Endoscopic transnasal approach and intraoperative navigation for the treatment of isolated blowout fractures of the medial orbital wall.

The aim of this study is to describe the reduction of medial orbital wall fractures using a combination of two different techniques: the endoscopic reduction and the navigation aided reconstruction. The endoscopic approach avoids an external incision and allows the observation of the fracture site clearly. Navigation-aided reconstruction is essential to achieve precise and predictable results in orbital reconstruction. It consists in an ideal virtual reconstruction of the target area created using a mirroring tool, and superimposing and comparing the unaffected and the affected sides. This technique opens a broad spectrum of possible surgical approaches, especially in situations in which anatomical landmarks for precise positioning of bone fragments, or bone grafts, are missing. This study is the first to combine these two techniques. The study was carried out in seven patients who underwent endoscopic reduction of isolated blowout fractures of the medial orbital wall and navigation-aided reconstruction at the authors' institution. This pilot study clearly shows that a combination of the endoscopic reduction and the navigation-aided reconstruction provides functional results and great advantages in terms of anatomical preservation and postoperative morbidity.

Endoscopic laser-assisted dacryocistorhinostomy DCR with the placement of a customised silicone and Teflon bicanalicular stent Endoscopic laser-assisted dacryocystorhinostomy (DCR).

INTRODUCTION: We present our experience in endoscopic laser assisted dacryocystorhinostomy (DCR) analyzing the results obtained with a new technique that involves placing bicanalicolar silicone stent more Teflon tube, in combination with paraseptal silastic sheet. MATERIALS AND METHODS: In our study 49 of 57 patients (85%) at a mean follow up of at least 12 months have not reported epiphora or more episodes of acute dacryocystitis. RESULTS: 49 out of the 57 patients (85%) in our group reported no additional epiphora or episodes of acute dacryocystitis. CONCLUSIONS: Endoscopic DCR is currently the gold standard for sac and post-sac stenosis given the minimal invasiveness of the procedure and the long-term results that appear comparable to those obtained with extrinsic DCR. The principal problem is cicatricial stenosis that can occlude the stoma over time.

Effects of contralateral white noise stimulation on distortion product otoacoustic emissions in myasthenic patients.

Myasthenia gravis (MG) induces a reduction of transient evoked otoacoustic emissions (TEOAEs) and distortion product otoacoustic emissions (DPOAEs) that reverses partially after administration of an acetylcholinesterase (AChE) inhibitor. In normal subjects a contralateral acoustic stimulation (CAS) produces an amplitude reduction of TEOAEs and DPOAEs. This effect, called contralateral suppression (CS), is mediated by the efferent auditory system. Twenty subjects affected by MG underwent DPOAE recording with and without contralateral white noise in a drug-free baseline period ('basal') and 1 h ('post') after administration of a reversible AChE inhibitor. In 'basal' condition CAS did not induce significant DPOAE amplitude changes but a paradoxical slight increase was observed. After drug administration, CAS produced a significant decrease of DPOAE amplitudes for middle frequencies (f(2) between 1306 and 2600 Hz). In normal controls CAS caused a significant decrease (P<0.001) for all frequencies. The amount of CS in controls and in the MG 'post' condition was not significantly different. The increased acetylcholine (ACh) availability following drug consumption seems to partially restore outer hair cell function and enhances their electromotility; a further influx of ACh due to CAS yields to restoration of the CS. These findings also suggest that DPOAEs may be useful in the diagnosis of MG and for monitoring the effectiveness of treatment.

Postural control and glycerol test in Ménière's disease.

Ménière's disease is a clinical disorder, characterized by fluctuating hearing loss, recurrent spontaneous episodic vertigo, tinnitus and aural fullness, which may be defined as the idiopathic syndrome of endolymphatic hydrops. The most important test for diagnosis of Ménière's disease is the glycerol test. This is a simple and rapid method and several authors have confirmed its efficiency for identifying endolymphatic hydrops. This test provides information on the cochlear response to the osmotic changes produced by glycerol in the inner ear, whereas modifications in the vestibular labyrinth are usually not evaluated. The aim of this study was to evaluate the effects of glycerol on postural control during attacks of Ménière's disease, and to correlate this data with data on cochlear function. After the glycerol test, an improvement in postural control was recorded in 70% of patients, with all patients reporting a recovery of vertigo. The impairment of postural control during endolymphatic hydrops could be related to a pressure increase in the labyrinth, which interferes with the normal dynamics of the endolymph, and a rapid functional recovery could occur during an osmotic depletion. Dynamic posturography improves the sensitivity of the glycerol test and may therefore be useful in the diagnosis and staging of Ménière's disease.

The role of cholinergic transmission in outer hair cell functioning evaluated by distortion product otoacoustic emissions in myasthenic patients.

Outer hair cells (OHCs) are the source of otoacoustic emissions, following a tropomyosin-miosin-dependent contraction, which are regulated by the olivocochlear bundle via the release of acetylcholine (ACh). ACh acts on ACh receptors (AChR) located on the OHC post-synaptic membrane. In myasthenia gravis (M.G.) neuromuscular transmission is reduced due to the action of AChR autoantibodies. It has previously been shown that M.G. induces a reduction in transient evoked otoacoustic emissions (TEOAEs), which is reversed after administration of a cholinesterase (AChE) inhibitor. Distortion product otoacoustic emissions (DPOAEs) were recorded before and 60 min after oral administration of 60 mg pyridostigmine bromide in 25 patients with normal hearing affected by M.G. The results were compared with those from 25 age-matched normal controls. Mean values of DPOAE amplitude in myasthenic patients were significantly (p < 0.05) lower at all frequencies before drug administration. All patients showed an overall significant (p < 0.05) increase in DPOAE amplitude after drug administration, although without reaching the control values. Such a recovery was more evident and highly significant (p < 0.01) for middle and high frequencies and could be explained by a higher concentration of ACh receptors in the basal and middle cochlear turns. These data seem to confirm the role of ACh in the neurotransmission of the auditory efferent system and may represent a new in vivo model for the investigation of the physiology of this system.

[Difficulties in the clinical, radiological and therapeutic evaluation of the initial stage of mucormycosis of the rhinosinus]. / Difficoltà nella valutazione clinica, radiologica e terapeutica della mucormicosi rino-orbitaria in fase iniziale.

The initial diagnosis and subsequent treatment of rhino-orbital mucormycoses is quite difficult, particularly because the patient may find it difficult to accept aggressive therapeutic protocols, even when free of any endocranial involvement. The authors draw inspiration from a clinical case of rhino-orbital mucormycosis in a patient suffering from decompensated type I diabetes mellitus to discuss the main clinical-diagnostic and therapeutic aspects of this disorder. Timely medical-surgical treatment proves extremely important for prognosis, preventing the intracranial extension of the lesion which is the cause of death in 80% of such cases. As regards the diagnostic protocol, careful clinical, radiological monitoring with CT and NMR--in strict interdisciplinary cooperation between otorhinolaryngologist, radiologist, ophthalmologist, microbiologist and histopathologist--is especially important. Radical surgery, at times demolition, associated with correction of the metabolic decompensation, systemic therapy with Amphotericin B and localbi-weekly medication for three months constitutes the best therapeutic protocol for treatment of this disorder.