Superior semicircular canal dehiscence repair with small middle fossa craniotomy using an oto-microscopic and co-endoscopic assisted approach.

OBJECTIVE: Superior semicircular canal dehiscence is an uncommon neurotological disorder in which the petrous temporal bone overlying the superior semicircular canal lacks bone. Its most common symptoms include amplification of internal sounds, autophony, tinnitus, sound- and pressure-induced vertigo, hyperacusis, oscillopsia, and hearing loss. This video presentation aimed to demonstrate endoscopic-assisted repair of superior semicircular canal dehiscence with middle fossa craniotomy. METHOD: Eleven patients with superior semicircular canal dehiscence, verified with temporal computed tomography, were enrolled in the study. RESULT: An endoscopy-assisted middle fossa approach was applied to all patients. Superior semicircular canal dehiscence was successfully repaired with an endoscope in 11 patients. CONCLUSION: Endoscopic-assisted repair of superior semicircular canal dehiscence may be a superior approach compared with binocular operative microscopy.

Midnasal stenosis in adults with normative values.

BACKGROUND: Congenital midnasal stenosis has previously been described as a cause of nasal obstruction in infants, and conservative and interventional treatments have been suggested. However, midnasal stenosis in adults has not been reported and related normative measurements have not been studied. METHODS: Three adult patients presented with nasal obstruction and, based on examination and radiological findings, were diagnosed with midnasal stenosis. Anatomical measurements were studied in axial and coronal computed tomography scans, and compared with findings for 161 healthy individuals. RESULTS: Anatomical measurements showed that the endonasal cavity was larger in males than females. The midnasal region was found to be constricted in patients compared to healthy controls. CONCLUSION: This is the first study to report on midnasal stenosis in adults and to define normative anatomical measurements in adults. In patients presenting with nasal obstruction, midnasal stenosis should be suspected during endoscopic visualisation of medially located middle turbinates and uncinate processes in nasal cavities. A definitive diagnosis of midnasal stenosis can be made by examining paranasal sinus computed tomography scans. Endoscopic middle turbinectomy, complete uncinectomy, mega maxillary antrostomy and partial anterior ethmoidectomy have been suggested to relieve midnasal stenosis.

The effect of coronavirus disease 2019 on the hearing system.

OBJECTIVE: This study aimed to evaluate different auditory regions with audiological tests, based on the presumption that there may be damage to the structures in the hearing system after coronavirus disease 2019. METHODS: Twenty individuals with no history of coronavirus disease 2019 and 27 individuals diagnosed with coronavirus disease 2019 were compared. Pure tone, speech and extended high-frequency audiometry, acoustic immitansmetry, transient evoked and distortion product otoacoustic emissions testing, and auditory brainstem response testing were conducted. RESULTS: The pure tone audiometry and extended high-frequency mean threshold values were higher in the coronavirus disease 2019 group. The transient evoked otoacoustic emissions signal-to-noise ratios were bilaterally lower at 4 kHz in individuals with a coronavirus disease 2019 history. In the auditory brainstem response test, only the interpeak latencies of waves III-V were significantly different between groups. CONCLUSION: Coronavirus disease 2019 may cause damage to the hearing system. Patients should be followed up in the long term with advanced audiological evaluation methods in order to determine the extent and level of damage.

Effects of Nd-YAG Laser iridotomy on anterior segment measurements in pigment dispersion syndrome and ocular hypertension.

PURPOSE: To compare the anterior segment optical coherence tomography (AS-OCT) measurements of eyes with pigment dispersion syndrome (PDS) and ocular hypertension (OHT) before and after neodymium:yttrium-aluminum-garnet (Nd:YAG) laser peripheral iridotomy (LPI). METHODS: A total of 23 eyes of 23 patients with PDS and OHT with features of PDS were included in this retrospective study. All of the eyes with PDS and OHT were examined by AS-OCT before and after Nd:YAG LPI. Anterior chamber depth, angle opening distance 500, angle opening distance 750, trabecular iris space 500, trabecular iris space 750 and scleral spur angle, iris bowing and iris shape were measured with AS-OCT by the same examiner. RESULTS: The differences in all parameters before and after Nd:YAG LPI were statistically significant. Iris configuration was concave in all eyes prior to iridotomy. After Nd:YAG laser iridotomy, the iris configuration became convex in 7 eyes, flat in 9 eyes and remained concave in 7 eyes. CONCLUSION: Nd:YAG laser peripheral iridotomy is an effective method for reversing the iris concavity and iris bowing in pigment dispersion syndrome.

A comparative evaluation of segmental analysis of macular layers in patients with early glaucoma, ocular hypertension, and healthy eyes.

PURPOSE: To compare macular layer thicknesses between early glaucoma, ocular hypertension, and healthy eyes and to evaluate the accuracy of spectralis optical coherence tomography (OCT) segmentation software in discriminating early glaucoma from ocular hypertension and healthy eyes. METHODS: OCT scans were performed using the standard macular and peripapillary retinal nerve fiber layer (pRNFL) protocols on the Spectralis-OCT. The following macular thickness parameters were compared in the inner and outer circles of the Early Treatment Diabetic Retinopathy Study: total macular thickness (MT), retinal nerve fiber layer (mRNFL), ganglion cell layer (mGCL), inner plexiform layer (mIPL), inner nuclear layer (mINL), outer plexiform layer (mOPL), outer nuclear layer (mONL) and ganglion cell complex (mGCC: sum of mRNFL, mGCL, and mIPL). Sectors and layers with the best area under the receiver operating characteristic curve (AUC) were determined and compared between groups. RESULTS: Of a total of 200 eyes included in this study, 64 eyes had primary open angle glaucoma, 69 had ocular hypertension, and 67 were healthy. Peripapillary RNFL was significantly thinner in the early glaucoma group (P<0.05). For the macular variables, there was a significant reduction in the MT, mGCC, mRNFL, mGCL, and mIPL thicknesses in the early glaucoma group; while there were no statistically significant differences between the ocular hypertension and control groups (P>0.05). For distinguishing early glaucoma from normal eyes, AUCs for mGCC, mGCL, and mRNFL were similar to the pRNFL; and for early glaucoma and ocular hypertension, AUCs for mGCC, mGCL mRNF and mIPL were comparable to the pRNFL. CONCLUSION: Macular segmentation can assist in the early diagnosis of glaucoma as a complementary study to pRNFL analysis.

Analysis of retinal microvasculature in Fuchs' uveitis syndrome. Retinal microvasculature in Fuchs' uveitis.

PURPOSE: The objective of this study is to quantitatively analyse the foveal microvasculature in eyes with Fuchs' Uveitic Syndrome (FUS), or Fuchs' Heterochromic Iridocyclitis (FHI), by Optical coherence tomography angiography (OCTA). METHODS: Thirty patients with FUS and 30 healthy volunteer patients (control group) were enrolled in the study. Vascular density (VD) in the superior and deep capillary plexuses (SCP, DCP) were reported and compared between eyes with FUS (FU), fellow eyes (FE) and the control group. RESULTS: Foveal VD and parafoveal VDs in all quadrants of the SCP were significantly lower in the FU group than the FE group and normal eyes (P<0.05). Foveal VDs in the DCP were similar between the three groups (P>0.05); however, parafoveal VDs in all quadrants of the DCP were significantly lower in the FU group than in the FE and control eyes (P<0.05). Foveal and parafoveal VDs in both the SCP and DCP were similar between fellow eyes and the control group. CONCLUSION: Fuchs' Uveitic Syndrome (Fuchs' Heterochromic Iridocyclitis) affects not only the anterior uvea and vitreous but also the retinal microvasculature. Analysis by OCT-A may enable us to understand the extent of this disease.

The effect of pretreatment submucosal injections of tramadol and dexamethasone on post-endodontic pain in mandibular molar teeth with symptomatic irreversible pulpitis: a randomized controlled clinical trial.

AIM: To establish the effects of submucosal single doses of two medicines on postoperative pain after root canal treatment in mandibular molar teeth with symptomatic irreversible pulpitis. METHODOLOGY: In this randomized controlled, double-blind clinical trial, 90 patients with the diagnosis of symptomatic irreversible pulpitis in their mandibular first or second molars were included and randomly divided into three groups (n = 30): a control group that received normal saline and two experimental groups that received a single dose of either tramadol (100 mg 2 mL-1 ) or dexamethasone (8 mg 2 mL-1 ). After local anaesthesia and before treatment, submucosal injections were administered into the mucobuccal fold adjacent to the mandibular molars, and a routine single-visit root canal treatment procedure was performed in all groups. After the root canal treatments, the patients were asked to score their pain level using the Heft-Parker visual analogue scale (0-170 mm) at 6, 12, 24, 48 and 72 h. The experimental groups were compared using one-way anova or Kruskal-Wallis H-test. The groups that were significantly different were compared pairwise using Student's t-test or the Mann-Whitney U-test. The findings were expressed as the mean ± standard deviation or median (min-max). The categorical variables were tested using the chi-square test or Fisher's exact chi-square test, and the results were expressed as counts and percentages. RESULTS: At the 6-h and 48-h time intervals, the intensity of pain was significantly less in both the dexamethasone and tramadol groups than in the control group (P < 0.0167). At the end of 12 h, the pain level in the dexamethasone group was significantly less compared to the other groups (P < 0.0167). CONCLUSIONS: Pretreatment submucosal dexamethasone and tramadol injections significantly diminished post-treatment endodontic pain of patients with symptomatic irreversible pulpitis following single-visit root canal treatment. However, dexamethasone was more effective than tramadol in pain reduction in the first 12 h.

Overexpression of miR-21 Is Associated With Recurrence in Patients With Hepatitis B Virus-Mediated Hepatocellular Carcinoma Undergoing Liver Transplantation.

Liver transplantation (LT) is the best treatment option for hepatitis B virus (HBV)-mediated hepatocellular carcinoma (HCC). Nevertheless, recurrence is the most important issue after LT. The aims of the present study were to evaluate the relation of dysregulated expression of microRNAs (miRNAs) in recurrence formation in HBV-mediated HCC cases. A total of 42 HBV-mediated HCC patients were evaluated in this study. Among 21 miRNAs, the expression level of miR-106a and miR-21 were higher and miR-143 and miR145 were lower in patients with HCC compared with noncancerous liver tissues (P = .0388, P = .0214, P = .0321, and P = .002, respectively). Compared with nonrecurrent patients, the expression level of miR-21 was 3.54-fold higher and miR-145 was 2.42-fold lower in patients with recurrence during the 5-year follow-up (P = .004 and P = .032; respectively). In addition, according to multivariate Cox regression analysis, the overexpression of miR-21 was found to be a prognostic indicator in HBV-mediated HCC patients (P = .002). In conclusion, we show a significant association between high expression of miR-21 and recurrence in HBV-mediated HCC. Therefore, up-regulation of miR-21 could serve as a promising prognostic marker for HCC.

Tetanus in adults: results of the multicenter ID-IRI study.

Tetanus is an acute, severe infection caused by a neurotoxin secreting bacterium. Various prognostic factors affecting mortality in tetanus patients have been described in the literature. In this study, we aimed to analyze the factors affecting mortality in hospitalized tetanus patients in a large case series. This retrospective multicenter study pooled data of tetanus patients from 25 medical centers. The hospitals participating in this study were the collaborating centers of the Infectious Diseases International Research Initiative (ID-IRI). Only adult patients over the age of 15 years with tetanus were included. The diagnosis of tetanus was made by the clinicians at the participant centers. Izmir Bozyaka Education and Research Hospital's Review Board approved the study. Prognostic factors were analyzed by using the multivariate regression analysis method. In this study, 117 adult patients with tetanus were included. Of these, 79 (67.5%) patients survived and 38 (32.5%) patients died. Most of the deaths were observed in patients >60 years of age (60.5%). Generalized type of tetanus, presence of pain at the wound area, presence of generalized spasms, leukocytosis, high alanine aminotransferase (ALT) and C-reactive protein (CRP) values on admission, and the use of equine immunoglobulins in the treatment were found to be statistically associated with mortality (p < 0.05 for all). Here, we describe the prognostic factors for mortality in tetanus. Immunization seems to be the most critical point, considering the advanced age of our patients. A combination of laboratory and clinical parameters indicates mortality. Moreover, human immunoglobulins should be preferred over equine sera to increase survival.

Association of accessory sphenoid septa with variations in neighbouring structures.

OBJECTIVE: This study aimed to examine the relationship of the accessory sphenoidal septum with surrounding vital structures and their variations. METHODS: This cross-sectional retrospective study investigated the prevalence of accessory sphenoidal septa and their relationship with variations in surrounding vital structures in coronal and axial paranasal computed tomography images. RESULTS: Coronal and axial computed tomography images of 347 patients were assessed to evaluate the presence of accessory sphenoidal septa. Accessory sphenoidal septa originated from the internal carotid artery in 47.7 per cent of patients and from the optic nerve in 17.5 per cent. These structures were significantly associated with protrusion of the optic nerve, internal carotid canal or Vidian nerve canal. CONCLUSION: Accessory sphenoidal septa can originate from the internal carotid artery or the optic nerve. Therefore, the presence of an accessory sphenoidal septum indicates an increased risk of surgical complications including internal carotid artery injury and loss of vision due to optic nerve injury.

Hyperbaric oxygen therapy of olfactory dysfunction in diabetic neuropathy with type 2 diabetes mellitus and a new definition Diabetic Olfactopathy.

BACKGROUND: Hyperbaric Oxygen therapy is recommended as an adjuvant therapy for diabetic neuropathy. To investigate olfactory dysfunction and show the effectiveness of hyperbaric oxygen treatment in patients with type 2 diabetic neuropathy. MATERIAL AND METHODS: Patients diagnosed with Type 2 DM and diabetic neuropathy were included in the group 1. Patients of Group 1 were administered with a hyperbaric oxygen therapy for 30 sessions and patients who returned for a check up following 30 sessions were incorporated into the Group 2. Healthy volunteers with no medical problems were included in the study as a control group (Group 3). Connecticut Chemosensory Clinical Research (CCCRC) test and the subjective visual analog scale (VAS; 0-100) were utilized to evaluate the olfactory function. RESULTS: There was a statistically significant difference both between the control group and the patient group as well as before and after the HBO therapy in terms of total CCCRC scoring averages and VAS Scoring averages. CONCLUSION: When compared to normal individuals, type 2 diabetic neuropathy can cause an olfactory dysfunction, and a statistically significant improvement in olfaction can be obtained with HBO therapy. This is the first study demonstrating that the HBO therapy can play a role in treating olfactory dysfunctions suffered by the patients with diabetic olfactory neuropathies.

Auditory Pathway Features Determined by DTI in Subjects with Unilateral Acoustic Neuroma.

PURPOSE: In the studies concerning the pathology of the auditory pathway in the vestibulocochlear system, few use advanced neuroimaging applications of magnetic resonance imaging (MRI) such as diffusion tensor imaging (DTI). Those who did use reported DTI changes only at the lateral lemniscus and inferior colliculus level. The aim of our study was to determine diffusion changes in the bilateral auditory pathways of subjects with unilateral acoustic neuroma (AN) and compare them with healthy controls. MATERIAL AND METHODS: A total of 15 subjects with unilateral AN along with 11 controls underwent routine MRI and DTI. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values obtained from the lateral lemniscus, inferior colliculus, corpus geniculatum mediale, and Heschl's gyrus of the auditory pathway were then compared. RESULTS: The subjects' ADC values measured from the contralateral side were significantly higher at the lateral lemniscus, inferior colliculus, and corpus geniculatum mediale compared with those of the controls. Also, decreased FA values were noted at the inferior colliculus for both the contralateral and ipsilateral sides. The highest ADC values were detected in the inferior colliculus of the auditory pathway. CONCLUSIONS: In the auditory pathway of subjects with AN, the contralateral side is more affected than the ipsilateral side, the most affected region being the inferior colliculus. DTI is an advanced neuroimaging technique that can be used to determine the presence of microstructural damage to the auditory pathway in subjects with AN, whereas conventional MRI is not sensitive enough to detect damage.

Effects of azelastine nasal spray on nasal and nasopharyngeal microflora.

OBJECTIVE: Azelastine nasal spray is a topical antihistaminic drug for the symptomatic treatment of allergic rhinitis. This study aimed to investigate the effects of azelastine on nasal and nasopharyngeal microflora. METHODS: Swab samples from 25 patients prescribed azelastine nasal spray monotherapy were collected just before treatment and after 1 month of treatment. After incubation of inoculates, the number of bacteria present in cultures was measured (in colony-forming units per millilitre). RESULTS: Evaluation of the number of microflora revealed increased bacterial reproduction after treatment, but this difference was not statistically significant. The use of azelastine nasal spray decreased the reproduction of three potentially pathogenic bacteria; however, it did not affect the reproduction of other potentially pathogenic bacteria. CONCLUSION: The use of azelastine nasal spray for one month did not have a statistically significant effect on the numbers of nasal and nasopharyngeal microflora; it is therefore safe from a microbiological viewpoint.

Thymoquinone treatment for inner-ear acoustic trauma in rats.

OBJECTIVE: To investigate whether thymoquinone has any eliminative effects against inner-ear damage caused by acoustic trauma. METHODS: Thirty-two male rats were divided into four groups. Group 1 was only exposed to acoustic trauma. Group 2 was given thymoquinone 24 hours before acoustic trauma and continued to receive it for 10 days after the trauma. Group 3 was only treated with thymoquinone, for 10 days. Group 4, the control group, suffered no trauma and received saline instead of thymoquinone. Groups 1 and 2 were exposed to acoustic trauma using 105 dB SPL white noise for 4 hours. RESULTS: There was a significant decrease in distortion product otoacoustic emission values and an increase in auditory brainstem response thresholds in group 1 on days 1, 5 and 10, compared with baseline measurements. In group 2, a decrease in distortion product otoacoustic emission values and an increase in auditory brainstem response threshold were observed on day 1 after acoustic trauma, but measurements were comparable to baseline values on days 5 and 10. In group 3, thymoquinone had no detrimental effects on hearing. Similarly, the control group showed stable results. CONCLUSION: Thymoquinone was demonstrated to be a reparative rather than preventive treatment that could be used to relieve acoustic trauma.

Investigation of the role of major respiratory viruses in the aetiology of nasal polyps using polymerase chain reaction technique.

Objective: We aimed to identify the role of major respiratory viruses in the aetiology of human nasal polyps using polymerase chain reaction technique. Methods: Thirty patients with nasal polyps and a group of 20 healthy patients (control group) were included in this study. Mucosa was obtained from the polyps of patients with nasal polyposis and from the middle turbinate of the control group patients by means of biopsy. The samples were stored at -80 °C until molecular analysis by polymerase chain reaction was carried out. Results: In the control group, the human coronavirus and human rhinovirus were diagnosed in one of the patients and the human respiratory syncytial virus in another. In the group with nasal polyposis, the influenza B virus was identified in one of the patients and the human coronavirus in another. Conclusion: The results did not demonstrate a statistically significant relationship between nasal polyposis and respiratory viruses.

The seroprevalance of Crimean-Congo haemorrhagic fever in people living in the same environment with Crimean-Congo haemorrhagic fever patients in an endemic region in Turkey.

Crimean-Congo haemorrhagic fever (CCHF) is endemic in Turkey, and since 2004 many cases have been reported from different regions of Turkey. There are limited data about the seroprevalence of the disease in household members of patients or persons sharing the same environment. We evaluated seroprevalence of CCHF in the immediate neighbourhood and in household members of patients living in the same environment as confirmed cases of CCHF in an endemic area of Turkey. A total of 625 healthy subjects [mean (s.d.) age: 42·3 (18·4) years, 58·7% females] without a past history of CCHF infection included in this case-control, retrospective study were evaluated in terms of sociodemographic characteristics, risk factors for CCHF via a study questionnaire, while serum analysis for CCHF virus (CCHFV) IgG antibodies was performed by ELISA. Anti-CCHFV IgG antibodies were positive in 85 (13·6%) participants. None of the seropositive individuals had a history of symptomatic infection. Regression analysis revealed that animal husbandry [odds ratio (OR) 1·84, 95% confidence interval (CI) 1·09-3·11], contact with animals (OR 2·31, 95% CI 1·08-5·10), contact with ticks (OR 3·45, 95% CI 1·87-6·46), removing ticks from animals by hand (OR 2·48, 95% CI 1·48-4·18) and living in a rural area (OR 4·05, 95% CI 1·65-10·56) were associated with increased odds of having IgG seropositivity, while being a household member of a patient with prior CCHF infection had no influence on seropositivity rates. This result also supports the idea that CCHF is not transmitted person-to-person by the airborne route.

Bronchoscopy as an indicator of tracheobronchial fungal infection in non-neutropenic intensive-care unit patients.

We aimed to establish that a bronchoscopic view can be as reliable as microbiology, and support an empirical tracheobronchial fungal infection (TBFI) treatment decision. We retrospectively studied 95 respiratory failure patients with suspected TBFI admitted to the intensive-care unit (ICU) in 2008 with sticky secretions, hyperaemic mucosa, and whitish plaques on bronchoscopic view. Patients not suspected of having TBFI were chosen as a control group (n = 151). Broncheoalveolar lavage (BAL) fluid was cultured, and biopsy samples were taken from the lesions. Biopsy samples positive for fungi were defined as 'proven', only BAL-positive (+ fungi) cases were 'probable TBFI', and BAL-negative (- fungi) cases were 'possible TBFI'. BAL (+ fungi) and BAL (- fungi) in the control group were defined as 'colonization' and 'no TBFI', respectively. The sensitivity, specificity and positive and negative predictive values of BAL (+ fungi) were 85.1% (63/74), 81.4% (140/172), 66.3% (63/95), and 92.7% (140/151), respectively. Biopsies were performed in 78 of 95 patients, and 28 were proven TBFI with fungal elements, and 100% were BAL (+ fungi). Probable TBFI was seen in 30 of 95 patients with BAL (+ fungi), and possible TBFI (BAL(- fungi)) in 25 of 95. Among the 95 patients, microbiology revealed fungi (90.5% Candida species; 9.5% Aspergillus) in 63 (66.3%). In the controls, the colonization and no TBFI rates were 11 of 151 and 140 of 151, respectively. Observing sticky secretions, hyperaemic mucosa and whitish plaques by bronchoscopy is faster than and may be as reliable as microbiology for diagnosing TBFI. These findings are relevant for empirical antifungal therapy in suspected TBFI patients in the ICU.

Self-gripping Covidien™ ProGrip™ mesh versus polypropylene mesh in open inguinal hernia repair: multicenter short term results.

The purpose of this study was to compare clinical outcomes following sutureless ProGrip™ mesh repair to traditional Lichtenstein repair with polypropylene mesh secured with sutures. Data were collected prospectively and were analyzed for 57 male and 3 female patients with 60 inguinal hernias. All patients included underwent open surgical repair for inguinal hernia with polypropylene mesh or ProGrip mesh. In our two centres study sixty patients were operated; 30 were treated with Lichtenstein repair with polypropylene mesh (L group) and 30 with ProGrip mesh (P group) with or without fixation. The primary parameter measured was intensity of postoperative pain using visual analogue scale (VAS); other outcomes included assessment of early and late complication. VAS was assessed in 7 days and 4 months of the postoperative period. Our results show that VAS scored at the 7th postoperative day was 1.5 for the ProGrip mesh versus 4.4 in Lichtenstein repair group. The difference between groups was statistically significant (P=0.001). Surgery duration was significantly shorter in the P group (24.9 vs. 58.3 min; P=0.001). No recurrence was observed at 3 months in both groups. The 3-months follow-up has shown that time necessary to return to daily routine activity was significantly lower in the P group during the (P=0.001). Surgery duration, early and late postoperative, pain and return to daily routine activity rates were significantly reduced with self-gripping ProGrip mesh compared to Lichtenstein repair with polypropylene mesh.

Castleman's disease presenting as a pleural mass in the thoracic cavity.

A 61-year-old non-smoking Turkish woman presented with chest pain for 10 months. Computed tomography of the chest revealed a solitary, relatively well circumscribed, heterogeneous mass of 4 x 6 cm diameter in left posterior-lateral hemithorax. On thoracotomy, an extraparanchymal mass destructing the ribs was determined. Mass excision and partial chest wall resection were performed. On histopathologic examination, this mass showed features of the hyaline vascular type of Castleman's disease.

Structural characteristics of septal cartilage and mucoperichondrium.

AIM: During nasal septum surgery, elevation of mucoperichondrium from the anterior nasal septum may be more difficult than from the medial and posterior septum. This study aimed to evaluate any histological structural differences between the anterior and posterior nasal septum cartilage, mucoperichondrium and intervening tissue. MATERIAL AND METHOD: Unilateral mucoperichondrial flap elevation without infiltration was performed, after nasal tip and dorsum decortication, in four patients undergoing open septorhinoplasty. Full-thickness samples, including cartilage and mucoperichondrium, were removed from the anterior and posterior nasal septum and examined under light and electron microscopy. RESULTS: Light microscopy showed no difference between anterior and posterior septum specimens regarding perichondrial thickness and subperichondrial cell density. Demarcation between cartilage and perichondrium and between perichondrium and lamina propria was more regular in the posterior versus the anterior septum. Electron microscopy showed no difference in chondroblast activity at the two sites. CONCLUSION: The observed tissue demarcation irregularities may explain the greater reported difficulty in elevating anterior versus posterior nasal septum mucoperichondrium. Immunohistochemical examination would further elucidate these interstructural connections.