Anders G. Liss

Preoperative CT angiography reduces surgery time in perforator flap reconstruction

UNLABELLEDnThe use of perforator flaps in breast reconstructions has increased considerably in the past decade. A disadvantage of the perforator flap is difficult dissection, which results in a longer procedure. During spring 2006, we introduced CT angiography (CTA) as part of the diagnostic work-up in perforator flap reconstructions to visualise each perforator more accurately. The main objectives were to reduce surgery time and the number of complications. A chart review was conducted 1 year after CTA introduction to investigate if these objectives were met.nnnMATERIALS AND METHODSnPatients with a deep inferior epigastric perforator (DIEP) flap who underwent preoperative analysis through CTA were retrospectively evaluated. The population <or=1 year before CTA introduction were the control group. The two groups were compared with respect to surgery time and complications (including flap failure).nnnRESULTSnOne hundred and thirty-eight DIEP breast reconstructions were done; 70 underwent preoperative CTA analysis, and 68 had preoperative Doppler investigation. Surgery time in the CTA group was significantly lower (P<0.001) than in the control group, 264 min (SD+/-62) versus 354 min (SD+/-83), respectively. There was a tendency for fewer complications in the CTA group compared with the control group. All flaps were successful in the CTA group. In the control group, one flap failed and partial necrosis occurred in three flaps. The differences were not statistically significant.nnnCONCLUSIONSnPreoperative CTA in the assessment of vascular anatomy during perforator flap reconstruction was safe and reliable. It helped reduce surgery time, and may prevent the number of postoperative complications.

Post operative monitoring of microvascular breast reconstructions using the implantable Cook-Swartz doppler system: a study of 145 probes & technical discussion.

INTRODUCTIONnAccurate post operative assessment of free tissue transfers is challenging despite all the subjective and objective techniques available today. In our continual search to optimise patient outcomes, we introduced the Cook-Swartz probe into our clinical practice in May 2006.nnnMETHODSnWe present our single centre experience in 103 patients undergoing 121 microvascular breast reconstructions and monitored using implantable Cook-Swartz venous dopplers between May 2006 and January 2008.nnnRESULTSnIn total, we used 145 probes on 121 microvascular breast reconstructions (DIEP=102, SIEP=15, SGAP=4) in 103 female patients. The mean operative time was 4h and 55 min (mu=295; range 117-630; ó+/-101 min) and we suffered 2 complete flap losses. A problem with the audible signal was noted in 15 patients (4 intra-operatively). We revised 14 of the 15. All fourteen had compromised anastomoses. In the remaining case, the patient was not returned to theatre as the primary surgeon was confident there were no other signs of vascular compromise. Overall, when using the venous doppler probe we found a false positive rate of 6.7% and 0% false negatives.nnnDISCUSSIONnWe advocate the use of a Cook-Swartz probe which has been well received by both surgeons, nursing staff and patients, as an adjunct to traditional clinical monitoring techniques. We also include a comprehensive experience based technical discussion concerning its application, attachment, use and post-operative removal.

Introduction of the Implantable Doppler System Did Not Lead to an Increased Salvage Rate of Compromised Flaps: A Multivariate Analysis

Background: The Cook-Swartz implantable Doppler system was introduced at the Uppsala University Hospital to ease free flap monitoring and improve salvage rates by an earlier detection of vascular compromise. The aim of the current analysis was to investigate whether the system indeed improved the salvage rate of revisions. Methods: All cases that needed revision among a consecutive series of patients being monitored with the implantable Doppler system between June of 2006 and January of 2009 were compared with a similar set of patients operated on before the introduction of the implantable Doppler system over an equal time span monitored with conventional methods. Data were extracted from the medical files of the patients. Logistic regression was used to identify factors associated with the outcome of the revision. Values of p < 0.05 were considered statistically significant. Results: A total of 327 flaps were monitored with the implantable Doppler system, of which 35 needed revision. In the control group, 303 flaps were included, of which 40 needed revision. The revision was successful in 69 percent of the cases in the implantable Doppler system group; in the group monitored by only conventional methods, this rate was 60 percent. Univariate analysis showed no statistical difference between these success rates (p = 0.441; odds ratio, 1.455; 95 percent confidence interval, 0.560 to 3.775). Multivariate analysis did not show a statistical difference either (p = 0.799; odds ratio, 1.143; 95 percent confidence interval, 0.410 to 3.182). Conclusion: The introduction of the implantable Doppler system did not lead to a significant increase in the salvage rate of revised flaps.

Aesthetic refinements and reoperative procedures following 370 consecutive DIEP and SIEA flap breast reconstructions: important considerations for patient consent.

BackgroundBreast reconstruction often requires multiple operations. In addition to potential complications requiring reoperation, additional procedures are frequently essential in order to complete the reconstructive process, with aesthetic outcome and breast symmetry shown to be the most important factors in patient satisfaction. Despite the importance of these reoperations in decision-making and the consent process, a thorough review of the need for such operations has not been definitively explored.MethodsA review of 370 consecutive autologous breast reconstructions (326 patients) was undertaken, comprising 365 deep inferior epigastric artery perforator (DIEP) flaps and 5 superficial inferior epigastric artery (SIEA) flaps. The need for additional procedures for either complications or aesthetic refinement following initial breast reconstruction was assessed.ResultsOverall, there was an average of 1.06 additional interventions for every patient carried out after primary reconstructive surgery. Of 326 patients, 46 underwent early postoperative operations for surgical complications (0.17 additional operations per patient as a consequence of complications). Procedures for aesthetic refinement included those performed on the reconstructed breast, contralateral breast, or abdominal donor site. Procedures for aesthetic refinement included nipple reconstruction, nipple–areola complex tattooing, dog-ear correction, liposuction, lipofilling, scar revision, mastopexy, and reduction mammaplasty.ConclusionWhile DIEP flap surgery for breast reconstruction provides favorable results, patients frequently require additional procedures to improve aesthetic outcomes. The need for reoperation is an important part of the consent process prior to reconstructive surgery, and patients should recognize the likelihood of at least one additional procedure following initial reconstruction.

Cell Loss in Sensory Ganglia After Peripheral Nerve Injury: An Anatomical Tracer Study Using Lectin-Coupled Horseradish Peroxidase in Cats

In 33 adult cats the lateral superficial branch of the radial nerve was exposed and transsected on one side. In one group of animals (n = 22) the nerve-stumps were re-approximated with epineural sutures and in the other group (n = 11) the proximal nerve stump was enclosed to prevent regeneration. After survival periods ranging from 4-17 months the same nerve on both sides was exposed to an intra-axonal nerve tracer to label the dorsal root ganglion neurones projecting into the nerve being investigated. In each animal the opposite side was used as control. When the transsection was followed by a nerve suture the mean proportion of labelled sensory neurones in the dorsal root ganglion, compared with the control side, was 61% at eight months after operation, but by 17 months it had increased to 70%. When regeneration was prevented by the proximal nerve stump being enclosed in a plastic envelope, the reduction in labelled cells was 45% after a survival period of 17 months.

A Clinical Review of 9 Years of Free Perforator Flap Breast Reconstructions: An Analysis of 675 Flaps and the Influence of New Techniques on Clinical Practice

The aim of this study is to review our 9-year experience with deep inferior epigastric perforator (DIEP) breast reconstructions to help others more easily overcome the pitfalls we experienced. A chart review was conducted for all 543 patients who had 622 DIEP breast reconstructions in our clinic between January 2000 and January 2009. In this time, there were an additional 28 superior gluteal artery perforator and 25 superficial inferior epigastric artery reconstructions, bringing the total free flap reconstructions to 675. In the early years, the success rate was 90.7%, the average operative time was 7 hours and 18 minutes, and the complication rate was 33.3%; these have improved to 98.2%, 4 hours and 8 minutes, and 19.3%, respectively. We describe our selection criteria, preoperative vascular mapping, surgical techniques, and postoperative monitoring as they relate to these improvements in outcome, operative time, and complications. The DIEP flap is a safe and reliable option in breast reconstructions. By acquiring experience with the flap and introducing new and improving existing techniques we have improved the ease of the procedure and the success rate and have shortened the operative time.

Primary sensory neuron survival following targeted administration of nerve growth factor to an injured nerve

Nerve injuries induce neurochemical changes within primary sensory neurons, including expression of neuropeptides, and a loss of a substantial proportion of the neurons may possibly be caused by a lack of neurotrophic support. In the present study the role of nerve growth factor (NGF) in preventing these changes was investigated in monkeys by giving NGF peripherally through a fibronectin (Fn) conduit. A sensory nerve (superficial radial) was transected and a gap of 5 mm was bridged with either autologous sural nerve graft (SNG), Fn, or Fn impregnated with NGF (Fn-NGF). After four months the dorsal root ganglia, that received the cutaneous afferents of the nerve, were removed and analysed by quantitative immunohistochemistry using antibodies to calcitonin gene related polypeptide (CGRP) and substance P. The percentage of immunostained cells was taken as an indication of neuronal survival. The results showed that SNG and Fn-NGF reduced the loss of CGRP positive sensory neurons compared with Fn alone. For substance P-positive neurons the differences were small with only a tendency towards reduction of neuronal death after NGF had been given, suggesting that NGF might act preferentially on a subpopulation of CGRP immunoreactive sensory neurons that do not coexist with substance P.

Changes in the Spinal Terminal Pattern of the Superficial Radial Nerve After A Peripheral Nerve Injury: An Anatomical Study in Cats

The occurrence of changes within the spinal cord over a long period after a peripheral nerve injury was investigated in adult cats. The lateral superficial branch of the radial nerve was exposed and transsected unilaterally. In one group the nerve endings were re-approximated with epineural sutures and in the other group the proximal nerve stump was enclosed to prevent regeneration. After a survival period of 4-17 months the same nerve on both sides was exposed to an intra-axonal nerve tracer, lectin-conjugated horseradish peroxidase, to label the nerve terminals within the spinal gray matter by transganglionic transport. The general distribution of the terminal field was almost the same after suturing as after encapsulation of the transsected nerve, except for a slightly more cranial location of the terminal area after suturing compared with the control side. The terminal area comprised laminae I-IV of the fifth cervical to the first thoracic spinal segment, concentrated towards the sixth to eighth cervical segments. This distribution was the same as on the control side, but the experimental and control sides differed in intensity of terminals. There was a loss of terminals throughout the terminal field in both operated groups, but after nerve suture there was some recovery of terminal intensity between 4 and 17 months after the injury.

Measuring the Pressure in the Superficial Inferior Epigastric Vein to Monitor for Venous Congestion in Deep Inferior Epigastric Artery Perforator Breast Reconstructions: A Pilot Study

During deep inferior epigastric artery perforator (DIEP) flap dissection, we noted that in many cases the superficial vein on the ipsilateral side of the flap was engorged and tense, and in others, it was empty. This led us to believe that the pressure is increased as the result of preferential outflow through the superficial vein in some cases, which could result in venous congestion of the flap if this vessel was not anastomosed. To test this hypothesis, we measured the venous pressure in the superficial venous system before and after flap dissection. The pressure in the superficial inferior epigastic vein of a DIEP flap was measured in 26 consecutive flaps to investigate the correlation between the pressure and venous congestion of the flap. The first measurement was performed at the beginning of the dissection, and the second measurement was taken after the flap had been completely raised on a single perforator. The mean increase in pressure after flap dissection was 10.6 mm Hg (mu = 10.6; range -1 to 31; O +/- 7.0 mm Hg). Clinical signs of venous congestion were observed in one case. In this case, the increase in venous pressure was with 31 mm Hg, also the highest. Although the results of this report are preliminary, they indicate that the pressure in the superficial vein of DIEP flaps might be of predictive value for venous congestion.

Reorganisation of Primary Afferent Nerve Terminals in the Brainstem After Peripheral Nerve Injury: An anatomical study in cats

A pure sensory nerve (the superficial branch of the radial nerve) in adult cats was cut to investigate the changes in the nerve endings (terminals) on the neurons of the nucleus cuneatus of the brainstem. In one group of cats (n = 22) the ends of the cut nerve were approximated immediately by epineural suturing to promote optimum regeneration. In another group (n = 11) the proximals tump of the nerve was enclosed in a capsule to prevent regeneration. Four to 17 months later the same nerve was re-exposed. The sutured nerves were cut and nerve-tracer was exhibited to the proximal end of the cut nerves and to the proximal stump of the nerves which had been encapsulated. The purpose was to investigate the labelling of nerve terminals in the cuneate nucleus, because it receives an input of primary afferents from the front leg. The nerve and the cuneate nucleus of the opposite side served as controls. Labelled terminals were distributed throughout the dorsal part of the entire rostrocaudal extent of the cuneate nucleus. The distribution was patchy and was superimposed on clusters of nerve cells. The quantity of labelled nerve terminals on the experimental and control sides was compared: 60% of the labelling observed on the control side was in the sutured nerves while the encapsulated nerves exhibited only 32%. This difference was apparent 4 months after transection of the nerve. Up to 17 months after the nerve was cut, however, there was some increase in the quantity of labelled nerve terminals and this was most apparent in cats in which the nerves had been sutured.