Palatal Movements Research Articles

Biomechanical effects of anew crimpable gate spring combined with conventional rectangular archwires for torque adjustment of individual anterior teeth : Acomparative finite element study.

Precise root torque adjustment of anterior teeth is indispensable for optimizing dental esthetics and occlusal stability in orthodontics. The efficiency of traditional rectangular archwire manipulation within bracket slots seems to be limited. The crimpable gate spring, anovel device, has emerged as apromising alternative. Yet, there is apaucity of guidelines for its optimal clinical application. This study used finite element analysis (FEA) to investigate the biomechanical impact of the gate spring on torque adjustment of individual anterior teeth and to elucidate the most effective application strategy. AFEA model was constructed by amaxillary central incisor affixed with an edgewise bracket featuring a0.022 × 0.028 inch (in) slot. Arange of stainless steel rectangular archwires, in conjunction with agate spring, were modeled and simulated within the bracket slots. Acontrol group utilized aconventional rectangular wire devoid of agate spring. Palatal root moments were standardized to 9, 18, and 36 Nmm for both experimental and control groups. The gate spring significantly amplified palatal root movement, notably with the 0.019 × 0.025 in archwire. However, this was accompanied by an increase in stress on the tooth and periodontal ligament, particularly in the cervical regions. The synergistic use of a0.019 × 0.025 in rectangular archwire with agate spring in a0.022 × 0.028 in bracket slot was identified as most efficacious for torque control of individual anterior teeth. The gate spring is aviable auxiliary device for enhancing torque adjustment on individual teeth. However, caution is advised as excessive initial stress may concentrate in the cervical and apical regions of the periodontal ligament and tooth.

Do tight nosebands have an effect on the upper airways of horses?

The public perception relating to the welfare of horses involved with equestrian sports is associated with training methods used and the presentation of horses at events. In this context, very tight nosebands, which are intended to prevent the horse from opening its mouth, also attract a lot of attention. Various studies have evaluated the impact of tight nosebands on stress parameters, whereas the effect of tight nosebands on upper airway function is unknown. Therefore, the aim of the study was to use overground endoscopy to evaluate changes in pharyngeal and laryngeal function when a tight noseband is fitted. Moreover, the ridden horse pain ethogram (RHpE) was applied to investigate signs of discomfort (Dyson et al., 2018). A randomized, blinded, and prospective study was performed. Sixteen warmblood horses consisting of twelve mares and four geldings with a mean age of 11.63 ± 3.53 years were ridden on 2 consecutive days with either loose or tight nosebands (two fingers or no space between bridge of the nose and noseband, respectively) and inserted endoscope in a random order. Videos were taken in a riding arena during a standardized exercise protocol involving beginner level tasks for 30 min in all gaits. For video analysis, freeze frames were prepared and analyzed at the beginning of the expiration phase. Pharyngeal diameter was measured using the pharynx-epiglottis ratio. Other findings (swallowing, pharyngeal collapse, soft palate movements, and secretion) were also evaluated. Moreover, the RHpE was applied. Descriptive statistics and generalized linear mixed effects models were used. Results with a p-value < 0.05 were considered statistically significant. While the pharynx-epiglottis ratio did not change significantly in horses ridden with loose versus tight nosebands, there was an increase in mean grade and total counts of parameters assessed in the pharyngeal region, for example, grade of secretion (1.5 [±SD 0.89] vs. 3.13 [±SD 0.96]; p = 0.0001), axial deviation of the aryepiglottic folds (0.29 [±SD 0.73] vs. 1.33 [±SD 1.44]; p = 0.01), and pharyngeal collapse (0.69 [±SD 0.87] vs. 1.88 [±SD 1.54]; p = 0.005) in horses ridden with tight nosebands. There was no RHpE score above 8 indicating musculoskeletal pain, but the RHpE scores were significantly higher in horses ridden with tight nosebands (p < 0.001). Video quality was limited when horses showed large amounts of secretion. Another limitation was the small number of horses. Results add to the evidence obtained in other studies that tight nosebands do not only cause adverse reactions based on the RHpE score such as head behind the vertical or intense staring but also contribute to changes in the pharyngeal region, such as increased secretion and collapse of pharyngeal structures. This may provide further support for future decisions regarding regulations on nosebands.

Клінічний випадок пізньої корекції щілини твердого піднебіння в 11-річного хлопця з двобічною розщілиною губи і піднебіння

Clefts of the lip and palate remain one of the most common congenital malformations. Bilateral cleft is considered the most complex form of the defect. There is no consensus on the timing and method of surgical treatment. However, most publications focus on the two-stage method of defect closure and recommend complete correction by 24 months of age. This clinical case deviates from the commonly accepted approach to treating children with bilateral clefts of the lip and palate. The patient sought medical help at a late age, specifically at 11 years old, due to a number of subjective and objective reasons. The aim - based on a clinical case, analyze the timely and qualitative provision of medical care, the difference in the quality of life before and after surgical intervention in patients with the described pathology. The first stage was performed at the age of 2 years. After preoperative preparation, including antibiotic therapy guided by throat swabs, the patient underwent a series of surgical procedures, including complete dissection of soft palate muscles, intravelar veloplasty, formation of a Vomer flap, and meticulous closure of the palate defect layer by layer. One month after the surgery, the patient exhibited soft palate movements (which were absent before surgery), improved feeding, and continued speech therapy sessions, resulting in significantly improved pronunciation. Analysis of this clinical case will contribute to a better understanding of the approach to treating children with bilateral clefts of the lip and palate. Timely referral of patients for comprehensive treatment, including surgical correction, subsequent orthodontic treatment, speech therapy sessions, possible psychological rehabilitation, and so on, is crucial in children with bilateral clefts of the lip and palate. The research was carried out in accordance with the principles of the Helsinki Declaration. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

State-Dependent Biomechanical Behavior of Oropharyngeal Structures in Apneic and Control Subjects: A Proof-of-Concept Study.

Rationale: Apneic individuals have reduced airway caliber during sleep. The biomechanical changes in upper airway anatomy contributing to this airway narrowing are largely unknown. Objectives: We sought to investigate the state-dependent (wake vs. sleep) biomechanical behavior of the upper airway soft-tissue and craniofacial structures. Methods: Upper airway magnetic resonance imaging was performed in 15 sleep-deprived control subjects (apnea-hypopnea index, <5; 0.3 ± 0.5 events per hour) and 12 sleep-deprived apneic subjects (apnea-hypopnea index, ⩾5; 35.2 ± 18.1 events per hour) during wake and sleep and analyzed for airway measures and soft-tissue/mandibular movement. Results: In the retropalatal region, control subjects showed sleep-dependent reductions (P ⩽ 0.037) in average cross-sectional airway area (CSA), minimum CSA, and anteroposterior and lateral dimensions. Apneic subjects showed sleep-dependent reductions (P ⩽ 0.002) in average CSA, minimum CSA, and anteroposterior and lateral dimensions. In the retroglossal region, control subjects had no sleep-dependent airway reductions. However, apneic subjects had sleep-dependent reductions in minimal CSA (P = 0.001) and lateral dimensions (P = 0.014). Control subjects only showed sleep-dependent posterior movement of the anterior-inferior tongue octant (P = 0.039), whereas apneic subjects showed posterior movement of the soft palate (P = 0.006) and all tongue octants (P ⩽ 0.012). Sleep-dependent medial movement of the lateral walls was seen at the retropalatal minimum level (P = 0.013) in control subjects and at the retropalatal and retroglossal minimum levels (P ⩽ 0.017) in apneic subjects. There was posterior movement of the mandible in apneic subjects (P ⩽ 0.017). Conclusions: During sleep, control and apneic subjects showed reductions in retropalatal airway caliber, but only the apneic subjects showed retroglossal airway narrowing. Reductions in anteroposterior and lateral airway dimensions were primarily due to posterior soft palate, tongue and mandibular movement and to medial lateral wall movement. These data provide important initial insights into obstructive sleep apnea pathogenesis.

Comparison of labio-palatal incisor movement between two wear protocols: a retrospective cohort study.

To investigate the accuracy of the Invisalign appliance in achieving predicted angular tooth movement of the maxillary central incisors, to locate the center of rotation in a labio-palatal direction, and to investigate any difference between 1-weekly and 2-weekly wear protocols. This study involved a retrospective sample of two groups of 46 Class I adult subjects treated non-extraction with different protocols of 1-weekly and 2-weekly wear. The pretreatment, predicted outcome and achieved outcome digital models were superimposed and measured using metrology software. Angular and center-of-rotation measurements in the sagittal plane for the maxillary right central incisor were analyzed. There was a statistically significant difference between predicted and achieved angular measurements (P < .005) for labial tooth movements regardless of wear protocol. For palatal movements, no statistically significant difference was observed (P > .05). A small amount of overexpression was observed in some cases. Regarding crown and root control, uncontrolled tipping was the most predictable. No statistically significant difference was found between predicted and achieved center of rotation, but the confidence interval was wide. No statistically significant difference (P > .05) was found between the two wear protocols for the parameters measured. For maxillary central incisors, labial angular movements were not as accurate as palatal movements. Overcorrection could be recommended with careful clinical monitoring due to the possibility of overexpression. Control of root movements may be unpredictable, and further research is required to draw stronger conclusions. For the parameters measured in this clinical sample, there was no difference between the two wear protocols.

Four New Cases of Progressive Ataxia and Palatal Tremor (PAPT) and a Literature Review

PAPT syndrome is a rare neurologic disorder characterized by progressive ataxia and palatal tremor (rhythmic movements of the soft palate). The first large study of PAPT patients was published in 2004, included a total of 28 sporadic PAPT cases, and suggested a neurodegenerative origin. In the last several years, case reports and small case series followed, underlining the heterogeneity of the clinical picture and underlying aetiology (including neurodegenerative, vascular, infectious/autoimmune, and genetic). As a contribution to the literature, we report on four new patients with PAPT syndrome from Bern. Our study highlights the diverse clinical presentation (pyramidal, extrapyramidal, bulbar, cognitive, psychiatric symptoms, and autonomic features), summarizes the known literature, and extends it by findings on sleep studies (obstructive/central sleep apnoea, sleep disturbance). Possible aetiologies and management aspects are discussed in light of the current literature.

Evaluation of different models of intrusive force application and temporary anchorage device (TAD) placement in total arch intrusion using clear aligners; a finite element analysis

IntroductionPresent study aims to evaluate different models of total arch intrusion using clear aligners in a finite element setup, which might be helpful in gummy smile patients who seek this treatment modality.MethodsFour patterns of intrusive forces were applied on each side of the upper arch aligner model: (1) Distal to the lateral incisors (facial − 80 g) and distal to the first molar (palatal − 150 g). (2) Distal to the lateral incisors (facial − 80 g) and distal to the first molars (facial − 80 g and palatal − 80 g). (3) Distal to the canines (facial − 80 g) and distal to the first molars (facial − 150 g). (4) Distal to the lateral incisors (facial − 80 g) and mesial to the first molars (facial − 150 g). Vertical and horizontal movements of the teeth were measured.ResultsExtrusion movements were solely detected at buccal cusps of the first and second molars in the first model. Palatal movements of posterior teeth were detected in this model. Model II showed a homogeneous intrusion in anterior and posterior teeth and the amount of palatal movements of posterior teeth was reduced compared to model I. In contrast to Model IV, Model III had more intrusion in the posterior compared to anterior teeth. Facial movements of posterior teeth were detected in the third and fourth models. Incisor teeth showed facial movements among all of the models except for the lateral incisor in the third model.ConclusionsEach model of force application, causes different outcomes and side effects which is beneficial in certain clinical situations.

Three-dimensional finite element study on the effects of maxillary anterior two-step retraction and en-masse retraction with clear aligners

Objective: To investigate the effects of two-step retraction and en-masse retraction on tooth movement pattern of anterior teeth and posterior anchorage with clear aligners using three-dimensional finite element analysis. Methods: A finite element model of maxillary first premolar extraction case undergoing clear aligner treatment was established based on maxillofacial cone-beam CT data of a 24-year-old adult male with individual normal occlusion, who visited Department of Oral Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine for impacted mandibular third molar in June, 2022. The initial tooth displacement of five anterior retraction protocols (two-step with canine retraction, two-step with incisor bodily retraction, two-step with incisor retraction-overtreatment, en-masse bodily retraction, and en-masse retraction-overtreatment) were evaluated. Results: Two step with canine retraction caused distal tipping of the canine and labial tipping of the incisors (0.18° for central incisor and 0.13° for lateral incisor). Two step with incisor retraction caused mesial tipping of the canine. In two step with bodily retraction protocol, uncontrolled lingual tipping was found in central incisor (0.29°) and lateral incisor (0.32°). In two-step with incisor retraction-overtreatment protocol, the movement pattern of the incisors didn't change, but the inclinations reduced to 0.21° and 0.18°. En-masse retraction caused distal tipping of the canine. In en-masse bodily retraction protocol, uncontrolled lingual tipping was also found in central incisor (0.19°) and lateral incisor (0.27°). In en-masse retraction-overtreatment protocol, the central incisor showed controlled lingual tipping (0.02°) and the lateral incisor showed palatal root movement (0.03° labial inclination). Posterior teeth exhibited mesial tipping in all five protocols. Conclusion: En-masse retraction with incisor overtreatment was beneficial to incisor torque control in clear aligner treatment.

A new torquing method for anterior tooth inclination control: a clinical report with a 7-year follow-up

Abstract Appropriate orthodontic mechanotherapy, particularly in relation to incisor inclination control is a key consideration for successful treatment and the delivery of optimal aesthetics. A novel, easy, safe and effective torquing technique, termed Park’s cervical torque tie, has been devised. A female patient sought orthodontic treatment and presented with a Class II division 2 malocclusion with crowding but a favourable facial profile. The treatment plan involved the distal movement of the maxillary posterior teeth, decrowding and incisor inclination correction. Palatal root movement was applied to the retroclined upper incisors by a novel cervical torque tie. The treatment was successfully completed after the distalisation of the dentition and palatal root movement of the upper incisors. However, following post-treatment cone-beam computed tomography, less bone coverage was evident on the palatal surface of the upper incisors. After a seven year follow-up, the treatment results were well maintained, and cortical bone regeneration was confirmed.

Comparative evaluation of variations in torque expression in maxillary incisor and canine using different bracket prescriptions placed at different crown levels by finite element (FE) method: An in-vitro analysis.

While using preadjusted brackets, the position of the bracket on the crown is one of the deciding factors that determine the tooth's final tip, torque, height, and rotation. The final tooth position is not optimal if the bracket is placed incorrectly or if the varying crown morphology does not correspond with the bracket design. The present study was conducted to evaluate and compare the variations in torque expression in maxillary incisor and canine using different bracket prescriptions placed at different crown levels by finite element method. For the present study, three-dimensional models of maxillary right central incisor and canine were made using CREO version 4.0 software. CREO is a powerful three-dimensional (3-D) computer-based, computer-aided design (CAD) software developed by Parametric Technology Corporation (PTC) to aid in design processes. Simulation was done to replicate the clinical situation of an active palatal root torque acting on the incisor and canine. The induced palatal movement of root tips and labial movement of crowns tips, overall stress, and von Mises stress generated in the brackets and the total equivalent strains developed in the periodontal ligament (PDL) were calculated, while the values obtained were tabulated and subjected to statistical analysis. Based on the findings of the present study, the average maximum stress produced in the bracket was calculated as 265.069 Mpa in incisor and 166.742 Mpa in the canine. Likewise, the average of the maximum displacement of root apex observed in the present study was calculated as 0.01401 mm in the incisor and 0.00421 mm in the canine, while the average strain developed in the PDL was calculated as 0.0587 for incisor and 0.0498 for the canine. Furthermore, it was, also, observed that the magnitude of strain developed in the PDL increased with increase in the stress produced by the bracket prescription for both incisor and canine. Within the limitations of the present study, it was concluded that the magnitude of displacement of root apex was significantly influenced by bracket prescription and bracket position. Also, the stress developed in the bracket was influenced by bracket prescription and position, while the variation in crown morphology in the incisor and canine played a significant role in the eventual strain developed in the PDL after torque application.

Torque recovery of the maxillary incisors with a modified double J retractor in a Class II division 2 case treated with clear aligners.

A patient with a Class II division 2 malocclusion is presented, illustrating the application of a modified double J retractor (DJR) and palatal miniscrews along with clear aligners to correct the malocclusion and normalize the incisor torque. In terms of incisor torque recovery, a nonextraction approach might be a good choice if the Class II correction could be successfully achieved with total arch distalization. When maxillary molar distalization was limited by anatomical boundaries, the treatment plan was changed to bilateral maxillary first premolar extractions, which led to even more retroclination of the maxillary incisors after space closure. Anterior interdental miniscrews were used to intrude the maxillary incisors. A modified DJR and palatal miniscrews were used to regain torque and achieve palatal root movement of the maxillary incisors. The treatment effects and biomechanical designs were evaluated for torque recovery of the retroclined maxillary incisors.

Validation of Earphone-Type Sensors for Non-Invasive and Objective Swallowing Function Assessment.

Standard methods for swallowing function evaluation are videofluoroscopy (VF) and videoendoscopy, which are invasive and have test limitations. We examined the use of an earphone-type sensor to noninvasively evaluate soft palate movement in comparison with VF. Six healthy adults wore earphone sensors and swallowed barium water while being filmed by VF. A light-emitting diode at the sensor tip irradiated infrared light into the ear canal, and a phototransistor received the reflected light to detect changes in ear canal movement, including that of the eardrum. Considering that the soft palate movement corresponded to the sensor waveform, a Bland–Altman analysis was performed on the difference in time recorded by each measurement method. The average difference between the time taken from the most downward retracted position before swallowing to the most upward position during swallowing of the soft palate in VF was −0.01 ± 0.14 s. The Bland–Altman analysis showed no fixed or proportional error. The minimal detectable change was 0.28 s. This is the first noninvasive swallowing function evaluation through the ear canal. The earphone-type sensor enabled us to measure the time from the most retracted to the most raised soft palate position during swallowing and validated this method for clinical application.

Arhgap29 is Required for Proper Palatogenesis and its Loss in Ectodermal‐Derived Cells Results in a Kinked Tail Phenotype

Craniofacial deformities, specifically non‐syndromic cleft lip with or without palate (NSCL/P), are among the most common class of birth defects. Complex interactions between genetic and environmental factors contribute to the development of NSCL/P. Many genes have been associated with this disease, including ARHGAP29. ARHGAP29, Rho GTPase Activating Protein (GAP) 29, functions in the cyclical regulation of the small GTPase RhoA. Previous studies have identified genetic variants of ARHGAP29 in NSCL/P and have found that ARHGAP29 levels were reduced in mice deficient for Irf6. Data from these studies suggest a role for ARHGAP29 in craniofacial morphogenesis but it remains unknown if ARHGAP29 is required for, or regulates craniofacial development. ARHGAP29 is detected in many tissues, including the oral epithelium. Using the Keratin14‐driven Cre‐recombinase allele, Krt14Cre;Arhgap29fl/fl mice displayed a delay in palatal shelf elevation and did not exhibit a cleft palate. We hypothesized that the absence of a cleft palate was due to the late activation of the Krt14‐Cre driver. EctCre drives Cre recombinase specifically in the ectoderm a couple of days before the Krt14‐Cre. Our results show that EctCre;Arhgap29fl/fl mice survive to birth and display a non‐mendelian pattern of inheritance. Interestingly, EctCre;Arhgap29fl/fl mice display a fully penetrant kinked tail phenotype, which has been described in other murine models of NSCL/P, and has been attributed to neural tube and skeletal defects. Additionally, at embryonic (E) day 14.5, while all the wild‐type embryos showed adherent palatal shelves, 75% of EctCre;Arhgap29fl/fl mice displayed palatal shelves not elevated or adherent. Our preliminary data also identified one EctCre;Arhgap29fl/fl embryo out of 3 total analyzed with a cleft palate at E18.5. These data show that ARHGAP29 is required for on‐time palatal shelves movement, supporting a role for ARHGAP29 in craniofacial development.

Palatal Tic Disorder Causing Objective Clicking Tinnitus in an 8 Years Old

Palatal tremors including myoclonus are well-known causes of objective tinnitus. Essential palatal tremors and tic disorders are recognized but rarer causes of objective pulsatile tinnitus. An 8-year-old boy presented with a chief complaint of clicking sounds in both the ears for 1 month, intermittent, occurs frequently in episodes, wherein intraoral examination revealed bilateral rhythmic, low frequency, symmetrical contractions of the soft palate muscles accompanied by clicking sounds audible to physician as well (objective tinnitus). The child's mother stated that the clicking sounds were not present when he was asleep. When the child was distracted by tuning fork sound, the palatal movements stopped. CNS examination, developmental history, birth, and growth history were all normal. Magnetic resonance imaging study with contrast enhancement was normal. The child was started on clonazepam and clonidine and follow-up was done after 1st and 2nd months. The tinnitus reduced but did not resolve completely. Clinical features of a patient with palatal tremor should be carefully assessed with prior knowledge of possible etiopathologies to guide the investigations and management. We highlight a case of palatal tic disorder to bring the possibilities quickly to the reader's mind.

A Study of Muscular Objective Tinnitus Caused by the Eustachian Tube

AbstractObjective tinnitus that originates in muscles can be heard by others as well as by the patient. Although there have been many reports of objective tinnitus, each report has been limited to a small number of cases that have varied from one another, with some being accompanied by such findings as voluntary and/or involuntary movement of the soft palate and eardrum, as well by blinking, and the etiology has remained unclear. We analyzed 16 cases of objective tinnitus synchronous with the opening and closing of the eustachian tube. The voluntary and involuntary movements of the soft palate and eardrum were consistent with the findings in previous reports. The 16 cases included 11 cases of patulous eustachian tube and in 10 of them the patient voluntary induced tinnitus to prevent the symptoms of a patulous eustachian tube. These patients created an opportunity to close the patulous eustachian tube by repeating opening and closing. The sound of the opening and closing of the eustachian tube became an objective tinnitus. The tinnitus was heard only voluntary in seven cases and voluntary and involuntarily in nine cases; one of patients was tentatively diagnosed with middle ear myoclonus and another was diagnosed with pharyngolaryngeal myoclonus. Patulous eustachian tube was first described as one of the causes of objective tinnitus. We speculated that the soft palate and eardrum movements were initially voluntary, but that some of them became involuntarily. If this involuntary movement is seen at the time of examination, it may be diagnosed as myoclonus. Psychological factors may be involved in the transitions from voluntary to involuntary, but further research will be necessary to assess this possibility.

A Report of Two Rare Cases of Palatal Tremors

Palatal tremor (PT), also known as palatal myoclonus (PM) is a very rare neurological phenomenon, manifesting as rhythmic movements of the soft palate which is hypothesized to occur either due to a lesion in the inferior olivary nucleus, or in an idiopathic manner. Prevalence data of the disease are lacking. Only a few hundred cases have been reported so far. Here we present two cases of palatal tremor, who presented to our tertiary care centre for unrelated symptoms. The first case was a 56 year old gentleman, who was incidentally found to have palatal tremor. Further investigation revealed a posterior circulation stroke involving the left cerebellar hemisphere and cerebellar peduncle. The second case, a 35 year old female, presented with an upper respiratory tract infection, and was discovered to have palatal tremor on routine examination. The cause was attributed to her history of surgical removal of a left cerebellar cyst five years ago.

Pharyngeal wall and soft palate motion after two common speech surgeries

PurposeTo assess how pharyngeal wall and soft palate motion are affected after two common interventions for velopharyngeal insufficiency. Materials and methodsA retrospective observational study was performed. A database of patients who had undergone Furlow palatoplasty or pharyngeal flap surgery between 2011 and 2019 and had video-archived preoperative and postoperative nasopharyngoscopy recordings was created. Recordings were deidentified and randomized, with 5 randomly-selected videos duplicated to determine intra-rater reliability. The videos were scored by 3 experienced raters using a modified Golding-Kushner scale. Pre- and postoperative scores were compared using paired t-test. Inter- and intra-rater reliability were estimated using intra-class correlation (ICC). ResultsThere were 17 patients who met inclusion criteria. The mean age was 6.9 years (range 3–22 years, 59% male). In the Furlow palatoplasty group (n = 9), an increase in left soft palate motion was noted postoperatively (t(8) = 2.71, p = 0.02). In the pharyngeal flap group (n = 8), increases in lateral pharyngeal wall motion (left: t(7) = 3.58, p = 0.008, right: t(7) = 3.84, p = 0.006) and right soft palate motion (t(6) = 2.49, p = 0.04) were identified. Intra-rater reliability and inter-rater agreement were lower than prior studies utilizing the Golding Kushner scale. ConclusionsOur results provide objective evidence that Furlow palatoplasty and pharyngeal flap surgeries achieve velopharyngeal closure by increasing movement at different anatomical sites. Palatal and pharyngeal wall motion observed during preoperative nasopharyngoscopy may influence a surgeon's choice of intervention.

Palato-Pharyngo-Laryngeal Myoclonus with Facial Involvement After an Ischemic Stroke.

Palatal myoclonus, also described as palatal tremor, is characterized by rhythmic continuous 0.5 to 5 Hz movements of the soft palate and pharynx.1 There are two categories described: symptomatic palatal tremor, because of a brainstem or cerebellar lesion, and essential palatal tremor, with no associated structural lesion.2, 3 Palatal myoclonus can rarely be associated with synchronous myoclonus of other branchial arch muscles, the diaphragm, facial muscles, or even the extremities.2 One specific variant is termed palato-pharyngo-laryngeal myoclonus, which can result in dysphagia, dysphonia, and dysarthria.4 A 56-year-old woman awoke from sleep with new right-sided weakness and dizziness. Magnetic resonance imaging (MRI) of the brain showed restricted diffusion in the right superomedial cerebellum consistent with an acute infarct (Fig. 1). The etiology of stroke was atheroembolism from an aortic arch plaque atheroma, for which she was started on aspirin. The follow-up MRI of the brain 4 months later showed a new fluid-attenuated inversion recovery (FLAIR) signal abnormality in the left medulla involving the left inferior olivary nucleus, reflecting hypertrophic olivary degeneration related to the chronic cerebellar infarct in the proximity of the contralateral dentate nucleus (Fig. 2). Ten months after the stroke, the patient reported a subjective, rhythmic, non-suppressible “whooshing” sound in her right ear that did not correspond to her heart rate and persisted during sleep. A computed tomography (CT) angiogram of the head and neck ruled out any vascular abnormalities. Nasopharyngolaryngoscopy showed spasm of the hypopharyngeal musculature and larynx. The patient returned to clinic to report new involuntary twitching of the right lower face. On examination, she had ~2 Hz rhythmic myoclonus of the right lip, chin, and throat (Video 1) as well as the palate (Video 2). There was no evidence of facial weakness, ocular motility problems, dysarthria, or dysphagia. She was prescribed a trial of carbamazepine 200 mg twice daily for palatal tremor followed by baclofen 5 mg twice daily with mild relief. She declined to try clonazepam or botulinum toxin injections. Palato-pharyngo-laryngeal myoclonus is a rare condition that can be idiopathic or lesional. Symptoms of palatal tremor are usually delayed 6 to 9 months after the initial injury, but can be delayed up to 30 months.1 The etiology of palatal tremor is disruption of the dento-rubro-olivary pathway, known as the Guillain Mollaret triangle. A lesion in this pathway causes denervation of olivary neurons from inhibitory cerebellar inputs, leading to hypertrophy and sustained synchronized oscillations causing tremor.2, 3 We present a unique case of palato-pharyngo-laryngeal and facial myoclonus caused by an ischemic stroke of the cerebellum. The patient also had pulsatile tinnitus, which correlated with direct visualization of spasms of the palate, hypopharyngeal musculature, and larynx via nasopharyngolaryngoscopy. Pulsatile tinnitus is most common in essential palatal tremor because of contraction of the tensor veli palatini on the eustachian tube. Although symptomatic palatal tremor affects the levator veli palatini, it can also rarely cause subjective auditory phenomena, likely because of some fibers inserting on the eustachian tube.1, 5 The patient's mild improvement in symptoms with the combination of baclofen and carbamazepine suggest a potential therapeutic option that warrants further investigation. (1) Research project: A. Conception, B. Organization, C. Execution; (2) Statistical Analysis: A. Design, B. Execution, C. Review and Critique; (3) Manuscript Preparation: A. Writing of the First Draft, B. Review and Critique. C.L.N.: 1B, 1C, 3A S.Q.: 1B, 1C, 3A M.S.: 1A, 3B Per the University of Pennsylvania Institutional Review Board, “a single retrospective case report is a medical/educational activity and does not meet the Federal Policy for the Protection of Human Subjects definition of research which is a systematic investigation, including research development, testing and evaluation, designed to develop or contribute to generalizable knowledge. Therefore, the activity does not require review by the IRB. Under HIPAA, a single case report is an activity to develop information to be shared for medical/educational purposes. Therefore, the use of protected health information to prepare a paper for publication of a single case report does not require IRB review for HIPAA purposes.” The patient provided verbal consent while at a clinic visit. The patient also provided signed/written consent which was mailed to the Neurology office. We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this work is consistent with those guidelines. No specific funding was received for this work. The authors declare that there are no conflicts of interest relevant to this work. M.S. has received clinical trial support from AbbVie, Abbott, United States (US) World Meds, and Sanofi. C.L.N. and S.Q. have no other financial disclosures to report.

Retracted: A preliminary study on the quantification of soft palate movement using ultrasonography.

Retraction: [Kumiko Fujiwara, Satoru Saitou, Naomi Nakamichi, Kei Tomihara, Hideyuki Hasegawa and Makoto Noguchi, A preliminary study on the quantification of soft palate movement using ultrasonography, Congenital Anomalies, in Early View: https://doi.org/10.1111/cga.12446]. The above article, published online on 7 October 2021 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal Editor in Chief, Toshihisa Hatta, and John Wiley & Sons Ltd. The retraction has been agreed as it has been reported by a partner in the collaboration that this research had not been reviewed/approved by their research ethics committee.

Nystagmus – What's new?

Nystagmus is defined as to-and-fro oscillations of the eyes initiated by a slow drift of the eyes away from desired position and followed by either quick phases (jerk nystagmus) or slow drifts in the opposite direction (pendular nystagmus). There are a multitude of nystagmus types, etiologies, and mechanisms – each with different clinical implications and pharmacological treatments; thus, proper pattern identification of nystagmus is critical to accurate neurological diagnosis and effective therapeutic intervention. The most common acquired nystagmus types seen clinically that occur in central gaze and thereby may cause disabling oscillopsia (i.e., a subjective sense of visual motion) are acquired pendular nystagmus (APN) and pure vertical jerk nystagmus (upbeat = UBN, downbeat = DBN). The two most common forms of APN are horizontal/elliptical APN in multiple sclerosis and vertical/torsional APN with simultaneous spontaneous palatal movements in oculopalatal tremor. Oculopalatal tremor typically begins weeks to months after a brainstem stroke and is associated with hypertrophic degeneration of the inferior olive. UBN is most common with medullary lesions from multiple sclerosis or in the setting of Wernicke encephalopathy. DBN occurs with many pathologies affecting the cerebellum, especially the cerebellar flocculus/paraflocculus or nodulus/uvula. Recent updates to be highlighted include a slowly progressive form of oculopalatal tremor called progressive ataxia and palatal tremor (PAPT) and diagnostic insights to be gained from careful examination of the behavior of UBN and DBN in different gaze positions and following provocative maneuvers (e.g., head shaking, supine position).