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Biomedical subjects

R E Nordström

Publications and source records attributed to R E Nordström.

At least 19 recordsLinked to original sources
PubMed1999

Serial scalp reductions: a biomechanical approach.

BACKGROUND: Several technical aspects of scalp-reduction procedures still need to be clearly elucidated: in particular, (a) the quantitative effects provided by different amounts of subgaleal undermining, (b) the immediate gains provided by increasing amount of tension when advancing a scalp flap, and (c) the eventual benefits provided by galeotomies. OBJECTIVE: The aim of the present paper is to report on some biomechanical properties of scalp flaps as related to serial scalp reduction procedures for correction of male pattern baldness. METHODS: Data were collected by stepwise loading of 20 scalp flaps, obtained by a reversed-Y scalp incision, after increasing amounts of undermining, as well as after performing three galeotomies. RESULTS: Increasing amounts of tension (while advancing a scalp flap) affect the compliance of a scalp flap in a non-linear fashion; increasing amounts of undermining permit obtaining significant, but not proportional, gains; performing galeotomies is a useful adjunct to decrease the amount of closing tension when performing scalp-reduction procedures. CONCLUSION: When performing serial scalp reductions, to take into account the biomechanics of scalp flaps may be of some utility in obtaining an optimal result.

Adult↗
PubMed1999

Scalp extension--a quantitative study.

The authors have compared the results of scalp reductions with extenders with their earlier results of scalp reductions without extenders. The extenders seem to prevent "stretch-back" and provide 30 to 86% more effectiveness when a second reduction is performed 4 weeks later.

Alopecia↗
PubMed1999

Effects of cooling micrografts in hair transplantation surgery.

BACKGROUND: When isolating hair grafts in hair transplantation procedures, it is generally recommended to preserve the grafts at a low temperature (1 degrees C- 4 degrees C) in order to enhance the survival rate of the grafted hairs. This study was carried out to test the real benefits provided by cold-storing hair grafts. OBJECTIVE: The aim of this study was to evaluate, in an in vitro model, the effects of cooling micrografts during hair transplantation procedures to experimentally assess the soundness of this approach to enhance the survival and growth rates of hair micrografts. METHODS: A total of 240 anagen hair follicles were obtained from 10 healthy male patients. Follicles were thus randomly assigned to one of the following groups: group A (control; n = 120 follicles), or group B (experimental; n = 120 follicles). Follicles from group A were preserved for 5 hours at room temperature (26 degrees C), and follicles from group B were preserved for 5 hours at 1 degrees C. Immediately after that 5-hour period, follicles from both groups were then cultured for 10 days. The length of each follicle was measured immediately following the 5-hour test period and at the end of the 10-day culture period. RESULTS: No statistically significant differences were found between the survival and growth rates of follicles from the control (survival rate = 87%, mean 10-day growth rate = 2.68 mm) and experimental (survival rate = 88%, mean 10-day growth rate = 2.54 mm) groups. CONCLUSION: Although, at present, it is generally assumed that lowering the metabolism of grafts by reducing their temperature may be of some utility for enhancing their survival rate, our data indicate of that there are no effects when performing hair transplantation surgery.

Adult↗
PubMed1998

Effects of galeotomies on scalp flaps.

The aim of the present study was to evaluate how much a relaxing incision of the galea aponeurotica affects the biomechanical properties of a scalp flap to quantify the surgery-related advantages provided by this procedure. Twenty scalp flaps, created by a reverse-Y incision down to and through the galea aponeurotica together with undermining (in the layer between the galea and the pericranium) to within 1 cm of the external auditory canal were studied. Data were collected by stepwise loading the scalp flaps before and after performing three full-thickness galeotomies lengthwise and parallel to the sagittal scalp incision. The tension/ extension ratio characteristics were computed, and loading curves as well as mean stiffness values were measured. A statistically significant difference (-16.6 g per millimeter) was found between the slope (computed as Young's modulus) of the curves obtained before and after performing the galeotomies. This value corresponded to a mean 40% reduction of the closing tension attained with each galeotomy. In the closing-tension interval 500 g to 1,500 g, the mean gain of length of the flap per galeotomy was 1.67 mm. These data confirm the usefulness of galeotomies for lengthening the scalp flaps and for diminishing the tension on wound margins when closing scalp defects.

Adult↗
PubMed1998

Undermining of the scalp: quantitative effects.

The aim of the present study was to evaluate to what extent undermining affects the closing-tension of scalp defects to quantify the surgery-related benefits provided by this procedure. Data were collected by stepwise loading in 10 patients, 20 scalp flaps (obtained by a reversed Y scalp incision), and three different degrees of subgaleal undermining (1, 5, and 15 cm). The obtained data confirmed the value of undermining to diminish the tension on wound margins when closing a scalp defect. There was a progressive decrease in tension required to advance the wound edge when the amount of undermining was sequentially increased. Most of this reduction occurred with the 5-cm undermining, although statistically the 15-cm undermining also resulted in a significant decrease in the tension required to close the defect. Mean 83.3- and 92.2-percent reductions of the closing tension were obtained with 5 cm and 15 cm of undermining, respectively, compared with that achieved by the 1-cm undermining with the same width of defect.

Adult↗
PubMed1998

Follicular bisection in hair transplantation surgery: an in vitro model.

The aim of this study was to evaluate, in an in vitro model, the survival and growth rates of transversely sectioned human hair follicles to assess experimentally the soundness of this approach as a future possible method for "duplicating" available donor hair grafts in hair transplantation procedures. A total of 300 human anagen hair follicles was obtained from 10 healthy male patients. Follicles were thus randomly assigned to one of the following groups: group A (control; n = 100 follicles), cultured intact as dissected, and group B (experimental; n = 200 follicles), transversely transected, parallel to the epidermal surface and immediately below the bulge area, to obtain 200 lower-half follicles and 200 upper-half follicles. Isolated hair follicles from both groups were maintained in culture for 10 days. The length of each follicle was measured immediately following isolation and at the end of the 10-day culture period. No statistically significant differences were found between the growth rate of intact follicles (mean 10-day growth rate = 2.71 mm) and of lower-half follicles (mean 10-day growth-rate = 2.64 mm), whereas a statistically significant difference was found between the growth rate of follicles from the two above-mentioned groups and the growth rate of the "upper-half" follicles (mean 10-day growth rate = 1.07 mm). Histologic analysis demonstrated that both intact and lower-half follicles maintained a normal histologic appearance, whereas in upper-half follicle sections we invariably detected a region of intense cell proliferation, reminiscent of a regenerated follicular papilla, surrounding the lowermost part of the follicle. In our opinion, the reported in vitro survival rate of transected human hair follicles might represent an interesting starting point in striving to augment the number of donor hairs available during a hair transplantation procedure.

Adult↗
PubMed1998

Endoscopic transthoracic dorsal sympathectomy for the treatment of upper extremity hyperhidrosis: a new minimally invasive approach.

Palmar and axillary hyperhidrosis are best treated surgically by endoscopic transthoracic upper dorsal sympathectomy. At present, this methodology relies on (at least) double trocar insertion (per side), carbon dioxide insufflation, or both. We present a new minimally invasive endoscopic transthoracic technique, performed by a single-entry specifically modified thoracoscope and without the need for carbon dioxide insufflation, with the aim to reduce the drawbacks associated with the above-mentioned, currently adopted endoscopic technique. In our opinion, this "single-entry" technique, compared with the other reported approaches, should theoretically minimize any damage to the intercostal neurovascular bundle, while avoiding the complications related to carbon dioxide insufflation.

Adolescent↗
PubMed1998

Anchoring galeal flaps for scalp reduction procedures.

This article describes an operative technique, based on the use of three anchoring galeal flaps, aimed at reducing the percentage of "stretch-back" that occurs after performing scalp reduction procedures. In 12 male patients undergoing a midline scalp reduction procedure, three rectangular (2 x 3 cm) galeal flaps in direct continuity with the longitudinal margin of the left scalp flap were sutured individually to the galeal undersurface of the right scalp flap to draw the two scalp flaps toward the midline of the scalp and to relieve the wound margins of closing tension. Tattoo marks were placed on the patient's scalp at the level of the vertical lines drawn through the external auditory meatuses (A1-A2) and 6 cm more posterior (B1-B2) to measure the movement and stretching of the scalp. The results were compared with those obtained from a control group of 13 male patients who underwent the same surgical procedure but without the use of the anchoring galeal flaps. Mean stretch-back (as measured 4 weeks postoperatively) at level A1-A2 was 8.3 mm in the control group and 1.6 mm in the experimental group. The mean stretch-back at level B1-B2 was 7.7 mm in the control group and 0.9 mm in the experimental group. A statistically significant difference (p < 0.005) was found between data from the control and experimental groups regarding the above-reported stretch-back values at both levels. The use of the described galeal flaps allowed us to obtain an 80.93-percent and an 88.09-percent stretch-back reduction at levels A1-A2 and B1-B2, respectively, 1 month postoperatively.

Adult↗
PubMed1998

Rhomboid minigrafts in hair restoration surgery.

BACKGROUND: The transplantation of large numbers of three- to five-hair minigrafts has superseded the use of traditional punch grafts in hair restoration surgery. The minigrafts are usually designed and cut in a square or rectangular shape for implantation into the recipient slits. Transplanting a large number of these grafts into the recipient slits can lead to a high frequency of complications, especially in cases in which there is a need for dense packing of grafts. The complications include excess graft compression resulting in extrusion or retraction into the slit. This in turn can lead to piggybacking or insertion of two grafts per slit with the resultant effect of cyst formation, cobblestoning, and hypertrophic scar formation. OBJECTIVE: To develop an optimal shape of minigrafts to match the recipient slits. METHODS: The authors have calculated the optimum geometric configuration for a minigraft in a linear slit and have developed the correct cutting instrument and preparation technique for its production. This rhomboid minigraft design maximizes the graft stability in the slit and therefore its survival, and also minimizes the risk of complications. RESULTS: The described technique shows that the transplanted rhomboid minigrafts remain well anchored in the recipient slits and results in an excellent clinical outcome. CONCLUSION: The rhomboid minigrafting technique (1.5 x 1.5 mm in size) seems to accommodate the grafts better into the recipient slits than the standard shape rectangular minigrafts. It thereby better facilitates the insertion of the grafts in the slits and reduces the frequency of graft extrusion as well as graft compression.

Adult↗
PubMed1998

Power boosting the grafts in hair transplantation surgery. Evaluation of a new storage medium.

BACKGROUND: When performing hair transplantation procedures, it is of the foremost importance to try to obtain the maximum survival rate possible of transplanted micrografts. OBJECTIVE: Aim of this study was to evaluate, in an in vitro model, the effects of preserving micrografts, for five hours, in an enriched storage medium in order to enhance the survival rate of hair micrografts. METHODS: A total of 200 human anagen hair follicles was obtained from ten male patients. Follicles were thus randomly assigned to one of the following group: Group A (control; n = 100 follicles), preserved for five hours in saline, and Group B (experimental; n = 100 follicles), preserved for five hours in a storage medium, containing adenosine triphosphate-magnesium chloride and deferoxamine mesylate. Isolated hair follicles from both Groups were then cultured for 10 days. RESULTS: A statistically significant difference was found between the survival rate of experimental (98%) and control follicles (87%). CONCLUSION: In our opinion, a "metabolic preconditioning" of micrografts by means of storing them for 5 hours in the described medium may be of some utility in augmenting the survival rate of hair grafts when performing hair transplantation surgery.

Adenosine Triphosphate↗
PubMed1997

Tension and flap advancement in the human scalp.

The aim of the present study was to evaluate quantitatively the change in stiffness of scalp flaps determined by increased loads of tension. Data were collected by stepwise loading 20 scalp flaps, created by a reversed-Y incision down to and through the galea aponeurotica together with undermining. In the layer between the galea and the pericranium, to within 1 cm of the external auditory canal. The biomechanical properties of the tested scalp flaps were significantly influenced by increased extents of tension. The tissue's stress response to displacement was visualized as a three-phase characteristic. Initially linear (indicative load range, 0 to 500 g), the scalp's compliance gradually reduced (indicative load range, 500 to 1,500 g) and eventually demonstrated an exponential stress/strain characteristic of rapidly increasing stiffness (indicative load range, 1,500 to 5,000 g). The Young's modulus, E, of the stress/strain curve was found to be equal to 49.2 g per millimeter. The obtained data suggest that a reasonable approach should consist of closing a scalp defect within the tension range of 500 to 1,500 g. This will take full advantage of the plasticity of the scalp flap. The gain obtained with a closing tension above this range would be minimal, with a presumably increased complication rate.

Adult↗
PubMed1997

Standardized technique of transplanting micrografts in hair restoration surgery. A practical approach.

BACKGROUND: The transplantation of a large number of hair-bearing micrografts has become an important method in hair restoration surgery and one that achieves a more natural looking growth of the transplanted hairs than minigrafts or punchgrafts. However, the process of grafting over a hundred micrografts is still tedious, laborious, and time-consuming, and also increases the amount of surgical trauma to the hair follicles of the donor site. OBJECTIVE: To speed up the process of micrografting and minimize surgical trauma to the follicles and the grafts in order to maximize the grafts survival and therefore optimize clinical results. METHODS: The authors describe the standardized micrografting technique used in our unit for hair transplantation, which speeds up the grafting process and minimizes the trauma due to surgery during the various fares of the transplanting procedure of the hair follicles. RESULTS: The described technique significantly speeds up the process of transplanting micrografts with minimal surgical trauma and therefore the best possible graft survival. CONCLUSION: Standardized micrografting is a fast, practical and efficient technique for hair restoration surgery.

Adult↗
PubMed1997

Minigraft preparation in surgical hair replacement.

A 38-year-old man with Norwood type V male pattern baldness underwent hair restoration surgery using a new technique aimed to minimise the time spent on cutting minigrafts by using a multibladed knife. A total of 600 minigrafts were harvested from the occipital region, prepared, and inserted into the bald area. This method significantly enhances the rate of minigraft preparation during hair transplantation procedures, as dividing minigrafts from hair-bearing strips of scalp using a multibladed knife simplifies the whole cutting session. Furthermore, grafts prepared with the multibladed scalpel are more regular in size than those obtained with the traditional technique.

Adult↗
PubMed1996

An unusually avulsed penis successfully replanted by using microsurgical technique.

An unusually avulsed penis and its successful microsurgical replantation is reported. The penis was self-avulsed between the superficial fascia of the shaft, and the shaft was cut distally, just proximal to the glans, with the whole glans and a short part of the shaft hanging in the avulsed skin of the penis. According to our search in the literature, this is the first successful replantation of such a case by microsurgery. The blood circulation of the replant was reestablished, after 15 hours of tissue ischemia, by means of microsurgical vascular anastomosing of the minimal subcutaneous vessels in the skin. Both the skin and the glans survived, indicating the alternative possibility of replantation of avulsed penile skin by microsurgery, rather than by skin grafting.

Adult↗
PubMed1996

Cleft-twin sets in Finland 1948-1987.

Extensive review of the literature since 1884 on cleft-twin sets yielded 364 cleft-twin sets. Of these, 118 were monozygotic (MZ) and 246 dizygotic (DZ) sets. In addition, Danish material on cleft twins, like our Finnish material, reflects the total number of clefts and cleft twins on a well-defined population during a well-defined time interval. Both sets of material also contain slightly over 100 pairs of twins. The Danish material and the literature review were compared to the Finnish material. The hospital records of all Finnish patients with operated clefts who were born between 1948 and 1987 were reviewed. Information was gathered regarding each patient, his parents, the pregnancy, and his twin or triplet siblings and other siblings. This search produced 105 sets of twins and three sets of triplets with clefts, 15 sets of twins being concordant regarding clefting. This resulted in a total of 120 cleft siblings, and the corrected cleft incidence of 1.72 promille, close to the overall cleft incidence rate in Finland between 1948 and 1975. Twinning was found to be associated neither with an increased nor with a decreased risk of clefting, and clefting could not be seen to increase twinning. Zygosity could be verified in 88 sets of twins; the total number of MZ sets was 17, and of DZ was 71, a 19% MZ rate. Although a higher incidence of clefting in MZ-twin sets has been proposed, no such higher or lower incidence could be found in our material. Recognized syndromes were found in 15 sets (14%), slightly higher than found in a large Finnish study on cleft probands (8.4%). Of these, three sets were monozygotic (MZ), all of them cleft palate (CP) and male sets, whereas eight sets were dizygotic (DZ). All 15 sets were CP only, with no one set with cleft lip and palate [CL(P)]. In our total Finnish-twin material of 105 sets, we found the CL(P)/CP ratio to be 39/66 (37%/63%). In all of the 120 affected siblings, the ratio was 35%/65%. The very high rate of 63% of CP twins is about two to three times higher than that reported in the literature of 364 sets where the CP ratio is 23%; compared to the Danish material with a CP ratio of 17%, it is almost four-fold. The overall CP rate in all clefts (not restricted to twins) in Finland compared to the rate in our neighboring Scandinavian countries was very much in line with this very big difference seen in the CP rate in our twin material. The CL(P) incidence in our Finnish material is 0.61 promille and the CP incidence 1.11 promille. For MZCL(P), the incidence was 0.38 promille; for MZCP, 0.91 promille; for DZCL(P), 0.52 promille, and for DZCP, 0.99 promille. Compared to the Danish figures both the MZCP and DZCP incidence figures are nearly four-fold, with the MZCL(P) somewhat lower, and DZCL(P) less than half that number. The sex distribution of all cleft patients in our material was 44% male/56% female. Both in the Danish material and in the literature, it was the reverse. This difference is probably due mostly to the higher ratio of CP in the Finnish material. The CP group has a higher proportion of females in all these materials. The concordance (C) of the whole Finnish-twin material is 14%, compared to 16.5% reported in the literature and 8% for the Danish twins. The concordance for CL(P) in our material is many times lower (2.6%) than in the literature (17.1%) and in the Danish material (8%). In the Finnish twins, the C for CP is higher (17%) than that for the Danish (6%) and for the literature cleft-twin populations (14.3%). This is also true for the MZ and DZ subgroups. The heritability index (H) in CL(P) is lower for the Finns (17%) than for the Danish (45%) and for the literature materials (43%), and higher for CP (Finns 49%, Danish 33%, literature 36%). All of these data strongly suggest the quite different genetic behavior of both CL(P) and CP in Finland, with a much lower genetic component in the CL(P) and a higher in the CP.

Cleft Lip↗
PubMed1996

External device for tissue expansion: clinical evaluation of the skin extender.

Tissue expansion is a well known way of repairing soft tissue defects. However, traditional tissue expanders have certain disadvantages such as the need for repeated outpatient visits for the filling of the expander and a long period of time required before the final result is achieved. A series of other devices have recently been developed. We have evaluated one of these, a skin extender developed by Blomqvist and Steenfos, in 10 lesions of the extremities in nine adult patients. The defects ranged from 3.5-10 cm wide and the extenders were inserted under local anaesthesia. The patients were taught how to tighten the extenders themselves, so there was no need for repeated visits to the outpatient department. Nine of the 10 defects were excised within 14 days; the remaining one developed a wound infection. The results show that this skin extender is a simple, fast, and economical device for repairing soft tissue defects, and in certain cases it is more suitable than a traditional tissue expander. Its major drawback is unsightly scars in the normal skin beside the previous defect.

Adult↗