Use of ultrasound shear wave to measure muscle stiffness in children with cerebral palsy

Upper and lower limb muscle stiffness in children with cerebral palsy compared to typically developing children: Insights from shear wave elastography

Children with spastic cerebral palsy (CP) experience altered muscle tone due to biomechanical changes, traditionally assessed through clinical scales. Shear wave elastography (SWE) offers a non-invasive way to quantify these changes. This study aimed to compare SWE measurements in spastic CP and typically developing (TD) children and investigate influencing factors such as joint position, range of motion, demographics, physical condition and, in CP children, the characteristics of CP. It also examined correlations between SWE measurements and spasticity scales in CP children. SWE measured the elastic modulus (kPa) of biceps brachii (BB), pronator teres (PT), adductor longus (AL), lateral gastrocnemius (LG), and soleus (SOL) muscles at rest and during maximum passive stretching (MPS) in 34 spastic CP children (age: 3-17) and 44 TD children (age: 3-14). Significant differences (p < 0.05) in SWE were found between CP and TD children. CP children had lower values in upper limb muscles and higher values in lower limb muscles at rest, with the opposite pattern during MPS. The Ashworth and Tardieu scales were associated with the elastic modulus in lower limb muscles (AL, GL, and SOL) at rest in CP children. Differences in elastic modulus at rest and MPS between upper and lower limbs and in spastic CP and TD children showed no consistent links to spasticity scales, reflecting neurological dysregulation, muscle architecture, and joint structure involvement. These variations were linked to neurological dysregulation and muscle architecture, with joint structures also affecting. SWE may offer a more precise assessment of muscle spasticity, minimizing the impact of confounding joint structures.

The use of shear-wave elastography for the assessment of muscle spasticity in patients with cerebral palsy, a systematic review

We explore the use of shear wave elastography (SWE) for assessing muscle stiffness and treatment response in cerebral palsy (CP) children by way of a systematic review. SWE offers real-time muscle stiffness measurements, showing significant differences between CP patients and controls. Studies suggest that SWE can be used to follow muscle stiffness post-botulinum toxin treatment, correlating with clinical improvement. However, methodological variations and small sample sizes prevent comparison between different studies. Standardized protocols could enhance SWE's clinical utility. In conclusion, SWE holds promise for CP management, though standardized methodologies and larger studies are needed to validate its efficacy and integration into clinical practice.

Impact of lower muscle stiffness on ankle dorsiflexion restriction in children with cerebral palsy evaluated using ultrasound elastography

BACKGROUND

Plantar flexor muscles always contribute to limiting the range of motion of ankle dorsiflexion in children with spastic cerebral palsy, but the individual contributions of these muscles are not well defined. This study aimed to identify which muscles' stiffness impacts the dorsiflexion range of motion in children with cerebral palsy.

METHODS

Twenty-five children with cerebral palsy were included. The maximum passive dorsiflexion range of motion was measured in two positions: hip and knee joints in flexion, and both joints in full extension. Strain ratios indicating muscle stiffness were measured using strain elastography of the lateral and medial gastrocnemius, soleus, flexor hallucis longus, peroneus longus, peroneus brevis, and tibialis posterior muscles. To analyze which muscles impact the limitation of the dorsiflexion range, multiple regression analyses were conducted. The values of muscle stiffness were included as independent valuables, and the values of the dorsiflexion range were included as dependent valuables. A p-value <0.05 was considered statistically significant.

FINDINGS

In the analyses, the soleus and flexor hallucis longus muscle stiffness were significant independent factors for the dorsiflexion range of motion of hip and knee flexion (adjusted R2: 0.50). The lateral gastrocnemius muscle stiffness was a significant independent factor for the dorsiflexion range of motion with both joints in full extension (adjusted R2: 0.61).

INTERPRETATION

Flexor hallucis longus muscle stiffness, in addition to triceps surae muscle stiffness, was shown to impact dorsiflexion range; attention should be paid to muscle stiffness in children with cerebral palsy.

Shear wave imaging the active constitutive parameters of living muscles

Shear wave elastography (SWE) of human skeletal muscles allows for measurement of muscle elastic properties in vivo and has important applications in sports medicine and for the diagnosis and treatment of muscle-related diseases. Existing methods of SWE for skeletal muscles rely on the passive constitutive theory and have so far been unable to provide constitutive parameters describing muscle active behavior. In the present paper, we overcome this limitation by proposing a SWE method for quantitative inference of active constitutive parameters of skeletal muscles in vivo. To this end, we investigate the wave motion in a skeletal muscle described by a constitutive model in which muscle active behavior has been defined by an active parameter. An analytical solution relating shear wave velocities to both passive and active material parameters of muscles is derived, based upon which an inverse approach has been developed to evaluate these parameters. To demonstrate the usefulness of the reported method, in vivo experiments were carried out on 10 volunteers to obtain constitutive parameters, particularly those describing active deformation behaviors of living muscles. The results reveal that the active material parameter of skeletal muscles varies with warm-up, fatigue and rest. STATEMENT OF SIGNIFICANCE: Existing shear wave elastography methods are limited to imaging the passive parameters of muscles. This limitation is addressed in the present paper by developing a method to image the active constitutive parameter of living muscles using shear waves. We derived an analytical solution demonstrating the relationship between constitutive parameters of living muscles and shear waves. Relying on the analytical solution, we proposed an inverse method to infer active parameter of skeletal muscles. We performed in vivo experiments to demonstrate the usefulness of the theory and method; the quantitative variation of the active parameter with muscle states such as warm-up, fatigue and rest has been reported for the first time.

Quantitative assessment of biceps brachii muscle stiffness by using Young’s modulus–Angle curve during passive stretching in stroke patients

Purpose: This study aims to use shear wave elastography (SWE) to dynamically describe the characteristics of biceps brachii muscle stiffness during passive stretching in healthy participants, investigate changes in the Young’s modulus–angle curve under various states of muscle tone in stroke patients, and develop a new method for measuring muscle tone quantitatively.

Methods: In total, 30 healthy volunteers and 54 stroke patients were evaluated for elbow flexor muscle tone on both sides using passive motion examination and were divided into groups based on their muscle tone status. The real-time SWE video of the biceps brachii and the Young’s modulus data were recorded during the passive straightening of the elbow. The Young’s modulus–elbow angle curves were created and fitted using an exponential model. The parameters yielded from the model were subjected to further intergroup analysis.

Results: The repeatability of the Young’s modulus measurement was generally good. During passive elbow extension, the Young’s modulus of the biceps brachii steadily increased as muscle tone increased, and it increased faster when the modified Ashworth scale (MAS) score got higher. The exponential model’s fitness was generally good. The curvature coefficient was significantly different between the MAS 0 group and the hypertonia groups (MAS 1, 1+, and 2 groups).

Conclusion: The passive elastic characteristics of the biceps brachii are consistent with the exponential model. The Young’s modulus–elbow angle curve of the biceps brachii changes in distinct ways depending on the muscle tone status. SWE can be used to quantify muscular stiffness during passive stretching as a new way of muscle tone evaluation, allowing for quantitative muscle tone evaluation and mathematical assessment of muscle mechanical properties in stroke patients.

Shear Wave Velocity to Evaluate the Effect of Botulinum Toxin on Post-Stroke Spasticity of the Lower Limb

(1) Background: The evaluation of muscles with spasticity using ultrasound elastography has attracted attention recently, and the shear wave velocity (SWV) technique can measure the mechanical properties of tissues objectively and quantitatively. The purpose of this study was to evaluate the effect of using SWV to assess the effect of Botulinum toxin type A (BoNT-A) treatment in adult patients with post-stroke lower limb spasticity. (2) Methods: We assessed the modified Ashworth Scale, the modified Tardieu Scale, and SWV at rest and after stretching before and at 1 month after BoNT-A treatment in 10 adult participants with post-stroke lower limb spasticity. (3) Results: Significant changes in SWV of the ankle joint in maximum dorsiflexion to the extent possible (SWV stretched) were observed after BoNT-A treatment. SWV stretched was positively correlated with joint range of motion. Participants whose joint range of motion did not improve (i.e., gastrocnemius medialis muscle (GCM) extension distance did not change) had significantly more reductions in SWV stretched after BoNT-A treatment. (4) Conclusions: Our results suggest that the SWV measurements may serve as a quantitative assessment to determine the effect of the BoNT-A treatment in adult stroke patients. SWV measurements to assess GCM spasticity should consider the effects of tension, material properties and activation level of muscles. The challenge is to measure SWV with matching limb positions in patients without contractures.

Ultrasound shear-wave elastography applicability in estimation of post-mortem time

Introduction

Post-mortem rigidity of the tissues is one of the basic principles in forensic medicine to estimate the time of death. Qualitative methods to determine the stiffness of the corpse may have some limitations. Methods that provide quantitative values may be useful. We intended to evaluate the applicability of ultrasound shear-wave elastography of the tissues to estimate the post-mortem interval (PMI).

Methods

For 80 corpses, shear-wave elastography of the liver, sartorius muscle, testis, thyroid and parotid was performed before autopsy. Based on the forensic reports as the reference method to define post-mortem interval, the corpses were divided into four groups: group 0 (PMI < 24 hours), group 1 (PMI ≥24 hours and <48 hours), group 2 (PMI ≥ 48 hours and <72 hours), and group 3 (PMI ≥ 72 hours). There were 24, 38, 13, and 5 corpses, respectively, in groups 0, 1, 2, and 3.

Results

A significant rise in the elasticity values in comparison to elasticity of normal tissues in live adults was seen very early in the post-mortem period. Between-group comparisons showed that a significant difference in the liver elasticity was present among the groups. The mean (SD) liver elasticity was 10.29 (±0.83) in group 0, 14.98 (±1.56) in group 1, 12.49 (±1.09) in group 2, and 15.64 (±1.68) kilopascals (kPa) in group 3 (P = 0.035). Nevertheless, elasticity measurements in other tissues were not helpful in distinguishing post-mortem interval groups.

Conclusion

It is possible to use liver quantitative shear-wave elastography to estimate the time of death.

Botulinum Toxin a Injection Combined with Radial Extracorporeal Shock Wave Therapy in Children with Spastic Cerebral Palsy: Shear Wave Sonoelastographic Findings in the Medial Gastrocnemius Muscle, Preliminary Study

Therapeutic strategies to boost the effect of botulinum toxin may lead to some advantages, such as long lasting effects, the injection of lower botulinum toxin dosages, fewer side effects, and lower costs. The aim of this study is to investigate the combined effect of botulinum toxin A (BTA) injection and extracorporeal shock wave therapy (ESWT) for the treatment of spasticity in children with spastic cerebral palsy (CP). Fifteen patients with spastic CP were recruited through a retrospective chart review to clarify what treatment they received. All patients received a BTA injection on gastrocnemius muscle (GCM), and patients in group 1 underwent one ESWT session for the GCM immediately after BTA injection and two consecutive ESWT sessions at weekly intervals. Ankle plantar flexor and the passive range of motion (PROM) of ankle dorsiflexion were measured by a modified Ashworth scale (MAS) before treatment and at 1 and 3 month(s) post-treatment. In group 1, the shear wave velocity (SWV) of GCM was measured. The PROM and MAS in group 1 and 2 before treatment significantly improved at 1 and 3 month(s) after treatment. The change in PROM was significantly different between the two groups at 1 and 3 month(s) after treatment. The SWV before treatment significantly decreased at 1 month and 3 months after treatment in group 1. Our study has shown that the combination of BTA injection and ESWT would be effective at controlling spasticity in children with spastic CP, with sustained improvement at 3 months after treatment.

Muscle Ultrasonographic Elastography in Children: Review of the Current Knowledge and Application

Ultrasonographic elastography is a relatively new imaging modality for the qualitative and quantitative assessments of tissue elasticity. While it has steadily gained use in adult clinical practice, including for liver diseases, breast cancer, thyroid pathologies, and muscle and tendon diseases, data on its paediatric application is still limited. Moreover, diagnosis of muscular diseases in children remains challenging. The gold standard methods, namely biopsy, electroneurography, and electromyography, are often limited owing to their invasive characteristics, possible contraindications, complications, and need for good cooperation, that is, a patient’s ability to perform certain tasks during the examination while withstanding discomfort, which is a significant problem especially in younger or uncooperative children. Genetic testing, which has broad diagnostic possibilities, often entails a high cost, which limits its application. Thus, a non-invasive, objective, repeatable, and accessible tool is needed to aid in both the diagnosis and monitoring of muscle pathologies. We believe that elastography may prove to be such a method. The aim of this review was to present the current knowledge on the use of muscle elastography in the paediatric population and information on the limitations of elastography in relation to examination protocols and factors for consideration in everyday practice and future studies.

A survey on various handover technologies in 5G network using the modular handover modules

Purpose

Fifth-generation (5G) networks play a significant role in handover methods. 5G wireless network is open, flexible and highly heterogeneous along with the overlay coverage and small cell deployments. Handover management is one of the main problems in the heterogeneous network. Also, handover satisfies the needs of ultra-reliable communications along with very high reliability and availability in 5G networks. Handover management deals with every active connection of a user’s device, which moves the connection between the user’s device and the counterparty from one network point to another. Thus, the handover decision determines the best access network and also decides whether the handover is performed or not. The purpose of this study is to review the handover technologies in 5G networks.

Design/methodology/approach

Using the categories of analysis, the existing techniques are divided into different techniques such as authentication-based techniques, blockchain-based techniques, software-defined-based techniques and radio access-based techniques. The survey is made by considering the methods such as used software, categorization of methods and used in the research works. Furthermore, the handover rate is considered for performance evaluation for the handover techniques in 5G. The drawbacks present in the existing review papers are elaborated in research gaps and issues division.

Findings

Through the detailed analysis and discussion, it can be summarized that the widely concerned evaluation metric for the performance evaluation is the handover rate. It is exploited that the handover rate within the range of 91%–99% is achieved by three research papers.

Originality/value

A survey on the various handover mechanisms in 5G networks is expected in this study. The research papers used in this survey are gathered from different sources such as Google Scholar and IEEE. Also, this survey suggests a further extension for the handover mechanism in 5G networks by considering various research gaps and issues.

Shear Wave Elastography for Assessment of Muscular Abnormalities Related to Systemic Sclerosis

RATIONALE AND OBJECTIVES

To assess muscular abnormalities related to systemic sclerosis (SSc) using shear wave elastography and correlate results with those of clinical tests.

MATERIALS AND METHODS

We evaluated 55 patients (mean age: 50.4 years; range: 18-88; 34 female) with SSc before treatment and choose muscle groups based on cutaneous involvement and functional impairment [forearms (9); thighs (41); thenar/hypothenar (5)]. We performed shear wave elastography in two orientations to access heterogeneity using virtual touch IQ and mean shear wave velocity values (SWV) and measured skin and fascia thickness. We compared SWVs to the modified Rodnan skin score (mRSS). Twenty-two healthy controls (mean age: 52.0; range: 19-88; 7 female) underwent the same protocol.

RESULTS

SWV pattern analysis (homogeneous vs heterogeneous) detected SSc with sensitivity/specificity/negative predictive value/positive predictive value0.79/0.81/0.91/0.62 in transverse and 0.75/0.18/0.91/0.56 in longitudinal orientation. In patients we found poor correlation between SWVs and mRSS but a cutoff of mRSSE = 20 separated them significantly (p < 0.01). Skin and muscle fascia were significantly thicker in patients vs. controls (p < 0.001).

CONCLUSION

SSc involves more than increased skin and fascial thickness which is not fully represented by mRSS. Elasticity differs in muscles with and without SSc. The former shows higher SWV and increased heterogeneity in transversal planes of muscular fibers.

Ultrasound shearwave elastography to characterize muscles of healthy and cerebral palsy children

Shear wave elastography (SWE) is an ultrasound technique to obtain soft tissue mechanical properties. The aim of this study was to establish the reliability of SWE in young children, define reference data on healthy ones and compare the shear modulus of healthy and spastic muscles from cerebral palsy (CP). The reproducibility is evaluated: at rest, on 7 children without any musculoskeletal pathology by 3 different operators, on 2 muscles: biceps brachii long head and medial gastrocnemius. The comparison study was made, on the same 2 muscles, at rest and under passive stretching, with a control group (29 healthy children), a spastic group (spastic muscles of 16 children from CP) and a non-spastic group (non-spastic muscles of 14 children from CP). The intra-operator reliability and inter-operator reliability, in terms of standard deviation, were 0.6 kPa (11.2% coefficient of variation (CV)) and 0.8 kPa (14.9% CV) for the biceps, respectively, and 0.4 kPa (11.5% CV) and 0.5 kPa (13.8% CV) for the gastrocnemius. At rest, no significant difference was found. Under passive stretching, the non-spastic CP biceps were significantly stiffer than the control ones (p = 0.033). Spastic gastrocnemius had a higher shear modulus than in the control muscles (p = 0.0003) or the non-spastic CP muscles (p = 0.017). CP stretched medial gastrocnemius presented an abnormally high shear moduli for 50% of patients.

Management of Muscle Spasticity in Children with Cerebral Palsy by Means of Extracorporeal Shockwave Therapy: A Systematic Review of the Literature

The purpose of this systematic review was to investigate the effectiveness of extracorporeal shockwave therapy for the management of muscle spasticity in children with cerebral palsy. An electronic database search was performed to identify studies relevant to the research question. Assessment of the quality of evidence in all relevant studies was performed with the help of the Oxford Center for Evidence-based Medicine guide. Four studies met our inclusion criteria for review: one was a low-quality randomized controlled clinical trial, two were individual case-control studies and one was a case series study. Reduction in muscle stiffness and improvement in joint range of motion were the outcomes in all of the selected studies that used extracorporeal shockwave therapy. However, considering the limited evidence provided by these studies, further research is needed to support the use of extracorporeal shockwave therapy in the management of muscle spasticity in children with cerebral palsy.

Biomechanical Evaluation of Intercostal Muscles in Healthy Children and Adolescent Idiopathic Scoliosis: A Preliminary Study

Spine deformity during adolescent idiopathic scoliosis can induce a rib-cage deformity. This bone deformity can have direct consequences on the chest-wall muscles, including intercostal muscles, leading to respiratory impairments in individuals with severe cases. The aim of this study was to determine whether shear-wave elastography can be used to measure intercostal-muscle shear-wave speed (SWS) in healthy children and those with adolescent idiopathic scoliosis (AIS). Nineteen healthy participants and 16 with AIS took part. SWS measurements were taken by three operators, twice each. Average SWS was 2.3 ± 0.4 m/s, and inter-operator reproducibility was 0.2 m/s. SWS was significantly higher during apnea than in normal breathing (p < 0.01) in both groups. No significant difference was observed between groups in apnea or in normal breathing. Characterization of the intercostal muscles by ultrasound elastography is therefore feasible and reliable for children and adolescents with and without scoliosis.

Use of Shear Wave Elastography for Quantitative Assessment of Muscle Stiffness After Botulinum Toxin Injection in Children With Cerebral Palsy

OBJECTIVES

This study aimed to investigate the stiffness of the gastrocnemius (GC) muscle with acoustic radiation force impulse (ARFI) elastography after botulinum toxin-A (BTX-A) injection in children with spastic cerebral palsy (CP) and to examine the relationship between elastographic and clinical parameters.

METHODS

This prospective randomized single-blind controlled clinical study included 49 lower extremities of 33 children with spastic CP. They were randomized into 2 groups: group 1 (n = 25 extremities in 17 children) received BTX-A injection and a home-based exercise program; group 2 (n = 24 extremities in 16 children) received only a home-based exercise program. Patients were evaluated in pretreatment and posttreatment periods in the first and third months with ARFI elastography, the Modified Ashworth Scale, Modified Tardieu Scale, Pediatric Functional Independence Measure, Gross Motor Function Classification System, and goniometric range of motion measurement of the ankle.

RESULTS

A statistically significant difference was found in elastography of the GC muscle in group 1 only at the first month after treatment (P < .05). No statistical difference was found in elastography of the GC after treatment in group 2. According to the Modified Ashworth Scale, Modified Tardieu Scale, and ankle passive range of motion, group 1 showed significant improvements after treatment (P < .05). Also, there was a significant correlation between these clinical parameters and elastographic measurements (P < .05).

CONCLUSIONS

According to the results of this study, the measurements from ARFI elastography combined with clinical parameters might be useful for evaluation of spasticity after BTX-A treatment in children with CP. Also, they might be useful in distinguishing patients who will benefit clinically, especially in the early stages of treatment.

Usability and Pitfalls of Shear-Wave Elastography for Evaluation of Muscle Quality and Its Potential in Assessing Sarcopenia: A Review

Sarcopenia is age-related progressive and generalized loss of skeletal muscle mass and strength. Its prevalence is rising, which poses a burden for society because it increases disability and dependency and therefore raises health care costs. Muscle mass quality, however-an essential part of sarcopenia-is not easily diagnosable yet. Recent interest has risen for ultrasonographic evaluation of muscle. This review introduces muscle elastography as a possible, easy and cheap tool to evaluate qualitative muscle parameters. Basic principles of muscle elastography are described, as well as different elastography techniques and some technical considerations. Furthermore, a proposal for practical guidelines is offered and factors influencing muscle stiffness are highlighted.

Evidence-Based Practice in Rehabilitation of Myasthenia Gravis. A Systematic Review of the Literature

Myasthenia gravis is a rare neuromuscular disorder characterized by muscle weakness and fatigue. This review analyzes the most recent evidence regarding the effectiveness and safety of different rehabilitative approaches to the disease. The review was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 365 articles were found in the main scientific databases. Applying the inclusion/exclusion criteria, 11 studies were admitted to the final phase of the review. Three different rehabilitative approaches were identified: physical training, respiratory training, and balance training. All rehabilitative modalities contributed to enhancing functional outcomes, reducing fatigue, and improving quality of life, but currently none can be recommended over another for the lack of cross-comparative studies. The included studies showed methodological quality from low to fair. Despite the range of rehabilitative interventions available, there is a lack of high-quality evidence. However, this review suggests that a multidisciplinary rehabilitation approach should be recommended to people with myasthenia gravis, and above all, for those with mild to moderate symptomatology.

The utility of shear wave elastography in the evaluation of muscle stiffness in patients with cerebral palsy after botulinum toxin A injection

PURPOSE

The first aim of this study was to evaluate changes in the stiffness of the medial gastrocnemius muscle (GM) after a botulinum toxin A (BoNT-A) injection in children with cerebral palsy (CP) using shear wave elastography (SWE). We also wanted to investigate the usability of SWE for evaluating spasticity in a clinical setting. The second aim of this study was to show how treatment of the gastrocnemius muscle spasticity caused a change in the elasticity of the anterior tibial (TA) muscle.

METHODS

Twenty-four pediatric patients diagnosed with a spastic type of CP, who were scheduled to receive a BoNT-A injection in the gastrocnemius muscle, were included in the study. There was a total of 43 lower extremities to evaluate, and muscle stiffness was measured before the injection and a month post injection using SWE. The physiatrist evaluated muscle spasticity using the Modified Ashworth Scale (MAS) and the Modified Tardieu Scale at about the same time.

RESULTS

SWE values of the GM (pre-BoNT-A: 45.9 ± 6.5 kPa, post-BoNT-A: 25.0 ± 5.7 kPa) decreased significantly post BoNT-A injection (P < 0.01). SWE measurements of the GM had positive correlations with MAS, V1X, V3X, and R2-R1 (P < 0.01); and negative correlations with R2 and R1 (P < 0.05). SWE values of the TA muscle (pre: 36.9 ± 7.9 kPa, post: 28.4 ± 5.2 kPa) decreased significantly (P < 0.01).

CONCLUSION

Quantitative measurement of muscle stiffness using SWE may provide important information for the evaluation of spasticity and treatment efficiency in pediatric CP patients.

Evidence-Based Physical Therapy for Individuals with Rett Syndrome: A Systematic Review

Rett syndrome is a rare genetic disorder that affects brain development and causes severe mental and physical disability. This systematic review analyzes the most recent evidence concerning the role of physical therapy in the management of individuals with Rett syndrome. The review was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. A total of 17319 studies were found in the main scientific databases. Applying the inclusion/exclusion criteria, 22 studies were admitted to the final phase of the review. Level of evidence of the included studies was assessed using the Oxford Centre for Evidence-Based Medicine—Levels of Evidence guide. Nine approaches to physical therapy for patients with Rett syndrome were identified: applied behavior analysis, conductive education, environmental enrichment, traditional physiotherapy with or without aids, hydrotherapy, treadmill, music therapy, computerized systems, and sensory-based treatment. It has been reported that patients had clinically benefited from the analysed approaches despite the fact that they did not have strong research evidence. According to the results, a multimodal individualized physical therapy program should be regularly recommended to patients with Rett syndrome in order to preserve autonomy and to improve quality of life. However, more high-quality studies are needed to confirm these findings.