Robotics in ear, nose and throat (ENT) surgery

The three main classes of robotics in ear, nose and throat (ENT) surgery (telemanipulation, image-guided functional servoing, and computer numerical control) are discussed and important examples of applications are described to show both technological and clinical developments. As access to many anatomical features of the head requires very small and compact tools to accurately perform procedures, examples are give in ear surgery where manipulation of the minute ossicles requires fine, dexterous movements.

Iatrogenic atrial septal defect, erosion of the septum primum after device closure of a patent foramen ovale as a new medical entity

Iatrogenic atrial septal defects are described in 2 patients. They occurred after implantation of Amplatzer occluders to close a patent foramen ovale. While device erosions to the extra-atrial space have been described, erosion induced atrial septal defects are a new medical entity. They may be fairly common in the situation of an atrial septal aneurysm whipping the rim of the device incessantly. They are clinically silent and benign and require echocardiography for detection. A second device solved the problem in the cases described.

Reorganization of CA3 area of the mouse hippocampus after pilocarpine induced temporal lobe epilepsy with special reference to the CA3-septum pathway

We showed that when CA3 pyramidal neurons in the caudal 80% of the dorsal hippocampus had almost disappeared completely, the efferent pathway of CA3 was rarely detectable. We used the mouse pilocarpine model of temporal lobe epilepsy (TLE), and injected iontophoretically the anterograde tracer phaseolus vulgaris leucoagglutinin (PHA-L) into gliotic CA3, medial septum and the nucleus of diagonal band of Broca, median raphe, and lateral supramammillary nuclei, or the retrograde tracer cholera toxin B subunit (CTB) into gliotic CA3 area of hippocampus. In the afferent pathway, the number of neurons projecting to CA3 from medial septum and the nucleus of diagonal band of Broca, median raphe, and lateral supramammillary nuclei increased significantly. In the hippocampus, where CA3 pyramidal neurons were partially lost, calbindin, calretinin, parvalbumin immunopositive back-projection neurons from CA1-CA3 area were observed. Sprouting of Schaffer collaterals with increased number of large boutons in both sides of CA1 area, particularly in the stratum pyramidale, was found. When CA3 pyramidal neurons in caudal 80% of the dorsal hippocampus have almost disappeared completely, surviving CA3 neurons in the rostral 20% of the dorsal hippocampus may play an important role in transmitting hyperactivity of granule cells to surviving CA1 neurons or to dorsal part of the lateral septum. We concluded that reorganization of CA3 area with its downstream or upstream nuclei may be involved in the occurrence of epilepsy.

Endoscopic scoring of the tracheal septum in horses and its clinical relevance for the evaluation of lower airway health in horses

REASONS FOR PERFORMING STUDY: Although endoscopic scoring of the tracheal septum thickness is used as a diagnostic tool for evaluation of lower airway disease, its clinical relevance and reliability have never been critically assessed in the horse. OBJECTIVES: To investigate if septum thickness scores (STS) are reliable and serve as a clinically useful indicator of lower airway disease status and/or inflammation. METHODS: The variance of STS attributable to the horse, observer and changes over time was determined. The distribution of STS in a population of clinically normal horses and correlations of STS with age, gender, as well as mucus accumulation and cell differentials of tracheobronchial secretions and bronchoalveolar lavage fluid were investigated. Effects of altered pulmonary ventilation, induced by different drugs, on STS were assessed. Finally, STS of horses affected with recurrent airway obstruction (RAO) were compared to those of clinically normal horses. RESULTS: Recorded STS showed excellent intra- and satisfactory interobserver agreement Established clinical, endoscopic and cytological measures of lower airway inflammation, i.e. mucus accumulation scores and airway neutrophilia, did not correlate with STS. In horses age > or = 10 years, septum scores were significantly higher (P = 0.022) than in younger horses. Septum thickness scores did not differ significantly between clinically normal and RAO-affected horses both in exacerbation and in remission. Horses with markedly increased breathing effort (i.e. with metacholine- or lobeline hydrochloride-challenge), often differed markedly (up to 1.9 scores), but the average of end-inspiratory and end-expiratory STS did not differ from baseline STS. CONCLUSIONS AND CLINICAL RELEVANCE: Endoscopic STS are a reproducible measure, but STS did not correlate with clinical, endoscopic and cytological findings indicative of RAO or inflammatory airway disease.

Is alcohol ablation of the septum associated with recurrent tachyarrhythmias?

QUESTIONS UNDER STUDY: Alcohol ablation (AA) of the septum has been introduced as new therapy in hypertrophic cardiomyopathy (HCM). It was feared that iatrogenic myocardial infarction due to AA may induce re-entry tachyarrhythmias and increase sudden cardiac death. METHODS AND RESULTS: Twenty-four patients (mean age 52 years) underwent successful AA. Clinical follow-up (FU) ranged from 0.3 to 0.7 years (mean 2.8). One patient died (suicide) 4 years after AA. Left ventricular (LV) outflow gradient (peak-to-peak) decreased (median) after AA from 43 (IQR 25 to 4) mmHg to 1 (IQR 0 to 12) mmHg (rest) (p <0.001) and from 130 (IQR 75 to 165) mmHg to 13 (IQR 0 to 31) mmHg (postextrasystolic) (p <0.001). Transient AV block occurred in 22% (5/24) necessitating temporary pacing. A permanent pacemaker was implanted in 4% (1/24). NYHA-class was 2.5 (IQR 2.0 to 3.0) before and 1.5 (IQR 1.3 to 2.0) (p <0.001) after AA. During FU, 2 pacemakers were implanted due to bradycardia (no AV block). A right bundle branch block was found in 13% (2/24) before and 46 % (11/24) after AA (p = 0.003). Non-sustained ventricular tachycardia (NSVT) was observed in 13% (2/16) before and 22% (5/23) (p = 0.46) after AA. Two patients required ICD implantation. CONCLUSIONS: Long-term FU is excellent in HCM after AA. The pressure gradient drops below 25 mm Hg in 95% (23/24) of all patients. Transient AV block occurs in 22% (5/24), but permanent pacemaker implantation is rarely needed (13%, 2/24). Severe NSVT occurs in 13% (2/16) before and 22% (5/23) after AA but ICD implantation is only occasionally required.

Development of the premature infant nose throat-model (PrINT-Model): an upper airway replica of a premature neonate for the study of aerosol delivery

Clinical efficacy of aerosol therapy in premature newborns depends on the efficiency of delivery of aerosolized drug to the bronchial tree. To study the influence of various anatomical, physical, and physiological factors on aerosol delivery in preterm newborns, it is crucial to have appropriate in vitro models, which are currently not available. We therefore constructed the premature infant nose throat-model (PrINT-Model), an upper airway model corresponding to a premature infant of 32-wk gestational age by three-dimensional (3D) reconstruction of a three-planar magnetic resonance imaging scan and subsequent 3D-printing. Validation was realized by visual comparison and comparison of total airway volume. To study the feasibility of measuring aerosol deposition, budesonide was aerosolized through the cast and lung dose was expressed as percentage of nominal dose. The airway volumes of the initial magnetic resonance imaging and validation computed tomography scan showed a relative deviation of 0.94%. Lung dose at low flow (1 L/min) was 61.84% and 9.00% at high flow (10 L/min), p < 0.0001. 3D-reconstruction provided an anatomically accurate surrogate of the upper airways of a 32-wk-old premature infant, making the model suitable for future in vitro testing.

Teratoma of the nasal septum in a neonate: an endoscopic approach

Initial presentation of a white female newborn delivered after normal pregnancy demonstrated a white mass obstructing the left nare. Primary biopsy revealed a focus of fibrotic nasal mucosa that included squamous and respiratory epithelium. After endoscopic resection of the mass, histopathologic examination resulted in the diagnosis of a teratoma. According to our literature review, this is the first case of a teratoma arising from the nasal septum in a white. Worldwide, 3 additional cases have been reported, but none included endoscopic management. This case illustrates our protocol for an endoscopic approach to an obstructive nasal mass in a neonate and our experience in the management of this rare disease.

Composite skin grafts for basal cell carcinoma defects of the nose

Basal cell carcinoma is the most frequent cutaneous cancer of the nose and is characterized by its local spreading and exceptionally rare tendency to metastasize. Since a significant advantage has been seen in surgery compared to other treatments, surgical excision ensuring the highest chance of cure is frequently employed. Excision defects of the nose may be covered with either local flap or a full-thickness skin graft. In resurfacing such defects following excision of basal cell carcinomas, we favor the technique of composite-skin grafting which involves the harvesting of composite-skin graft including the epidermis, dermis and superficial layers of subcutaneous tissue to obtain the required thickness in the recipient site. This technique was used for defects remaining after the excision of basal cell carcinomas in a series of 15 patients. The areas involved were lateral nasal region (5 cases), nasal tip (4 cases), dorsum (3 cases), alar lobule (2 cases), and soft triangle (1 case). The mean follow-up was 14.2 months. The color, texture and thickness of the composite-skin graft harvested from the preauricular site and the neck compare favorably with the skin of the nose region. Satisfactory results, both clinically and in patient appreciation, have been obtained in both the reconstruction site and the appearance of the donor site in all patients.

Impact of cardiac computed tomography of the interatrial septum before pulmonary vein isolation

BACKGROUND Multidetector computed tomography (MDCT) may be useful to identify patients with patent foramen ovale (PFO). The aim of this study was to analyze whether a MDCT performed before pulmonary vein isolation reliably detects a PFO that may be used for access to the left atrium. METHODS AND RESULTS In 79 consecutive patients, who were referred for catheter ablation of symptomatic paroxysmal or persistent atrial fibrillation (AF), the presence of a PFO was explored by MDCT and transesophageal echocardiography (TEE). TEE was considered as the gold standard, and quality of TEE was good in all patients. In 16 patients (20.3%), MDCT could not be used for analysis because of artifacts, mainly because of AF. On TEE, a PFO was found in 15 (23.8%) of the 63 patients with usable MDCT. MDCT detected six PFO of which four were present on TEE. This corresponded to a sensitivity of 26.7%, a specificity of 95.8%, a negative predictive value of 80.7%, and a positive predictive value of 66.7%. The receiver operating characteristics curve of MDCT for the detection of PFO was 0.613 (95% confidence interval 0.493-0.732). CONCLUSIONS MDCT may detect a PFO before pulmonary isolation. However, presence of AF may lead to artifacts on MDCT impeding a meaningful analysis. Furthermore, in this study sensitivity and positive predictive value of MDCT were low and therefore MDCT was not a reliable screening tool for detection of PFO.