scholarly journals Optimal duration of postoperative helmet therapy following endoscopic strip craniectomy for sagittal craniosynostosis

2018 ◽  
Vol 22 (6) ◽  
pp. 610-615 ◽  
Author(s):  
Rajiv R. Iyer ◽  
Xiaobu Ye ◽  
Qiuyu Jin ◽  
Yao Lu ◽  
Luckmini Liyanage ◽  
...  
Keyword(s):  
Peak Level ◽  
Multivariate Regression Analysis ◽  
Final Outcome ◽  
Sagittal Synostosis ◽  
Sagittal Craniosynostosis ◽  
Time Period ◽  
Helmet Therapy ◽  
Age At Surgery ◽  
Strip Craniectomy

OBJECTIVEMany infants with sagittal craniosynostosis undergo effective surgical correction with endoscopic strip craniectomy (ESC) and postoperative helmet therapy (PHT). While PHT is essential to achieving optimal cosmesis following ESC, there has been little comprehensive analysis of the ideal PHT duration needed to attain this goal.METHODSThe authors retrospectively reviewed the charts of infants undergoing ESC and PHT for sagittal synostosis at our institution between 2008 and 2015. Data collected included age at surgery, follow-up duration, and PHT duration. Cephalic index (CI) was evaluated preoperatively (CIpre), at its peak level (CImax), at termination of helmet therapy (CIoff), and at last follow-up (CIfinal). A multivariate regression analysis was performed to determine factors influencing CIfinal.RESULTSThirty-one patients (27 male, 4 female) were treated in the studied time period. The median age at surgery was 2.7 months (range 1.6 to 3.2) and the median duration of PHT was 10.4 months (range 8.4 to 14.4). The mean CImax was 0.83 (SD 0.01), which was attained an average of 8.4 months (SD 1.2) following PHT initiation. At last follow-up, there was an average retraction of CIfinal among all patients to 0.78 (SD 0.01). Longer helmet duration after achieving CImax did not correlate with higher CIfinal values. While CImax was a significant predictor of CIfinal, neither age at surgery nor CIpre were found to be predictive of final outcome.CONCLUSIONSPatients undergoing ESC and PHT for sagittal synostosis reach a peak CI around 7 to 9 months after surgery. PHT beyond CImax does not improve final anthropometric outcomes. CIfinal is significantly dependent on CImax, but not on age, nor CIpre. These results imply that helmet removal at CImax may be appropriate for ESC patients, while helmeting beyond the peak does not change final outcome.

scholarly journals Regression of cephalic index following endoscopic repair of sagittal synostosis

2019 ◽  
Vol 23 (1) ◽  
pp. 54-60
Author(s):  
Nicholas A. Pickersgill ◽  
Gary B. Skolnick ◽  
Sybill D. Naidoo ◽  
Matthew D. Smyth ◽  
Kamlesh B. Patel
Keyword(s):  
Time Course ◽  
Strong Positive Correlation ◽  
Cephalic Index ◽  
Sagittal Synostosis ◽  
Endoscopic Repair ◽  
Future Studies ◽  
Helmet Therapy ◽  
Significant Regression ◽  
Strip Craniectomy

OBJECTIVEMetrics used to quantify preoperative severity and postoperative outcomes for patients with sagittal synostosis include cephalic index (CI), the well-known standard, and the recently described adjusted cephalic index (aCI), which accounts for altered euryon location. This study tracks the time course of these measures following endoscopic repair with orthotic helmet therapy. The authors hypothesize that CI and aCI show significant regression following endoscope-assisted repair.METHODSCT scans or 3D photographs of patients with nonsyndromic sagittal synostosis treated before 6 months of age by endoscope-assisted strip craniectomy and postoperative helmet therapy (n = 41) were reviewed retrospectively at three time points (preoperatively, 0–2 months after helmeting, and > 24 months postoperatively). The CI and aCI were measured at each time point.RESULTSMean CI and aCI increased from 71.8 to 78.2 and 62.7 to 72.4, respectively, during helmet treatment (p < 0.001). At final follow-up, mean CI and aCI had regressed significantly from 78.2 to 76.5 and 72.4 to 69.7, respectively (p < 0.001). The CI regressed in 33 of 41 cases (80%) and aCI in 39 of 41 cases (95%). The authors observed a mean loss of 31% of improvement in aCI achieved through treatment. A strong, positive correlation existed between CI and aCI (R = 0.88).CONCLUSIONSRegression following endoscope-assisted strip craniectomy with postoperative helmet therapy commonly occurs in patients with sagittal synostosis. Future studies are required to determine whether duration of helmet therapy or modifications in helmet design affect regression.

Endoscopically assisted versus open repair of sagittal craniosynostosis: the St. Louis Children's Hospital experience

2011 ◽  
Vol 8 (2) ◽  
pp. 165-170 ◽  
Author(s):  
Manish N. Shah ◽  
Alex A. Kane ◽  
J. Dayne Petersen ◽  
Albert S. Woo ◽  
Sybill D. Naidoo ◽  
...  
Keyword(s):  
Length Of Stay ◽  
Blood Loss ◽  
Open Surgery ◽  
Operating Time ◽  
Endoscopic Procedure ◽  
Sagittal Craniosynostosis ◽  
Helmet Therapy ◽  
Age At Surgery ◽  
The Mean ◽  
Strip Craniectomy

Object This study investigated the differences in effectiveness and morbidity between endoscopically assisted wide-vertex strip craniectomy with barrel-stave osteotomies and postoperative helmet therapy versus open calvarial vault reconstruction without helmet therapy for sagittal craniosynostosis. Methods Between 2003 and 2010, the authors prospectively observed 89 children less than 12 months old who were surgically treated for a diagnosis of isolated sagittal synostosis. The endoscopic procedure was offered starting in 2006. The data associated with length of stay, blood loss, transfusion rates, operating times, and cephalic indices were reviewed. Results There were 47 endoscopically treated patients with a mean age at surgery of 3.6 months and 42 patients with open-vault reconstruction whose mean age at surgery was 6.8 months. The mean follow-up time was 13 months for endoscopic versus 25 months for open procedures. The mean operating time for the endoscopic procedure was 88 minutes, versus 179 minutes for the open surgery. The mean blood loss was 29 ml for endoscopic versus 218 ml for open procedures. Three endoscopically treated cases (6.4%) underwent transfusion, whereas all patients with open procedures underwent transfusion, with a mean of 1.6 transfusions per patient. The mean length of stay was 1.2 days for endoscopic and 3.9 days for open procedures. Of endoscopically treated patients completing helmet therapy, the mean duration for helmet therapy was 8.7 months. The mean pre- and postoperative cephalic indices for endoscopic procedures were 68% and 76% at 13 months postoperatively, versus 68% and 77% at 25 months postoperatively for open surgery. Conclusions Endoscopically assisted strip craniectomy offers a safe and effective treatment for sagittal craniosynostosis that is comparable in outcome to calvarial vault reconstruction, with no increase in morbidity and a shorter length of stay.

scholarly journals Neosuture formation after endoscope-assisted craniosynostosis repair

2016 ◽  
Vol 18 (2) ◽  
pp. 196-200 ◽  
Author(s):  
Afshin Salehi ◽  
Katherine Ott ◽  
Gary B. Skolnick ◽  
Dennis C. Nguyen ◽  
Sybill D. Naidoo ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Head Width ◽  
Long Term Outcomes ◽  
Sagittal Synostosis ◽  
Helmet Therapy ◽  
Age At Surgery ◽  
Significant Difference ◽  
Ct Data ◽  
Strip Craniectomy

OBJECTIVE The goal of this study was to identify the rate of neosuture formation in patients with craniosynostosis treated with endoscope-assisted strip craniectomy and investigate whether neosuture formation in sagittal craniosynostosis has an effect on postoperative calvarial shape. METHODS The authors retrospectively reviewed 166 cases of nonsyndromic craniosynostosis that underwent endoscope-assisted repair between 2006 and 2014. Preoperative and 1-year postoperative head CT scans were evaluated, and the rate of neosuture formation was calculated. Three-dimensional reconstructions of the CT data were used to measure cephalic index (CI) (ratio of head width and length) of patients with sagittal synostosis. Regression analysis was used to calculate significant differences between patients with and without neosuture accounting for age at surgery and preoperative CI. RESULTS Review of 96 patients revealed that some degree of neosuture development occurred in 23 patients (23.9%): 16 sagittal, 2 bilateral coronal, 4 unilateral coronal, and 1 lambdoid synostosis. Complete neosuture formation was seen in 14 of those 23 patients (9 of 16 sagittal, 1 of 2 bilateral coronal, 3 of 4 unilateral coronal, and 1 of 1 lambdoid). Mean pre- and postoperative CI in the complete sagittal neosuture group was 67.4% and 75.5%, respectively, and in the non-neosuture group was 69.8% and 74.4%, respectively. There was no statistically significant difference in the CI between the neosuture and fused suture groups preoperatively or 17 months postoperatively in patients with sagittal synostosis. CONCLUSIONS Neosuture development can occur after endoscope-assisted strip craniectomy and molding helmet therapy for patients with craniosynostosis. Although the authors did not detect a significant difference in calvarial shape postoperatively in the group with sagittal synostosis, the relevance of neosuture formation remains to be determined. Further studies are required to discover long-term outcomes comparing patients with and without neosuture formation.

A single-center experience with symptomatic postoperative calvarial growth restriction after extended strip craniectomy for sagittal craniosynostosis

2010 ◽  
Vol 5 (1) ◽  
pp. 131-135 ◽  
Author(s):  
Matthew A. Adamo ◽  
Ian F. Pollack
Keyword(s):  
Intracranial Pressure ◽  
Growth Restriction ◽  
Increased Intracranial Pressure ◽  
Sagittal Synostosis ◽  
Sagittal Craniosynostosis ◽  
Single Center Experience ◽  
Number Of Patients ◽  
Single Suture ◽  
Strip Craniectomy

Object Sagittal synostosis accounts for the most common form of craniosynostosis, occurring with an incidence of 1 in 2000–5000 live births. In most cases of single-suture, nonsyndromic sagittal synostosis, a single operation is all that is required to achieve a reasonable cosmetic result. However, there are a number of patients who may experience symptomatic postoperative calvarial growth restriction secondary to fibrosis of newly formed bone and pericranium that replace the surgically removed sagittal suture, or due to fusion of other previously open sutures leading to increased intracranial pressure, necessitating a second operation. Methods A retrospective review was conducted of all cases involving infants who had undergone an extended sagittal strip craniectomy with bilateral parietal wedge osteotomies at our institution between 1990 and 2006 for single-suture, nonsyndromic sagittal craniosynostosis. The frequency with which subsequent operations were required for cranial growth restriction was then defined. Results There were a total of 164 patients with single-suture nonsyndromic sagittal synostosis. Follow-up data were available for 143 of these patients. The average age at time of initial operation was 5.25 months, and the mean duration of follow-up was 43.85 months. There were 2 patients (1.5%) who required a second operation for symptomatic postoperative calvarial growth restriction. Conclusions Recurrence of synostosis with resultant increased intracranial pressure in cases of single-suture, nonsyndromic sagittal craniosynostosis is an uncommon event, but does occur sporadically and unpredictably. Therefore, we recommend routine neurosurgical follow up for at least 5 years, with regular ophthalmological examinations to assess for papilledema.

A comparison of endoscopic strip craniectomy and pi craniectomy for treatment of sagittal craniosynostosis

2019 ◽  
Vol 23 (6) ◽  
pp. 708-714
Author(s):  
Suresh N. Magge ◽  
Arthur R. Bartolozzi ◽  
Neil D. Almeida ◽  
Deki Tsering ◽  
John S. Myseros ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Hospital Length ◽  
Hospital Length Of Stay ◽  
Sagittal Craniosynostosis ◽  
Cranial Index ◽  
Helmet Therapy ◽  
Operative Strategies ◽  
Single Suture ◽  
Strip Craniectomy

OBJECTIVESagittal craniosynostosis is managed with a wide variety of operative strategies. The current investigation compares the clinical outcomes of two widely performed techniques: pi craniectomy and minimally invasive endoscopic strip craniectomy (ESC) followed by helmet therapy.METHODSThis IRB-approved retrospective study examined patients diagnosed with nonsyndromic, single-suture sagittal craniosynostosis treated with either pi craniectomy or ESC. Included patients had a minimum postoperative follow-up of 5 months.RESULTSFifty-one patients met the inclusion criteria (pi 21 patients, ESC 30 patients). Compared to patients who underwent ESC, the pi patients were older at the time of surgery (mean age 5.06 vs 3.11 months). The mean follow-up time was 23.2 months for ESC patients and 31.4 months for pi patients. Initial cranial index (CI) was similar between the groups, but postoperatively the ESC patients experienced a 12.3% mean increase in CI (from 0.685 to 0.767) compared to a 5.34% increase for the pi patients (from 0.684 to 0.719), and this difference was statistically significant (p < 0.001). Median hospital length of stay (1 vs 2 days) and operative duration (69.5 vs 93.3 minutes) were significantly less for ESC (p < 0.001 for both). The ESC patients showed a trend toward better results when surgery was done at younger ages. Craniectomy width in ESC cases was positively associated with CI improvement (slope of linear regression = 0.69, p = 0.026).CONCLUSIONSWhile both techniques effectively treated sagittal craniosynostosis, ESC showed superior results compared to pi craniectomy. ESC showed a trend for better outcomes when done at younger ages, although the trend did not reach statistical significance. A wider craniectomy width (up to 2 cm) was associated with better outcomes than smaller craniectomy widths among the ESC patients.

Endoscopic treatment of combined metopic-sagittal craniosynostosis

2020 ◽  
Vol 26 (2) ◽  
pp. 113-121
Author(s):  
Ema Zubovic ◽  
Gary B. Skolnick ◽  
Sybill D. Naidoo ◽  
Mark Bellanger ◽  
Matthew D. Smyth ◽  
...  
Keyword(s):  
Endoscopic Treatment ◽  
Ct Scans ◽  
Sagittal Synostosis ◽  
Sagittal Craniosynostosis ◽  
Cranial Index ◽  
Helmet Therapy ◽  
The Mean ◽  
Normal Controls ◽  
Cranial Vault Remodeling

OBJECTIVECombined metopic-sagittal craniosynostosis is traditionally treated with open cranial vault remodeling and fronto-orbital advancement, sometimes in multiple operations. Endoscopic treatment of this multisuture synostosis presents a complex challenge for the surgeon and orthotist.METHODSThe authors retrospectively analyzed the preoperative and 1-year postoperative CT scans of 3 patients with combined metopic-sagittal synostosis, all of whom were treated with simultaneous endoscope-assisted craniectomy of the metopic and sagittal sutures followed by helmet therapy. Established anthropometric measurements were applied to assess pre- and postoperative morphology, including cranial index and interfrontal divergence angle (IFDA). Patients’ measurements were compared to those obtained in 18 normal controls.RESULTSTwo boys and one girl underwent endoscope-assisted craniectomy at a mean age of 81 days. The mean preoperative cranial index was 0.70 (vs control mean of 0.82, p = 0.009), corrected postoperatively to a mean of 0.82 (vs control mean of 0.80, p = 0.606). The mean preoperative IFDA was 110.4° (vs control mean of 152.6°, p = 0.017), corrected postoperatively to a mean of 139.1° (vs control mean of 140.3°, p = 0.348). The mean blood loss was 100 mL and the mean length of stay was 1.7 days. No patient underwent reoperation. The mean clinical follow-up was 3.4 years.CONCLUSIONSEndoscope-assisted craniectomy with helmet therapy is a viable single-stage treatment option for combined metopic-sagittal synostosis, providing correction of the stigmata of trigonoscaphocephaly, with normalization of the cranial index and IFDA.

scholarly journals Endoscope-assisted strip craniectomy and postoperative helmet therapy for treatment of craniosynostosis

2011 ◽  
Vol 31 (2) ◽  
pp. E5 ◽  
Author(s):  
John Berry-Candelario ◽  
Emily B. Ridgway ◽  
Ronald T. Grondin ◽  
Gary F. Rogers ◽  
Mark R. Proctor
Keyword(s):  
Hospital Stay ◽  
Operative Time ◽  
Average Length ◽  
A Priori ◽  
Length Of Hospital Stay ◽  
Blood Transfusions ◽  
Helmet Therapy ◽  
Age At Surgery ◽  
Strip Craniectomy

Object The primary goals of treatment in the infant with craniosynostosis are to correct the deformity and allow for adequate brain growth in as safe and effective a manner as possible. Herein, the authors present the results of treating craniosynostosis using an endoscope-assisted strip craniectomy and postoperative helmet therapy (EASC + PHT) in the hopes of providing further evidence of its role in the treatment of multiple different forms of craniosynostosis. This is a retrospective review of the patients treated with this technique at Children's Hospital Boston. Methods The electronic medical records of all children with craniosynostosis treated using this technique were reviewed retrospectively. A priori, data were collected for deformity type, patient age at surgery, number of transfusions, operative time, length of hospital stay, and anthropometric measurements. Results One hundred seventy-three patients (61 females and 112 males) were treated at our institution between July 2004 and March 2011 with EASC + PHT. The mean operative time was 46.30 minutes. Eight (4.6%) of the 173 patients received blood transfusions. The average length of hospital stay was 1.35 days, with the majority of patients being discharged the day after surgery. All complications and any patient who required additional craniofacial reconstructions are discussed. In addition, a subgroup analysis was done for patients who had undergone surgery and had longer than 1 year of follow-up. Conclusions The authors' growing database of patients supports the experiences described by others that early treatment of craniosynostosis with an EASC + PHT is a safe and efficacious technique. In addition, cost reduction due to decreased hospital stay and limitation of blood transfusions are demonstrable benefits associated with the use of this technique.

Comparison of Perioperative Outcomes and Parental Satisfaction Outcomes of Strip Craniectomy with Postoperative Helmet versus Spring-Mediated Remodeling in Sagittal Craniosynostosis

2021 ◽  
pp. 1-8
Author(s):  
Luke G.F. Smith ◽  
Varun Shah ◽  
Helen Duenas ◽  
Amanda Onwuka ◽  
Anne E. Graver ◽  
...  
Keyword(s):  
Parental Satisfaction ◽  
Outcome Data ◽  
Perioperative Outcomes ◽  
Long Term Outcomes ◽  
Sagittal Craniosynostosis ◽  
Estimated Blood Loss ◽  
Age At Surgery ◽  
Strip Craniectomy

<b><i>Introduction:</i></b> We sought to compare outcomes and parental satisfaction between 2 approaches for sagittal craniosynostosis: strip craniectomy with spring-mediated skull remodeling (SMSR) and strip craniectomy with postoperative helmet (SCH). <b><i>Methods:</i></b> Perioperative and outcome data for SMSR or SCH patients between September 2010 and July 2019 were retrospectively reviewed. A telephone survey was administered to parents of children who underwent both procedures. <b><i>Results:</i></b> A total of 62 children were treated for sagittal craniosynostosis by either SMSR (<i>n</i> = 45) or SCH (<i>n</i> = 17). The SCH group had a lower estimated blood loss (27 vs. 47.06 mL, <i>p</i> = 0.021) and age at surgery (13.0 vs. 19.8 weeks) than the SMSR group. Three patients underwent early springs removal due to trauma or dislodgement, all of whom converted to helmeting. Of the 62 children initially identified, 59 were determined to have an adequate follow-up time to assess long-term outcomes. The mean follow-up time was 30.1 months (<i>n</i> = 16) in the SCH group and 32.0 months in the SMSR group (<i>n</i> = 43, <i>p</i> = 0.39). Two patients in the SCH group and one in the SMSR group converted to open cranial vault reconstruction. Thirty parents agreed to respond to the satisfaction survey (8 SCH, 22 SMSR) based on a Likert scale of responses (0 being most dissatisfied possible, 4 most satisfied possible). Average satisfaction was 3.86/4.0 in the SCH group and 3.45/4.0 in the SMSR group. No parents in the SCH group would change to SMSR, while 3 of the 22 SMSR survey responders would have changed to SCH. <b><i>Conclusions:</i></b> Perioperative outcomes and average parental satisfaction were similar in both groups. Importance of helmet wear compliance and risk of spring dislodgement should be discussed with parents.

scholarly journals Less is more: does the addition of barrel staves improve results in endoscopic strip craniectomy for sagittal craniosynostosis?

2017 ◽  
Vol 20 (1) ◽  
pp. 86-90 ◽  
Author(s):  
Benjamin C. Wood ◽  
Edward S. Ahn ◽  
Joanna Y. Wang ◽  
Albert K. Oh ◽  
Robert F. Keating ◽  
...  
Keyword(s):  
Consecutive Series ◽  
Less Is More ◽  
Sagittal Craniosynostosis ◽  
Group A ◽  
The Mean ◽  
The Difference ◽  
Scan Data ◽  
Group B ◽  
Strip Craniectomy

OBJECTIVEEndoscopic strip craniectomy (ESC) with postoperative helmet orthosis is a well-established treatment option for sagittal craniosynostosis. There are many technical variations to the surgery ranging from simple strip craniectomy to methods that employ multiple cranial osteotomies. The purpose of this study was to determine whether the addition of lateral barrel-stave osteotomies during ESC improved morphological outcomes.METHODSAn IRB-approved retrospective review was conducted on a consecutive series of cases involving ESC for sagittal craniosynostosis at 2 different institutions from March 2008 to August 2014. The patients in Group A underwent ESC and those in Group B had ESC with lateral barrel-stave osteotomies. Demographic and perioperative data were recorded; postoperative morphological outcomes were analyzed using 3D laser scan data acquired from a single orthotic manufacturer who managed patients from both institutions.RESULTSA total of 73 patients were included (34 in Group A and 39 in Group B). Compared with Group B patients, Group A patients had a shorter mean anesthetic time (161.7 vs 195 minutes; p < 0.01) and operative time (71.6 vs 111 minutes; p < 0.01). The mean hospital stay was similar for the 2 groups (1.2 days for Group A vs 1.4 days for Group B; p = 0.1). Adequate postoperative data on morphological outcomes were reported by the orthotic manufacturer for 65 patients (29 in Group A and 36 in Group B). The 2 groups had similar improvement in the cephalic index (CI): Group A, mean change 10.5% (mean preoperative CI 72.6, final 80.4) at a mean follow-up of 13.2 months; Group B, mean change 12.2% (mean preoperative CI 71.0, final 79.6) at a mean follow-up of 19.4 months. The difference was not statistically significant (p = 0.15).CONCLUSIONSBoth ESC alone and ESC with barrel staving produced excellent outcomes. However, the addition of barrel staves did not improve the results and, therefore, may not be warranted in the endoscopic treatment of sagittal craniosynostosis.

scholarly journals Assessment of spring cranioplasty biomechanics in sagittal craniosynostosis patients

2017 ◽  
Vol 20 (5) ◽  
pp. 400-409 ◽  
Author(s):  
Alessandro Borghi ◽  
Silvia Schievano ◽  
Naiara Rodriguez Florez ◽  
Roisin McNicholas ◽  
Will Rodgers ◽  
...  
Keyword(s):  
Spring Model ◽  
Patient Age ◽  
Street Hospital ◽  
Great Ormond Street Hospital ◽  
Sagittal Craniosynostosis ◽  
Patient Âgé ◽  
Age At Surgery ◽  
Initial Force ◽  
Implantation Period

OBJECTIVEScaphocephaly secondary to sagittal craniosynostosis has been treated in recent years with spring-assisted cranioplasty, an innovative approach that leverages the use of metallic spring distractors to reshape the patient skull. In this study, a population of patients who had undergone spring cranioplasty for the correction of scaphocephaly at the Great Ormond Street Hospital for Children was retrospectively analyzed to systematically assess spring biomechanical performance and kinematics in relation to spring model, patient age, and outcomes over time.METHODSData from 60 patients (49 males, mean age at surgery 5.2 ± 0.9 months) who had received 2 springs for the treatment of isolated sagittal craniosynostosis were analyzed. The opening distance of the springs at the time of insertion and removal was retrieved from the surgical notes and, during the implantation period, from planar radiographs obtained at 1 day postoperatively and at the 3-week follow-up. The force exerted by the spring to the patient skull at each time point was derived after mechanical testing of each spring model—3 devices with the same geometry but different wire thicknesses. Changes in the cephalic index between preoperatively and the 3-week follow-up were recorded.RESULTSStiffer springs were implanted in older patients (p < 0.05) to achieve the same opening on-table as in younger patients, but this entailed significantly different—higher—forces exerted on the skull when combinations of stiffer springs were used (p < 0.001). After initial force differences between spring models, however, the devices all plateaued. Indeed, regardless of patient age or spring model, after 10 days from insertion, all the devices were open.CONCLUSIONSResults in this study provide biomechanical insights into spring-assisted cranioplasty and could help to improve spring design and follow-up strategy in the future.

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