Color Doppler ultrasound versus CT angiography for DIEP flap planning: A randomized controlled trial.

BACKGROUND: Identifying relevant perforators is crucial in planning a deep inferior epigastric perforator (DIEP) flap. Color Doppler ultrasonography (CDU) has gained popularity for localizing perforators; however, current evidence on its efficiency is still inconclusive. This study aimed to compare the efficiency of CDU with that of computed tomography angiography (CTA) in localizing and selecting the relevant perforators. METHODS: In this randomized controlled trial, 60 patients undergoing DIEP flap breast reconstruction (uni- or bilateral) were randomly assigned to the CDU group (i.e., CDU was performed to map and select the relevant perforators preoperatively) or the CTA+CDU group (i.e., mapping was based on CTA and supplemented by CDU). CDU was performed by the same surgeon with a well-defined sonography experience from our previous study. The reference XY coordinates of the dissected perforators were measured intraoperatively, and deviations from preoperatively deducted coordinates were calculated (ΔCDU or ΔCTA+CDU). The flaps were categorized according to the number of dissected perforators, and adherence to the preoperative strategy was evaluated. RESULTS: Overall, 22 patients (30 flaps) in the CTA+CDU group and 27 (39 flaps) patients in the CDU group were evaluated. The average ΔCDU (0.6 cm) was significantly lower than the average ΔCTA+CDU (1.0 cm) (p < 0.001). Adherence to the mapping-based dissection strategy was higher in the CDU group; however, the difference was insignificant (p = 0.092). CONCLUSION: CDU is not inferior to CTA + CDU in localizing and selecting relevant DIEA perforators. Therefore, CDU mapping is a possible complementary or substitute modality for CTA mapping.

Surgeon-conducted color Doppler ultrasound deep inferior epigastric artery perforator mapping: A cohort study and learning curve assessment.

BACKGROUND: Perforator mapping using diagnostic methods facilitates deep inferior epigastric perforator (DIEP) flap planning. Computed tomographic angiography (CTA) is a well-proven tool for perforator mapping. However, the benefits of color Doppler ultrasonography (CDU) are as follows: 1) CDU involves dynamic real-time examination and 2) does not use radiation. Comparing the accuracies of both methods in a cohort of patients, this study aimed to evaluate the learning curve of surgeon-conducted CDU perforator mapping. METHODS: Twenty patients undergoing DIEP flap breast reconstruction were enrolled in a cohort study. All patients underwent CTA perforator mapping preoperatively. XY coordinates of significant perforators were subtracted by a radiologist. A single surgeon (sonographer) with minimal experience with CDU performed CDU perforator mapping, including XY coordinates subtraction. The sonographer was blinded to the CTA data. The reference coordinates of dissected perforators were measured during surgery. Deviations from reference coordinates for both methods were compared, and CDU mapping learning curve was assessed using Joinpoint Regression. RESULTS: We included 20 women (32 DIEP flaps and 59 dissected perforators). The mean deviation between mapped and reference coordinates was 1.00 (0.50-1.12) cm for CDU and 0.71 (0.50-1.12) cm for CTA. The learning curve of CDU mapping showed the breaking point after the seventh patient (≈ 21 localized perforators). After the breaking point, no significant differences between the deviations of both methods were found (p = 0.980). CONCLUSION: A limited number of examinations were needed for the surgeon to learn CDU DIEA perforator mapping with accuracy similar to that of CTA mapping.

Vasospasm of the flap pedicle: the effect of 11 of the most often used vasodilating drugs. Comparative study in a rat model.

BACKGROUND: There has been no review study published yet comparing the effects of the vasodilating drugs that are most often used in clinical practice empirically. The aim of the authors' study was to perform this comparison and to select the drugs that are able to release vasospasm and the drugs that reduce vasospasm duration most effectively in an experimental model in vivo. METHODS: Pedicled groin flaps were dissected in 300 male Wistar rats. Vasospasm was induced by tension applied on the pedicle in the axial direction using a 15-g weight. The blood perfusion of the flap was monitored using a laser Doppler device. The duration of vasospasm was defined as the time from the release of tension until blood flow began to rise. These times were detected using automated computerized detection. The effects of 11 different drugs were studied in 14 groups. The drugs were applied locally; some of them were tested in different concentrations or applied parenterally. RESULTS: Ten percent magnesium sulfate reduced the duration of vasospasm most effectively (p < 0.01). Verapamil applied locally and also pentoxifylline applied parenterally were also very effective. In contrast, the duration of vasospasm was extended after local application of 2% lidocaine (p < 0.01). CONCLUSIONS: The authors concluded that 10% magnesium sulfate applied locally has the best ability to relieve surgically induced vasospasm because of the highest level of significance and reliability. The finding that local application of 2% lidocaine prolongs vasospasm may be surprising.

Role of inflammation and cytokines in peripheral nerve regeneration.

This chapter provides a review of immune reactions involved in classic as well as alternative methods of peripheral nerve regeneration, and mainly with a view to understanding their beneficial effects. Axonal degeneration distal to nerve damage triggers a cascade of inflammatory events alongside injured nerve fibers known as Wallerian degeneration (WD). The early inflammatory reactions of WD comprise the complement system, arachidonic acid metabolites, and inflammatory mediators that are related to myelin fragmentation and activation of Schwann cells. Fine-tuned upregulation of the cytokine/chemokine network by Schwann cells activates resident and hematogenous macrophages to complete the clearance of axonal and myelin debris and stimulate regrowth of axonal sprouts. In addition to local effects, immune reactions of neuronal bodies and glial cells are also implicated in the survival and conditioning of neurons to regenerate severed nerves. Understanding of the cellular and molecular interactions between the immune system and peripheral nerve injury opens new possibilities for targeting inflammatory mediators to improve functional reinnervation.

The effect of smoking on post-operative finger range of motion in patients with tendon grafts.

BACKGROUND: The finger range of motion (ROM) was evaluated in patients with hand flexor tendon replacement using a tendon graft and the effect of smoking was investigated. The first hypothesis was: a tendon graft increases the post-operative ROM. The second hypothesis was: smoking has a negative effect on the final finger ROM. PATIENTS AND METHODS: Fifty seven autologous tendon grafts in 48 patients were included. The patients were grouped as non-smokers or smokers ("light" or "heavy"). The modified Strickland system and Total Active Motion (TAM) system, were chosen for the evaluation. RESULTS: The first hypothesis was proved by all the measurements. The post-operative status assessed by the Strickland method was different between the non-smokers and smokers with a better score in the smokers. CONCLUSION: A significant ROM improvement occurs after reconstruction and is even slightly better in smokers than in non-smokers.