William Y. Hoffman

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

ObjectiveTo analyze a series of patients treated for recurrent or chronic abdominal wall hernias and determine a treatment protocol for defect reconstruction. Summary Background DataComplex 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. MethodsPatients 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. ResultsA 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. ConclusionsFor 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.

Memory regulatory T cells reside in human skin.

Regulatory T cells (Tregs), which are characterized by expression of the transcription factor Foxp3, are a dynamic and heterogeneous population of cells that control immune responses and prevent autoimmunity. We recently identified a subset of Tregs in murine skin with properties typical of memory cells and defined this population as memory Tregs (mTregs). Due to the importance of these cells in regulating tissue inflammation in mice, we analyzed this cell population in humans and found that almost all Tregs in normal skin had an activated memory phenotype. Compared with mTregs in peripheral blood, cutaneous mTregs had unique cell surface marker expression and cytokine production. In normal human skin, mTregs preferentially localized to hair follicles and were more abundant in skin with high hair density. Sequence comparison of TCRs from conventional memory T helper cells and mTregs isolated from skin revealed little homology between the two cell populations, suggesting that they recognize different antigens. Under steady-state conditions, mTregs were nonmigratory and relatively unresponsive; however, in inflamed skin from psoriasis patients, mTregs expanded, were highly proliferative, and produced low levels of IL-17. Taken together, these results identify a subset of Tregs that stably resides in human skin and suggest that these cells are qualitatively defective in inflammatory skin disease.

Giant congenital melanocytic nevi: the significance of neurocutaneous melanosis in neurologically asymptomatic children.

Patients with a giant congenital melanocytic nevus can develop melanotic tumors characterized by central nervous system involvement, termed leptomeningeal melanocytosis or neurocutaneous melanosis. Although symptomatic neurocutaneous melanosis is rare, we previously reported distinct magnetic resonance (MR) findings of T1 shortening, strongly suggestive of neurocutaneous melanosis, in 30 percent (6 of 20) of children with giant congenital melanocytic nevi who presented initially without neurological symptoms. The purpose of this study was to determine the incidence of neurocutaneous melanosis in high‐risk patients and its long‐term clinical significance. Magnetic resonance imaging was recommended for all 46 patients with “at‐risk” giant congenital melanocytic nevi involving the skin overlying the dorsal spine or scalp. The clinical histories and follow‐up of these patients were evaluated by retrospective chart review. Forty‐two underwent MR imaging of the brain and 11 underwent additional MR scanning of the spinal cord. Abnormalities were identified in 14 of 43 MR studies, and 23 percent (n = 10) had T1 shortening indicative of melanotic rests within the brain or meninges. None had associated masses or leptomeningeal thickening. The most common areas of involvement in these 10 included the amygdala (n = 8), cerebellum (n = 5), and pons (n = 3). In the group of 11 patients with spinal MR scans, a tethered spinal cord was demonstrated in one. Additional abnormalities were detected by MR scanning, including a middle cranial fossa arachnoid cyst, a Chiari type I malformation, and a crescentic enhancement that subsequently resolved. Clinical follow‐up averaging 5 years (range, 2 to 8 years) revealed that only one of the 46 patients evaluated developed neurological symptoms, manifested as developmental delay, hypotonia, and questionable seizures but no other signs of neurocutaneous melanosis. No patient has developed a cutaneous or central nervous system melanoma. Magnetic resonance findings of neurocutaneous melanosis are relatively common, even in asymptomatic children with giant congenital melanocytic nevi. Although these findings suggest an increased lifetime risk of central nervous system melanoma, they do not signify the eventual development of symptomatic neurocutaneous melanosis during childhood. (Plast. Reconstr. Surg. 107: 933, 2001.)

Volumetric Assessment of Secondary Alveolar Bone Grafting Using Cone Beam Computed Tomography

Objective: To assess the radiographic outcome of secondary alveolar bone grafting in individuals with nonsyndromic unilateral or bilateral cleft lip and palate using cone beam computed tomography. Methods: This prospective study was conducted at the University of California at San Francisco Center for Craniofacial Anomalies on 21 consecutive nonsyndromic complete cleft lip and palate individuals between 8 and 12 years of age who required alveolar bone grafting. Seventeen unilateral and four bilateral cleft lip and palate individuals had preoperative and postoperative cone beam computed tomography scans that were analyzed using Amira 3.1.1 software. Results: The average volume of the preoperative alveolar cleft defect in unilateral cleft lip and palate was 0.61 cm3, and the combined average volume of the right and left alveolar cleft defects in bilateral cleft lip and palate was 0.82 cm3. The average percentage bone fill in both unilateral cleft lip and palate and bilateral cleft lip and palate was 84%. The outcome of alveolar bone grafting was assessed in relation to (1) type of cleft, (2) size of preoperative cleft defect, (3) presence or absence of lateral incisor, (4) root development stage of the maxillary canine on the cleft side, (5) timing, and (6) surgeon. None of these parameters significantly influenced the radiographic outcome of alveolar bone grafting. Conclusions: Secondary alveolar bone grafting of the cleft defect in our center was successful, based on radiographic outcome using cone beam computed tomography scans. Volume rendering using cone beam computed tomography and Amira software is a reproducible and practical method to assess the preoperative alveolar cleft volume and the adequacy of bone fill postoperatively.

Ischial pressure sore coverage: a rationale for flap selection

The role of wound debridement and flap coverage in treating pressure sores is clearly established. However, criteria and supportive clinical data for specific flap selection and the sequence of flaps for coverage of the ischium remain ill-defined. From 1979-1995, 114 consecutive patients underwent flap coverage of 139 ischial pressure sores. Preoperative risk factors, prior flap history, defect size, flap success, complication rates, and the length of hospitalization were retrospectively evaluated and compared for 112 flaps in 87 patients. Flap success was defined as a completely healed wound. Average follow-up was 10 months (range: 1 month-9 years). Overall, 83% (93/112) of the flaps healed. In the majority of cases (75%, 84/112), wound debridement and flap reconstruction was achieved in a single stage. However, there were significant differences in the healing rates among the various flaps used. The inferior gluteus maximus island flap and the inferior gluteal thigh flap had the highest success rates, 94% (32/34) and 93% (25/27), respectively, while the V-Y hamstring flap and the tensor fascia lata flap had the poorest healing rates, 58% (7/12) and 50% (6/12), respectively. Flap success was not significantly affected by the age of the patient or the prior number of flaps used and preoperative risk factors were equally distributed across all types of flaps. The overall complication rate was 37% (41/112), most commonly from a slight wound edge dehiscence (n = 16) that healed with local wound care within one month postoperatively. Results of this study show that proper flap selection and the appropriate sequence of flap use significantly improve success rates for ischial pressure sore coverage in both the short- and long-term. Based upon flap reliability (successful healing rates), reusability, and the need to preserve as many future flap options as possible, a rationale for flap selection is presented which can be individualized to any patient.

Human prolactin and thyrotropin concentrations in the serums of normal and hypopituitary children before and after the administration of synthetic thyrotropin-releasing hormone

Synthetic thyrotropin-releasing hormone (TRH) was administered to normal children and hypopituitary patients in a dose of 7 mug/kg i.v. over 30-60 sec. Serum thyrotropin (TSH) and prolactin (HPr) concentrations were measured by radioimmunoassay before and at 15-min intervals for 2 hr after TRH. In 20 normal children HPr rose from a mean baseline value of 7.0+/-1.2 (SEM) ng/ml to a mean peak value of 39.5+/-5 ng/ml. In 11 patients with growth hormone (GH) deficiency without TSH deficiency. HPr values rose from a mean baseline of 3.6+/-0.8 ng/ml to a mean peak value of 13.9+/-2.8, a significantly less peak response as compared with normal children (P < 0.005). The TSH responses to TRH, however, were statistically indistinguishable from those of normal children. In 10 patients with GH and TSH deficiency both the mean baseline HPr levels (25.0+/-5 ng/ml) and the mean peak HPr levels after TRH (68.5+/-10 ng/ml) were significantly higher (P < 0.005 and < 0.025) than those of normal children. Similar comparisons were also true for the peak TSH responses (P < 0.05). Two panhypopituitary patients released no TSH and only small amounts of HPr after TRH. After thyroid replacement therapy in eight of the patients with GH and TSH deficiency, the mean HPr baseline levels (7.6+/-1.0 ng/ml) and peak levels (23.3+/-4.6 ng/ml) after the same dose of TRH were significantly less than their pretreatment levels (P < 0.001 and < 0.01) and were within the range for normal children. Synthetic TRH stimulates the simultaneous release of TSH and HPr in normal children and most hypopituitary patients. When the concentrations of thyroxine (T4) and triiodothyronine (T3) are low, the levels of HPr before and after TRH are elevated. After thyroid replacement therapy, HPr levels decrease to normal. T4 and/or T3 may condition the production or effects of prolactin-inhibiting factor (PIF) activity. The TSH and HPr responses after TRH in hypopituitary patients will determine whether the primary defect resides in the pituitary or hypothalamus, but cannot delineate the hypothalamic defect as a deficiency of hypothalamic hormone production or neurohumoral transmission.

Influence of radiotherapy on microvascular reconstruction in the head and neck region

Over a 5-year period at the University of California San Francisco, 42 patients who required microvascular reconstruction for abnormalities in the head and neck area were identified. Twenty-four patients (Group I) underwent reconstruction for a variety of neoplastic and non-neoplastic conditions and did not receive radiotherapy. Eighteen patients (Group II) had undergone previous radiotherapy averaging 6,090 rads. The mean ages for Group I and II patients were 40.7 and 55.5 years, respectively. In Group I, 13 muscle, 7 fasciocutaneous, 4 osteocutaneous, and 2 jejunal transfers were performed. In Group II, 11 muscle, 5 fasciocutaneous, 3 osteocutaneous, and 2 jejunal transfers were performed. Flap survival at 3 months was 88% in Group I and 95% in Group II. Wound complication rates were similar in both groups (15% Group I, 19% Group II), as was donor site morbidity (15% Group I, 29% Group II). Operative times (10.9 hours Group I, 10.6 hours Group II) and median postoperative hospitalization (14 days Group I, 16 days Group II) were comparable as well. Four of the five patients in whom the flap procedures failed were subsequently treated by a second microvascular reconstruction. Previous irradiation of the recipient bed did not appear to affect the success of subsequent microvascular reconstruction or the difficulty of such reconstruction as judged by operative time.

Implantable Venous Doppler Monitoring in Head and Neck Free Flap Reconstruction Increases the Salvage Rate

BACKGROUND Free flap success depends on rapid identification and subsequent salvage of failing flaps. Conventional free flap monitoring techniques require an external component, whereas an implantable monitor readily indicates changes in free flap perfusion, especially in buried flaps used in head and neck reconstruction. METHODS This is a retrospective review of 169 consecutive head and neck free flaps reconstructed mostly for oncologic surgical defects in 155 patients from April of 2000 to December of 2006, all of which were monitored by an implantable venous Doppler device. RESULTS There were 25 buried flaps, representing 14.8 percent of 169 flaps. Flap ischemia caused by thrombosis (n = 16), hematoma (n = 2), or tight closure (n = 1) occurred in 11.2 percent of the cases. The Doppler probe detected all of the failing free flaps, and we were able to salvage 18 of 19 ischemic flaps (94.7 percent). All Doppler-detected ischemic nonburied flaps (100 percent) and three of the four buried free flaps were salvaged (75 percent). There were 33 total complications (19.5 percent), with thrombosis occurring in 9.5 percent of the flaps, whereas 12 flaps required reoperation for vascular revision (7.1 percent). The mortality rate was less than 1 percent (0.6 percent). The overall success rate using the implantable Doppler probe was 98.2 percent, which was similar to that of the most recent reported cases of all free flaps in the literature, with significant improvement in the salvage rate for both buried and nonburied head and neck free flaps. CONCLUSION The implantable Doppler probe is a useful monitoring device in buried free flaps and should be considered for use in head and neck reconstruction.

A Prospective Study Of Early Soft Tissue Coverage Of Grade Iiib Tibial Fractures

Between 1987 and 1990, 45 consecutive patients with grade III tibial injuries were treated by an established protocol. There were 31 men and 14 women. The average age was 27 years (range, 17-68 years). The average follow-up was 16 months (range, 12-46 months). Early bony fixation consisted of an external fixator in 28 patients and a non-reamed intramedullary nail in 17 patients. No significant difference in complications was noted between the two types of fixation systems. Forty-three percent of the patients underwent early bone grafting. Free muscle flaps were employed in 78% of patients with a 97% success rate. Local muscle flaps were utilized in 22% of patients with an 84% success rate. Local infection occurred in three patients (6%). Osteomyelitis occurred in two patients (4%). Bony union was present in 98% of patients (44 of 45). Limb salvage was 98% (44 of 45). Early bone grafting (< or = 3 months) yielded earlier bony union (average, 40 weeks) than late bone grafting (average, 52 weeks). This study proves the efficacy of an established protocol of early muscle flap coverage in the management of grade IIIB tibial fractures in a consecutive series of patients. Early bone grafting appears to be beneficial to early bony union. The intramedullary rod fixation system offers an acceptable alternative to the external fixator system in severe acute open tibial fractures.

Three-Dimensional Assessment of the Eruption Path of the Canine in Individuals With Bone-Grafted Alveolar Clefts Using Cone Beam Computed Tomography

Objective To evaluate the eruption path of the permanent maxillary canine during a 1-year period after secondary alveolar bone grafting and to (1) compare the canine eruption path on the cleft and noncleft side, (2) examine the number of congenially missing lateral incisors and the rate of canine impaction, and (3) examine the relationship between the eruption status of the canine and timing of alveolar bone grafting relative to age and canine root development using cone beam computed tomography (CBCT). Methods Cone beam computed tomography scans for 17 nonsyndromic unilateral cleft lip and palate (UCLP), and four bilateral cleft lip and palate (BCLP) consecutive cases of alveolar bone grafting surgery were obtained after orthodontic expansion and before alveolar bone grafting and at least 1 year postsurgery on the Hitachi MercuRay CBCT machine. The DICOM files were imported into Dolphin 3D Imaging 10.5 and reoriented for consistency. The X, Y, and Z coordinates were determined for the canine cusp tip and root tip on both the cleft and noncleft sides. The direction of movement of the canine in 1 year was determined. Results Most canines on both the cleft and noncleft sides moved incisally, facially, and mesially. Twelve percent of the canines on the cleft side appeared to require surgical exposure. Eighty percent of the canines had less than half root development at the time of bone grafting. The amount of root development did not affect the outcome in terms of eruption amount or direction. Conclusions Most canines on both the cleft and noncleft side moved incisally, facially, and mesially.