Fredrik Gewalli
Sahlgrenska University Hospital
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Featured researches published by Fredrik Gewalli.
Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 2003
José Guimarães-Ferreira; Fredrik Gewalli; Lisa David; Robert Olsson; Hans Friede; Claes Lauritzen
The aim of this study was to compare the safety, morphological outcome, and degree of parental satisfaction of the new spring-mediated cranioplasty with those of the modified pi-plasty in the management of sagittal synostosis. Ten patients with non-syndromic sagittal synostosis treated with the spring-mediated cranioplasty were followed prospectively. A control group of 10 sex-matched patients operated on with the modified pi-plasty procedure was chosen. Cephalometric radiographs were obtained preoperatively and postoperatively at 1 year of age. Cephalic index, axial width ratio, length ratio, width ratio and height ratio were used as objective measures of outcome. Parents were sent a questionnaire to obtain a subjective aesthetic assessment of outcome. Significantly less blood replacement was required (p = 0.003), and shorter duration of postoperative anaesthesia (p = 0.030) and postoperative hospital stay (p = 0.013) were found in the spring-mediated cranioplasty group. There were no complications or deaths in either group. Also significant was the inter-group difference in the postoperative change in the height ratio (p = 0.030), the most change being seen in the spring group. The change in the subjective parental aesthetic evaluation of skull shape was significant in both groups. In conclusion, the spring-mediated procedure was morphologically more effective than the modified pi-plasty procedure in the management of sagittal synostosis with the additional benefits of less blood transfusion needed and shorter duration of hospital stay.
Journal of Craniofacial Surgery | 2001
José Guimarães-Ferreira; Fredrik Gewalli; Lisa R. David; Robert Olsson; Hans Friede; Claes Lauritzen; Michael T. Longaker; David C. Hemmy
The aim of the study was to evaluate the modified pi-plasty procedure for the treatment of sagittal synostosis, assessing the issues of safety, complications, morphological outcome, and degree of parental satisfaction. A retrospective evaluation of 110 patients with nonsyndromal single suture sagittal synostosis operated on with the modified pi-plasty procedure was undertaken. Cephalometric radiographs were obtained preoperatively and postoperatively at ages 3 and 5 years in three standardized projections. The Cephalic Index and the Axial Width Ratio were determined and used as objective outcome measures. An evaluation of the radiographic digital markings was carried out using a Beaten Copper Score. A parental questionnaire was used to obtain a subjective esthetical outcome assessment. The patient population consisted of 76% boys and 24% girls with a 20% incidence of a positive familial history of craniosynostosis. The mean age at surgery was 7.73 months. Morbidity from the procedure was minimal and there were no mortalities. The Cephalic Index changed from a mean preoperative value of 65% to a postoperative mean value of 72% (P = 0.00004). The mean Axial Width Ratio changed from a preoperative 80% to 72% at the 3-year evaluation (P = 0.00029). The Beaten Copper score changed from a mean preoperative value of 2.35 to 5.42 postoperatively at 3 years (P = 0.00001). The response rate to the questionnaire was 86%, and there were significant postoperative improvements in all studied aspects of the skull shape. The modified pi-plasty is a safe technique, and it induces significant objective changes in skull morphology toward normality. It also yields a high degree of parental satisfaction with regard to aesthetic outcome, as evaluated by a written questionnaire.
Annals of Plastic Surgery | 2001
Fredrik Gewalli; José Guimarães-Ferreira; Pelle Sahlin; Ingrid Emanuelsson; Göran Horneman; Hannes Stephensen; Claes Lauritzen
A prospective developmental assessment was performed on 26 patients operated on with dynamic cranioplasty for sagittal synostosis. Because this technique entails the application of compressive force, it was of great concern to assess the effect of surgery on development and mental status. The surgical technique used was a modified &pgr; procedure. Perioperative variables were recorded. Six patients underwent preoperative intracranial pressure (ICP) measurements. To evaluate objectively the developmental outcome, the Griffiths’ Mental Development Scales was used for analysis before and after surgery. A parental questionnaire was used for subjective outcome measurement. Preoperative ICP recordings during sleep ranged from 12.8 to 22.8 mmHg (mean, 16.1 mmHg). The mean age at the time for surgery was 6.9 months (range, 4–16 months; standard deviation [SD], 2.32 months). The surgical technique included shortening of the anteroposterior diameter of the skull by a mean of 16.6 mm. The mean global development quotient (GDQ) preoperatively was 104.5 (range, 82–144; SD, 12.4) and the mean GDQ postoperatively was 101.4 (range, 62–129; SD, 13.6). Mean age at follow-up was 16.3 months (range, 9–40 months; SD, 4.04 months). There was no significant correlation between the amount of intraoperative shortening and mental development. In comparison of means, the GDQ preoperatively did not differ significantly from the GDQ postoperatively. The modified &pgr; procedure is safe and efficient. When surgery was performed before 1 year of age, no significant (p = 0.33) effect on mental development-either detrimental or beneficial-was demonstrated.
Journal of Craniofacial Surgery | 2002
Lisa R. David; Fredrik Gewalli; José Guimarães-Ferreira; Claire Sanger; Steve Glazier; Louis C. Argenta
Since the beginning of craniofacial surgery, there has been an ongoing search for surgical techniques to enhance outcome while, at the same time, decreasing the invasiveness of the surgical treatment of craniofacial deformities. The purpose of this study was to test a recently reported minimally invasive treatment modality, the dynamic spring, in a rabbit calvarial model for efficacy and safety. Specifically, the results of spring cranioplasty on skull growth, the underlying brain, and adjacent bone were to be assessed. The study population consisted of 36 7-week-old New Zealand white rabbits. The rabbits were divided into four treatment groups (9 rabbits each): control, sham surgery, stainless steel springs, and memory metal springs. Postoperative analysis included weekly radiographs to evaluate movement of amalgam markers placed at standardized locations. Additionally, 16 rabbits (4 from each group) were killed at 14 days after surgery, and postmortem histological analysis was done. The remaining rabbits were followed until they were adults and were then killed and similarly analyzed. No morbidity or mortality occurred in the immediate perioperative period secondary to the surgery. Postmortem histological analysis of all study animals revealed no intracranial, subcutaneous, or skin infections and no technical complications related to the surgery. Statistical analysis using ANOVA and pair-wise comparisons between treatment groups revealed a statistically significant difference (P < 0.05) between the marker movement in the spring groups versus the sham and control groups. There were no significant differences between the sham and control groups or between the two spring groups. In conclusion, this study confirms the efficacy and safety of the dynamic spring in a rabbit model.
Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 2001
Fredrik Gewalli; José Guimarães-Ferreira; Giovanni Maltese; Ulf Örtengren; Claes Lauritzen
With the inception of craniofacial surgery elaborate surgical procedures were introduced for the treatment of craniosynostosis. Recently the use of implantable springs to aid simple strip craniectomies forthese conditions has been described. Havingshown the feasibility of using springs for dynamic skull reshaping, several questions remain to be answered, all of them about how to control the spring action clinically. One of the most important questions concerns force. The purpose of this study was to evaluate experimentally the effect of two springs of different strengths on the growth of rabbit calvaria after strip craniectomy. Thirty-two 6-week-old rabbits were randomised into one of four groups: sham-operation where only amalgam markers were inserted after subperiostal dissection; strip craniectomy of the sagittal suture, no expansion; strip craniectomy of the sagittal suture and insertion of an expander element made of titanium molybdenum alloy(TMA); and strip craniectomy sagittal suture and insertion of an expander element made of stainless steel (SS). SS springs delivered a range of forces from 2.42-2.18 N, whereas the TMA expander elements delivered a range from 1.39-1.09N.The parietal bonemarker separation after 12 weeks was 4.9 mm in the TMA group and 7.4 mm in the SS group. This resulted in a significant increase of the calvarian height compared with control groups. Histological examination showed intramembranous bone formation in the bone gap in all groups.With the inception of craniofacial surgery elaborate surgical procedures were introduced for the treatment of craniosynostosis. Recently the use of implantable springs to aid simple strip craniectomies for these conditions has been described. Having shown the feasibility of using springs for dynamic skull reshaping, several questions remain to be answered, all of them about how to control the spring action clinically. One of the most important questions concerns force. The purpose of this study was to evaluate experimentally the effect of two springs of different strengths on the growth of rabbit calvaria after strip craniectomy. Thirty-two 6-week-old rabbits were randomised into one of four groups: sham-operation where only amalgam markers were inserted after subperiostal dissection; strip craniectomy of the sagittal suture, no expansion; strip craniectomy of the sagittal suture and insertion of an expander element made of titanium molybdenum alloy (TMA); and strip craniectomy sagittal suture and insertion of an expander element made of stainless steel (SS). SS springs delivered a range of forces from 2.42-2.18 N, whereas the TMA expander elements delivered a range from 1.39-1.09 N. The parietal bone marker separation after 12 weeks was 4.9 mm in the TMA group and 7.4 mm in the SS group. This resulted in a significant increase of the calvarian height compared with control groups. Histological examination showed intramembranous bone formation in the bone gap in all groups.
Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 2001
Clas Lossing; Anna Elander; Fredrik Gewalli; Hans Holmström
Fifty-four patients were studied a mean of five years after their breasts had been reconstructed between 1984 and 1990 using the lateral thoracodorsal (LTD) flap in combination with either a thin shell, non-low-bleed (n = 35) or a thick shell, low bleed (n = 19) silicone gel implant. The rate of capsular contracture (Baker III-IV) was 11% in the first group and 10% in the second according to a modified Baker classification. Open capsulotomy was common in both groups of patients (15/35 in the first group and 13/19 in the second). Investigation by applanation tonometry of the capsular contracture agreed with the modified Baker classification. The cosmetic results were evaluated clinically and from photographs. Best scores were recorded for scars and ptosis in both evaluations. There were no significant differences between the general cosmetic results in the two groups. The patients graded their estimations of the final outcome of their breast reconstruction on a 10-point visual analogue scale (VAS); the mean for the first group was 8.7 and for the second 9.2. None of the patients regretted her operation and they would all recommend the procedure to another patient.Fifty-four patients were studied a mean of five years after their breasts had been reconstructed between 1984 and 1990 using the lateral thoracodorsal (LTD) flap in combination with either a thin shell, non-low-bleed (n = 35) or a thick shell, low bleed (n = 19) silicone gel implant. The rate of capsular contracture (Baker III-IV) was 11% in the first group and 10% in the second according to a modified Baker classification. Open capsulotomy was common in both groups of patients (15/35 in the first group and 13/19 in the second). Investigation by applanation tonometry of the capsular contracture agreed with the modified Baker classification. The cosmetic results were evaluated clinically and from photographs. Best scores were recorded for scars and ptosis in both evaluations. There were no significant differences between the general cosmetic results in the two groups. The patients graded their estimations of the final outcome of their breast reconstruction on a 10-point visual analogue scale (VAS); the mean for the first group was 8.7 and for the second 9.2. None of the patients regretted her operation and they would all recommend the procedure to another patient.
Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 2006
José Guimarães-Ferreira; Fredrik Gewalli; Lisa David; Tron A. Darvann; Nuno V. Hermann; Sven Kreiborg; Hans Friede; Claes Lauritzen
The aim of this study was to characterise the preoperative morphology of the skull in sagittal synostosis in an objective and quantified way. The shapes of the skulls of 105 patients with isolated premature synostosis of the sagittal suture (SS group) were studied and compared with those of a control group of 72 children with unilateral incomplete cleft lip (UICL). A standardised radiocephalometric technique was used to obtain the images. A modification of a method developed by Kreiborg was used to analyse the radiocephalograms, which included the digitisation of 88 landmarks in the calvaria, skull base, and orbit (42 in the lateral and 46 in the frontal projections), the production of plots of mean shape for each group, and the intergroup comparison of a series of 81 variables (linear distance between selected landmarks, and angles defined by groups of three landmarks). Data from a subgroup of 66 patients aged 5 to 8 months were further compared to age-matched normative data in terms of seven angular and linear calvarial, cranial base and orbital variables. In a comparative analysis of the mean lateral plots, the foreheads of the study group (SS) had a more pronounced anterior slope and were also more convex. The vertex area was located more anteriorly, and was less convex. The occipital curvature was more prominent. Analysis of the mean frontal plots revealed a lack in convexity and lateral projection of the upper parietal regions, as well as a lower location of the line of maximum skull width. Comparison of the mean values of an SS subgroup to age-matched normative data showed a longer (p<0.001) and narrower skull (p<0.001) and a greater interorbital distance (p<0.001). The cranial base angle, the sella to nasion, and sella to basion lengths did not differ significantly. Sagittal synostosis is characterised by an extensive deformity of the cranial vault, with an essentially normal cranial base. The widened interorbital distance is probably related to compensatory metopic hyperactivity.
Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 2003
Fredrik Gewalli; Pelle Sahlin; José Guimarães-Ferreira; Claes Lauritzen
In the 10-year period 1986-1996, 85 patients were admitted to our unit with craniofacial injuries, 56 of whom had orbital fractures. These were studied with respect to the type of injury, type and location of fracture, presence of ocular and intracranial injury, and associated injuries to the head and body, as well as operative techniques used. Both the patients and the surgeons opinion on the aesthetic result were noted. The patients were also given a questionnaire about their quality of life after the injury. Road traffic crashes accounted for 31 (55%) of the injuries, falls for 9 (15%), and horse-riding for 6 (11%). The Injury Severity Score (ISS) ranged from 4 to 41 (mean 18). Twelve also had eye injuries, which resulted in complete blindness in one eye in 4 (7%). Thirty patients had 41 neurological injuries (54%), frontal contusions being the most frequent diagnosis ( n r = r 15). Exact repositioning with rigid fixation included bone grafting to the orbit in 11 patients, and the dominating bone graft was split calvarium ( n r = r 5). Forty-two patients completed a questionnaire, 26 of whom (64%) had no aesthetic complaints. Seven of the 42 were too disabled to work one year after the injury. Re-exploration was infrequent and the aesthetic outcome, both in the surgeons and the patients opinion, was good. However, the older the patient, the worse the outcome.
Plastic and Reconstructive Surgery | 2008
Hans Holmström; Fredrik Gewalli
Background: Growth inhibition of the ossification center, “the external trabecular network,” would result in localized hypoplasia of nasomaxillary structures, resulting in the typical features of the Binder syndrome patient, with the retracted columella/lip junction and a lack of the normal triangular flare in the lower part of the columella. This study focused on a long-term follow-up of more than 5 years for three different grafting techniques. Methods: Ninety-two patients with Binder syndrome were subjects for consecutive reconstructive plastic surgery between 1972 and 1995. The primary surgical approach was degloving the midface subperiosteally, and reconstruction was identical but differed in the grafts used: septum repositioning (n = 26), L-shaped bone graft (n = 51), or L-shaped cartilage graft (n = 15). Anthropometric variables on digitalized profile photographs were used. Results: The angle of convexity of the face at the tip of the nose (glabella-pronasale-pogonion) improved in all three groups from 155 to 158 degrees to 144 to 149 degrees at the short-term follow-up and to 148 to 149 degrees at the long-term follow-up. The nasolabial angle changed, from a narrow angle of 76 to 88 degrees in all groups before surgery, to 100 to 106 degrees at the long-term follow-up after surgery. Conclusions: The L-shaped bone graft was favorably used in the depressed nasal dorsum, whereas frontal repositioning of the septum was optimal when the upper part of the nose was considered normal. The consistency in tip projection for all groups over time may be explained by the extensive surgical release of the soft tissues before grafting.
Journal of Craniofacial Surgery | 2008
Fredrik Gewalli; Fidel Berlanga; Fernando Ortiz Monasterio; Hans Holmström
Maxillonasal dysplasia is characterized by a concave facial profile and a flat nose. The etiology of Binder syndrome is skeletal hypoplasia around the piriform aperture and excavations-fossae prenasales, bilaterally in the nasal floor-which are pathognomonic. There is no real shortage of the soft tissues. In 2 medical centers in Sweden and Mexico, different grafts were used for reconstruction, but the focus was similar, filling out the maxilla anterior to the nasal floor and supporting the nasal framework to normalize tip projection. The basis for this study was to compare the long-term results between bone grafts in Sweden and cartilage grafts in Mexico. Sixteen patients from both groups were available for long-term follow-up. Simplified digital analysis of anthropometric variables were performed in the short-term and long-term follow-ups. The Swedish group had primary at the mean age of 21.3 years, whereas mean follow-up period was 16.8 years later. The Mexican group had primary at the age of 13.6 years, and the follow-up period was 8.4 years. Secondary correction was necessary in 25% of the patients in the bone graft group (Sweden) and in 19% of patients in the cartilage group (Mexico). Bone grafts slightly relapsed in tip projection and remodeled to some extent in the nasolabial angle. Cartilage grafts showed stability in the tip projection quotients and resulted in a postoperative normalization of the nasolabial angle but developed a slight relapse between the short-term and long-term follow-ups. Both techniques were stable in nose tip-length ratio, and a normalization of anthropometric variables was demonstrated in all the long-term follow-ups. Both the bone and cartilage graft techniques at the 2 centers rendered the intended result of an increased and normalized angle of convexity of the face and nasal tip projection. An experience in the properties and behavior of either graft is necessary to get a long-term stable outcome.