Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “laterality defects”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1977

Lateral defects in velopharyngeal insufficiency. Diagnosis and treatment.

A variety of surgical techniques is available for the closure of substantial velopharyngeal defects. While the use of the centrally based pharyngeal flap remains the cornerstone of surgical treatment, there are patients who have poor lateral pharyngeal wall (LPW) mobility. After surgery that uses a centrally based flap, the speech result in such patients is less than optimal, since the poorly mobile LPW does not approximate to the central flap, thus creating a lateral defect. We have added the Towne view to our protocol for cine-speech studies to study better the lateral defects. This view is perpendicular to the velopharyngeal spincter and shows the true-purse-string nature of it. The incidence of such defects in our last 40 consecutive patients is reviewed. Based on the existence of a lateral defect, recommendations are made for a system of operations in the treatment of velopharyngeal insufficiency.

Adolescent↗
PubMed1988

Laterality defects in conjoined twins: implications for normal asymmetry in human embryogenesis.

We evaluated six pairs of conjoined twins: four pairs were dicephalus, and two were of the ischiopagus type. In three of the four dicephalus pairs, the right twin had an abnormality of laterality that included a right aortic arch, reversed great vessel orientation, bilateral right-sided isomerism of the lungs, asplenia, and situs inversus of the viscera. The left twin had normal great vessel orientation and situs solitus in each case. The finding that was unique in these three dicephalus twin pairs was their fused hearts, which were similar in orientation and configuration. The fourth dicephalus twin pair had one normally rotated heart, which was located in the midline and had normally placed chambers and great vessels. Each twin of this pair had normal visceral situs. In the two pairs of ischiopagus twins, each pair had two separate hearts, with normal cardiac structure and great vessel relationships. The viscera expressed normal laterality. Documentation of a defect in laterality in the right twin in three conjoined twin pairs with fusion of the hearts, combined with the presence of normal laterality in three pairs without cardiac fusion, has implications regarding the mechanisms leading to laterality of the human embryo. We suggest that rotation of the heart initiates the embryo's process of lateralization and that the laterality defects of the viscera seen in the right twin are a result of their abnormal cardiac rotation.

Abnormalities, Multiple↗
PubMed1990

Schizophrenic performance on line bisection: no simple lateralization defects.

Many studies have assessed the possible lateralization deficits of schizophrenics, and the results usually suggest left hemisphere dysfunction. Nevertheless, they have been variable. This may have been due to cognitive demand of the different tasks, not to changes in brain lateralization itself. In order to circumvent this problem, the present study evaluates the performance of schizophrenics on a simple but lateralized task, line bisection. Subjects bisected a line using either visual or tactile information, with the left or right hand, when it was placed in their left or right hemispace or directly in front of them. Schizophrenic subjects were not more erroneous than normals (variable error), nor were they biased differently from normals in either direction with either modality of sensory input (constant error). There were only two significant effects of group on the tactile line bisection, one of position x length x group and one of position x hand x end x length x group, both on constant error (directional bias). The lack of main effects and presence of interactions on these basic tasks suggests that apparent lateralization differences found in schizophrenic subjects are due not to a simple defect of brain lateralization but may stem from task demands and attention allocation.

Attention↗
PubMed1987

Defective lateralized attention for non-verbal sounds in developmental dyslexia.

The performance of dyslexic and control children--matched for age, sex, handedness and performance IQ--was compared on a dichotic listening task in which the stimuli were environmental sounds. Two findings emerged. First, the dyslexic group showed a normal, left ear perceptual advantage for these non-verbal materials. Second, the dyslexics were incapable of occluding dichotically presented sounds to the left ear when required to deploy attention only to sounds entering the right ear. This failure of unilateral selective attention was not found in the controls, nor in either group under a condition of left ear only attention. The data were interpreted as undermining the bihemispheric non-verbal processing hypothesis of developmental dyslexia. It was argued that the dyslexics' apparent inability to override voluntarily the reflexive lateral orienting mechanism was most consistent with explanatory models emphasizing defective functioning, or even malformation, of the left cerebral hemisphere alone.

Adolescent↗
PubMed1976

Reproducing the vertical-lateral defect space in obturator construction.

A method of incorporating vertical and horizontal tissues in an obturator impression using an open palate impression tray is presented. The laboratory technique of obturator construction from this impression allows for a definitive (heat-cured) or interim (cold-cured) prosthesis for an edentulous or dentulous patient.

Dental Impression Technique↗
PubMed1987

Mandibular reconstruction using AO plates.

The AO plate represents an acceptable reconstructive choice for mandibular defects, with an 86.7 percent success rate demonstrated in this series. Because this method utilizes an alloplast which is precisely and quickly applied, virtually all patients requiring mandibular resection can be considered candidates for reconstruction. Adequate vascularized soft tissue coverage is essential to prevent plate extrusion and fistula formation. This is even more important for radiated patients. The pectoralis major myocutaneous flap provides muscle and skin for large anterior defects. Frequently, lateral defects can be closed primarily without using regional flaps. We suggest bone reconstruction to avoid potential plate fracture and to allow placement of functional dentures. Resections in elderly patients and for palliation will result in ideal cosmetic and functional results with the plate alone. If we exclude the four patients reconstructed with calcium hydroxyapatite and the AO plate, the morbidity rate is quite acceptable. With this group excluded, only four fistulas and eight plate exposures occurred. Only four plate removals were required to achieve wound closure. Evaluation of the titanium plate is in progress. It is hoped that better osseous and soft tissue integration will help to decrease wound complications. A large prospective review of postoperative radiotherapy patients using the new titanium plate has been designed to address this issue. The therapeutic choice between the AO plate and free vascularized bone graft reconstruction remains. The decision process is dependent on the technical skills of the surgeon, the treatment plan, the survival characteristics of the tumor, and the physiologic condition of the patient.

Bone Plates↗
PubMed1991

The frontonasal flap: utility for lateral nasal defects and technical refinements.

This report details the experience with 27 patients over a 5-year period who had nasal reconstruction using a frontonasal flap. The frontonasal flap procedure is a useful method for the repair of relatively large post-Mohs micrographic surgery defects of the lower, upper, lateral and central nose. Our modified method has been extended (1) to resurface lateral as well as central defects of the caudal one-third of the nose; (2) the scar can be shortened so it does not extend into the forehead; (3) the flap can be combined with the island nasalis flap, or nasolabial flaps to resurface large (3-4 cm) defects; (4) early dermabrasion has improved the scars in sebaceous skin.

Adult↗
PubMed2025

The RNA splicing factor PRPF8 is required for left-right organiser cilia differentiation and determination of cardiac left-right asymmetry via regulation of Arl13b splicing.

Cilia function in the left-right organizer (LRO) is critical for determining internal organ asymmetry in vertebrates. To further understand the genetics of left-right asymmetry, we isolated a mouse mutant with laterality defects, l11Jus27, from a random mutagenesis screen. l11Jus27 mutants carry a missense mutation in the pre-mRNA processing factor, Prpf8. cephalophŏnus (cph) mutant zebrafish, carrying a protein truncating mutation in prpf8, phenocopy the laterality defects of l11Jus27 mutants. Prpf8 mutant mouse and fish embryos have increased expression of an alternative transcript encoding the cilium-associated protein, ARL13B, that lacks exon 9. In zebrafish, over-expression of the arl13b transcript lacking exon 9 perturbed cilium formation and caused laterality defects. The shorter ARL13B protein isoform lacked interactions with intraflagellar transport proteins. Our data suggest that PRPF8 plays a prominent role in LRO cilia by through the regulation of alternative splicing of ARL13B, thus uncovering a new mechanism for cilia-linked developmental defects.

ARL13B↗
PubMed2026

Further Support for Association of DAND5 with Autosomal Recessive Laterality Disorders.

BACKGROUND: Laterality defects are rare congenital malformations that encompass congenital heart defects (CHDs) together with abnormalities of visceral organ arrangement (situs inversus or situs ambiguous). These defects may be isolated or part of a syndromic presentation with multisystem involvement. While over 50 genes have been implicated in laterality disorders, across multiple modes of inheritance, many cases remain molecularly undiagnosed. We sought to elucidate the molecular basis of dextrocardia, CHDs and visceral heterotaxy in two unrelated individuals of Arab-Muslim descent. METHODS: Detailed clinical phenotyping and exome sequencing (ES) were performed for each of the probands, followed by familial segregation analysis. RESULTS: ES revealed a shared homozygous variant in the Dan Domain Family Member 5 (DAND5) gene (NM_152654.3): c.396_397dup, p.(Tyr133SerfsTer11). DAND5 encodes a member of the Cerberus-related DAN protein family, which is involved in the establishment of left body asymmetry. This frameshift variant introduces a premature stop codon within the final exon, which is predicted to escape nonsense-mediated decay (NMD), resulting in a truncated protein lacking the functional DAN domain. CONCLUSIONS: DAND5 has recently been suggested as a candidate gene in heterotaxy and CHDs. Our findings further support biallelic loss of function variants in DAND5 autosomal recessive laterality defects.

Female↗
PubMed1987

A new twist to the nasolabial flap for reconstruction of lateral alar defects.

The nasolabial flap remains the favored technique for alar and lateral nasal reconstruction. Results with currently popular techniques tend to be inartistic and aesthetically disappointing. Improved results can be achieved, however, by a technique using a medially based nasolabial turnover flap for lining with a distal extension providing the cover. Reconstruction of the ala begins by designing a nasolabial flap with its base as close as possible to the site of the proposed ala. The flap is incised to the required margins, carrying 2 to 3 mm of underlying fat; then, hinged on its base, the flap is flipped over medially like the page of a book. As the proximal flap is sutured to the lining side of the defect, the distal flap gracefully twists 90 degrees and is then folded on itself to form the external surface of the ala. The donor site is closed primarily. With this procedure, a natural-appearing and appropriately positioned ala may be reconstructed in one step, although a second procedure may be helpful to sculpture the margin or precisely position the alar base.

Aged↗
PubMed1988

Correction of the unilateral cleft lip nose.

The cleft lip nasal deformity is best repaired secondarily in teenagers. Some more severe cases may be repaired during childhood. Optimal repair requires adequate exposure, best obtained with transcolumellar flying-bird incisions. The major anatomic defect, the misplaced lateral crus, needs to be advanced to a normal position. The vestibular lining of the lateral crus should remain attached to add circulation and support, especially when scoring of the cartilage is needed. The lateral defect left after advancement of the lateral crus should be closed with sutures. Accessory procedures, including septoplasty, augmentation or reshifting of the alar base attachment, and occasionally, cartilage grafts, are critical to achieving an aesthetic result. Fifty-three patients operated on using the technique described are reviewed.

Adolescent↗
PubMed1976

Repair of large chest wall defects using pedicle flaps.

Three cases of chest wall resection illustrate the use of three different full thickness pedicle flaps which can be used to cover almost any area of the anterior chest wall. The medially based acromiothoracic flap was swung inferiorly to cover a lateral defect. Laterally based abdominal wall and axillary flaps were used to cover more medial defects. In case III bilateral axillary flaps were necessary to cover a huge central defect after resection of the anterior sternum and anterior cartilages of seven ribs for a sebaceous carcinoma.

Aged↗