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At least 379 records · Page 21Linked to original sources

PubMed2005

[Risk factors for acute abdominal wall dehiscence after laparotomy in adults].

INTRODUCTION: Total evisceration consists of protrusion of the abdominal viscera due to dehiscence of all the planes of the abdominal wall after laparotomy. The greater the number of risk factors, the greater the probability of evisceration. PATIENTS AND METHOD: We performed a retrospective study of patients with evisceration treated in the previous 9 years. RESULTS: Among 12,622 patients who underwent laparotomy, 57 eviscerations were detected (45 men, 12 women; mean age 70 years). The diagnosis was peritonitis in 26 patients and intestinal occlusion in 19. Emergency surgery was performed in 48 patients. Reintervention was performed in 12 patients. Postoperative complications were found in all patients, especially wound infection and paralytic ileus. The main clinical finding was staining of the dressing. Laboratory investigations revealed leukocytosis, hypoproteinemia, and anemia. Surgical repair consisted of simple closure and/or retention sutures; mesh was associated in 6 patients. Subsequent morbidity was 77%. Twenty-six patients required admission to the intensive care unit. The mean length of hospital stay was 28.5 days. The were 41 recoveries (72%) and 16 deaths (28%). Review of 18 parameters involved in evisceration showed that 80% (45 patients) presented 9 or more risk factors. CONCLUSIONS: Evisceration is a serious occurrence that produces high morbidity and mortality. The most frequent risk factors in our series were age greater than 65 years, hemodynamic instability, increased intra-abdominal pressure, emergency surgery, infection of the wound or abdominal wall, hypoproteinemia and anemia. Because these risk factors can be predicted, when several are grouped together, reinforcement should be used when closing the abdominal wall.

Abdominal Wall↗

PubMed2005

MDCT of abdominal wall hernias: is there a role for valsalva's maneuver?

OBJECTIVE: Our objective was to evaluate the role of Valsalva's maneuver during MDCT for the diagnosis and characterization of abdominal wall hernias. SUBJECTS AND METHODS: From September 2002 to May 2003, 100 consecutive patients (37 men and 63 women; mean age, 53 years) with suspected anterior abdominal wall hernias underwent 4-, 8-, or 16-MDCT with and without Valsalva's maneuver. Patients received both oral and IV contrast material. On a workstation, three independent reviewers evaluated each scan obtained during rest and during Valsalva's maneuver for the following parameters: anteroposterior (AP) diameter of the abdomen; presence, location, and contents of the hernia; and transverse diameter of the fascial defect. The scans were compared to assess for changes in hernia size and contents and to determine whether the hernia would have been overlooked without Valsalva's maneuver. Fisher's exact test, the McNemar test, and Cohen's kappa coefficient were used to assess for significant differences. RESULTS: The three reviewers identified a mean of 72 abdominal wall hernias (72%). The reviewers agreed (kappa = 0.723) with respect to the presence of a hernia. AP diameters increased an average of 1.33 cm during Valsalva's maneuver (p < 0.001). The transverse diameter of the fascial defect increased an average of 0.66 cm and the AP diameter of the hernia sac increased an average of 0.79 cm during Valsalva's maneuver (p < 0.001). Fifty percent of the hernias became more apparent with Valsalva's maneuver. Ten percent of the hernias could be detected only on the scan obtained during Valsalva's maneuver. Conversely, in no patients was the hernia detected only on the rest scan. CONCLUSION: As opposed to scans obtained at rest, scans obtained during Valsalva's maneuver aid in the detection and characterization of suspected abdominal wall hernias. A single scan obtained during Valsalva's maneuver is sufficient to detect 100% of anterior abdominal wall hernias identified on CT.

Adult↗

PubMed2000

Complex abdominal wall reconstruction: a comparison of flap and mesh closure.

OBJECTIVE: To analyze a series of patients treated for recurrent or chronic abdominal wall hernias and determine a treatment protocol for defect reconstruction. SUMMARY BACKGROUND DATA: Complex or recurrent abdominal wall defects may be the result of a failed prior attempt at closure, trauma, infection, radiation necrosis, or tumor resection. The use of prosthetic mesh as a fascial substitute or reinforcement has been widely reported. In wounds with unstable soft tissue coverage, however, the use of prosthetic mesh poses an increased risk for extrusion or infection, and vascularized autogenous tissue may be required to achieve herniorrhaphy and stable coverage. METHODS: Patients undergoing abdominal wall reconstruction for 106 recurrent or complex defects (104 patients) were retrospectively analyzed. For each patient, hernia etiology, size and location, average time present, technique of reconstruction, and postoperative results, including recurrence and complication rates, were reviewed. Patients were divided into two groups based on defect components: Type I defects with intact or stable skin coverage over hernia defect, and Type II defects with unstable or absent skin coverage over hernia defect. The defects were also assigned to one of the following zones based on primary defect location to assist in the selection and evaluation of their treatment: Zone 1A, upper midline; Zone IB, lower midline; Zone 2, upper quadrant; Zone 3, lower quadrant. RESULTS: A majority of the defects (68%) were incisional hernias. Of 50 Type I defects, 10 (20%) were repaired directly, 28 (56%) were repaired with mesh only, and 12 (24%) required flap reconstruction. For the 56 Type II defects reconstructed, flaps were used in the majority of patients (n = 48; 80%). The overall complication and recurrence rates for the series were 29% and 8%, respectively. CONCLUSIONS: For Type I hernias with stable skin coverage, intraperitoneal placement of Prolene mesh is preferred, and has not been associated with visceral complications or failure of hernia repair. For Type II defects, the use of flaps is advisable, with tensor fascia lata representing the flap of choice, particularly in the lower abdomen. Rectus advancement procedures may be used for well-selected midline defects of either type. The concept of tissue expansion to increase both the fascial dimensions of the flap and zones safely reached by flap transposition is introduced. Overall failure is often is due to primary closure under tension, extraperitoneal placement of mesh, flap use for inappropriate zone, or technical error in flap use. With use of the proposed algorithm based on defect analysis and location, abdominal wall reconstruction has been achieved in 92% of patients with complex abdominal defects.

Abdominal Muscles↗

PubMed1997

[Anatomy of the abdominal wall--an area at risk for hernias].

The muscles as well as the fibrous elements of the abdominal wall will alter their function in man due to his upright position, although the abdominal wall's architecture remains ancestrally. The abdominal muscles quit the only function of visceral weight bearing; they are now additionally important for trunk movements and the stabilisation of the vertebral column. Bipedalism leads to a special intraabdominal pressure distribution, predetermining the more caudal regions of the abdominal wall to herniation.

Abdominal Muscles↗

PubMedDate not supplied

[The use of prosthetic materials placed intraperitoneally in the repair of large defects of the abdominal wall, reflections on a limited case series].

To evaluate the best prosthetic material in direct contact with intestinal loops in the repair of large abdominal wall defects, four cases were reevaluated and an extensive review of the literature was undertake to point out the pathophysiology of prosthetic materials in abdominal wall surgery. For its intrinsic features, Gore-Tex represents the best prosthetic material to locate intraperitoneally, but the slow foreign body reaction is responsible for postoperative complications (e.g. hematoma, seroma, dehiscence). Marlex should not be used in direct contact with intestine because of the risk of multiple fistulas, very difficult to treat, while, the intense foreign body reaction rapidly integrate the mesh into the abdominal wall. To treat large abdominal wall defects are now been proposed mixed prostheses (Gore-Tex in intraperitoneal location, Marlex at the exterior) and dual mesh Gore-Tex (two textures at different microporosity on each side of the mesh). Preliminary studies have shown the safety and utility of these prostheses.

Abdominal Muscles↗

PubMed1999

What comprises appropriate therapy for children/adolescents with rhabdomyosarcoma arising in the abdominal wall? A report from the Intergroup Rhabdomyosarcoma Study Group.

PURPOSE: The aim of this study was to define clinical features and determine the best therapy for patients with rhabdomyosarcoma (RMS) of the abdominal wall. METHODS: We examined the demographic, clinical features, therapy (especially surgical), and outcome of 34 patients. Patients received combination chemotherapy after complete surgical resection (group I, n = 14; 41%); resection with microscopic residual followed by local irradiation (RT; group II, n = 8; 24%); partial resection or biopsy only plus RT with gross locoregional residual tumor (group III, n = 4; 12%); or biopsy only plus RT with metastatic disease (group IV, n = 8; 24%). Patients with group I or group II tumors had undergone partial abdominal wall resection (ie, involved muscle only with preservation of peritoneum, n = 11) or complete abdominal wall resection (n = 7). Four additional patients had groin lesions. RESULTS: Thirty-four children or adolescents with abdominal wall RMS (about 1% of all patients) were treated on Intergroup Rhabdomyosarcoma Study I (IRS-I) through IRS-IV. Overall, adolescents comprised 14 of 34 eligible patients (41%), and 10 of 14 (71%) adolescents had alveolar or undifferentiated tumors versus 8 of 20 (40%) younger children (P= .07). Failure-free survival (FFS) rate and survival rate at 5 years was 65%. Treatment outcome was poorer for patients with group III-IV tumors (P = .01), adolescents (P = .09) and patients with alveolar or undifferentiated sarcomas (P = .12). CONCLUSION: Patients with localized tumors appear to fare better if they undergo complete abdominal wall resection (long-term survival rate, 100%) versus partial resection (long-term survival rate, 62% [P = .12]).

Abdominal Muscles↗

PubMed1998

The prune-belly syndrome: a new and simplified technique of abdominal wall reconstruction.

PURPOSE: Various techniques of reconstruction have been developed to improve the cosmetic and functional status of the abdominal wall in the prune-belly syndrome. We describe a new extraperitoneal plication technique of abdominoplasty that is simplified in comparison to other established procedures in that it obviates the need for a fascial incision and/or entrance into the peritoneal cavity in patients who do not require a concurrent intra-abdominal procedure. MATERIALS AND METHODS: Since 1980 this technique of abdominoplasty has been performed in 13 patients 9 months to 11 years old (mean age 3.8) at 2 institutions. Seven patients underwent surgery before age 2.5 years. Abdominal wall reconstruction was performed as an isolated extraperitoneal procedure in 5 patients, while 8 had concomitant procedures performed with the abdominoplasty, including bilateral Fowler-Stephens orchiopexy in 7, ureteral reconstruction/reimplantation in 5, excision of urachal diverticulum or cyst in 2, reduction cystoplasty in 1 and Tenckhoff catheter placement in 1. RESULTS: In all cases the cosmetic result was excellent and satisfactory to patients, parents and surgeons. Since the first procedure was performed 17 years ago, only 1 patient has returned with abdominal wall laxity or bulging in the area of repair. CONCLUSIONS: Our method of abdominal wall reconstruction in the prune-belly syndrome produces a cosmetically excellent and durable result. In contrast to other techniques of abdominoplasty, the need for a fascial incision and/or entrance into the peritoneal cavity is avoided. We believe that this modified procedure offers distinct technical and anatomical advantages over other existing techniques.

Abdominal Muscles↗

PubMed1990

[Abscess of the abdominal wall following penetration of the descending colon: a rare complication of a ventriculoperitoneal shunt].

A case of abscess of the abdominal wall associated with a ventriculoperitoneal (V-P) shunt following penetration into the descending colon is reported. A 49-year-old male was diagnosed as having hypertensive intracerebellar hematoma with hydrocephalus, and he was treated by V-P shunt. One year later he experienced left hypochondrial pain with rebound tenderness during a period of one week. He was doing well until 4 years and 10 months after, when barium enema examination and colonoscopy incidentally demonstrated that the abdominal catheter had penetrated into the descending colon. However, he had no symptoms. He remained in good health during a period of observation. A year later he was readmitted to our department with an abscess of the abdominal wall. Plain radiograph of the abdomen demonstrated disconnection of the shunt catheter and it was thought that the abdominal catheter had been passed via the rectum. At operation a subcutaneous abscess was found and cultures grew proteus mirabilis. We discussed the mechanism of the developing of the abscess on the abdominal wall following penetration of the bowel. It is believed that abscess of the abdominal wall may occur due to spontaneous extraction of a previously inserted shunt catheter which has penetrated into the bowel.

Abdominal Muscles↗

PubMed1990

The effect of parenteral nutrition on the healing of abdominal wall wounds and colonic anastomoses in protein-malnourished rats.

The effect of postoperative parenteral nutrition on the healing of abdominal wall wounds and colonic anastomoses in protein-malnourished rats was studied. The healing of laparotomy wounds and colonic anastomoses was assessed by bursting pressure measurement on the fifth postoperative day. Compared with control animals on a normal diet (group A), rats on a low-protein diet given postoperative dextrose-saline solution (group B) had significantly lower abdominal wall and colonic anastomotic bursting strengths. The detrimental effects of protein malnutrition could be completely reversed for abdominal wall wounds and partially reversed for colonic anastomoses in rats on a low-protein diet given postoperative parenteral nutrition (group C). Autoradiographic studies showed a marked decrease in the activity of wound fibroblasts that was restored by the administration of postoperative parenteral nutrition. Serum protein measurements showed a closer correlation of colonic anastomotic healing to serum albumin than to serum transferrin values but showed no correlation with abdominal wall wound healing.

Abdominal Muscles↗

PubMed1981

Emergency abdominal wall reconstruction with polypropylene mesh: short-term benefits versus long-term complications.

The acute replacement of full-thickness abdominal wall has been facilitated by polypropylene mesh (Marlex) (PPM), allowing debridement of nonviable tissue and restoration of abdominal wall integrity without tension. However, no substantial long-term follow-up has been reported on the definitive wound coverage after the use of PPM in open wounds. Since 1976, we have placed PPM in 31 patients; 25 for infectious complication, three for massive bowel distension preventing abdominal closure, and three for shotgun wounds with extensive tissue loss. In 29 of 31 patients, the mesh was placed in heavily contaminated wounds; extensive fasciitis was present in 23 patients and 21 had intra-abdominal abscesses. Following mesh placement, 23 reoperations were required for continuing complications. No patients eviscerated, despite these multiple procedures. Polypropylene mesh was highly effective in restoring abdominal wall continuity. Despite advantages when PPM was used, significant long-term problems developed. Seven patients died from their primary illness in the postoperative period. Nine wounds were closed by granulation and subsequent split-thickness skin grafts. All nine developed mesh extrusion and/or enteric fistulae. Nine wounds healed by secondary intention, six developed enteric fistulae or continuing mesh extrusion. Full-thickness flap coverage after granulation provided the best means of wound closure. Polypropylene mesh had significant early advantages for providing abdominal wall integrity even in the presence of severe infection. However, long-term problems were common when wounds were closed to skin grafts or secondary intention. If the mesh cannot be completely removed, strong consideration should be given to myocutaneous flaps for coverage after the primary illness has resolved.

Abdominal Injuries↗

PubMed2001

[Late abdominal wall leaks of dialysis fluid--own experience in conservative treatment].

The late abdominal wall leaks (LAWL) of dialysis fluid is a serious technical complication of continuous ambulatory peritoneal dialysis (CAPD). Manifestation of LAWL is a significant diagnostic and therapeutic problem. The aim of our study was to establish of diagnostic procedure and the methods of treatment of LAWL. The group of 80 patients treated with CAPD was observed during one-year-period. LAWL appeared in 8 patients from this group. LAWL was diagnosed by: physical examination, abdominal circumference measurement, ultrasound examination of abdominal wall. Patients with LAWL were temporary transferred from CAPD to automated peritoneal dialysis (APD). After applied treatment the remission of leakage was observed. Basing on performed observation we concluded, that physical examination, abdominal circumference measurement and ultrasound examination of abdominal wall are the basal diagnostic methods of LAWL and that temporary change of dialysis method from CAPD to APD is an effective method of LAWL treatment.

Adult↗

PubMed2003

Influence of vascular delay on abdominal wall complications in unipedicled TRAM flap breast reconstruction.

Surgically delaying a unipedicled lower abdominal transverse rectus abdominis musculocutaneous (TRAM) flap has been shown to improve flow within the flap. This delay, however, also affects blood supply and drainage of the entire anterior abdominal wall. The purpose of this study was to compare the abdominal complications between surgically delayed and nondelayed TRAM flaps. A retrospective case review of lower abdominal TRAM flap breast reconstructions was performed. A total of 35 patients were included in the study, of whom 15 had undergone delay and 20 had not. The patients were found to be matched by age and body mass index. There was a higher incidence of smokers (past or present) in the delayed series. Despite this, no abdominal flap complications were experienced in those who underwent delay. In the nondelayed series, however, three patients (15%) experienced delayed healing, and two flaps (10%) underwent severe necrosis (p = 0.047, chi-squared test). In the delayed series, one patient (7%) was found to have an abdominal bulge. No hernias were encountered. In contrast, two bulges (10%) and four hernias (20%) were identified in patients in the nonndelayed series (p = 0.6 and 0.09, respectively, chi-squared test). These data suggest that a preliminary delay procedure leads to a reduction in the incidence of abdominal wall complications in unipedicled lower abdominal TRAM flaps.

Abdominal Wall↗

PubMed1996

Laparoscopic transillumination for the location of anterior abdominal wall blood vessels.

OBJECTIVE: To determine the efficacy of transillumination for locating abdominal wall vessels prior to trocar placement during laparoscopy. DESIGN: Prospective clinical descriptive study. SETTING: Normal human volunteers in an academic research environment. PATIENTS: Forty-seven white and 21 black women of various weights undergoing laparoscopy for clinical indications unrelated to this study. INTERVENTIONS: None. MAIN OUTCOME MEASURES: The location and number of abdominal wall vessels visible by transillumination were recorded for each patient. RESULTS: In women of normal weight, a single vessel could be seen approximately 5 cm from the midline in > 90% of the patients, and second vessel approximately 8 cm from the midline could also be seen in 51%. The more medial vessels did not correlate with the course of the inferior epigastric vessels seen laparoscopically. The ability to see vessels was decreased significantly by the patients' weight but not by skin color. CONCLUSIONS: Superficial abdominal wall vessels may be located by transillumination in the majority of women of normal weight regardless of skin color, but is of less value in overweight and obese women. However, the deep (inferior) epigastric vessels cannot be effectively located by transillumination, and thus other techniques should be used to minimize the risk of injury to these vessels.

Abdominal Muscles↗

PubMed2006

Management of neonates with large abdominal wall defects and undescended testis.

OBJECTIVES: To assess, in a retrospective study, the outcome of different treatment modalities in newborns with undescended testes secondary to large abdominal wall or diaphragmatic defects. Large abdominal and diaphragmatic defects are known to be associated with cryptorchidism, yet the reported incidence varies widely. METHODS: A total of 112 neonates with large abdominal wall or diaphragmatic defects were treated from 1981 to 2005. Of the 55 male patients in this series, 9 (16.4%) presented with abdominal testes and 4 had an extra-abdominal testis (7.3%). RESULTS: The 2 patients undergoing primary orchiopexy had testes of normal size and in the normal position at last follow-up. In one of these patients in whom the testis was brought down to the internal inguinal ring, spontaneous descent occurred and the testis on the affected side was normal. The other patient required additional surgery and had an atrophic testis at last follow-up. In 1 patient with severe concomitant malformations, primary orchiectomy was performed. The 4 patients who did not receive initial treatment all lost their testes owing to atrophy. CONCLUSIONS: The results of the present study have indicated that primary orchiopexy should be attempted in all cases of abdominal wall defects associated with abdominal cryptorchid testes because it yields better testicular salvage rates. In cases in which the spermatic cord is not long enough to place the testis into the scrotum, mobilization and fixation at the lowest site possible resulted in better outcomes than leaving the testis in the abdomen.

Abnormalities, Multiple↗

PubMed1980

Abdominal wall disfigurement.

The four deforming elements of the anterior abdominal wall--obesity, intestinal distension, gravitation, and muscular diastasis (the abdominal wall tetrad)--are described. The first two belong to medicine, and the last two to the surgeon's skill. Four degrees of deformity are described. Specific intervention is indicated for the correction of each of these degrees of deformity. In no case is the operation disabling, nor does it require an exceedingly long recovery time.

Abdominal Muscles↗

PubMed1995

Dissection of the anterior abdominal wall and the deep inguinal region from a laparoscopic perspective.

The usual dissection by medical students of the anterior abdominal wall and the inguinal region proceeds from superficial to deep; special emphasis is placed on the sheath of the rectus abdominis muscle and lateral muscular layers. We suggest an alternate approach to dissection of this region that has the following advantages: (1) sparing of delicate deep structures not often fully appreciated by students; (2) provision of an opportunity to visualize the region from a laparoscopic surgeon's vantage point; (3) considerably reduced time spent dissecting and identifying structures and relationships, especially peritoneal reflections important in laparoscopic procedures. Our dissection begins with bilateral subcostal incisions through the entire thickness of the anterior abdominal wall and peritoneum, which extend laterally and inferiorly to the level of the anterior superior iliac spines, thereby forming a large, inverted, U-shaped flap. This flap is reflected inferiorly, allowing abdominal viscera to be dissected, and ultimately removed en bloc. The flap is then drawn cranially and stretched somewhat to approximate its position when the abdomen is inflated with CO2 during laparoscopic procedures. Major landmarks, including the deep inguinal ring, are noted and the flap is again reflected inferiorly for dissection beginning with the peritoneum and transversalis fascia. This method of dissecting the anterior abdominal wall and inguinal region results in more facile and timely identification of both superficial and deep structures of the anterior abdominal wall and inguinal region, and provides a clinically relevant demonstration of anatomy from a laparoscopic perspective.

Abdominal Muscles↗

PubMed2001

Lactate metabolism during laparoscopic cholecystectomy: comparison between CO2 pneumoperitoneum and abdominal wall retraction.

Recent reports have implicated CO2 pneumoperitoneum for laparoscopic surgery in the occurrence of postoperative mesenteric ischemia. With this kind of surgery, the increase in blood lactate levels has been attributed to anaerobic metabolism, probably due to tissue ischemia induced by high intraabdominal pressure (IAP). The aim of this study was to evaluate the metabolic repercussion of CO2 pneumoperitoneum during laparoscopic cholecystectomy (LC). This was a prospective randomized study of CO2 pneumoperitoneum (PP group, n = 19) versus abdominal wall retraction (AWR group, n = 15). Demographic data were collected preoperatively. Four-trocar LC was performed with either a CO2 pneumoperitoneum (IAP of 12 mmHg) or abdominal wall retraction (abdominal wall pressure 6-10 kp). Intraoperative and postoperative blood samples were collected and lactate levels determined by enzymatic analysis. Repeated measures analysis of variance (MANOVA) was used for statistical analysis. Significance was evaluated at p < 0.05. The groups were shown to be homogeneous. Lactate concentration, expressed as mean (SD), went from 25.4 (14.4) mg/dl at baseline to 18.9 (13.6) mg/dl 4 hours after surgery in the PP group and from 19.4 (6.1) mg/dl at baseline to 17.8 (14.7) mg/dl in the AWR group. No significant differences were found between groups intraoperatively (p = 0.116) or postoperatively (p = 0.99). Our study did not show significant differences in blood lactate levels during LC with CO2 pneumoperitoneum compared to the same procedure with abdominal wall retraction.

Abdominal Muscles↗

PubMed1998

The effect of abdominal wall morphology on ultrasonic pulse distortion. Part I. Measurements.

The relative importance of the fat and muscle layers of the human abdominal wall in producing ultrasonic wavefront distortion was assessed by means of direct measurements. Specimens employed included six whole abdominal wall specimens and twelve partial specimens obtained by dividing each whole specimen into a fat and a muscle layer. In the measurement technique employed, a hemispheric transducer transmitted a 3.75-MHz ultrasonic pulse through a tissue section. The received wavefront was measured by a linear array translated in the elevation direction to synthesize a two-dimensional aperture. Insertion loss was also measured at various locations on each specimen. Differences in arrival time and energy level between the measured waveforms and computed references that account for geometric delay and spreading were calculated. After correction for the effects of geometry, the received waveforms were synthetically focused. The characteristics of the distortion produced by each specimen and the quality of the resulting focus were analyzed and compared. The measurements show that muscle produces greater arrival time distortion than fat while fat produces greater energy level distortion than muscle, but that the distortion produced by the entire abdominal wall is not equivalent to a simple combination of distortion effects produced by the layers. The results also indicate that both fat and muscle layers contribute significantly to the distortion of ultrasonic beams by the abdominal wall. However, the spatial characteristics of the distortion produced by fat and muscle layers differ substantially. Distortion produced by muscle layers, as well as focal images aberrated by muscle layers, show considerable anisotropy associated with muscle fiber orientation. Distortion produced by fat layers shows smaller-scale, granular structure associated with scattering from the septa surrounding individual fat lobules. Thick layers of fat may be expected to cause poor image quality due to both scattering and bulk absorption effects, while thick muscle layers may be expected to cause focus aberration due to large arrival time fluctuations. Correction of aberrated focuses using time-shift compensation shows more complete correction for muscle sections than for fat sections, so that correction methods based on phase screen models may be more appropriate for muscle layers than for fat layers.

Abdominal Muscles↗