An old dream revitalised: preconditioning strategies to protect surgical flaps from critical ischaemia and ischaemia-reperfusion injury

The prevention of ischaemia and the adequate restitution of blood flow to ischaemic tissue are pivotal to halt the progression of cellular injury associated with decreased oxygen and nutrient supply. Accordingly, the search for novel strategies which aim at preventing ischaemia-reperfusion-induced tissue damage is still of major interest in flap surgery. Preconditioning represents an elegant approach to render the tissue more resistant against deleterious ischaemic insults. For many decades, 'surgical delay' has been the standard method of tissue preconditioning. During the last 10 years, ischaemic preconditioning was added to the repertoire of plastic surgeons to protect flaps from ischaemic necrosis. The invasiveness and expenditure of time of these procedures, however, have always been major drawbacks, hindering a wide distribution in clinical practice. Consequently, the motivation has all along been to further refine and simplify protective strategies. Recent experimental studies have now shown that efficient protection from ischaemic necrosis can also be achieved by remote preconditioning or pretreatment with chemical agents and growth factors, which mimic the action of surgical delay and ischaemic preconditioning. In addition, the local application of unspecific stressors, including both heating and cooling, have been shown to effectively improve flap microcirculation and, thus, tissue survival. In view of successful translational research, it is now time that the efficacy of these novel preconditioning procedures is proven in prospective randomised clinical trials.

Prosthetic considerations

Implants have changed prosthodontics more than any other innovation in dentistry. Replacement of lost teeth by a fixed or removable prosthesis is considered to be a restitutio ad similem, while implants may provide a feeling of restitutio ad integrum. Implant prosthodontics means restoring function, aesthetics, and providing technology; biology and technology are combined. Placement of implants is a reconstructive, preprosthetic surgical intervention and is therefore different from most goals in oral surgery that consist of tooth extraction, treating infection and removing pathology from soft or hard tissues. Thus, implants are part of the final prosthetic treatment which encompasses functional, aesthetic and social rehabilitation. The patient's needs and functional status determine the goal of prosthetic treatment. Treatment outcomes in implant prosthodontics are survival of implants and prostheses, impact on physiological and psychological status, oral health-related impact on quality of life, and initial and maintenance costs. A variety of prosthetic solutions are available to restore the partially and completely edentulous jaw and more recently specific methods have been developed such as computer guided planning and CAD-CAM technologies. These should allow more uniform quality and passive fit of prostheses, and simultaneously enables processing of biologically well-accepted materials.

Childhood leukaemia and socioeconomic status: what is the evidence?

The objectives of this systematic review are to summarise the current literature on socioeconomic status (SES) and the risk of childhood leukaemia, to highlight methodological problems and formulate recommendations for future research. Starting from the systematic review of Poole et al. (Socioeconomic status and childhood leukaemia: a review. Int. J. Epidemiol. 2006;35(2):370-384.), an electronic literature search was performed covering August 2002-April 2008. It showed that (1) the results are heterogeneous, with no clear evidence to support a relation between SES and childhood leukaemia; (2) a number of factors, most importantly selection bias, might explain inconsistencies between studies; (3) there is some support for an association between SES at birth (rather than later in childhood) and childhood leukaemia and (4) if there are any associations, these are weak, limited to the most extreme SES groups (the 10-20% most or least deprived). This makes it unlikely that they would act as strong confounders in research addressing associations between other exposures and childhood leukaemia. Future research should minimise case and control selection bias, distinguish between different SES measures and leukaemia subtypes and consider timing of exposures and cancer outcomes.

Testing the GlaaS algorithm for dose measurements on low- and high-energy photon beams using an amorphous silicon portal imager

The GLAaS algorithm for pretreatment intensity modulation radiation therapy absolute dose verification based on the use of amorphous silicon detectors, as described in Nicolini et al. [G. Nicolini, A. Fogliata, E. Vanetti, A. Clivio, and L. Cozzi, Med. Phys. 33, 2839-2851 (2006)], was tested under a variety of experimental conditions to investigate its robustness, the possibility of using it in different clinics and its performance. GLAaS was therefore tested on a low-energy Varian Clinac (6 MV) equipped with an amorphous silicon Portal Vision PV-aS500 with electronic readout IAS2 and on a high-energy Clinac (6 and 15 MV) equipped with a PV-aS1000 and IAS3 electronics. Tests were performed for three calibration conditions: A: adding buildup on the top of the cassette such that SDD-SSD = d(max) and comparing measurements with corresponding doses computed at d(max), B: without adding any buildup on the top of the cassette and considering only the intrinsic water-equivalent thickness of the electronic portal imaging devices device (0.8 cm), and C: without adding any buildup on the top of the cassette but comparing measurements against doses computed at d(max). This procedure is similar to that usually applied when in vivo dosimetry is performed with solid state diodes without sufficient buildup material. Quantitatively, the gamma index (gamma), as described by Low et al. [D. A. Low, W. B. Harms, S. Mutic, and J. A. Purdy, Med. Phys. 25, 656-660 (1998)], was assessed. The gamma index was computed for a distance to agreement (DTA) of 3 mm. The dose difference deltaD was considered as 2%, 3%, and 4%. As a measure of the quality of results, the fraction of field area with gamma larger than 1 (%FA) was scored. Results over a set of 50 test samples (including fields from head and neck, breast, prostate, anal canal, and brain cases) and from the long-term routine usage, demonstrated the robustness and stability of GLAaS. In general, the mean values of %FA remain below 3% for deltaD equal or larger than 3%, while they are slightly larger for deltaD = 2% with %FA in the range from 3% to 8%. Since its introduction in routine practice, 1453 fields have been verified with GLAaS at the authors' institute (6 MV beam). Using a DTA of 3 mm and a deltaD of 4% the authors obtained %FA = 0.9 +/- 1.1 for the entire data set while, stratifying according to the dose calculation algorithm, they observed: %FA = 0.7 +/- 0.9 for fields computed with the analytical anisotropic algorithm and %FA = 2.4 +/- 1.3 for pencil-beam based fields with a statistically significant difference between the two groups. If data are stratified according to field splitting, they observed %FA = 0.8 +/- 1.0 for split fields and 1.0 +/- 1.2 for nonsplit fields without any significant difference.

Body contouring surgery following bariatric surgery and dietetically induced massive weight reduction: a risk analysis

BACKGROUND: This study analyzed the impact of weight reduction method, preoperative, and intraoperative variables on the outcome of reconstructive body contouring surgery following massive weight reduction. METHODS: All patients presenting with a maximal BMI >/=35 kg/m(2) before weight reduction who underwent body contouring surgery of the trunk following massive weight loss (excess body mass index loss (EBMIL) >/= 30%) between January 2002 and June 2007 were retrospectively analyzed. Incomplete records or follow-up led to exclusion. Statistical analysis focused on weight reduction method and pre-, intra-, and postoperative risk factors. The outcome was compared to current literature results. RESULTS: A total of 104 patients were included (87 female and 17 male; mean age 47.9 years). Massive weight reduction was achieved through bariatric surgery in 62 patients (59.6%) and dietetically in 42 patients (40.4%). Dietetically achieved excess body mass index loss (EBMIL) was 94.20% and in this cohort higher than surgically induced reduction EBMIL 80.80% (p < 0.01). Bariatric surgery did not present increased risks for complications for the secondary body contouring procedures. The observed complications (26.9%) were analyzed for risk factors. Total tissue resection weight was a significant risk factor (p < 0.05). Preoperative BMI had an impact on infections (p < 0.05). No impact on the postoperative outcome was detected in EBMIL, maximal BMI, smoking, hemoglobin, blood loss, body contouring technique or operation time. Corrective procedures were performed in 11 patients (10.6%). The results were compared to recent data. CONCLUSION: Bariatric surgery does not increase risks for complications in subsequent body contouring procedures when compared to massive dietetic weight reduction.

Review of 197 consecutive free flap reconstructions in the lower extremity

Complications and failures after microvascular free tissue transfer for lower extremity reconstruction have a negative impact on postoperative course and final outcome. Therefore, a 10-year analysis on lower extremity reconstruction with free flaps was performed with a special emphasis on patient co-morbidities such as cardiovascular diseases, diabetes mellitus, body mass index and history of smoking, in order to identify potential risk factors. Complications such as haematoma, seroma, infection, wound dehiscence, as well as partial flap loss, postoperative thrombosis of the anastomosis and eventual total flap loss were gathered from the medical records. Limb salvage was 100%, however 40% suffered from complications ranging from minor wound dehiscence to total flap loss. None of the above-mentioned potential risk factors was associated with an increased rate of complications. However, in flaps that required revision for thrombosis, the age of the patients was significantly higher in the group of flaps that eventually failed when compared to flaps that were salvaged. In conclusion, lower extremity reconstruction with microvascular free tissue transfer is a safe and reliable procedure with a high success rate, however partial flap loss remains an important issue. Increased age was the only factor identified with an increased risk for subsequent flap loss in cases that were revised for thrombosis.

Secondary breast reconstruction with deepithelialized free flaps from the lower abdomen for intractable capsular contracture and maintenance of breast volume

Although surgical techniques and the quality of mammary prostheses have been improved significantly in recent years, capsular contracture attendant on prosthetic mammary reconstruction remains a major flaw. Although rarely, some patients are confronted with recurrent and intractable capsular contractures with resultant breast deformity, even after multiple attempts at capsulectomies and implant exchange. Patients with recurrent capsular contracture often do not want replacement with a new prosthesis, but desire the maintenance of their breast volume with a safe alternative. In an attempt to maintain breast volume and to improve the aesthetic appearance, secondary breast reconstruction using bilateral deepithelialized free flaps from the lower abdomen was performed in a series of seven patients. Three bilateral muscle-sparing TRAM flaps, two bilateral DIEP flaps, one bilateral SIEA flap, one unilateral SIEA flap, and one unilateral DIEP flap (a total number of 14 flaps) were used following implant removal, total capsulectomy, and prophylactic subcutaneous mastectomy. The early postoperative course was uneventful, and all flaps survived completely with no complications. There were no donor-site problems, except in one patient (case 5), who had partial skin necrosis of the abdominal flap. The long-term results (mean follow-up: 4.8 years) demonstrated an aesthetically satisfactory appearance of the breasts, with no major donor-site problems. Several advantages, as well as drawbacks, are highlighted with this technique.

Practical use of digital cameras for microphotography through the operating microscope

A practical use of personal digital cameras for taking digital photographs in the microsurgical field through an operating microscope is described. This inexpensive and practical method for acquiring microscopic images at the desired magnification combines the advantages of the digital camera and the operating microscope.

(18)F-Immuno-PET: Determination of Anti-CD66 Biodistribution in a Patient with High-Risk Leukemia

The monoclonal antibody anti-CD66 labeled with (99m)Tc is widely used as Scintimun((R)) granulocyte for bone marrow immunoscintigraphy. Further, recently performed clinical radioimmunotherapy studies with [(90)Y]Y-anti-CD66 proved to be suitable for the treatment of hematologic malignancies. Before radioimmunotherapy with [(90)Y]Y-anti-CD66, dosimetric estimations are required to minimize radiotoxicity and determine individual applicable activities. Planar imaging, using gamma-emitting radionuclides, is conventionally carried out to estimate the absorbed organ doses. In contrast, immuno-PET (positron emission tomography) enables the quantification of anti-CD66 accumulation and provides better spatial and temporal resolution. Therefore, in this study, a semiautomated radiosynthesis of [(18)F] F-anti-CD66 was developed, using the (18)F-acylation agent, N-succinimidyl-4-[(18)F]fluorobenzoate ([(18)F]SFB). As a proof of concept, an intraindividual comparison between PET and conventional scintigraphy, using (18)F- and (99m)Tc-labeled anti-CD66 in 1 patient with high-risk leukemia, is presented. Both labeled antibodies displayed a similar distribution pattern with high preferential uptake in bone marrow. Urinary excretion of [(18)F] F-anti-CD66 was increased and bone marrow uptake reduced, in comparison to [(99m)Tc]Tc-anti-CD66. Nevertheless, PET-based dosimetry with [(18)F] F-anti-CD66 could provide additional information to support conventional scintigraphy. Moreover, [(18)F]F-anti-CD66 is ideally suited for bone marrow imaging using PET.

Femoral morphology due to impingement influences the range of motion in slipped capital femoral epiphysis

Femoroacetabular impingement due to metaphyseal prominence is associated with the slippage in patients with slipped capital femoral epiphysis (SCFE), but it is unclear whether the changes in femoral metaphysis morphology are associated with range of motion (ROM) changes or type of impingement. We asked whether the femoral head-neck junction morphology influences ROM analysis and type of impingement in addition to the slip angle and the acetabular version. We analyzed in 31 patients with SCFE the relationship between the proximal femoral morphology and limitation in ROM due to impingement based on simulated ROM of preoperative CT data. The ROM was analyzed in relation to degree of slippage, femoral metaphysis morphology, acetabular version, and pathomechanical terms of "impaction" and "inclusion." The ROM in the affected hips was comparable to that in the unaffected hips for mild slippage and decreased for slippage of more than 30 degrees. The limitation correlated with changes in the metaphysic morphology and changed acetabular version. Decreased head-neck offset in hips with slip angles between 30 degrees and 50 degrees had restricted ROM to nearly the same degree as in severe SCFE. Therefore, in addition to the slip angle, the femoral metaphysis morphology should be used as criteria for reconstructive surgery.