Search PubMed⌕ Search

Biomedical subjects

M Wickman

Publications and source records attributed to M Wickman.

At least 91 records · Page 5Linked to original sources

Immediate breast reconstruction: short-term experience in 75 consecutive cases.

Immediate breast reconstructions are being done more often nowadays to avoid the stress that the patient experiences while living without a breast. In this paper, the procedure and short term outcome of 75 patients who underwent immediate breast reconstructions at the Karolinska Hospital are reported. The median age of the patients was 48 years, and most of the tumours were stage O to 2 at the time of the operation, though reconstructions were also done for patients with more advanced cancer, for psychological reasons. The approach was multidisciplinary with oncologists, general surgeons, and plastic surgeons involved. Different reconstructive methods were used, and the operations were tailor-made for each patient. Twenty one permanent prostheses, 11 expanders, 33 expander prostheses, and eight pedicled and two free transverse rectus abdominis musculocutaneous (TRAM) flaps were used for reconstruction. The opposite breast was adjusted in 43 (57%) of the patients. There were 11 postoperative complications (15%), and in only one patient (1%), could the reconstruction not be completed. There was a tendency towards more complicated reconstructive procedures over time. The demand for immediate breast reconstruction is steadily increasing from both patients and doctors.

Adult↗

Skin thickness in expanded human breast skin.

By means of an ultrasonic technique, skin thickness was measured in 13 women subjected to mammary reconstruction by tissue expansion. Measurements were performed the day before introduction of the expander, after the last inflation, the day before introduction of the permanent implant, and at 2 weeks and 6 months after this operation. Five patients had their expanders inflated every day (rapid expansion), and 8 patients, once a week (slow expansion). A decrease in skin thickness during the inflation period was recorded, and this decrease was permanent even 6 months after the second operation. After exchange of the expander for a permanent implant, there was a transient statistically significant increase in skin thickness. There was no statistical difference between the groups of rapid and slow expansion.

Adult↗

Reduced mite allergen levels in dwellings with mechanical exhaust and supply ventilation.

Seventy similar bungalows constructed between 1968 and 1970 in the same suburban area of Stockholm were investigated regarding the content of house dust mite allergen, absolute indoor humidity, type of ventilation and basement construction. Houses with mechanical exhaust and supply ventilation had an indoor humidity above 7 g/kg less often than houses without this type of ventilation (Odds ratio 0.1, 95% confidence interval 0.0-0.2). Furthermore, only five of the 24 houses with exhaust and supply ventilation contained mattress dust mite allergen concentrations exceeding the median value (98.5 ng/g) compared with 30 of 46 hours which did not have such ventilation (odds ratio = 0.1, C.I. 0.0-0.5). Houses with both natural ventilation and crawl space basement harboured significantly less mattress mite allergen than houses having the same type of ventilation, but with a concrete slab basement. In a cold temperature climate, type of building construction and ventilation seem to be important for the occurrence of house dust mite allergens in dwellings. Our results indicate that modern energy-efficient houses should be equipped with mechanical exhaust and supply ventilation to reduce indoor air humidity during the dry winter months and the risk of mite infestation.

Air Pollution, Indoor↗

Mite allergens during 18 months of intervention.

In Stockholm, Sweden, 17 children with newly diagnosed sensitization to house-dust mites (HDM) and 11 children with previously diagnosed HDM-sensitization were included in a study of HDM-allergen avoidance. Mattress dust was collected on repeated occasions during 18 months and assayed for concentration of major HDM allergens. During the first 12 months, the parents of the intervention group were instructed to intensify cleaning and airing of the child's bedroom. During the last 6 months of the study, the mattresses and pillows of seven children in the intervention group and sibling controls were encased in semipermeable polyurethane covers. The homes exhibited a high absolute indoor humidity throughout the year, and even during the winter the mean levels exceeded 7 g/kg. No mite allergen reduction was seen in the intervention group during the first year. However, among the newly diagnosed HDM-sensitized children, there was a mean reduction of the mattress mite allergen concentration of 83% (P = 0.02), and this was most pronounced in the homes with low humidity. At the end of the mattress encasement period, an average difference of 98% (P < 0.001) was found between the vacuumed amount of mite allergen on top of the covers and that underneath.

Adolescent↗

Pedicled compared with free transverse rectus abdominis myocutaneous flaps in breast reconstruction.

Two groups of patients who had undergone breast reconstruction with the transverse rectus abdominis myocutaneous (TRAM) flap after modified radical or partial mastectomy were evaluated. The type of reconstruction was either pedicled (n = 27, one of which bilateral) or free flap transfer (n = 11). In both groups there were both primary and secondary reconstructions. Flap complications were more common with the pedicled TRAM flap. There were nine partial flap necroses in the pedicle group, but only one in the free flap group. The only flap loss was a pedicled flap. In the free flap group, revision of the anastomosis was required in two patients. The free TRAM flap took longer to do than the pedicled flap. In conclusion, the two procedures yield acceptable results, but the free TRAM flap seems to be safer than the pedicled flap, thanks to the better blood supply from the inferior epigastric artery. It also allows greater freedom and versatility in moulding the reconstructed breast.

Female↗

Mitotic activity in expanded human skin.

In 20 patients subjected to breast reconstruction by means of tissue expansion, a skin biopsy was obtained at the vertex of the breast before and the day after expansion. Samples were incubated in [3H]thymidine, and the number of labeled cells were counted. A statistically significant rise in the number of labeled basal and suprabasal keratinocytes was seen after expansion. The findings suggest a net gain of tissue not only by stretching but also by formation of new tissue generated by tissue expansion.

Biopsy↗

Sensitization to domestic mites in a cold temperate region.

Factors favoring sensitization to house dust mites (HDM) were studied in a cold, temperate climate in northern Sweden. Sixty-five children previously found to react positively to a skin prick test (SPT) to HDM were included. The SPT to HDM was repeated, and serum IgE antibodies to D. pteronyssinus and D. farinae were determined. HDM, Euroglyphus maynei, Tarsonemus, or storage mites occurred in mattress dust samples from 23 of the 65 homes, and in 10 homes more than 100 HDM/g of mattress dust were found. Mites were more prevalent in mattress dust from the basement and ground levels than from the upper floors. Sensitization to HDM was strongly with the presence of domestic mites in mattress and floor dust. Previous longer stays in southern Sweden or Europe were also associated with present sensitization to HDM, and this was independent of occurrence of mites in the residence. The results indicate that HDM growth and potential for sensitization in cold, temperate regions is highly dependent on the microhabitat, and that sensitization to HDM should be possible to prevent in such climatic regions.

Adolescent↗

A comparison of the capsules around smooth and textured silicone prostheses used for breast reconstruction. A light and electron microscopic study.

A total of 18 women who had undergone modified radical mastectomy and tissue expansion for breast reconstruction were studied. When the expanders were replaced, nine patients had received smooth, gel-filled permanent prostheses and nine had received textured, gel-filled permanent prostheses. For medical reasons, e.g. capsular contraction, incorrectly placed or sized implant, an additional operation was performed, and then biopsy specimens from the capsules around the prostheses were taken and subsequently examined with the aid of the light and transmission electron microscope (TEM). A histologist was able to classify blindly 11 capsules out of 13 which were investigated by light microscopy in the correct groups and several differences between the capsules were found. Capsules around the smooth implants had a clear line of separation between the inner surface and the prosthesis, and formed a single collageneous layer. They were sparse in fibroblasts, which were long and thin. Capsules around textured implants consisted of two layers, the outer layer being compact with long, slender fibroblasts, and the inner one looking rugged with wavy bundles of collagen often splitting from each other, and with shorter and more rounded fibroblasts. The overall thickness seemed greater compared to the capsules around the smooth prostheses, which, on the other hand, showed a greater variation in thickness. To analyze collagen fibril diameters, sample sections were photographed at magnification 22,000 x in the TEM. The fibril diameters were measured with an interactive image analysis system (IBAS). The mean diameter of the collagen fibrils was 47.2 nm in the capsules around the smooth prostheses and 51.7 nm in the capsules around the textured prostheses.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Comparison between rapid and slow tissue expansion in breast reconstruction.

Fifty women scheduled for breast reconstruction surgery with tissue expansion were randomly divided into two groups. In the first group the tissue was expanded rapidly, i.e., once a day, starting 1 week postoperatively, and in the other group it was expanded slowly, i.e., once a week, starting after 2 weeks. The expansion periods were 14 and 41 days, respectively. In both groups the expansion volume was about 200% of the final breast prosthesis. The expanders were replaced by textured, gel-filled implants after 3 months. Follow-up examinations were made after 6 and 12 months to evaluate breast softness. A subjective method, Breast Augmentation Classification, and an objective method, applanation tonometry, were used and showed good correlation. Subjectively, the capsular contraction rate after 1 year was 33.5% in the whole series: 40% in the rapid expansion group and 27% in the slow expansion group. Objectively, the capsular contraction rate was 50.5% in all patients: 60% in the rapid group and 41.5% in the slow group. There was no statistically significant difference between the two groups at any time with either method. Irradiated patients included in the study did not show poorer results. The results obtained after 6 months remained stable up to 12 months after the implantation of the permanent prosthesis. The importance of objective evaluation to compare different series is discussed.

Breast Neoplasms↗

Indoor viable dust-bound microfungi in relation to residential characteristics, living habits, and symptoms in atopic and control children.

Floor dust was collected in the wintertime from the homes of 61 children sensitized to house dust mites, 57 children with sensitization to other aeroallergens, and 57 nonatopic control children. The dust was cultivated and microfungal growth was identified microscopically. Indoor humidity was measured, and condensation on windowpanes was registered during 1 winter week. Housing and sociodemographic and symptom data were obtained by a questionnaire. Penicillium, Alternaria, and Cladosporium were the three most common microfungi. The mean total number of colony-forming units per 30 mg of dust was significantly lower in the homes of the two atopic groups than in homes of the control group, which may be a result of allergen-sanitation measures. High colony-forming unit counts appeared to be related to damp housing. Weak associations were found between the occurrence of viable fungi in dust and allergic symptoms among the house dust mite-sensitized children. However, no consistent association between viable mold growth and sensitization to molds was observed. The health implications of indoor fungal exposure still remain unclear.

Adolescent↗

Alterations in skin properties during rapid and slow tissue expansion for breast reconstruction.

This study comprises 23 women who had had mastectomies because of breast cancer. They were randomly divided into two groups when they were admitted for breast reconstruction by tissue expansion. The first group was expanded rapidly, i.e., every day, and the other group was expanded slowly, i.e., every week. There were no other differences in the treatment between the two groups. Three months after completion of expansion, the expander was replaced by a permanent prosthesis. The follow-up time was up to 6 months after the second operation. Three different parameters--distensibility, elasticity, and hysteresis--were measured noninvasively on the breast skin and at a control site on several occasions throughout the treatment. During the treatment period there were no differences in skin properties between rapidly and slowly expanded patients. Of the three parameters, distensibility showed the most prominent changes: decreasing during the expansion period, increasing after the expander had been replaced by a permanent prosthesis, and decreasing during the following 6 months. Elasticity did not change significantly, except decreasing after insertion of the permanent prosthesis, and the hysteresis increased at the same time. These findings indicate that tissue expansion alters breast skin only to a small extent and that the mechanical resistance sometimes encountered during tissue expansion is due to deeper structures such as underlying muscles or capsule formation.

Body Water↗

Dimensions of capsular collagen fibrils: image analysis of rapid compared with slow tissue expansion for breast reconstruction.

Thirty women who were to undergo breast reconstruction by tissue expansion were randomly divided into two groups. Those in the first group were to undergo expansion once a day (rapid expansion) and the second group once a week (slow expansion). When the expanders were replaced by permanent prostheses, biopsy specimens were taken from the capsules around the expanders, and were examined by transmission electron microscopy at a magnification x 22,000. The diameters of the collagen fibrils in the capsules were analysed by an interactive image analysis system and measured. An analysis of variance was performed on a test series to optimize the sample. Ninety fibrils from each patient (two patients were excluded), were analysed and there were no significant differences in collagen fibrillar diameters (about 50 nm) between those who had undergone rapid or slow expansion, or between patients who had also undergone radiotherapy to the chest wall and those who had not. These results indicate that the collagen fibrils may still be in a transitional stage, and that further longer term studies are desirable. It is difficult, however, to see how they could be justified ethically in patients who are otherwise well.

Adult↗

House dust mite sensitization in children and residential characteristics in a temperate region.

House dust mite (Hdm) infestation used to be rare in Stockholm, but Hdm-sensitized children are now frequently observed, which probably indicates an increased infestation rate. This study was performed to elucidate determinants of Hdm sensitization in children living in the area. In a case-control study, 53 Hdm-sensitized children (cases), a group of non-Hdm-sensitized atopic children (N = 54), and a group of nonallergic neighborhood children (N = 53) were included. Mattress dust was analyzed with ELISA for content of Hdm allergens. Indoor humidity and temperature were measured, and questionnaire data were collected. Asthma was significantly more common in the Hdm-sensitized group than in the atopic control group. Hdm allergens were found in 40%, 19%, and 23% of the dust samples of the case group, atopic group, and neighborhood control groups, respectively. Only 15% of the dust samples of the Hdm-sensitized children contained Hdm allergens above the recommended threshold levels of sensitization of 2000 ng/gm of dust. Inadequate ventilation, which partly appeared to be a consequence of energy saving, appeared to be a risk factor for Hdm sensitization. This result may apply also to other temperate regions and suggests that the problem is preventable.

Adolescent↗

Circulatory and metabolic changes in expanded pig skin flaps.

To evaluate circulatory and metabolic changes in pig skin during tissue expansion, the buttock skin of 12 pigs was expanded for 5 weeks. In a second operation, island buttock flaps were elevated bilaterally. Flap temperature, laser Doppler flow (LDF), and fluorescein penetration borders were recorded. Norepinephrine infusions were given twice. After cannulation of the external iliac veins, the total venous outflow from the flaps and metabolic parameters such as glucose and oxygen consumption and lactate production were measured bilaterally. No significant difference in fluorescein staining was found, but laser Doppler flow in the expanded tissue was higher than in nonexpanded skin, whereas the total flap blood flow was not significantly different. A flow reduction was seen in expanded flaps during norepinephrine infusion, whereas nonexpanded flaps showed a slightly increased blood flow. This adrenergic supersensitivity indicates that it is possible that not only surgical nerve section but also tissue expansion can result in sympathetic denervation. No differences in the metabolic parameters were observed.

Animals↗

Metronidazole treatment of liver abscess due to bacteroides fragilis.

A 67-year-old woman with a liver abscess due to Bacteroides fragilis was treated with metronidazole 0.4 g orally every 8 h for 6 weeks. There was a rapid clinical improvement even though no surgical drainage was performed. By the indirect immunofluorescence technique using the patient's own strain as an antigen the antibody titer declined from 5120 to 80 in 6 months, suggesting eradication of the infecting agent.

Administration, Oral↗