Cerebrospinal Fluid Leak During Stapes Surgery: The Importance of Temporal Bone CT Reconstructions in Oblique Anatomically Oriented Planes.

Stapes gusher is a massive flow of perilymph and cerebrospinal fluid leak that fills the middle ear immediately after surgical opening of the labyrinth, such as during stapedectomy. Stapes gusher usually occurs as the result of a congenital malformation that causes an abnormal communication between the perilymphatic space and the subarachnoid space involving the internal auditory canal or the cochlear duct. To date, the potential risk of stapes gusher cannot be assessed preoperatively, as there are not pathognomonic signs suggestive of this complication. However, high-resolution computed tomography scan (HRCT) of the temporal bone can provide information that may help recognizing patients at risk. Recently, an anatomic evaluation of the inner ear with oblique reformation at HRCT has been described. This reformation offers a new and more detailed topographic vision of temporal bone structures compared to the classic axial and coronal planes and may help identifying anatomical alterations otherwise not visible. In this article, we present a case of stapes gusher and the role of preoperative HRCT with oblique reformation in its prevention.

Differential modulation of CXCL8 versus CXCL10, by cytokines, PPAR-gamma, or PPAR-alpha agonists, in primary cells from Graves' disease and ophthalmopathy.

BACKGROUND: Thyrocytes secrete CXC chemokines, particularly (C-X-C motif) ligand (CXCL)8 and CXCL10; its physiopathological significance remains unclear. This study investigates the modulation of the secretion of CXCL8 vs. CXCL10, in human primary cells cultures of thyroid follicular cells (TFC) in Graves' disease (GD), and fibroblasts (OF) or preadipocytes (OP) from Graves' ophthalmopathy (GO). METHODS: Cells were initially incubated with different concentrations of tumor necrosis factor (TNF)α (1, 5, 10 ng/mL). Then, CXCL8 and CXCL10 were measured in the supernatants of TFC, OF or OP cells basally and after 24 h of treatment with interferon (IFN)γ (1000 IU/mL) and/or TNFα (10 ng/mL), in presence/absence of the peroxisome proliferator activated receptor (PPAR)γ agonist pioglitazone (0, 0.1, 1, 5, 10, 20 µM), or the PPARα agonist fenofibrate (5, 10, 50, 100 µM). RESULTS: CXCL8, not CXCL10, was detected in basal conditions in TFC, OF and OP. CXCL8 secretion increased dose-dependently with increasing concentrations of TNFα. CXCL10 secretion was significantly stimulated by IFNγ (P < 0.01) and not by TNFα, whereas CXCL8 was induced by TNFα (P < 0.01), and inhibited by IFNγ (P < 0.01) in TFC, OF and OP. Combining TNFα and IFNγ, the IFNγ-induced CXCL10 secretion was synergistically increased (P < 0.01) while the TNFα-induced CXCL8 secretion (P < 0.01) was reversed in all cell types. Pioglitazone had no significant effect on the secretion of CXCL8 stimulated by TNFα, while inhibited CXCL10. Fenofibrate, in presence of IFNγ plus TNFα, dose-dependently inhibited both CXCL10 and CXCL8 release. CONCLUSION: We first show that TFC, OF, and OP secrete CXCL8 and CXCL10 differentially, sustained by specific proinflammatory cytokines or their combination. This could reflect a different role of the two chemokines in the course of the disease, as CXCL10 could be associated with the initial phase of the disease when IFNγ is preponderant, while CXCL8 could be associated with a later chronic phase of the disease, when TNFα prevails.

Extra-ocular muscle cells from patients with Graves' ophthalmopathy secrete α (CXCL10) and ß (CCL2) chemokines under the influence of cytokines that are modulated by PPARγ.

To our knowledge, no study has evaluated the involvement of T helper (Th)1- and Th2-chemokines in extra-ocular muscle (EOM) myopathy in "patients with thyroid-associated ophthalmopathy" (TAO-p). We tested the effects of interferon (IFN)γ and tumor necrosis factor (TNF)α stimulation, and of increasing concentrations of peroxisome proliferator-activated receptor (PPAR)γ agonists (pioglitazone or rosiglitazone; 0.1 µM-20 µM), on Th1-chemokine [C-X-C motif ligand (CXCL)10] and Th2-chemokine [C-C motif ligand (CCL)2] secretion in primary EOM cultures from TAO-p vs. control myoblasts. Moreover, we evaluated serum CXCL10 and CCL2 in active TAO-p with prevalent EOM involvement (EOM-p) vs. those with prevalent orbital fat expansion (OF-p). Serum CXCL10 was higher in OF-p and EOM-p vs. controls, while serum CCL2 was not significantly different in controls, or in OF-p and EOM-p. We showed the expression of PPARγ in EOM cells. In primary EOM cultures from TAO-p: a) CXCL10 was undetectable in the supernatant, IFNγ dose-dependently induced it, whereas TNFα did not; b) EOM produced basally low amounts of CCL2, TNFα dose-dependently induced it, whereas IFNγ did not; c) the combination of TNFα and IFNγ had a significant synergistic effect on CXCL10 and CCL2 secretion; and d) PPARγ agonists have an inhibitory role on the modulation of CXCL10, while they stimulate CCL2 secretion. EOM participates in the self-perpetuation of inflammation by releasing both Th1 (CXCL10) and Th2 (CCL2) chemokines under the influence of cytokines, in TAO. PPARγ agonist activation plays an inhibitory role on CXCL10, but stimulates the release of CCL2.

Assessment of skin microvascular endothelial function in patients with acute unilateral vestibular syndrome.

Abnormalities in labyrinth vasculature, resulting in labyrinth ischemia may be responsible for acute unilateral vestibular syndrome (AVS). However, since no tools for the study of the labyrinth microvasculature are available in clinical settings, labyrinth microvascular abnormalities in AVS patients (AVS-pts) can only be hypothesized on the basis of the their cardiovascular risk profile. Considering that skin microcirculation may mirror vascular function in other body districts, we examined skin endothelial function in 20AVS-pts and in 20 healthy control subjects (CS), with the aim of predicting labyrinth microvascular abnormalities in the same AVS-pts, potentially involved in the pathogenesis of their AVS. AVS-pts and CS underwent laser-Doppler flowmetry measurement of the skin forearm vasodilator response (SVR) to iontophoresis of the endothelial-dependent vasodilator acetylcholine (ACh) and to the endothelial-independent vasodilator sodium nitroprusside (SNP). SVR to ACh was significantly lower than to SNP in AVS patients (p < 0.005, ANOVA for repeated measures), consistent with skin endothelial dysfunction, while no significant differences in SVR between ACh and SNP were observed in CS. Accordingly with an arbitrary cut-off of 30% or greater reduction in SVR to ACh compared to SNP, endothelial dysfunction was found in 4 (20%) of CS, and in 14 (70%) of AVS-pts (6 with associated co-morbidities potentially responsible for endothelial dysfunction, and 8 without these co-morbodities). This study shows that the investigation of skin endothelial function in AVS-pts may be helpful in identifying AVS-pts in whom an ischemic origin of AVS might be more probable, in spite of their low cardiovascular risk profile.

Intratympanic treatment of intractable unilateral Meniere disease: gentamicin or dexamethasone? A randomized controlled trial.

OBJECTIVE: To determine the efficacy and safety of low-dose intratympanic gentamicin (ITG) compared with intratympanic dexamethasone (ITD) in patients with intractable unilateral Ménière disease (MD). STUDY DESIGN: Open prospective randomized controlled study. SETTING: Tertiary referral center. SUBJECTS AND METHODS: Sixty patients affected by definite unilateral MD were enrolled between January 1, 2007, and June 30, 2008. Thirty-two patients were treated with a buffered gentamicin solution injected in the middle ear (maximum of 2 injections); 28 patients were treated with ITD (4 mg/mL, 3 injections at intervals of 1 every 3 days). Mean outcome measurements consisted of control of vertigo attacks, pure tone average (PTA), speech discrimination score, functional disability score, and statistical analysis using repeated measures analysis of variance. RESULTS: In the ITG group at 2-year follow-up, complete control of vertigo (class A) was achieved in 26 patients (81%) and substantial control of vertigo (class B) in 4 patients (12.5%). In the ITD group, class A was achieved in 12 (43%), and class B in 5 (18%) patients. In the gentamicin group, 4 patients showed a reduction in PTA of ≥10 dB. In the ITD group, PTA was unchanged or slightly improved in 16 patients (belonging to class A-B) and worse in 12. CONCLUSIONS: Low-dose ITG achieved better outcome than ITD in the control of vertigo attacks in patients suffering from unilateral MD, with a very low incidence of hearing deterioration. ITD offers poorer vertigo control rate, and hearing preservation is achieved only in cases with no vertigo recurrences.

Cytokines (interferon-γ and tumor necrosis factor-α)-induced nuclear factor-κB activation and chemokine (C-X-C motif) ligand 10 release in Graves disease and ophthalmopathy are modulated by pioglitazone.

Until now, the following are not known: (1) the mechanisms underlying the induction of chemokine (C-X-C motif) ligand 10 (CXCL10) secretion by cytokines in thyrocytes; (2) if pioglitazone is able, like rosiglitazone, to inhibit the interferon (IFN)-γ-induced chemokine expression in Graves disease (GD) or ophthalmopathy (GO); and (3) the mechanisms underlying the inhibition by thiazolidinediones of the cytokines-induced CXCL10 release in thyrocytes. The aims of this study were (1) to study the mechanisms underlying the induction of CXCL10 secretion by cytokines in GD thyrocytes; (2) to test the effect of pioglitazone on IFNγ-inducible CXCL10 secretion in primary thyrocytes, orbital fibroblasts, and preadipocytes from GD and GO patients; and (3) to evaluate the mechanism of action of thiazolidinediones on nuclear factor (NF)-κB activation. The results of the study (1) demonstrate that IFNγ + TNFα enhanced the DNA binding activity of NF-κB in GD thyrocytes, in association with the release of CXCL10; (2) show that pioglitazone exerts a dose-dependent inhibition on IFNγ + TNFα-induced CXCL10 secretion in thyrocytes, orbital fibroblasts, and preadipocytes, similar to the effect observed with rosiglitazone; and (3) demonstrate that thiazolidinediones (pioglitazone and rosiglitazone) act by reducing the IFNγ + TNFα activation of NF-κB in Graves thyrocytes. To the best of our knowledge, this is the first study showing that cytokines are able to activate NF-κB in Graves thyrocytes and a parallel inhibitory effect of pioglitazone both on CXCL10 chemokine secretion and NF-κB activation. Future studies will be needed to verify if new targeted peroxisome proliferator-activated receptor-γ activators may be able to exert the anti-inflammatory effects without the risk of expanding retrobulbar fat mass.

64-row MDCT perfusion of head and neck squamous cell carcinoma: technical feasibility and quantitative analysis of perfusion parameters.

OBJECTIVES: To evaluate the technical feasibility of 64-row computed tomography (CT) quantitative perfusion imaging of head and neck squamous cell carcinoma (SCC). METHODS: Twenty-nine patients with a total of 29 pathologically proven SCC underwent a cine-mode CT perfusion acquisition covering the lesion site. The acquisition started 10 s after intravenous injection of iodinated contrast material and lasted 50 s. On a dedicated workstation, regions of interest (ROI) were traced within the SCC, on a healthy portion of tissue (H), and on the ipsilateral sternocleidomastoid muscle (M). Blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability-surface product (PS) were calculated. RESULTS: In SCC, BF, BV and PS were higher compared with H (p<0.0001, p=0.002 and p=0.004, respectively) and M (p<0.0001). Conversely, MTT was lower in SCC than in H (p=0.0009) and M (p=0.0003). All datasets were free from substantial motion artefacts and ROI misregistration phenomena. No substantial discomfort or adverse events were experienced by any of the patients. CONCLUSION: 64-row CT quantitative perfusion imaging allows head and neck SCC to be distinguished from normal tissues.

Monokine induced by interferon gamma (IFNgamma) (CXCL9) and IFNgamma inducible T-cell alpha-chemoattractant (CXCL11) involvement in Graves' disease and ophthalmopathy: modulation by peroxisome proliferator-activated receptor-gamma agonists.

CONTEXT: CXC alpha-chemokine CXCL10/IP-10 plays an important role in the initial phases of Graves' ophthalmopathy (GO). Human thyrocytes, orbital fibroblasts, and preadipocytes are stimulated to produce CXCL10 when treated with interferon gamma (IFNgamma) and TNFalpha. Peroxisome proliferator-activated receptor-gamma (PPARgamma) activation plays an inhibitory role in this process. OBJECTIVE: Until now, no data are present in literature about the involvement of CXCL9 and CXCL11 in Graves' disease and GO, or of PPARgamma activators' effect on these chemokines. METHODS: It has been studied how IFNgamma and TNFalpha stimulation and PPARgamma activation affect CXCL9 and CXCL11 secretion in primary cultures of thyrocytes, orbital fibroblasts, and preadipocytes. RESULTS: In primary cultures of thyrocytes, retrobulbar fibroblasts, and retrobulbar preadipocytes obtained from GO patients, CXCL9 and CXCL11 production was absent under basal conditions; CXCL9 and CXCL11 secretion was not induced by TNFalpha alone, whereas it was dose dependently stimulated treating cells with IFNgamma. The treatment with TNFalpha plus IFNgamma has a synergistic effect on CXCL9 and CXCL11 release. Treating all cell types with the PPARgamma agonist, rosiglitazone, or pioglitazone, the IFNgamma plus TNFalpha-induced CXCL9 and CXCL11 release was dose dependently (0.1-20 microm) suppressed. CONCLUSIONS: We conclude that thyrocytes and retrobulbar cell types from patients with Graves' disease and ophthalmopathy participate in the self-perpetuation of inflammation, releasing CXCL9 and CXCL11 chemokines when stimulated with cytokines. PPARgamma activation plays an inhibitory role in this process. The huge response of CXCL9 to the IFNgamma plus TNFalpha-stimulation suggests its leading role among CXC chemokines.

Parapharyngeal cyst: considerations on embryology, clinical evaluation, and surgical management.

Branchial cleft anomalies represent a common cause of cervical mass in adults. Describing a case report, we reviewed embryology, clinical elements, and treatment options for parapharyngeal congenital cysts. A case of a parapharyngeal cyst mimicking a tonsillar abscess is presented. A second branchial cleft cyst was hypothesized on a clinical and radiologic basis and then confirmed by histologic data. Magnetic resonance imaging provided fundamental information for the study of the parapharyngeal mass and its relationship with surrounding structures. In literature, surgical excision is the recommended therapy. We removed the cyst through a transcervical approach, with no complications or recurrence after 3 years. In our opinion, cervicotomy should be considered the gold standard approach, even for lesions not palpable in the cervical area. When dealing with a parapharyngeal cyst, second branchial cleft anomalies should be considered. Our experience confirms that cervicotomy is a safe approach to parapharyngeal congenital lesions.

Interferon-gamma-inducible alpha-chemokine CXCL10 involvement in Graves' ophthalmopathy: modulation by peroxisome proliferator-activated receptor-gamma agonists.

CONTEXT: CXC alpha-chemokine CXCL10/inducing protein-10 play an important role in the initial phases of autoimmune thyroid disorders. Human thyrocytes in primary culture produce large amounts of CXCL10 when stimulated by interferon-gamma (IFNgamma) and TNFalpha. OBJECTIVE: Serum CXCL10 levels (sCXCL10) were measured in patients with active or inactive Graves' ophthalmopathy (GO). The effects of IFNgamma and TNFalpha stimulation and peroxisome proliferator-activated receptor-gamma (PPARgamma) activation on CXCL10 secretion in primary cultures of thyrocytes, orbital fibroblasts, and preadipocytes were tested. PATIENTS: Sixty consecutive patients with Graves' disease, 60 age- and sex-matched patients with GO, and 60 controls were studied. RESULTS: sCXCL10 was higher (P < 0.0001) in Graves' disease (120 +/- 83 pg/ml; n = 60) and GO (122 +/- 71; n = 60) patients than in age- and sex-matched euthyroid controls (72 +/- 32; n = 60). Among GO patients, sCXCL10 levels were significantly higher in those (n = 14) with active disease (171 +/- 197) than in those with inactive disease (114 +/- 45 pg/ml; P < 0.003). In primary cultures of thyrocytes, retrobulbar fibroblasts and retrobulbar preadipocytes from GO patients, CXCL10 production was absent under basal conditions; dose-dependent secretion of CXCL10 was not induced by TNFalpha alone, whereas stimulation with IFNgamma or TNFalpha plus IFNgamma induced CXCL10 release. Treatment of all cell types with the PPARgamma agonist, rosiglitazone, dose-dependently (0.1-10 microm) suppressed IFNgamma- plus TNFalpha-induced CXCL10 release. CONCLUSIONS: We conclude that in GO, thyrocytes and retrobulbar cell types participate in the self-perpetuation of inflammation by releasing chemokines under the influence of cytokines. PPARgamma activation plays an inhibitory role in this process.

Transtympanic gentamicin and fibrin tissue adhesive for treatment of unilateral Menière's disease: effects on vestibular function.

OBJECTIVE: To determine the effects of transtympanic injections, with a mixture composed of gentamicin and fibrin tissue adhesive (FTA), on vestibular function of patients with intractable unilateral Menière's disease. STUDY DESIGN: This was an open, prospective study. SETTING AND PATIENTS: The study was performed at 2 tertiary referral centers. Twenty-six patients affected by "definite" unilateral Menière's disease, unresponsive to medical therapy for at least 6 months, were enrolled. INTERVENTION: A buffered gentamicin solution mixed with FTA was injected in the middle ear until the development of bedside vestibular hypofunction signs and/or caloric weakness in the treated ear. MAIN OUTCOME MEASURE: Vestibular function was evaluated by 3 bedside vestibular tests (observation of spontaneous nystagmus, head shaking test, and head thrust test) and by a caloric test. Tests were performed on days 10 and 30 after completion of treatment. Tests were also performed 3, 6, and 12 months from completion of the gentamicin-FTA protocol. The effects of treatment were also assessed in terms of hearing levels, control of vertigo, and disability status. RESULTS: In 22 of the 26 patients, only 1 gentamicin-FTA injection was necessary to obtain 1 or more signs indicating a reduction of the vestibular function in the treated ear. Four patients needed another treatment because of the persistence of their incapacitating symptoms during the follow-up. Four patients needed more than 1 injection to obtain a vestibular hypofunction. None of the patients who received 1 or 2 injections presented hearing loss in direct temporal relationship to the treatment. CONCLUSIONS: A mixture of gentamicin and fibrin glue makes it possible to considerably reduce the number of administrations in patients with intractable unilateral Menière's disease. Spontaneous nystagmus, post head shaking nystagmus, and a head thrust sign are the clinical signs that indicate onset or progression of unilateral vestibular hypofunction. These signs were obtained with only 1 injection in 81% of patients.

Large vestibular aqueduct syndrome: audiological, radiological, clinical, and genetic features.

PURPOSE: The aim of this study was to analyze the clinical, audiological, radiological, and genetic features of a group of patients affected with large vestibular aqueduct syndrome. MATERIALS AND METHODS: Seventeen patients affected with large vestibular aqueduct syndrome (LVAS), diagnosed by means of high-resolution magnetic resonance imaging of the inner ear, with 3-dimensional reconstructions of the labyrinth and by high-resolution spiral computed tomography of the temporal bone, performed only on the oldest patients, have been submitted to a complete audiological evaluation, a thyroid functional and ultrasonographic study, and a molecular study of the PDS gene. RESULTS: The clinical presentation of LVAS was very variable in our group of patients. The enlarged vestibular aqueduct was bilateral in 15 cases and unilateral in 2; it was the only malformation of the labyrinth in 12 patients, whereas it was associated with other inner ear anomalies in the other 5. The hearing loss was very variable in degree (from mild to profound), age at onset, and progression. Moreover, among the 17 patients, 10 were clinically affected by Pendred's syndrome (PS), 3 by distal renal tubular acidosis associated with large vestibular aqueduct, whereas in 3 patients the large vestibular aqueduct was not syndromal. Finally, we identified mutations in the PDS gene in 5 of 10 patients with PS. CONCLUSIONS: Our data underscore the frequent role of the large vestibular aqueduct syndrome in the pathogenesis of sensorineural hearing loss and the overall wide variability in its audiological features. It is also highlighted that LVAS is often part of some syndromal diseases, most of which are PS, which is often misdiagnosed because of the varying degree of thyroid symptoms. This study also underscores the possible role of hydro-electrolyte and acid-base endolymphatic fluid disorders in the pathogenesis of enlarged vestibular aqueduct syndrome.

3-D CT and MRI co-registration in the assessment of cochlear implantation.

BACKGROUND: The aim of this study was to evaluate the feasibility of co-registering preoperative MRI and postoperative CT and to assess the position of the electrode within the cochlea. MATERIAL/METHODS: In a series of 14 patients, high-resolution MRI datasets of the cochlea obtained before implantation and multirow CT datasets obtained after implantation were co-registered using a stereoscopic display and volume-rendering platform (Dextroscope, Volume Interactions/Bracco, Singapore). Image co-registration was performed with a semi-automatic method (multipoint plus freehand fusion). RESULTS: In 2 patients the electrode was correctly inserted in the middle turn of the cochlea and the assigned rank was 4 (corresponding to the initial tract of the middle turn). In 8 patients the rank was 3, meaning that the electrode tip reached the upper portion of the basal turn. In 4 patients the rank was 2, meaning that the electrode tip reached the middle portion of the basal turn; in two of these patients, electrode kinking was observed. CONCLUSIONS: Co-registration of preoperative MRI and postoperative CT is feasible and represents a unique method to assess electrode position within the membranous labyrinth.

Modified Bondy radical mastoidectomy: long-term personal experience.

The 'Bondy operation', or modified Bondy radical mastoidectomy, consists of a modification of the radical procedure by which the mastoid and epitympanum are exteriorized with preservation of the pars tensa and ossicular chain. In the 10-year period from 1986 to 1996, 53 patients of the ENT Department of the University of Pisa underwent a modified Bondy radical mastoidectomy, performed with a personalized procedure; 45 of them had a follow up of at least five years. After the surgical operation, the ears were free of complications in 38 cases (84.5 per cent), while in the other seven cases residual cholesteatoma (one case), tympanic retraction (four cases) or recurrent otorrhoea and phlogosis (two cases) were observed. The post-operative hearing level was unchanged or improved in 41 patients (91 per cent) (33 subjects had an unchanged gap and eight an improved gap), and only in the remaining four cases was the gap made worse. Based on our experience, the modified Bondy radical mastoidectomy is an extremely effective operation with a clear place in modern ENT surgery. When performed on carefully selected patients, it has been proven to offer good functional and anatomical results.

Far advanced otosclerosis: stapes surgery or cochlear implantation?

OBJECTIVE: Nowadays, two surgical alternatives are to be considered in patients with far advanced otosclerosis: stapedectomy and cochlear implantation. The aim of this study was to analyze and compare the hearing and communicative results obtained in two groups of patients affected with far advanced otosclerosis, who were treated with the two different surgical procedures, to assess the proper surgical approach for these patients. DESIGN: Retrospective study. SETTINGS: University hospital and referral audiologic centre. METHODS: We submitted 11 adult patients, affected by far advanced otosclerosis and exhibiting unsatisfactory communicative abilities with hearing aids, to two different procedures: 5 to cochlear implantation, and 6 to stapedotomy followed by hearing aid fitting. The benefits afforded by the two procedures were assessed by means of pure-tone audiometry and speech audiometry in an open field and by means of a speech perception test. MAIN OUTCOME MEASURES: Hearing and communicative outcomes, measured 1 year after intervention. RESULTS: The results achieved in the patients subjected to stapedotomy were unpredictable and variable: very good in some cases but unsatisfactory in others, whereas those who had cochlear implantation all achieved satisfactory results with regard to speech recognition. CONCLUSIONS: Patients who underwent cochlear implantation achieved better hearing and communicative results than those who underwent stapedotomy. Even if the number of patients reported in this study is too small to provide definitive results, and despite the reportedly better results afforded by cochlear implantation, in our opinion, correction of far advanced otosclerosis should first be attempted via stapedotomy, and cochlear implantation should instead be reserved for cases in which stapedotomy is unsuccessful or for which imaging techniques unequivocally reveal a fenestral or cochlear obstruction.

Scala vestibuli cochlear implantation in patients with partially ossified cochleas.

Partial cochlear obstruction is a relatively common finding in candidates for cochlear implants and frequently involves the inferior segment of the scala tympani in the basal turn of the cochlea. In such patients, the scala vestibuli is often patent and offers an alternative site for implantation. The current report describes two patients with such partial obstruction of the inferior segment of the basal cochlear turn, caused in one case by systemic vasculitis (Takayasu's disease) and in the other by obliterative otosclerosis. A scala vestibuli implantation allowed for complete insertion of the electrode array. No problems were encountered during the surgical procedures and the good post-operative hearing and communicative outcomes achieved were similar to those reported in patients without cochlear ossification. The importance of accurate pre-operative radiological study of the inner ear is underscored, to disclose the presence and define the features of the cochlear ossification and ultimately to properly plan the surgical approach.

Correlations between virtual endoscopy and otoendoscopy of the retrotympanum.

The aim of this study was to examine the anatomical landmarks of the retrotympanum using two different techniques, virtual endoscopy (VE) and fiberoptic endoscopy, and to correlate the results furnished by the two methods. Ten otosclerotic patients who were due to undergo stapedectomy were scanned using high-resolution spiral CT. Selected CT datasets were processed with Navigator 2.0 software to obtain virtual endoscopic views of the retrotympanum. Subsequently, during the surgical procedure, fiberoptic endoscopy was performed with 2.7-mm 0 degrees and 30 degrees rigid endoscopes. The ability of the two imaging methods to identify specific anatomical structures was then compared. In all cases the pyramidal eminence, pyramidal crest and sinus tympani were clearly identified in both VE images and otoendoscopy recordings, while fiberoptic endoscopy seemed to be less satisfactory than VE for studying the facial sinus, sinus of Proctor and fossula of Grivot. The two techniques proved to be equally sensitive for visualizing the ponticulus and subiculum, while the stapedius tendon could be visualized only by means of fiberoptic endoscopy. Overall, VE imaging appears promising for rendering important anatomical details of the retrotympanum, allowing identification of osseous landmarks and exploring recesses that are difficult to visualize via otoendoscopy.

Single photon emission computed tomography in otosclerosis: diagnostic accuracy and correlation with age, sex, and sensorineural involvement.

OBJECTIVE: To evaluate the accuracy of single photon emission computed tomography (SPECT) in detecting otospongiotic foci of the labyrinthine capsule in otosclerotic patients and to correlate the metabolic patterns detected by SPECT with age, sex, and sensorineural hearing loss. PATIENTS AND METHODS: Thirty-six patients with surgically confirmed otosclerosis and a control group of 12 subjects with normal hearing; each subject underwent SPECT study of the skull with (99m)technetium-diphosphonate ((99m)Tc-medronate). Statistical analysis of the results was performed by use of the Mann-Whitney U test. RESULTS: SPECT seemed to be very sensitive in differentiating otospongiotic bone from normal bone; in the affected group, only 2 of 72 ears yielded false-negative results (sensitivity 97.2%). Moreover, in the otosclerotic patients, the mean petrosa uptake value was higher than in the control group, a difference that was statistically significant (p < 0.0001). MAIN OUTCOME MEASURES: Regarding uptake in relation to patient age, an inverse relationship was observed between increased metabolic activity and age: the mean uptake index in the younger patients was significantly higher than that in the older patients (p < 0.0001). By contrast, no statistically significant differences were found between men and women (p = 0.1519). Comparison of SPECT alterations with bone conduction thresholds revealed a statistically significant correlation (p = 0.0002 and p = 0.0010) between increased metabolic bone activity and sensorineural involvement only in the younger group of otosclerotic patients. CONCLUSIONS: Diphosphonate bone SPECT is the only functional method that allows in vivo evaluation of disease activity, and it was highly sensitive in detecting otosclerosis. SPECT can be considered useful in the diagnosis of otosclerosis that is difficult to recognize, such as cochlear otosclerosis and far-advanced otosclerosis, and it could also find a place in evaluating the efficacy of medical therapy for otosclerosis.

Distal renal tubular acidosis associated with isolated large vestibular aqueduct and sensorineural hearing loss.

Distal renal tubular acidosis (dRTA) is characterized by a defect in urinary acidification with various degrees of metabolic acidosis; it can be inherited either as an autosomal dominant trait or as a recessive trait. The recessive form is associated in about one third of cases with progressive sensorineural hearing loss (SNHL). We performed a neuroradiological study in 3 consecutive unrelated pediatric patients affected with sporadic dRTA and progressive SNHL that disclosed an enlarged vestibular aqueduct (VA) and endolymphatic sac (ES) in each. The presence of an enlarged VA in our patients with dRTA and SNHL could contribute to the development, or at least the progression, of the hearing impairment. We suppose that the same molecular defect present in both the kidney and the inner ear could be the cause of dRTA and of the development of the enlarged VA and ES.