dysphagia secondary to gastroesophageal reflux

Food obstruction at the cricopharyngeal level is a common symptom of gastroesophageal reflux. In selected patients, cricopharyngeal myotomy is effective in relief of symptoms. We have used myotomy in patients whose only symptom was dysphagia, in patients too debilitated for major surgery, and in patients with persistent pharyngoesophageal dysphagia following hiatal hernia repair. All were studied by barium esophagogram, endoscopy, and manometry. Radiologic aspiration of barium was apparent in five of 19 patients. High-speed manometric tracings showed intermittent cricopharyngeal incoordination in the six consecutive patients most recently studied. This finding of incoordination has been shown to be present in 38 patients with reflux and in all with major cricopharyngeal symptoms. Myotomy was effective in relieving symptoms in patients in whom this was the only reflux symptom and in the five patients too debilitated for major surgery. Good symptomatic improvement was obtained in nine of the 12 with persistent dysphagia following hernia repair, but in three relief was partial, with persistent symptoms being secondary to distal esophageal obstruction. Investigation is necessary to exclude other causes of dysphagia. However, withcareful selection, myotomy has proved to be an effective method of treatment.     

A tube in the pharynx for emergency ventilation

BACKGROUND: If the endotracheal placement of a nasal advanced tube fails, ventilation via this tube could bridge the time until a fibreoptic bronchoscope is available. This study investigates the efficiency of ventilation via a tube resting with its tip in the pharynx near the glottis. METHODS: In 20 patients respiratory data during ventilation via a pharyngeally placed tube were recorded by means of pulse oximetry, capnometry and side-stream spirometry. Results were compared with those measured previously in the same patients during conventional facemask ventilation. RESULTS: Oxygen saturation and end-tidal carbon dioxide concentration remained unchanged using ventilation via facemask (SO2 98.5 +/- 0.9%, FECO2 4.5 +/- 0.7 vol%) or pharyngeal tube (SO2 98.6 +/- 0.7%, FECO2 4.8 +/- 0.4 vol%). No significant differences were found between the two groups with regard to peak airway pressure, tidal volume leakage, compliance and resistance of the respiratory system. CONCLUSIONS: Our results suggest an effective ventilation and oxygenation via a tube placed with its tip in the pharynx. This technique may be helpful during difficult and prolonged nasal intubation.     

Videokeratographic abnormalities in a family with posterior polymorphous dystrophy

Data obtained suggest the existence of regulation mechanism controlling parameters of thyroid status, that does not require any modification of thyroid gland secretory function. The realisation of this mechanism can involve hormone-depositing function of blood erythrocytes, which is sensitive to a) change of regional or systemic pH and b) change of hematocrit. Results of the present study indicate that mammalian erythrocytes are able to bind considerable quantities of T3 and T4 and, T3 binding is preferable.     

Coordination of peristalsis in pharynx and esophagus

When a swallowed liquid bolus is followed from mouth to stomach in man by contrast studies or manometry, it traverses its course without hesitation even though the bolus is propelled by striated muscle contraction in the first part of its journey and smooth muscle in the latter part. The striated muscle is innervated by excitatory cholinergic nicotinic cranial nerves whereas the smooth muscle of the esophagus is innervated by the enteric nervous system (ENS) through excitatory and inhibitory nerves. These differences can be demonstrated by observing the inhibitory effects of curare and atropine, the first blocking nicotinic receptors and the second muscarinic receptors. Early students of esophageal motility recognized that peristalsis could be initiated in two ways. The first is initiated by a swallow and is called primary peristalsis and the second called secondary peristalsis is initiated by distension of the esophagus. It was proposed that primary peristalsis was initiated by a single sensory input activated by the bolus entering the pharynx which in turn activated a motor program in the brain stem. Secondary peristalsis was believed to be stimulated by multiple afferent impulses arriving from the esophagus as the bolus passed down the esophagus. More recent studies using manometric techniques have suggested that the only difference between primary and secondary peristalsis is the afferent stimuli and the effector mechanism is the same. Subsequent studies of carefully timed, paired swallows, transection of vagus nerves and esophagus, and single nerve recordings suggest that the answer lies between the two extremes noted above.(ABSTRACT TRUNCATED AT 250 WORDS)     

Corneal endothelium in patients with diabetes after extracapsular cataract extraction with intraocular lens implantation in the posterior chamber

We have examined endothelial cell density before and 3, 6, 12 months after extracapsular cataract extraction with intraocular lens implantation (posterior chamber) in diabetic patients and in non-diabetics. We have not found statistically significant differences between the mean loss of endothelial cells due to surgery in diabetic and non-diabetic patients.