Forward Displacement Research Articles

DISHphagia – A Riddle Unwrapped a Clinical Case with Literature Review

Abstract Diffuse idiopathic skeletal hyperostosis (DISH) is a common but underdiagnosed systemic skeletal disease. It is characterized by calcifications affecting mainly the spinal anterior longitudinal ligament. In the majority of cases, the patients are asymptomatic, but cervical osteophytes can sometimes cause hoarseness, dysphagia (DISHphagia) and even dyspnea. Case description: A 61-year-old man was admitted to our department with complaints of difficulty in swallowing and weight loss. Dysphagia had been increasing gradually for nine months. Barium swallow esophagram revealed asymmetric swallowing with expansion above the upper esophageal sphincter without other abnormalities. The extension was confirmed by esophago-gastro-duodenoscopy (EGD). Furthermore, CT scan of the thorax clearly demonstrated degenerative changes of the cervical and thoracic region, extensive ossification of the anterior longitudinal ligament, and osteophytes from C2-C7 with a forward displacement of the esophagus by 14 mm. The so-called “wax dripping down the candle” phenomenon was as well observed. Conclusion: DISH is a systematic, musculo-skeletal disease of older adults with unknown etiology. Dysphagia is the most common symptom of the disease and might be caused by osteophytes of the cervical region. We presented a case of DISH with a rare localization of the osteophytes in the cervical region C2-C7. Due to the increasing incidence of the Forestier’s syndrome and its associated “DISHphagia”, the gastroenterologist should increase the awareness of this underestimated disease and improve the diagnostic approach.

Study & Improvement of Occupant Out-of-position Injuries Under Pre-crash Braking Condition

Although the impact strength can be reduced by AEB and other active safety technologies, the occupants may move forward under braking condition and reduce the protection space of the restraint system. The out-of-position displacement and injuries of occupants under braking conditions are studied by sled tests. The injury characteristics of the out-of-position occupant are obtained. By orthogonal tests, the influence of out-of-position on the injury of different body regions are analysed. MADYMO active human body simulation model is established, and the characteristics of the occupant forward displacement under different braking waveforms are studied by single variable method. By using the active seatbelt, the occupant’s forward displacement is restrained. With the use of Central Composite Design (CCD) method, the response surface model of the occupant’s neck displacement relative to the pretension force and pretension time of the active seatbelt is established. The effects of pretension force and pretension time on out-of-position displacement are studied, and the optimal design is carried out to obtain the parameter combination.

Skeletal effects of mini-implant assisted rapid palatal expansion (MARPE) on the sagittal dimensions of the maxilla an in-vivo cone-beam computed tomography (CBCT) study

Introduction -Transverse discrepancies of the maxilla are one of the most prevalent skeletal problems. Due to drawbacks of conventional RPE and invasive surgical expansion methods alternative methods were developed such as Mini Implant-supported rapid maxillary expansion (MARPE).Haas17 , Davis and Kronman18, Akkaya et al19 and many other studies have reported the maxillary response after MARPE on the sagittal dimensions, but their results were inconclusive.
 Aim - This study analyzed the effects on the maxilla in the sagittal dimension after Mini Implant assisted rapid palatal expansion (MARPE) in adolescents using CBCT.
 Material and method -A pretreatment CBCT image (T1) was taken as a standard initial record for all patients and post treatment CBCT (T2) was taken after three months in retention. The parameters SNA angle, Frankfort horizontal plane to NA angle, A-N perpendicular, ANS –PNS were measured and calculated for evaluation of the sagittal maxillary changes. Comparisons were then made between the two treatment groups (T1, T2).
 Result -There was a positive increase in both angular and linear measurements from pretreatment to post treatment measurements showing significant skeletal changes in sagittal dimension.
 Conclusion -The study concludes that there was statistically significant forward displacement of maxilla after transverse skeletal expansion in patients with transverse problems achieved through MARPE in adolescent patients.

Design and Analysis of a Stepping Piezoelectric Actuator Free of Backward Motion

Although the stick-slip principle has been widely employed for designing piezoelectric actuators, there still exits an intrinsic drawback, i.e., the backward motion, which significantly affects its output performances and applications. By analyzing the generation mechanism of backward motion in stick-slip piezoelectric actuators, the elliptical trajectory was employed to design a novel stepping piezoelectric actuator free of backward motion. Accordingly, a prototype of piezoelectric actuator was designed, which utilized a flexure hinge mechanism and two vertically arranged piezoelectric stacks to generate the required elliptical trajectory. The compliance matrix method was used to theoretically analyze the flexure hinge mechanism. The theoretical and measured elliptical trajectories under various phase differences were compared, and the phase difference of 45° was selected accordingly. Under a critical relative gap, output performances of the actuator working under the elliptical trajectory were characterized, and then compared with that obtained under the normal stick-slip driving principle. Experimental results indicated that forward and reverse stepping displacement with completely suppressed backward motion could be achieved when employing the elliptical trajectory, verifying its feasibility. This study provides a new strategy for designing a stepping piezoelectric actuator free of backward motion.

Design of a small wheel-foot hybrid firefighting robot for infrared visual fire recognition

The complex and changeable environment and the different degrees of toxic hot smoke and unknown danger at fire scenes can seriously affect the fire personnel’s reconnaissance, fighting, and life safety. To address these challenges, in this study, we developed a small wheel-foot hybrid firefighting robot based on an infrared vision fire recognition system. The robot mainly involves a mechanical system, walking system, fire extinguishing system, and control system. First, the whole system and each individual system were designed and analyzed, and the visual recognition system was developed to test the recognition rate. Second, the kinematics method was used to calculate the position coordinates of the robot’s gait, and dynamic analysis of the robot’s gait process was performed. Finally, the climbing ability of the prototype model of the gait walking device was tested. The experiments showed that the average recognition rate of the flame recognition algorithm was 97.8%, and the overall detection effect was good. The robot had good terrain adaptability, and its gait uplift and forward displacement met the requirements of complex terrain conditions, such as climbing stairs. The climbing efficiency was proportional to the angular speed of the motor within a certain range.

Symposium 3: Motor neuron disease SY3.1. Monomelic amyotrophy – Experience from a large cohort

In 1959, Hirayama described the clinical entity of progressive atrophy of distal muscles of a single upper limb and called it Hirayama disease (HD). Later on Gourie-Devi from India coined the term Monomelic Amyotrophy. The other phenotypes described by us are: Distal Bimelic, Proximo-distal bimelic and unilateral/bilateral proximal amyotrophy. Illness has sporadic occurrence with male preponderance, but familial forms are also reported. Most cases are described from Asian countries. There is insidious onset and slowly progressive weakness and atrophy of intrinsic hand and forearm muscles, with oblique atrophy with sparing of Brachioradialis and reverse split hand syndrome. Typically, they have cold paresis. In the year 2000, HD was confirmed to occur secondary to dynamic compression of the lower Cervical Cord due to forward displacement of the tight cervical dural sac causing arterial/venous ischemic damage to anterior horn cells. Classically MRI at cervical level shows “eye of the snake” appearance, reverse lordosis, dural detachment with forward displacement and epidural venous congestion and enhancement. From our experience on 480 cases seen over 38 years, the mean age at onset is 19.5 years; range,15–25 years, with majority being in the progressive phase. Progression generally occurs over 5 years but even rapidly and slower in certain cases, and the disability is moderate to severe in the majority. Rarely patients experienced Lhermitte’s phenomenon and had spasticity of the lower limbs with sphincter disturbance. Over the last 4.5 years, 101 cases with HD have undergone anterior cervical decompressive surgery at our center. Predominantly C5-C6 single level discectomy and fusion was performed. Pre-operative and serial post-operative assessment included, Fugl Meyer and Jebsen Taylor hand function tests which demonstrated significant improvement in functions in the majority at 3,6,12 and 24 months follow-up. In the remaining patients the illness has stabilized. No major complications were encountered except for post-operative neck pain and restricted movements which improved in a few weeks. To conclude Hirayama disease is now confirmed to be a cervical compressive myelopathy due to dynamic neck flexion induced ischemic damage and surgery has a major role in stabilizing / improving the neurological deficits. The most appropriate term for this disease would be “CERVICAL FLEXION INDUCED MYELOPATHY”.

Facial Nerve Palsy After Ear Infection: A Case Report

<strong>Introduction:</strong> The incidence of acute mastoiditis, a common complication of otitis media, has significantly decreased with the emergence of antibiotic therapy [1]. Classical symptoms of acute mastoiditis include fever, irritability, otalgia, swelling of the mastoid area, and retroauricular erythema [2]. Delay in appropriate antibiotic treatment of mastoiditis may lead to intracranial and extracranial complications. Facial nerve paralysis is a rare complication of otomastoiditis with different pathophysiologic mechanisms postulated [3]. Extensive literature search showed cases of lower motor neuron involvement of the facial nerve in affected patients. We report an unusual case of mastoiditis without fever complicated by epidural abscess and upper motor neuron facial nerve palsy in a previously healthy adolescent. <strong>Case Presentation:</strong> A 13-year-old male presented with painful progressive swelling behind his left ear of 5 days duration. Symptoms had started 2 weeks prior with complaints of left ear pain, and he was diagnosed with impacted cerumen and prescribed topical hydrogen peroxide. There was no history of fever, ear discharge, hearing loss or change in neurologic status. On admission, physical examination showed 4x4 cm tender swelling over the left mastoid region with forward displacement of the pinna and cerumen impaction. Neurological assessment was normal. Laboratory investigations showed peripheral leukocytosis (12,200 cells/uL) with neutrophilia (74%), and elevated c-reactive protein (87 mg/L). Head CT scan showed acute coalescent left mastoiditis with small left epidural abscess formation, displacing the left sigmoid sinus medially, and a developing left mastoid subperiosteal abscess (see <em><strong>Figure 1</strong></em>). A diagnosis of acute mastoiditis was made, and he was commenced on intravenous ceftriaxone and vancomycin with resultant decrease in size of the swelling and normalization of inflammatory markers. On the third day of admission, the patient developed mild right-sided facial asymmetry with sparing of the upper part of the face. Ceftriaxone was changed to piperacillin-tazobactam for broader-spectrum anerobic and gram-negative coverage. Otolaryngology evaluation revealed Bezold’s abscess requiring mastoidectomy. The father initially declined, given improvement in the patient’s symptoms, but consented to wide myringotomy and placement of a short-term myringotomy tube for further drainage and middle ear irrigation. Samples of pus collected were sent for aerobic, anaerobic, mycobacterial, and fungal cultures which all came back negative except for scant growth of Staphylococcus epidermidis. MRI done on the second post-operative day showed severe coalescent left otomastoiditis, mild meningeal enhancement compatible with meningitis along the left lateral temporal lobe, and a small sliver of epidural abscess along the left infratemporal fossa (see <em><strong>Figure 2</strong></em>). Antibiotic treatment was escalated from Piperacillin-tazobactam to meropenem to provide a broader gram-negative and anaerobic coverage. At this point, father consented, and patient underwent mastoidectomy with craniotomy and epidural abscess drainage. Patient received 14 days of parenteral antibiotics. He showed clinical and radiological improvement on repeat MRI, facial asymmetry resolved and patient was discharged home in stable condition to complete 1-month of oral antibiotics (levofloxacin + amoxicillin-clavulanate) with subsequent outpatient follow-up. <strong>Conclusion:</strong> Mastoiditis is a complication of otitis media that can lead to potentially life-threatening intracranial complications. Interestingly, the patient developed rightsided facial asymmetry sparing the upper part of the face suggesting a left upper motor neuron facial nerve palsy with involvement of the contralateral face. This finding is unique to our case, and to our knowledge has not been described in literature. A plausible anatomic explanation is the involvement of ipsilateral corticobulbar tract with subsequent interruption of the main input to the lower portion of contralateral facial nerve nucleus which controls the muscles of the lower face [4]. This results in sparing of the upper facial muscles characteristic of upper motor neuron lesion. Appropriate antibiotic treatment with surgical intervention led to complete resolution of symptoms.

Midfacial soft tissue changes after maxillary expansion using micro-implant-supported maxillary skeletal expanders in young adults: A retrospective study.

ObjectiveThe aim of this retrospective study was to assess the midfacial soft tissue changes following maxillary expansion using micro-implant-supported maxillary skeletal expanders (MSEs) in young adults by cone-beam computerized tomography (CBCT) and to evaluate the correlations between hard and soft tissue changes after MSE usage.MethodsTwenty patients (mean age, 22.4 years; range, 17.6–27.1) with maxillary transverse deficiency treated with MSEs were selected. Mean expansion amount was 6.5 mm. CBCT images taken before and after expansion were superimposed to measure the changes in soft and hard tissue landmarks. Statistical analyses were performed using paired t-test and Pearson’s correlation analysis on the basis of the normality of data.ResultsAverage lateral movement of the cheek points was 1.35 mm (right) and 1.08 mm (left), and that of the alar curvature points was 1.03 mm (right) and 1.02 mm (left). Average forward displacement of the cheek points was 0.59 mm (right) and 0.44 mm (left), and that of the alar curvature points was 0.61 mm (right) and 0.77 mm (left) (p < 0.05). Anterior nasal spine (ANS), posterior nasal spine (PNS), and alveolar bone width showed significant increments (p < 0.05). Changes in the cheek and alar curvature points on both sides significantly correlated with hard tissue changes (p < 0.05).ConclusionsMaxillary expansion using MSEs resulted in significant lateral and forward movements of the soft tissues of cheek and alar curvature points on both sides in young adults and correlated with the maxillary suture opening at the ANS and PNS.

Movement characteristics analysis of bi-directional friction linear micro-motor driven by a set of micro-actuator

In this paper, a bi-directional friction linear micro-motor (BFLM) driven by a set of micro-actuators was introduced and analyzed. The BFLM was fabricated using PolyMUMPs process. The impact dynamics model for the BFLM was established, and its motion equation was also derived that takes into account the friction and contact. The relative motion between the driving head and the slider, as well as forward or backward movement of the slider were analyzed in detail. The forward and backward movement displacement of the slider was measured, and the experimental results were in good agreement with theoretical predictions. The theoretical results show that the motion direction of the slider can be changed by controllable driving frequency to the BFLM. It was feasible to use a set of actuators to drive the slider in bi-directional motion.

The effect of change in mass distribution due to defensive posture on gait in fat-tailed scorpions.

In terrestrial legged locomotion, the distribution of mass can influence the gait characteristics. This can be due to a change in the magnitude or distribution of the load. The latter occurs in scorpions when they lift their large metasoma from a trailing position in ambulatory posture to the well-known arched forward position in the defensive posture. We measured how locomotion changes between these two postures by recording scorpions walking using high-speed video. We found that the metasoma in the fat-tailed scorpion (Androctonus australis) represents about a quarter of the total mass. Moving this mass anteriorly over the body changes the position of the center of mass forward 8.15 ± 1.86mm. We found this increases the overall duty factor, and particularly that of the second leg pair, even when taking the reduced speed in defensive posture into account. In the five scorpions we recorded, also the ipsilateral phase of leg pairs 3 and 4 differed in defensive posture. We found that the trajectory the 4th foot describes during a single stride also differed significantly between postures, showing this to be a sensitive measure of changes in gait. The change from an ambulatory to a defensive posture places different demands on the gait of scorpions, possibly largely due to the forward displacement of the center of mass.

A Novel Geometric Modeling and Calculation Method for Forward Displacement Analysis of 6-3 Stewart Platforms

A novel geometric modeling and calculation method for forward displacement analysis of the 6-3 Stewart platforms is proposed by using the conformal geometric algebra (CGA) framework. Firstly, two formulas between 2-blade and 1-blade are formulated. Secondly, the expressions for two spherical joints of the moving platform are given via CGA operation. Thirdly, a coordinate-invariant geometric constraint equation is deduced. Fourthly, a 16-degree univariate polynomial equation without algebraic elimination by using the Euler angle substitution is presented. Fifthly, the coordinates of three spherical joints on the moving platform are calculated without judging the radical symbols. Finally, two numerical examples are used to verify the method. The highlight of this paper is that a new geometric modeling and calculation method without algebraic elimination is obtained by using the determinant form of the CGA inner product algorithm, which provides a new idea to solve a more complex spatial parallel mechanism in the future.

Torque responses to in-place-perturbations in people with multiple sclerosis

BackgroundAutomatic postural responses are critical to prevent falls after a loss of balance. Although responses have been shown to be delayed in people with multiple sclerosis (PwMS), the degree to which other aspects of these movements are impacted by MS remains unknown. Research QuestionDo responses to in-place support-surface perturbations differ in PwMS compared to neurotypical adults? Are these responses related to a functional measure of postural response performance- center of mass (COM) displacement?. Method52 PwMS and 20 neurotypical, age-matched adults (NA) experienced backward support surface perturbations resulting in forward loss of balance and requiring an in-place response. Center of pressure (COP) and torque were calculated from force plates while center of mass (COM) approximations were collected via motion capture. Primary outcomes were maximal torque production at the foot and its timing, rate, and onset. ResultsPwMS and NA demonstrated no differences in maximal torque production (p = 0.79), timing of maximal torque (p = 0.29), rate of torque development (p = 0.76), or the onset of AP COP movement (p = 0.44). There was a significant negative association between the rate of torque development and forward COM displacement in both groups (Control: r=-0.64, p = 0.002; MS: r=-0.35, p = 0.01). Larger maximal torque production was also associated with smaller COM displacement in PwMS (r=-0.33, p = 0.02). ConclusionTorque profiles in response to backward support surface translations resulting in feet in-place responses were similar in people with mild MS and neurotypical adults. The rate of development and maximal torque were however correlated to functional postural response outcomes. These findings suggest that while not worse in PwMS during in-place perturbations, force-responses seem to be important predictors of the effectiveness of reactive postural control responses.

3D Finite Element Analysis of the Effects of Lefort I Corticotomy on the Temporomandibular Joint (TMJ) and Maxilla in Skeletal Class III Malocclusion Patients

Objective: The purpose of this study was to evaluate the influence of Lefort I corticotomy using two skeletally anchored maxillary protraction protocols on temporomandibular joint (TMJ) and maxilla of skeletal class III malocclusion patients using three-dimensional finite element analysis. Methods: Protraction forces of 500 gm per side were applied on maxilla with two different types of Lefort I corticotomy, type A and type B osteotomy using two skeletally anchored maxillary protraction appliances: skeletally anchored facemask and bone-anchored with class III traction. Results: For the facemask appliance the osteotomy types presented clockwise rotation in contrast with bone-anchored with class III traction which showed counter-clockwise rotation. Within the sagittal plane, the most significant amount of anterior displacement was associated with bone-anchored with class III traction type A osteotomy. For the temporomandibular joint, the maximum stress distribution was concentrated in the anterior aspect condyle and superior aspect of the glenoid fossa for the two appliances. However, the stress distribution in bone-anchored with class III traction was more than skeletally anchored facemask. Conclusion: Using Lefort I corticotomy can be a useful alternative for maxillary protraction in adult patients. Bone anchored with class III traction was more effective for maxillary forward displacement than skeletally anchored facemask. However, the stress distribution on TMJ in bone-anchored was more than that in the facemask. However, the amount of rotation in type A cutting was more than in type B cutting.

Management of lumbar degenerative spondylolisthesis by integrated naturopathy and yoga therapy: a case report

Spondylolisthesis is the forward displacement of a vertebra relative to the vertebra below, and it arises as a result of a pars defect. Lumbar degenerative spondylolisthesis is an established condition, and it classically involves the L4/L5 level with mild degenerative changes; the symptoms vary from lower back pain to lower limb radiculopathy depending on the severity. The present case reported was of a 57-year-old married woman diagnosed with lumbar degenerative spondylolisthesis after an accidental fall; her symptoms began with severe pain and numbness in both legs radiating from her buttock region. This case study was done to investigate the effectiveness of combined Yoga and naturopathy therapy in relieving degenerative pain. The subject received a specific yoga protocol, which includes Yogasanas, Pranayama, and relaxation techniques along with naturopathy treatments, including hydrotherapy, acupuncture, and natural diet therapy for 30 days. According to the findings of the visual analogue scale (VAS) and SF-MPQ-2 scale, the pain symptoms score changed from 9.2 to 1.3 and from 79 to 20, respectively. This result shows that the combined effect of Yoga and naturopathy treatment helps in relieving pain and improves the quality of life in patients with degenerative spondylolisthesis.

Skeletal changes produced by cervical and parietal headgears: a cephalometric evaluation

Abstract Introduction Extraoral strength is the most common strategy to correct Angle Class II malocclusion, restricting and redirecting the maxillary growth. Objective To evaluate the skeletal changes resulting from the use of headgear, with cervical and parietal anchorages, associated with a full fixed orthodontic appliance, in growing patients with Class II malocclusion (Angle) treated in the clinic of an orthodontic training center. Material and method The ages at the beginning and end of the treatment, anchorage type, and the values of some cephalometric variables were obtained from the clinical files. After applying the inclusion and exclusion criteria, 56 patient files were selected. Then, the sample was divided into two groups, according to the anchorage type: cervical (n=30) and parietal (n=26). The differences between the initial (T1) and final (T2) values of cephalometric measurements SNA, SNB, ANB, AO-BO, GoGn.SN and LHF (percentage of lower facial height to total facial height) were evaluated in both groups. Result Significant differences between T1 and T2 were found relative to SNB and ANB variables in both groups. The AO-BO variable presented a statistically significant difference only in the cervical group. The remaining variables did not show significant differences between T1 and T2. Conclusion The skeletal changes resulting from the use of cervical or parietal anchorage were very similar. There was a decrease in the sagittal discrepancy between the maxillary bones due to forward displacement of the mandible, without significant vertical changes.

An inverse modelling study on the local volume changes during early morphoelastic growth of the fetal human brain

We take a data-driven approach to deducing the local volume changes accompanying early development of the fetal human brain. Our approach uses fetal brain atlas MRI data for the geometric changes in representative cases. Using a nonlinear continuum mechanics model of morphoelastic growth, we invert the deformation obtained from MRI registration to arrive at a field for the growth deformation gradient tensor. Our field inversion uses a combination of direct and adjoint methods for computing gradients of the objective function while constraining the optimization by the physics of morphoelastic growth. We thus infer a growth deformation gradient field that obeys the laws of morphoelastic growth. The errors between the MRI data and the forward displacement solution driven by the inverted growth deformation gradient field are found to be smaller than the reference displacement by well over an order of magnitude, and can be driven even lower. The results thus reproduce the three-dimensional growth during the early development of the fetal brain with controllable error. Our findings confirm that early growth is dominated by in plane cortical expansion rather than thickness increase. Statement of SignificanceThe points of significance of our work are:•A data-driven approach to deducing the local volume changes accompanying early development of the fetal human brain from MRI registration.•The combination of direct and adjoint methods while constraining the optimization by the physics of morphoelastic growth.•Reproduction of the three-dimensional growth during the early development of the fetal brain with controllable error.•To our knowledge, the first data-driven confirmation underlying the morphoelastic theory that early growth is dominated by in-plane cortical expansion rather than thickness increase.•To our knowledge, the first data-driven confirmation underlying the morphoelastic theory that early growth is radially distributed, increasing along the ventricular-cortical direction.

Mechanisms of Negative Fetal Outcome in Frontal Vehicle Colli-Sions Involving Unbelted Pregnant Drivers.

To determine the cause of negative fetal outcomes and the causative mechanism in a frontal collision, we analyzed the kinematics and mechanisms of injuries using an unbelted pregnant dummy, the Maternal Anthropometric Measurement Apparatus dummy, version 2B. Sled tests were performed to recreate frontal impact situations with impact speeds of 13, 26, and 40 km/h. Overall kinematics of the dummy were examined through high-speed video imaging. Quantitative dummy responses—such as time courses of the abdominal pressure, chest deflection, neck injury criteria (Nij), and displacement of the pelvis during impact—were also measured. The maximum abdominal pressure of 103.3 kPa was obtained at an impact speed of 13 km/h. The maximum chest deflection of 38.5 mm and Nij of 0.36 were obtained at an impact speed of 26 km/h. The highest maximum chest deflection of >40.9 mm, Nij of 0.61, and forward pelvis displacement of 478 mm were obtained at an impact speed of 40 km/h. Although the kinematics and mechanism of injuries of the dummy were different for different collision speeds, we found that unbelted pregnant drivers suffer severe or fatal injuries to the fetus even in low-speed collisions.

Somatosensory evoked potentials in Hirayama disease: A Brazilian study.

Background: Hirayama’s disease (HD) is characterized by an insidious onset asymmetric weakness and atrophy of the forearm and hand. Taking as a premise, the etiopathogenesis of the disease is attributed to forward displacement of posterior wall of lower cervical dural canal in neck flexion causing marked compression and flattening of lower spinal cord. This may result in compression of the posterior column of the spinal cord and seems likely to result in somatosensory evoked potentials (SSEPs) abnormalities. In the present study, we studied the possible involvement of the lemniscal dorsal pathway in patients with HD.Methods: SSEPs in upper and lower extremities were prospectively performed in eight patients with HD. All the patients were recruited from the outpatient clinic of a neuromuscular disorder center from South Brazil. SSEPs were obtained by transcutaneous electrical stimulation of the median and posterior tibial nerves, on both sides. We collected the amplitude and the latency of the different components obtained in each channel. The interpretation was based on Brazilian study standards.Results: We evaluated seven men and one woman (mean age 27). The data obtained were compared to a control group consisting of eight patients with spondylotic cervical myelopathy, 6 men and 2 women with mean age of 59 years. The measurements of obtained by the SSEP were also compared between the groups and no significant difference was found for any of them.Conclusion: SSEP did not turn out to be an electrophysiological marker in our HD patients.

Impact of ablation ratio on 5-year postoperative posterior corneal stability after refractive surgery: SMILE and FS-LASIK

BackgroundTo investigate the impact of the ablation ratio on 5-year postoperative posterior corneal stability in myopic eyes after small incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) surgery.MethodsA prospective, nonrandomized, cohort study: 80 eyes of 43 patients underwent SMILE surgery and 63 eyes of 32 patients underwent FS-LASIK surgery at the EYE & ENT Hospital, Fudan University. Ablation ratio was defined as lenticule thickness (SMILE cases) or ablation depth (FS-LASIK cases) divided by central corneal thickness (CCT). Posterior corneal elevation changes were recorded as posterior central elevation (PCE), posterior corneal surface at thinnest point (PTE) and posterior corneal mean elevation (PME). Patients were followed up at 6-month and 5-year interval to investigate the impact of the ablation ratio on posterior corneal elevation after SMILE and FS-LASIK surgery.ResultsPCE dropped at the 6-month follow-up for both SMILE (decreased by −1.11 ± 2.93 μm, P < 0.05) and FS-LASIK groups (decreased by −0.46 ± 3.72 μm, P < 0.05). PTE also dropped in SMILE (reduced by −2.04 ± 3.02 μm, P < 0.05) and FS-LASIK group (reduced by −1.28 ± 4.21 μm, P < 0.05) at the 6-month follow-up. Stable PCE (elevation change: SMILE −0.28 ± 4.03 μm; FS-LASIK 0.79 ± 4.13 μm, P > 0.05) and PTE (elevation change: SMILE −0.08 ± 4.28 μm; FS-LASIK 1.42 ± 3.85 μm, P > 0.05) for both groups were recorded at the 5-year follow-up compared to the 6-month visit. Ablation ratio was strongly correlated with 5-year postoperative PCE (β = 2.68 ± 1.05, P < 0.01) and PTE (β = 2.35 ± 1.17, P < 0.05). Cut-off value for 5-year postoperative raised PCE and PTE was 27.3 and 27.1%, respectively.ConclusionsAblation ratio was strongly correlated with postoperative posterior corneal elevation in a 5-year follow-up in both SMILE and FS-LASIK groups. PCE and PTE underwent slight backward displacement 6-month postoperatively and remain stable at the 5-year follow-up. Threshold of the ablation ratio for resisting forward displacement of posterior corneal surface was 27.3 and 27.1% for SMILE and FS-LASIK groups, respectively.

Surgical treatment of forward displacement of the uterus.

Based on statistics from Nonat, meadovs, Scanzoni, Mund, and others, we must assume, says the author, that of all uterine displacements, forward displacements are the most frequent, and yet it is precisely in the treatment of these displacements that gynecology is powerless.