Bipolar Release Research Articles

Heterogeneous presynaptic receptive fields contribute to directional tuning in starburst amacrine cells.

The processing of visual information by retinal starburst amacrine cells (SACs) involves transforming excitatory input from bipolar cells (BCs) into directional calcium output. While previous studies have suggested that an asymmetry in the kinetic properties of BCs along the soma-dendritic axes of the postsynaptic cell could enhance directional tuning at the level of individual branches, it remains unclear whether biologically relevant presynaptic kinetics contribute to direction selectivity (DS) when visual stimulation engages the entire dendritic tree. To address this question, we built multicompartmental models of the bipolar-SAC circuit and trained them to boost directional tuning. We report that despite significant dendritic crosstalk and dissimilar directional preferences along the dendrites that occur during whole-cell stimulation, the rules that guide BC kinetics leading to optimal DS are similar to the single-dendrite condition. To correlate model predictions to empirical findings, we utilized two-photon glutamate imaging to study the dynamics of bipolar release onto ON- and OFF-starburst dendrites in the murine retina. We reveal diverse presynaptic dynamics in response to motion in both BC populations; algorithms trained on the experimental data suggested that the differences in the temporal release kinetics are likely to correspond to heterogeneous receptive field properties among the different BC types, including the spatial extent of the center and surround components. In addition, we demonstrate that circuit architecture composed of presynaptic units with experimentally recorded dynamics could enhance directional drive but not to levels that replicate empirical findings, suggesting other DS mechanisms are required to explain SAC function. Our study provides new insights into the complex mechanisms underlying DS in retinal processing and highlights the potential contribution of presynaptic kinetics to the computation of visual information by SACs.

Heterogeneous presynaptic receptive fields contribute to directional tuning in starburst amacrine cells

The processing of visual information by retinal starburst amacrine cells (SACs) involves transforming excitatory input from bipolar cells (BCs) into directional calcium output. While previous studies have suggested that an asymmetry in the kinetic properties of BCs along the soma-dendritic axes of the postsynaptic cell could enhance directional tuning at the level of individual branches, it remains unclear whether biologically relevant presynaptic kinetics contribute to direction selectivity (DS) when visual stimulation engages the entire dendritic tree. To address this question, we built multicompartmental models of the bipolar–SAC circuit and trained them to boost directional tuning. We report that despite significant dendritic crosstalk and dissimilar directional preferences along the dendrites that occur during whole-cell stimulation, the rules that guide BC kinetics leading to optimal DS are similar to the single-dendrite condition. To correlate model predictions to empirical findings, we utilized two-photon glutamate imaging to study the dynamics of bipolar release onto ON- and OFF-starburst dendrites in the murine retina. We reveal diverse presynaptic dynamics in response to motion in both BC populations; algorithms trained on the experimental data suggested that the differences in the temporal release kinetics are likely to correspond to heterogeneous receptive field properties among the different BC types, including the spatial extent of the center and surround components. In addition, we demonstrate that circuit architecture composed of presynaptic units with experimentally recorded dynamics could enhance directional drive but not to levels that replicate empirical findings, suggesting other DS mechanisms are required to explain SAC function. Our study provides new insights into the complex mechanisms underlying DS in retinal processing and highlights the potential contribution of presynaptic kinetics to the computation of visual information by SACs.

Clinical Results after Release of Sternocleidomastoid Muscle Surgery for Neglected Congenital Muscular Torticollis-Unipolar vs. Bipolar Release Surgery.

Although the surgical release of the sternocleidomastoid muscle (SCM) is required for residual congenital muscular torticollis (CMT), the surgical outcomes between bipolar and unipolar SCM release remained unclear. The purpose of the present study was to assess surgical outcomes after bipolar and unipolar release of SCM in adolescent/adult patients with neglected CMT. Twenty-one consecutive adolescent/adult patients with neglected CMT who underwent surgical treatment were enrolled. Clinical and radiographic outcomes were evaluated at preoperative and final follow-up. The bipolar release of SCM was performed in 3 patients (B group; males, n = 1, females, n = 2) and the unipolar release of SCM in 18 patients (U group; males, n = 6, females, n = 12). The mean age at surgery was 40.0 ± 17.0 years in Group B, and that was 32.3 ± 13.1 years in Group U (p = 0.47). The mean follow-up period was 16.0 ± 5.7 months in Group B and 10.4 ± 7.6 months in Group U (p = 0.22). Cervicomandibular angle correction rates were comparable at 75.4 ± 2.4% for the B group and 73.1 ± 11.7% for the U group (p = 0.62). There was no significant difference in clinical outcome according to the modified Cheng and Tang score between the two groups (p = 0.89). No major complications arose, although one patient exhibited a transient neurological deficit of the greater auricular nerve, and one patient developed a hematoma in the B group. The unipolar SCM release appeared to be a non-inferiority and less invasive procedure, minimizing surgical scars and avoiding potential auricular nerve damage in adolescent/adult patients with neglected CMT.

Congenital muscular torticollis in young adultpatient: A neglected case.The efficiency of bipolar release

Congenital muscular torticollis (CMT) is a common postural deformity evident shortly after birth characterized by ipsilateral cervical lateral flexion and contralateral cervical rotation due to unilateral shortening of the sternocleidomastoid muscle. Untreated, the sequelae include facial asymmetry, tight bands, ophthalmic abnormalities, and altered neck posture. To report a neglected CMT in 17-year-old female treated surgically by bipolar muscle release technic. The surgery was made via a double incision above the clavicular and mastoid with the liberation of the fibrous bands followed by intensive physiotherapy program. The patient was very satisfied after management. Neglected CMT adult’s patients can benefit from surgical treatment. Bipolar release is an adequate and complication-free method with postoperative physiotherapy program.

Congenital muscular torticollis in young adultpatient: A neglected case.The efficiency of bipolar release

Congenital muscular torticollis in young adultpatient: A neglected case.The efficiency of bipolar release

Delayed Correction of Congenital Torticollis with Modified Bipolar Release

Delayed Correction of Congenital Torticollis with Modified Bipolar Release

Prognostic Factors in Recurrent Congenital Muscular Torticollis.

Introduction:Congenital muscular torticollis (CMT), primarily resulting from unilateral shortening and fibrosis of the sternocleidomastoid muscle. One of the common surgical complications is recurrent deformity. However, the associations between unipolar or bipolar release, age of the patient, and the recurrence of the disease are unclear. Therefore, the purpose of this study was to evaluate the factors associated with recurrence after surgery.Materials and Methods:A retrospective review was performed in 47 patients who were diagnosed with CMT and had been treated surgically with unipolar or bipolar release between January 2007 and December 2015. Demographic data (sex, sides, surgical technique, age at time of surgery, period of follow-up, complications and recurrence) were recorded.Results:Forty-seven patients with an average age of 8.7 years old at time of surgery. Twenty-six patients had right-sided muscular torticollis, while 21 had left-sided. The average follow-up time was 2 years (range, 2–4 years). The average age of unipolar release was 8.8 years old (range, 218 years old), while the average age of bipolar release was 8.7 years old (range, 2–13 years old). Recurrence occurred in 11 patients (9 in unipolar and 2 in bipolar release). Sex, side of deformity, type of surgery and age at time of surgery showed no statistically significant as a factor for recurrence rate, however recurrence of unipolar more than bipolar surgery was nearly two times revealing clinical significance.Conclusions:Sex, side of deformity, type of surgery and age at time of surgery were not associated with the recurrence deformity.

Reversal of Degenerative Changes in Cervical Spine Following Bipolar Release in a Neglected Case of Congenital Muscular Torticollis: A Case Report

Background & Importance: Congenital Muscular Torticollis (CMT) is a common cause of torticollis in children. Despite the easy diagnosis, rare cases may be neglected and untreated during the management of the patients, which can not only impose cosmetic problems for them but also affect the cervical spine with accelerated degeneration. Most patients with CMT can be managed non-surgically with medical and physical therapies but surgery is indicated in some cases when non-surgical attempts are unsuccessful. Case Presentation: Herein, we are reporting a 16-year-old female with neglected CMT, and neck pain secondary to severe degenerative changes. We believe that neglected and untreated CMT cases may present with accelerated spine degeneration and surgical intervention should be considered promptly to reverse this process. Conclusion: Surgical intervention not only produces good cosmetic results but also reverses the degeneration process and protects the patient from disabling deformities later in life.

Cutting of Origin and Insertion of Sternocleidomastoid Muscle for Treatment of Torticollis

Abstract Background: Congenital Muscular Torticollis (CMT), caused by fibromatosis within the Sternocleidomastoid Muscle (SCM), cause cosmetic and functional problems which in turn can have an adverse impact on these patients in their adoles-cence and adulthood. Several operation have been used to release the SCM and the best technique is still controversial. Aim of Study: We assessed the surgical results of bipolar release in 10 adult patients with uncorrected congenital muscular torticollis and more than 12 months of follow-up. Patients and Methods: These patients underwent a bipolar release of the SCM and were retrospectively analyzed. The mean follow-up period was 14.9 months (range, 12-30). The mean age at time of surgery was 21 years (range, 18-24). Results: The modified Lee's scoring system indicated excellent results in 3 (30%) patients, good in 5 (50%), and fair in 2 (20%) at the last follow-up after surgery. The im-provements in neck movement and head tilt were statistically significant (p<0.05). The global satisfaction rating scale was 93.7% (range, 90-100). No significant permanent complications occurred. Conclusion: Bipolar release of the SCM is a safe and reliable technique for the treatment of CMT in adults.

SURGICAL TREATMENT OF CONGENITAL TORTICOLLIS, AT THE SHRINERS HOSPITAL, MEXICO CITY

ABSTRACT Objective: This study aims to evaluate the outcome of surgical treatment of congenital torticollis in our hospital. Methods: We collected the medical records of all patients diagnosed with congenital torticollis in the last 3 years at Shriners Hospital, Mexico City. The cases of congenital torticollis treated with surgery were selected and we evaluated the type of surgical technique, bleeding, time of surgery and complications, as well as the associated diagnoses of hip dysplasia. Results: We found 11 patients, of whom 7 met the inclusion criteria. Three women and four men with mean age of 10.7 years, five of whom had right, and two left side affections. All were surgically treated, five with unipolar and two with bipolar release. The surgery time was similar in both techniques and no complications were found in any of the groups. In two cases there were associated diagnoses, Klippel-Feil syndrome and congenital talipes equinovarus (CTEV) in one and psychomotor retardation in another. No association was found with hip dysplasia. All patients had improved range of movement and head tilt. There were no complications related to the surgical procedure or need for reintervention in our patients. Conclusions: Surgical treatment of congenital torticollis by uni- or bipolar release is an effective and safe method for these patients, presenting aesthetic and functional benefits.

Congenital muscular torticollis: Use of gaze angle and translational deformity in assessment of facial asymmetry.

Background:Assessment of facial asymmetry is challenging in torticollis deformity. Neck tilt in toroticollis is associated with deviation of horizontal ocular gaze and translation of neck from the midline. These deviations can be assessed clinically and can be used as surrogate marker for facial asymmetry.Materials and Methods:Thirty five children with congenital muscular torticollis (CMT) were classified into three grades of severity based on the new clinical score. The parameters included in the scoring system included rotational deficit, side flexion deficit, gaze angle (GA), and translational deformity (TD). Seven children had Grade I (mild), 18 had Grade II (moderate), and 10 had Grade III (severe) CMT. There were 21 girls and 14 boys with a mean age of 8.46 years (range 3–16 years). Twenty two children underwent a bipolar release, and 13 had unipolar surgery. Facial asymmetry (FA) signs were noted and based on GA and TD; all children had a deviation from the neutral angles (GA of 90° and 0 mm translation from the midsterna plumb line were considered neutral angle). The final outcome was based on the modified Cheng and Tang Score.Results:The mean GA in Grade I, II, and III improved from 81.71 to 90, 72.77 to 89.16, and 66.60 to 88, respectively (Chi-square P < 0.0001). The TD improved from 15 mm to 0 mm, 25.83 mm to 3.05 mm, and 36.6 mm to 6 mm in Grade I, II, and III, respectively (Chi-square P < 0.05). The rotational and side flexion deficits also improved across all grades of severity but were not statistically significant (P < 0.911 and P < 0.04). Twenty four children had an excellent outcome with complete correction of their GA and TD. Four children with Grade II CMT and seven children with Grade III who had a residual translation of 5 mm or more and GA less than neutral horizontal had a good outcome. No child had problems with scar cosmesis or prominent lateral bands, and there was no recurrence of deformity at a mean followup of 28 months (range 24–32 months).Conclusion:The GA and TD can be used to assess FA in torticollis management and significant improvement can be expected even in severe cases.

Functional and Aesthetic Recovery of Congenital Muscular Torticollis with Intramuscular Stromal Vascular Fraction Enriched Fat Grafting

Congenital muscular torticollis is a well-known pathological condition caused by the contracture and shortening of the sternocleidomastoid muscle. This condition is manifested by a neck postural deformity often accompanied by some kind of facial asymmetry. Once diagnosed, treatment by early physiotherapy is generally successful in a high percentage of patients if performed during the first year of life. Later, especially after the fourth year, conservative treatment is usually far less effective, and surgical techniques remain the only way to improve neck contour and function. The author reports two cases of adult patients affected by this condition and successfully treated with a novel therapeutic approach consisting of percutaneous myotomies and intramuscular cell-assisted fat grafting.Two cases of adult patients diagnosed with congenital muscular torticollis were analyzed after treatment with percutaneous myotomies and intramuscular fat grafting. The first patient had a history of unsuccessful treatment in infancy with bipolar release of the sternocleidomastoid muscle and was treated with two sessions of fat grafting. The second patient had a history of neglected torticollis and was treated with a single session of cell-assisted fat grafting. In both cases, facial asymmetries were simultaneously treated with the same fat grafting protocol used to treat the muscle. Improvements in muscle function and in face and neck contours were extremely good and stable in both patients. The postoperative course for both patients was uneventful and with a very short and easy recovery when compared with the techniques described to date.Neglected congenital muscular torticollis in adults, or in patients who have not responded adequately to surgical treatment, has been treated safely with percutaneous myotomies and intramuscular fat grafting. The benefit is a scarless technique that provides simultaneous recovery of neck aesthetics and muscle function together with a very short recovery time. Further studies must be conducted to properly evaluate the long-term safety and convenience of cell enrichment to achieve better and long-lasting results.

A Comparison of Outcome of Age at Time Surgery between Younger and Older than 8 Years Old in Children with Congenital Muscular Torticollis

Objective: Comparing results between surgical techniques and age at the time of surgery, and the effectiveness of surgical release unipolar or bipolar or both the sternocleidomastoid muscle for congenital muscular torticollis. Methods: This study was a retrospective study of 44 cases with sternocleidomastoid muscle. Children had operated release at mean age: 6.2 years old, at Pediatric Orthopaedic Department of National Hospital for Padiatrics between October 2006 and December 2015. Preoperative assessment included the age of child at presentation, any previous history of swelling in the neck in infancy. The degree of neck tilt and range of motion of the neck, flexion and limitation of rotation were recorded. The ultrasound, measure cervico-mandibular angle (CMA). Children had performed operation by Unipolar or Bipolar release. Operative results were according to assess by the score of Cheng et al. Results: The patients were divided into two Variants. Variant 1 (patients Younger than 8 Years) had 33 Patients and Variant 2 (patients Older than 8 Years) had 11 patients. Sex: Female: 18, Male 26; Mean age: 6.2 years old; Affect side: Right: 31, Left: 13; Operative Methods: Unipolar: 33, Bipolar: 11; Follow-up: 55.0 months (24-81). Improvement of limitation of Lateral Bending in Variant 1/Variant 2: 95.2%/63.2%; Improvement of Limitation of Rotation in Variant 1/Variant 2: 63.9%/52.7%; Improvement of Angle of Head Tilt in Variant 1/Variant 2: 86.6%/66.3%. Accepted result (Excellent Good): 30/33 (90.9% in Variant 1, 8/11 (72.7%) in Variant 2. Conclusion: The diagnostic and evaluation of CMT requires a systematic team approach with members from fields of radiology, physiotherapy, craniofacial surgery, orthopaedics, neurosurgery and ophthalmology. The patients should be performed surgery for neck muscle release only if torticollis persists after the age of one year. The rehabilitation should be performed soon after surgery.

Adult Patients with Congenital Muscular Torticollis Treated with Bipolar Release: Report of 31 Cases.

ObjectiveWe assessed the surgical results of bipolar release in 31 adult patients with uncorrected congenital muscular torticollis (CMT) and more than 12 months of follow-up.MethodsThirty-one patients underwent a bipolar release of the sternocleidomastoid muscle (SCM) and were retrospectively analyzed. The mean follow-up period was 14.9 months (range, 12–30). The mean age at time of surgery was 30.3 years (range, 20–54). Patients were evaluated with a modified Lee’s scoring system, cervicomandibular angle (CMA) measurement, and a global satisfaction rating scale using patient self-reporting.ResultsThe modified Lee’s scoring system indicated excellent results in 4 (12.9%) patients, good in 18 (58.1%), and fair in 9 (29.0%) at the last follow-up after surgery. The improvements in neck movement and head tilt were statistically significant (p<0.05). The preoperative mean CMA was 15.4° (range, 5.4–29.0), which was reduced to a mean of CMA of 6.3° (range, 0–25) after surgery (p<0.05). The global satisfaction rating scale was 93.7% (range, 90–100). A transient sensory deficit on the ipsilateral lower ear lobe was noted in three cases. No significant permanent complications occurred.ConclusionBipolar release of the SCM is a safe and reliable technique for the treatment of CMT in adults.

Management of neglected cases of congenital muscular torticollis with bipolar release

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Congenital muscular torticollis (CMT) is the third most common congenital musculoskeletal anomaly in children. After the age of one year functional and cosmetic benefits require corrective surgery. Neglected congenital torticollis is commoner in developing countries. The purpose of this study was to evaluate the results of bipolar release in this age group&lt;span lang="EN-IN"&gt;.&lt;/span&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; 16 cases were operated on for&lt;strong&gt; &lt;/strong&gt;neglected congenital muscular torticollis. Inclusion criteria&lt;strong&gt; &lt;/strong&gt;included age of more than ten years, absence of any previous&lt;strong&gt; &lt;/strong&gt;surgery, and absence of any known pathology. Inferior release&lt;strong&gt; &lt;/strong&gt;was done through an incision 1 cm above the medial&lt;strong&gt; &lt;/strong&gt;third of the clavicle. The clavicular head was released&lt;strong&gt; &lt;/strong&gt;completely while the sternal head was lengthened by&lt;strong&gt; &lt;/strong&gt;z-plasty. The mastoid head was released though an incision&lt;strong&gt; &lt;/strong&gt;just below the tip of the mastoid process. The postoperative management included physiotherapy with halter traction. Neck ROM, head tilt, craniofacial asymmetry were assessed.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; Excellent results were noted in four patients, good in eight, fair in two, and poor in two&lt;span lang="EN-IN"&gt;. &lt;/span&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; We believe that bipolar release is a very viable option for correcting neglected CMT as it brought about both functional improvement as well as improvement in cosmesis, resulting in improved quality of life&lt;span lang="EN-IN"&gt;.&lt;/span&gt;&lt;/p&gt;

Neglected case of congenital muscular torticollis treated with Bipolar release. A case Report

Neglected congenital muscular torticollis CMT is a common presentation in developing countries like India. The primary concern of the patients is cosmetic. There is only a few case reports that indicating efficacy of surgery for neglected case of CMT. We report a case of neglected CMT in an 18-year-old female patient which was successfully managed at the institute. We performed a bipolar resection with z plasty lengthening of the sternocleidomastoid muscle SCM. After surgery the range of neck movement and head tilt improved. We emphasize that surgical management of adult patients with neglected congenital muscular torticollis is a treatment option yielding good cosmetic and functional outcome.nbsp

Lower Pole Release in Congenital Muscular Torticollis – Retrospective Analysis of Outcomes in 15 Cases

Abstract Congenital muscular torticollis is a common congenital problem. It is considered to be amenable to treatment which may be conservative or surgical. There are as yet no fixed guidelines as to the methodology or the timing of treatment. It is certainly advised to be prudent in selecting the appropriate treatment which should neither be too conservative nor over-invasive. We are reporting a series of 15 cases in which we did a unipolar release of the sternocleidomastoid muscle at the lower attachment. Retrospective analysis of 15 consecutive patients is done. During the postoperative period the parents were advised to regularly continue with the stretching exercises, focus on activities on the opposite side of the face and use a semi-rigid cervical collar, specially designed for active correction of these cases. We got very satisfactory postoperative results in most of our patients except one who had resistant deformity due to advanced age. In conclusion we would like to bring the focus back to unipolar release which is shifting unduly in favour of a bipolar release. This would also reduce the chances of the complication of accessory nerve injury. We have used the scoring system developed by Cheng et al and modifi ed by Shim in which the present cases showed improvement of 7 points with p-value of less than 0.0001

Congenital Muscular Torticollis and Positional Plagiocephaly

Congenital Muscular Torticollis and Positional Plagiocephaly

Congenital Muscular Torticollis and Positional Plagiocephaly

On the basis of observational studies, child health practitioners in primary care settings should consider the diagnosis of congenital muscular torticollis (CMT)in infants with risk factors from birth history for intrauterine malpositioning or constraint (C). On the basis of observational studies, CMT is often associated with other conditions, including positional plagiocephaly and gross motor delays from weakened truncal muscles and/or lack of head control in early infancy (C). On the basis of observational studies, child health practitioners should counsel parents that infants should be on their stomachs frequently whenever they are awake and under direct adult supervision to develop their prone motor skills (C). On the basis of consensus, early identification of CMT(with or without positional plagiocephaly) and prompt referral to a physical therapist experienced in the treatment of CMT should be considered to avoid more costly or invasive treatments, such as cranial orthoses or surgery (D).

Outcome of bipolar release of the sternocleidomastoid muscle in neglected congenital muscular torticollis

Purpose: Neglected congenital muscular torticollis (CMT) is a common presentation in our country, which poses largely a cosmetic disability. Surgical correction is recommended for patients with late reporting cases. The aim of this study is to evaluate the efficacy of surgical release of CMT in neglected cases. Materials and Methods: In the present retrospective case series, eleven patients of neglected CMT were treated by a modified Ferkel's release which comprising a bipolar release of the sternocleidomastoid muscle with Z-lengthening. The age at operation ranged from 4 to 18 years (mean 8.3 years). Post-operative protocol included head halter traction for 6 weeks and physiotherapy. Results were evaluated by the scoring system of Lee et al . Results: At an average follow-up of 4.4 years (range: 2-8.6 years), excellent results were noted in 8 patients (72.7%) and good in 3 (27.2%). In this study, significant improvement of neck motion, head tilt, chin deviation and cosmesis were observed with surgical treatment. There were no surgery-related complications or recurrences occurred in any of these patients. Conclusions: Patients with neglected CMT can benefit from surgical treatment and bipolar release is an effective and complication-free method for such patients.