Botulinum toxin injection into the intrinsic laryngeal muscles to treat spasmodic dysphonia: A multicenter, placebo-controlled, randomized, double-blinded, parallel-group comparison/open-label clinical trial.

BACKGROUND AND PURPOSE: Botulinum toxin (BT) injection into the laryngeal muscles has been a standard treatment for spasmodic dysphonia (SD). However, few high-quality clinical studies have appeared, and BT is used off-label in most countries. METHODS: We performed a multicenter, placebo-controlled, randomized, double-blinded, parallel-group comparison/open-label clinical trial to obtain approval for BT (Botox) therapy in Japan. Twenty-four patients (22 with adductor SD and two with abductor SD) were enrolled. The primary end point was the change in the number of aberrant morae (phonemes) at 4 weeks after drug injection. The secondary end points included the change in the number of aberrant morae, GRBAS scale, Voice Handicap Index (VHI), and visual analog scale (VAS) over the entire study period. RESULTS: In the adductor SD group, the number of aberrant morae at 4 weeks after injection was reduced by 7.0 ± 2.30 (mean ± SE) in the BT group and 0.2 ± 0.46 in the placebo group (p = 0.0148). The improvement persisted for 12 weeks following BT injections. The strain element in GRBAS scale significantly reduced at 2 weeks after BT treatment. The VHI and VAS scores as subjective parameters also improved. In the abductor SD group, one patient responded to treatment. Adverse events included breathy hoarseness (77.3%) and aspiration when drinking (40.9%) but were mild and resolved in 4 weeks. CONCLUSIONS: Botulinum toxin injection was safe and efficacious for the treatment of SD. Based on these results, BT injection therapy was approved as an SD treatment in Japan.

Phonatory function in patients with well-differentiated thyroid carcinoma following meticulous resection of tumors adhering to the recurrent laryngeal nerve.

BACKGROUND: Well-differentiated thyroid carcinomas (WDTCs) sometimes adhere firmly to the recurrent laryngeal nerve (RLN), while allowing normal mobility of the vocal fold (VF). Meticulous dissection of the adhered tumor from the RLN is known to be effective, preserving VF mobility and oncological safety. However, phonatory function following this preservation procedure has yet to be evaluated sufficiently. The objective of this study was to examine phonatory function following the preservation procedure. METHODS: Ten patients with WDTCs, demonstrating normal preoperative VF mobility with tumors adhering to the RLN, underwent the preservation procedure between 2000 and 2013 (preservation group). During the same period, nine patients with WDTCs demonstrating normal VF mobility underwent resection and reconstruction of the tumor-invaded RLNs (reconstruction group). Phonatory function, including maximum phonation time (MPT), mean flow rate (MFR), jitter, shimmer, harmonics-to-noise ratio, and GRBAS scale score, was evaluated and compared statistically between the two groups. RESULTS: The mean values of MPT and MFR in the preservation group were at normal levels. Both G and B scores of GRBAS scale were at near-normal levels. Additionally, the mean B score of the GRBAS scale was significantly better in the preservation group than in the reconstruction group. CONCLUSIONS: When normal VF mobility is observed preoperatively, meticulous resection for preserving RLN would contribute to maintain not only normal level of MPT and MFR, but also to provide better B score of GRBAS scale than RLN resection followed by immediate reconstruction.

Effects of Chin-Down Maneuver on the Parameters of Swallowing Function After Esophagectomy With 3-Field Lymphadenectomy Examined by Videofluoroscopy.

OBJECTIVES: To determine the effect of the chin-down maneuver after esophagectomy with 3-field lymphadenectomy (3FL) on pharyngeal residue, upper esophageal sphincter (UES) opening, and laryngeal closure. DESIGN: Prospective data were collected from a pharyngeal videofluoroscopic swallowing study. SETTING: Dysphagia clinics. PARTICIPANTS: Patients selected according to the inclusion criteria (N=14; mean age, 65.9y) from a total of 43 patients who underwent esophagectomy with 3FL from May to December 2014 were enrolled. INTERVENTIONS: Videofluoroscopy was conducted in head-neutral and chin-down positions to measure the pharyngeal constriction ratio (PCR), amount of residue in the vallecula and pyriform sinus after the first swallow, UES opening diameter, duration of UES opening, and duration of laryngeal vestibule closure. MAIN OUTCOME MEASURES: The aforementioned parameters were compared statistically between the head-neutral and chin-down positions. RESULTS: In comparison with the neutral group, the PCR and residue in the pyriform sinus were significantly smaller in the chin-down group (P<.01). However, the residue in the vallecula did not differ significantly from that of the neutral group (P=.44). The UES opening diameter, duration of UES opening, and duration of laryngeal vestibule closure were all significantly larger in the chin-down group than in the neutral group (P<.05). CONCLUSIONS: This study demonstrates that use of the chin-down maneuver after esophagectomy with 3FL can help expedite swallowing by strengthening pharyngeal constriction, widening the UES, and enhancing laryngeal closure.

Videofluoroscopic evaluation of pharyngeal swallowing dysfunction after esophagectomy with three-field lymph node dissection.

To determine the factors inducing aspiration following esophagectomy with three-field lymph node dissection (3FL) and the effect of the chin-down maneuver combined with supraglottic swallow (CDSS). Retrospective analysis of a consecutive case series. Videofluoroscopic (VF) evaluations of 25 patients who consulted with our out-patient clinic from 2006 to 2012 for swallowing dysfunction following esophagectomy with 3FL without tracheostomy were reviewed. The penetration aspiration scale (PAS) was used for evaluation. The assessment parameters of VF examination were set as follows: laryngeal elevation, peristaltic wave of the pharynx, upper esophageal sphincter opening, and bolus residue in the pyriform sinus and vallecula after swallowing. Associations of the degree of aspiration with these parameters and the effect of CDSS maneuver on PAS were statistically examined. Fourteen patients had swallowing dysfunction with PAS score (1-3). Disturbance of laryngeal elevation was significantly correlated with the degree of aspiration (p = 0.021). Multivariate logistic regression analysis demonstrated that reduced laryngeal elevation significantly enhanced aspiration (p = 0.0026). Sixteen patients had already acquired compensated chin-down swallowing at the time of VF (Group I). Among the remaining nine patients (Group II), the PAS score was significantly (p < 0.05) improved after training in chin-down swallowing. The mean PAS score of the Group I patients was not significantly different from that of the Group II patients after the training in CDSS. Laryngeal aspiration following esophagectomy with 3FL is significantly correlated with reduced laryngeal elevation and can be ameliorated after training in CDSS. Level of evidence IV.

Surgical management of Eagle's syndrome: an approach to shooting craniofacial pain.

Eagle's syndrome (ES) and glossopharyngeal neuralgia (GPN) display very similar symptoms preoperatively. The objective of this study is to determine the surgical outcome of intraoral resection of the styloid process (IRSP) for ES, and to observe preoperative findings and treatment outcome of our cases presenting shooting craniofacial pain. In total, 14 symptomatic patients who presented with typical shooting craniofacial pain, had a styloid process longer than 25 mm, and underwent surgical intervention or medication alone from 2011 to 2015 were involved. They were divided into two groups: Group I included eight patients who underwent surgery following 3 months of medication failure, and Group II included six patients who received medication alone. Preoperative physical, radiographic findings and surgical outcomes were examined. In Group I patients, six cases received IRSP and five of those six cases experienced complete relief from symptoms and were confirmed as ES. Two other cases in Group I received microvascular decompression. One showed complete relief from symptoms, and was confirmed as GPN. The other case showed recurrence 1 year postoperatively, received IRSP with complete relief from symptoms, and was confirmed as ES. In Group II, three cases experienced complete relief from symptoms with 3 months of medication alone. IRSP is an effective treatment for ES. There was no clear difference in the preoperative findings for ES and GPN, suggesting the difficulty in making a preoperative differential diagnosis between the two conditions. Close cooperation between ENT and neurosurgery surgeons is needed.

Postdeglutitive residue in vagus nerve paralysis and its association with feeding style.

The objective of this study is to compare the postdeglutitive pharyngeal residues between Xth cranial nerve paralysis (XNP) and isolated recurrent laryngeal nerve paralysis (RLNP) to elucidate the association with feeding style. This study enrolled 15 XNP patients with injuries at the brainstem level (Group I) and 26 patients with RLNP (Group II). All subjects underwent videofluoroscopic swallowing studies (VFSS). The pyriform sinus (PS) and vallecula residues were quantified. The symmetry of the affected versus non-affected sides was compared in both groups. Feeding style at the time of VFSS was also examined. The intra-rater correlation coefficients for all of the data, including the areas of both the vallecula and pyriform sinus on the affected and non-affected sides, were 0.88-0.92 (p < 0.001), reflecting high consistency of the evaluation. In Group I, there was significantly (p < 0.01) more residue in the PS, but not vallecula, compared to the respective non-affected sides, while in Group II there were no significant differences in residue between the affected and non-affected sides for either the vallecula or PS. Comparing Groups I and II, there was significant (p < 0.01) residue on the affected side in the PS but not the vallecula. There was a significant correlation between dependency on a feeding tube and XNP (p < 0.01, Chi-square test). XNP at the brainstem level may cause significantly increased residue in the PS compared to RLNP. This might increase the dependency on a feeding tube with XNP.

Comparison of vocal outcome following two different procedures for immediate RLN reconstruction.

The objective of this study was to compare time-dependent improvements in phonatory function and stroboscopic findings following two different procedures for immediate reconstruction of the recurrent laryngeal nerve (RLN) during neck tumor extirpation. Seventeen patients with neck tumors, consisting of advanced thyroid cancer (n = 15), metastatic neck lymph nodes from other malignant lesions (n = 2), underwent resection of the primary lesion and involved RLN. Immediate RLN reconstruction by either: (1) ansa cervicalis nerve (ACN) to RLN anastomosis (n = 8); or (2) placement of the great auricular nerve (GAN) between the cut ends of the RLN (n = 9) was performed from 2000 to 2011. Phonatory function [maximum phonation time, mean airflow rate (MFR), jitter, and shimmer) and stroboscopic findings (regularity, amplitude, and glottal gap) were examined at 1, 6, and 12 months postoperatively. Stroboscopic findings were assessed by two otolaryngologists and one speech pathologist. There were no significant differences in any parameter for either phonatory function or stroboscopic findings between ACN and GAN with the exception of jitter and shimmer, in which ACN was superior to GAN at 1 month postoperatively. All parameters improved significantly between 1 and 12 months postoperatively for both phonatory function and stroboscopic findings (P < 0.05). Either method of immediate RLN reconstruction at the time of neck tumor extirpation (i.e., ACN or GAN) provided both excellent long-term postoperative phonatory function and stroboscopic findings, and there was little difference in vocal outcome between the two procedures.

Propagation Curve and Velocity of Swallowing Pressure in Healthy Young Adults.

The objective of this study is to construct a propagation curve and determine propagation velocities in young healthy adults examined using a 2.64-mm-diameter high-resolution manometry catheter with 36 circumferential sensors; to explore data reproducibility; and to determine whether the swallowing pressure (SP) propagation velocity correlated with bolus volume. Repeated measures with subjects serving as their own controls. Thirty healthy subjects (average age 25.3 years) swallowed saliva and 2, 5, and 10 mL of cold water to determine the maximum SP from the soft palate to the cervical esophagus. The SP propagation curve was obtained by plotting the duration to reach each SP peak. The SP propagation velocity was calculated for each region. These parameters were examined according to bolus size and gender. The intra-class correlation coefficient for estimating the SP propagation curves was >0.61 (i.e., highly consistent). The propagation velocity was maximal at the meso-hypopharynx and minimal at the UES and cervical esophagus. The SP propagation curve was very reproducible within any subject. Neither the water volume (with the exception of 2 and 5 mL) nor gender exerted any apparent effect on velocity in any region. However, the velocity was quite variable at the cervical esophagus.

Long-term vocal outcomes of refined nerve-muscle pedicle flap implantation combined with arytenoid adduction.

The objective of this study is to evaluate long-term efficacy of refined nerve-muscle pedicle (NMP) flap implantation combined with arytenoid adduction (AA) for treatment of unilateral vocal fold paralysis (UVFP). The authors retrospectively reviewed 33 patients with UVFP who received refined NMP flap implantation with AA and were followed up over a 1-year period. Evaluation of vocal fold vibration (regularity, amplitude, and glottal gap), aerodynamic analysis (maximum phonation time [MPT] and mean airflow rate [MFR]), and perceptual evaluation (Grade and Breathiness) were performed preoperatively and at five different time points (1, 3, 6, 12, and 24 months) postoperatively. All voice parameters improved significantly postoperatively. All parameters except MFR also continued to improve over the course of 24 months. In the videostroboscopic analysis, the parameter for regularity 24 months after surgery was significantly improved compared with that at 1, 3, and 6 months after surgery. There were also significant improvements in amplitude and the glottal gap 24 months after surgery in comparison with values at 3 and 6 months after surgery and 3 months after surgery, respectively. Significant improvement in aerodynamic and perceptual measurements during the follow-up period together with near-normal vocal fold vibration was achieved by delayed reinnervation with refined NMP flap implantation and AA. The combined surgical technique is effective in the treatment of severe breathy dysphonia due to UVFP. Level of evidence 4.

Mouse otocyst transuterine gene transfer restores hearing in mice with connexin 30 deletion-associated hearing loss.

Although numerous causative genes for hereditary hearing loss have been identified, there are no fundamental treatments for this condition. Herein, we describe a novel potential treatment for genetic hearing loss. Because mutations or deletions in the connexin (Cx) genes are common causes of profound congenital hearing loss in both humans and mice, we investigated whether gene supplementation therapy using the wild-type Cx gene could cure hearing loss. We first generated inner ear-specific connexin 30 (Cx30)-deficient mice via the transuterine transfer of Cx30-targeted short hairpin RNA (shRNA-Cx30) into otocysts. The inner ear-specific Cx30-deficient mice mimicked homozygous Cx30-deficient mice both histologically and physiologically. Subsequently, we cotransfected the shRNA-Cx30 and the wild-type Cx30 gene. The cotransfected mice exhibited Cx30 expression in the cochleae and displayed normal auditory functions. Next, we performed the transuterine transfer of the wild-type Cx30 gene into the otocysts of homozygous Cx30-deficient mice, thereby rescuing the lack of Cx30 expression in the cochleae and restoring auditory functioning. These results demonstrate that supplementation therapy with wild-type genes can restore postnatal auditory functioning. Moreover, this is the first report to show that Cx-related genetic hearing loss is treatable by in vivo gene therapy.

Retrospective analysis of the clinical course for intubation vs. unspecified laryngeal granulomas.

Intubation laryngeal granulomas (ILGs) are a well-known complication of endotracheal intubation. Cases other than ILGs can be categorized as unspecified laryngeal granulomas (ULGs) since their etiologies are often difficult to confirm. We intended to clarify clinical features of both ILGs and ULGs and that anticoagulant medication could cause the formation and delayed healing of ILGs in terms of wound-healing delay. We compared the results of our treatment of ILGs (n = 16) and ULGs (n = 47) treated between 1998 and 2009 to characterize these patients. The clinical course, treatment (medical vs. surgical), indications for surgical resection, treatment outcome, and use of anticoagulants for preexisting disease were reviewed and compared between these two groups. The resolution rate was significantly better in ILGs (p < .05). Five ILGs and seven ULGs were surgically resected. The main reason for resection was airway obstruction and the need for histological assessment, respectively. The use of anticoagulants was significantly higher in ILGs than ULGs (8/16 vs. 4/47, p < .01). The resolution period was significantly longer in the ILGs patients with anticoagulant medication compared to that in the ILGs patients without anticoagulant medication (152 ± 101 days vs. 76 ± 44 days, p < .05). ILGs may have different clinical course from ULGs, especially in terms of the resolution period. Moreover, administration of anticoagulants may deter healing of small injury due to intubation. Patients taking anticoagulants should be managed carefully during the perioperative period to prevent the occurrence of ILGs.

Recurrent laryngeal nerve regeneration through a silicone tube produces reinnervation without vocal fold mobility in rats.

OBJECTIVES: We established an animal model of recurrent laryngeal nerve reinnervation with persistent vocal fold immobility following recurrent laryngeal nerve injury. METHODS: In 36 rats, the left recurrent laryngeal nerve was transected and the stumps were abutted in a silicone tube with a 1-mm interspace, facilitating regeneration. The mobility of the vocal folds was examined endoscopically 5, 10, and 15 weeks later. Electromyography of the thyroarytenoid muscle was performed. Reinnervation was assessed by means of a quantitative immunohistologic evaluation with anti-neurofilament antibody in the nerve both proximal and distal to the silicone tube. The atrophy of the thyroarytenoid muscle was assessed histologically. RESULTS: We observed that all animals had a fixed left vocal fold throughout the study. The average neurofilament expression in the nerve both distal and proximal to the silicone tube, the muscle area, and the amplitude of the compound muscle action potential recorded from the thyroarytenoid muscle on the treated side increased significantly (p < 0.05) over time, demonstrating regeneration through the silicone tube. CONCLUSIONS: Recurrent laryngeal nerve regeneration through a silicone tube produced reinnervation without vocal fold mobility in rats. The efficacy of new laryngeal reinnervation treatments can be assessed with this model.

Effect of Aging on Vocal Outcomes After Laryngeal Reinnervation Combined With Arytenoid Adduction.

OBJECTIVE: To evaluate the impact of aging on vocal function following laryngeal reinnervation combined with arytenoid adduction (AA) in the treatment of paralytic dysphonia. METHODS: Sixty-eight patients with unilateral vocal fold paralysis who underwent refined nerve-muscle pedicle flap (NMP) implantation and AA were classified into four groups according to age: under 50 years (-50), in their 50s, 60s, and 70 years and older (70+). These groups consisted of 15, 14, 22, and 17 patients, respectively. Their vocal function was followed periodically for 24 months after surgery. RESULTS: Vocal function in all groups showed significant improvement after surgery. Significant improvements in vocal function were observed during a 24-month follow-up period: maximum phonation time in the -50 and 50 seconds groups; pitch range and voice handicap index-10 in the -50, 50s, and 60s groups; "Grade" in the -50, 50s, and 70+ groups; and "Breathiness" and voice-related quality of life in all groups. There were no significant differences in vocal function among the four groups, except for pitch range, at the 24-month postoperative assessment. CONCLUSIONS: Although the younger groups tended to exhibit better vocal function compared to the older groups 24 months postoperatively, the refined NMP+AA proved effective in the treatment of breathy dysphonia resulting from unilateral vocal fold paralysis, not only in the younger population but also in the older population.

Effect of Voice Therapy as a Supplement After Reinnervation Surgery for Breathy Dysphonia Due to Unilateral Vocal Fold Paralysis.

OBJECTIVE: To evaluate whether vocal function exercises (VFE) could be an adjunct treatment for patients with unilateral vocal fold paralysis (UVFP) who were not satisfied with their postoperative voices after reinnervation surgeries. STUDY DESIGN: Retrospective. METHODS: Medical records of the patients with UVFP who underwent laryngeal reinnervation between October 2011 and October 2014 were reviewed. Patients were classified into two groups: one received VFE according to patients' desire (VFE group) and the other did not have voice therapy (control group). Effects of VFE were assessed by vocal fold vibration (regularity, amplitude and glottal gap), aerodynamic measurements (maximum phonation time (MPT) and mean airflow rate (MFR)), GRBAS scale, acoustic parameters (pitch range, pitch perturbation and amplitude perturbation quotients (PPQ, APQ), and noise-to-harmonics ratio (NHR)) and subjective evaluation by patients (Voice Handicap Index-10 (VHI-10)). Phonatory function was also compared between the two groups at three time points: before reinnervation surgery, before VFE, and after VFE. RESULTS: Thirty patients were enrolled (11 men, 19 women). The VFE group included eight patients, and 22 patients served as controls. In the VFE group, several parameters (amplitude, MPT, MFR, pitch range, APQ, and NHR) did not improve significantly after surgery, while all parameters examined improved significantly in the control group. After VFE, amplitude, glottal gap, MFR, B score, pitch range, and PPQ showed significant improvement, while the control group did not show a significant improvement except in VHI-10, during the corresponding period. Significant differences in G and B scores and VHI-10 between the two groups were observed at the third time point. CONCLUSIONS: VFE may be used as an adjunct treatment for patients with UVFP who are not satisfied with their voices after reinnervation surgery. However, phonatory function after VFE may not reach the same level as for those who are satisfied with their voices after reinnervation surgery.

Identification of mild cognitive impairment subtypes predicting conversion to Alzheimer's disease using multimodal data.

Mild cognitive impairment (MCI) is a high-risk condition for conversion to Alzheimer's disease (AD) dementia. However, individuals with MCI show heterogeneous patterns of pathology and conversion to AD dementia. Thus, detailed subtyping of MCI subjects and accurate prediction of the patients in whom MCI will convert to AD dementia is critical for identifying at-risk populations and the underlying biological features. To this end, we developed a model that simultaneously subtypes MCI subjects and predicts conversion to AD and performed an analysis of the underlying biological characteristics of each subtype. In particular, a heterogeneous mixture learning (HML) method was used to build a decision tree-based model based on multimodal data, including cerebrospinal fluid (CSF) biomarker data, structural magnetic resonance imaging (MRI) data, APOE genotype data, and age at examination. The HML model showed an average F1 score of 0.721, which was comparable to the random forest method and had significantly more predictive accuracy than the CART method. The HML-generated decision tree was also used to classify-five subtypes of MCI. Each MCI subtype was characterized in terms of the degree of abnormality in CSF biomarkers, brain atrophy, and cognitive decline. The five subtypes of MCI were further categorized into three groups: one subtype with low conversion rates (similar to cognitively normal subjects); three subtypes with moderate conversion rates; and one subtype with high conversion rates (similar to AD dementia patients). The subtypes with moderate conversion rates were subsequently separated into a group with CSF biomarker abnormalities and a group with brain atrophy. The subtypes identified in this study exhibited varying MCI-to-AD conversion rates and differing biological profiles.

The prevalence and clinical features of spasmodic dysphonia: A review of epidemiological surveys conducted in Japan.

OBJECTIVES: Spasmodic dysphonia (SD) is a rare disease and its epidemiological status is unclear. This review aimed to explore the current prevalence and clinical features of SD in Japan. METHODS: We reviewed Japanese surveys of SD and compared them to surveys reported from other countries. We focused on SD prevalence, clinical features (SD type, sex and age), and treatment modalities. RESULTS: The SD prevalence in Japan was 3.5-7.0/100,000, similar to that in Rochester (NY, USA) and Iceland. Adductor SD predominated (90-95%) and females were four-fold more likely to be affected than males. Mean age at onset was approximately 30 years in Japan. Several years elapsed from onset to diagnosis. The most frequent treatment was botulinum toxin injection, and surgical intervention, particularly type 2 thyroplasty is becoming more popular. CONCLUSIONS: Our review demonstrated some differences of clinical features of SD in Japan compared with other countries, such as a greater female predominance and younger age of onset. Many physicians and patients may be unfamiliar with the clinical features of SD leading to delayed of diagnosis. Therefore, we proposed diagnostic criteria to facilitate early diagnosis and an appropriate choice of treatment modalities.

Effects of nerve-muscle pedicle on immobile rat vocal folds in the presence of partial innervation.

OBJECTIVES: We investigated whether implantation of an ansa cervicalis nerve (ACN)-muscle pedicle into the thyroarytenoid (TA) muscle is efficacious in the presence of partial recurrent laryngeal nerve (RLN) innervation. METHODS: We studied a total of 36 rats. Twelve of the rats served as positive and negative control animals. In the remaining 24 rats, the left RLN was transected, a 1-mm piece of nerve was removed, and the stumps were abutted in silicone tubes (STs), inducing partial RLN regeneration. Twelve of the ST-treated rats underwent this procedure alone, and the other 12 rats had a nerve-muscle pedicle (NMP) implanted into the left TA muscle 5 weeks after ST treatment. At 15 weeks, reinnervation was assessed by histologic evaluation of the TA muscle and by electromyography with stimulation of the RLNs and ACNs. RESULTS: The muscle area, the number of nerve terminals, the number of acetylcholine receptors, and the ratio of nerve terminals to acetylcholine receptors were significantly greater (p < 0.05) in the NMP group than in the ST group. Electromyography elicited TA muscle compound action potentials upon stimulation of the RLNs and ACNs. CONCLUSIONS: In rats, NMP implantation is efficacious for reducing atrophic changes in the TA muscle in the presence of partial RLN innervation.

Does subepithelial hemorrhage cause persistence of laryngeal granuloma?

OBJECTIVES: To determine the incidence of black spots after resolution of laryngeal granuloma (LG), to compare the disease duration from the beginning of treatment to resolution between patients with and without black spots, and to assess the histologic findings of LG in resected or biopsied specimens. STUDY DESIGN: Retrospective. METHODS: Forty-six patients with LG on the cartilaginous portion of the vocal fold were included. Their clinical records were reviewed. Histologic specimens were re-examined. RESULTS: Causes of LG were postintubation in 10 patients, unilateral vocal fold immobility in 1, Candida infection in 1, and were not specified in 34 (either hyperfunctional vocal abuse, laryngopharyngeal regurgitation, or both). Of the 10 patients with postintubation LG, 9 resolved; of the 33 patients with LG from other causes, 21 resolved. Of the 28 resolved patients, 12 developed a black spot at the previous lesion site. Of the 18 patients whose LG resolved without surgical intervention, 11 developed a black spot at the previous lesion site, and the remaining 7 patients did not develop any black spots. The treatment period until LG resolution was significantly longer among patients with a black spot than those without a spot (P = .0372). Histologic examination revealed the presence of hemosiderin accumulation accompanied by infiltration of lymphocytes and macrophages in 8 of the 16 patients who had their LGs resected or biopsied. CONCLUSIONS: Accumulation of hemosiderin in the subepithelial layer, together with little blood flow and dense connective tissue in the cartilaginous portion of the vocal fold, are important factors contributing to the persistence of LG.

Reduction surgeries for delayed cases with isolated blowout fractures.

OBJECTIVE: To show the effectiveness of endoscopic reduction surgeries for delayed cases with blowout fractures, and to determine the cause of persisting diplopia based on surgical findings. DESIGN: Retrospective study. SETTING: Between 1997 and 2006, 114 patients with isolated blowout fractures underwent surgery. In 6 of 114 patients, there were delayed cases in which over 3 months had elapsed since the initial trauma. For persisting diplopia, surgeries were performed using an endoscopic endonasal approach. RESULTS: Adhesion between the protruded periorbita and the paranasal sinus mucosa was remarkable in the delayed cases. Dissection of the adhesion and removal of the bone fragments were performed. The ocular motility improvement was confirmed by intraoperative eye traction tests. Postoperatively, diplopia disappeared in five patients. CONCLUSION: Endoscopic reduction surgeries for delayed cases are available in the treatment of blowout fractures. The main cause of diplopia was determined to be the adhesion.