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Dive into the research topics where Ola Larson is active.

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Featured researches published by Ola Larson.


The Cleft Palate-Craniofacial Journal | 1998

Incidence of cleft lip and palate and risks of additional malformations.

Catharina Hagberg; Ola Larson; Josef Milerad

OBJECTIVE AND METHODS Children with cleft lip and/or palate (n = 251) born between 1991 and 1995 in the county of Stockholm, Sweden, were studied with reference to incidence and rate ratios (RRs) of different types of clefts, gender, birth weight, mothers age, and length of pregnancy. Children who had clefts and additional malformations were compared with children who had clefts but no additional malformations. RESULTS The incidence of clefts was 2.0/1000 live births, and it was higher among males than among females. The RR, an index of relative risk, was 1.58. The main groups, children with isolated cleft lip, children with cleft lip and palate, and children with isolated cleft palate, showed similar incidence values (0.6-0.7/1000 live births). Children with bilateral clefts had an incidence of 0.3/1000 live births. Additional malformations were found in approximately every sixth newborn with a cleft when children with Robin sequence were excluded. There was a tendency for newborns with bilateral clefts to have additional malformations (RR = 1.36; confidence interval = 0.74-2.49). Children with clefts and additional malformations had lower birth weight and were born earlier than children with clefts only. CONCLUSION Preterm cleft children with low birth weight should be screened for the presence of other birth defects.


Oral Surgery, Oral Medicine, Oral Pathology | 1986

Hyperplastic soft-tissue formation in the temporomandibular joint associated with internal derangement: A radiographic and histologic study☆

Annika Isberg; Göran Isacsson; Ann-Sofi Johansson; Ola Larson

Hyperplastic connective tissue formation in the posterior part of the temporomandibular joint glenoid fossa has previously been described in autopsy specimens. The frequency of such hyperplastic tissue formation in patients with long-standing temporomandibular joint pain was studied in 103 joints from 80 patients by means of double-contrast arthrotomography. Five joints in four patients (5%) demonstrated hyperplastic tissue formation; in four cases this was associated with permanently displaced and deformed disks. All five joints were refractory to nonsurgical treatment. Surgically extirpated hyperplastic tissue and disk attachments contained nerve fibers and thickened adventitia of vessels, resulting in narrowed or obliterated lumina, extravasated erythrocytes, and fibrinlike deposits. The synovial membrane showed fibrinoid necrosis or was lost. The pain reaction in temporomandibular joints with hyperplastic soft-tissue formation may be released by compression or tension of nerves, breaking down products from blood or tissue ischemia. Contrast filling of both joint spaces, combined with tomography, was required for detection of the hyperplastic tissue formation.


European Journal of Human Genetics | 2001

Mapping of the second locus for the Van der Woude syndrome to chromosome 1p34

Hannele Koillinen; Fung Ki Wong; Jorma Rautio; Vesa Ollikainen; Agneta Karsten; Ola Larson; Bin Tean Teh; Jan Huggare; Päivi Lahermo; Catharina Larsson; Juha Kere

The Van der Woude syndrome (VWS) is a dominantly inherited developmental disorder characterized by pits and/or sinuses of the lower lip, cleft lip and/or cleft palate. It is the most common cleft syndrome. VWS has shown remarkable genetic homogeneity in all populations, and so far, all families reported have been linked to 1q32-q41. A large Finnish pedigree with VWS was recently found to be unlinked to 1q32-q41. In order to map the disease locus in this family, a genome wide linkage scan was performed. A maximum lod score of 3.18 was obtained with the marker D1S2797, thus assigning the disease locus to chromosomal region 1p34. By analyses of meiotic recombinants an ∼30 cM region of shared haplotypes was identified. The results confirm the heterogeneity of the VWS syndrome, and they place the second disease locus in 1p34. This finding has a special interest because the phenotype in VWS closely resembles the phenotype in non-syndromic forms of cleft lip and palate.


The Cleft Palate-Craniofacial Journal | 1993

Speech in Unilateral and Bilateral Cleft Palate Patients from Stockholm

Jonas Karling; Ola Larson; Rolf Leanderson; Gunilla Henningsson

The speech of 84 patients with complete unilateral cleft lip and palate and 19 patients with complete bilateral cleft lip and palate was judged by professional listeners and compared with a control group of 40 noncleft subjects. The unilateral cleft group consisted of two subgroups: one group of 45 patients, who were treated with presurgical orthopedics before primary surgery, and one group of 39 patients, who were not. The speech of the patients and the noncleft subjects was tape recorded and randomly mixed prior to listener judgments. No significant differences in articulation or resonance were found between the subgroups of unilateral cleft patients. The results also indicated that the bilateral cleft patients had poorer speech and needed more speech therapy than the unilateral cleft patients. All cleft patients were found to have poorer speech than the noncleft subjects in spite of considerable speech therapy and complementary surgical treatment. This has resulted in a change in the Stockholm approach toward earlier palatal surgery, tailor-made pharyngeal flap operations, and earlier parental information and treatment of articulatory deviations.


Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 1989

Treatment of keloids with surgical excision and postoperative X-ray radiation.

Kjell-Ove Sällström; Ola Larson; Per Hedén; GÖRan Eriksson; Jan Erik Glas; Ulrik Ringborg

124 patients with keloids were treated with surgical excision followed by postoperative X-ray radiation, begun within 24 hours after surgery. Only patients with a two-year keloid history were included in this study. The treatment results were evaluated 6 and 24 months after treatment. There was good correlation agreement between subjective and objective evaluations. Good or excellent results were observed in 92% of the patients. Side effects were moderate. Slight hyperpigmentation was found in 31% of the patients and telangiectasis in 15%. It was concluded that excision and early postoperative irradiation constitute effective keloid treatment.


Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 1991

Craniofacial development in children with unilateral clefts of the lip, alveolus, and palate treated according to four different regimes. I. Maxillary development.

Viveca Brattström; John McWilliam; Ola Larson; Gunvor Semb

Lateral skull radiographs of 85 patients with unilateral clefts of the lip, alveolus, and palate treated according to four different regimes were compared at three different ages regarding maxillary development. Regimes that included primary bone grafting to the alveolus at six months of age resulted in inhibited anterior maxillary growth and reduced maxillary inclination. Regimes that included secondary bone grafting after eruption of the incisors but before the eruption of the canines, resulted in better maxillary development, but were not as good as regimes that omitted bone grafting altogether.


The Cleft Palate-Craniofacial Journal | 1999

Comparison Between Two Types of Pharyngeal Flap with Regard to Configuration at Rest and Function and Speech Outcome

Jonas Karling; Gunilla Henningsson; Ola Larson; Annika Isberg

OBJECTIVE In management of hypernasality, wide pharyngeal flaps have been advocated when pharyngeal wall adduction is limited. Pharyngeal flaps merged into a transversely split velum (TS flaps) are reported to be wider than if the velum is split in the midline (MS flaps). The hypothesis to be tested was that TS flaps are wider than MS flaps and are more caudally based. DESIGN In this prospective study, MS flaps were videoradiographically and nasopharyngoscopically compared with TS flaps at both rest and function. Pharyngoplasty was randomly performed by one of three surgeons and the radiographic examinations were carried out by one radiologist. The speech was assessed pre- and postoperatively. SETTING The Stockholm Cleft Palate Team, Sweden, treated all patients. PATIENTS After strict selection of the patients to avoid any uncontrolled impact on velopharyngeal sphincter function, 22 patients with limited pharyngeal adduction received TS flaps and 20 patients with good adduction received MS flaps. RESULTS The data failed to show any difference in location of flap base and in flap width at rest. During function, TS flaps demonstrated statistically significant widening of the flap base. TS flaps, but not MS flaps, often had a bulge that appeared to assist velopharyngeal closure in some patients. Speech evaluation revealed that both flap types corrected velopharyngeal insufficiency equally well. CONCLUSIONS TS flaps were not wider than MS flaps, and functional plasticity of the TS flap appeared essential for elimination of velopharyngeal insufficiency. Contribution of postoperative adaptation of the pharyngeal wall adduction remains to be clarified.


Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 1993

Oronasal fistulas in cleft palate patients and their influence on speech

Jonas Karling; Ola Larson; Gunilla Henningsson

The size, site, and influence on speech of oronasal fistulas were studied in 12 patients with unilateral and 32 with bilateral cleft lip and palate. There were more and larger fistulas in the bilateral group. The series was divided into: those with fistulas that affected speech (group A, n = 18) and those with fistulas that did not affect their speech (group B, n = 26). Group A had significantly larger fistulas than group B, but there were no differences in the sites of the fistulas, either between the bilateral and unilateral groups or between groups A and B. Most fistulas were located in the region of the incisive foramen or in the hard palate. Judgements by listeners and analyses by the NORAM instrument were made of the speech of 12 of the patients in group A before and after temporary covering of the fistulas. Significant differences in hypernasality, according to both listeners judgments and instrumental analyses were found. This finding is further evidence that an oronasal fistula can influence and contribute to velopharyngeal dysfunction.


European Journal of Orthodontics | 2008

Familial non-syndromic cleft lip and palate—analysis of the IRF6 gene and clinical phenotypes

Marie Pegelow; Myriam Peyrard-Janvid; Marco Zucchelli; Ingegerd Fransson; Ola Larson; Juha Kere; Catharina Larsson; Agneta Karsten

The aim of this study was to characterize Swedish families with non-syndromic cleft lip and/or palate (NSCL/P) for mutations or other sequence variants in the interferon regulatory factor 6 (IRF6) gene, as well as to describe their cleft phenotypes and hypodontia. Seventeen Swedish families with at least two family members with NSCL/P were identified and clinically evaluated. Extracted DNA from blood samples was used for IRF6 mutation screening. Exonic fragments of the IRF6 gene were sequenced and chromatograms were inspected. Statistical analysis was undertaken with marker- and haplotype association tests. No disease-associated IRF6 mutation could be determined in the families analyzed. One new and seven known single nucleotide polymorphisms (SNPs) were detected. The A allele of SNP rs861019 in exon 2 and the G allele of SNP rs7552506 in intron 3 showed association with cleft lip and palate (CLP; odds ratios of 3.1 and 5.45, respectively). Hypodontia was observed more commonly in individuals affected with CL/P as compared with family members without a cleft (P < 0.01). The hypodontia most often affected the cleft area, possibly representing a secondary effect. The distribution of cleft phenotypes in 15 of the 17 families with NSCL/P differed from the mixed cleft types seen in Van der Woude syndrome (VWS), in that CLP did not occur together with an isolated cleft palate within the same family. It was concluded that mutations of the IRF6 gene are not a common cause for cleft predisposition in Swedish NSCL/P families.


The Cleft Palate-Craniofacial Journal | 2009

Speech Results After One-Stage Palatoplasty With or Without Muscle Reconstruction for Isolated Cleft Palate

Jill Nyberg; Liisi Raud Westberg; Erik Neovius; Ola Larson; Gunilla Henningsson

Objective To investigate speech outcome between children with isolated cleft palate undergoing palatoplasty with and without muscle reconstruction and to compare speech outcomes between cleft and noncleft children. The number of subsequent velopharyngeal flaps was compared with respect to surgical techniques and cleft extent. Design Cross-sectional retrospective study. Participants One hundred four children aged 4 years, 0 months to 6 years, 0 months, 33 with isolated cleft of the soft palate, 53 with isolated cleft of the hard and soft palate, and 18 noncleft children. Interventions Two primary palate repair techniques: minimal incision technique (MIT) and minimal incision technique including muscle reconstruction (MITmr). Main Outcome Measures Perceptual judgment of seven speech parameters assessed on a five-point scale. Results No significant differences in speech outcomes were found between MIT and MITmr surgery groups. The number of velopharyngeal flaps was significantly lower after MITmr surgery compared to MIT surgery. The number of flaps was also significantly lower in children with cleft of the soft palate compared to children with cleft of the hard and soft palate. Children with cleft of the soft palate had significantly less glottal articulation and weak pressure consonants compared to children with cleft of the hard and soft palate. Conclusions The MITmr surgery technique was not significantly superior to the MIT technique regarding speech outcomes related to velopharyngeal competence, but had fewer velopharyngeal flaps, which is contradictory. Until a larger sample can be studied, we will continue to use MITmr for primary palate repair.

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Gunvor Semb

University of Manchester

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Catharina Larsson

Karolinska University Hospital

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Jonas Karling

Royal Institute of Technology

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Jorma Rautio

Helsinki University Central Hospital

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