Level I lymph node involvement in patients with N1b papillary thyroid carcinoma: a prospective study.

Most of the studies on the incidence, pattern, and predictive factors of lymph node (LN) metastasis with papillary thyroid carcinoma (PTC) have been performed retrospectively and no common consensus has been reached regarding the predictors for the involvement of level I LNs. This study was conducted prospectively to determine the incidence and the possible predictors of level I involvement in N1b PTC patients. The study included 30 consecutive patients with N1b stage of PTC. All the patients underwent neck dissection (ND) including level I. The relation between involvement of level I LNs and various clinicopathological variables was studied. Unilateral neck dissection was performed in 24 patients and bilateral neck dissection in six patients leading to 36 NDs. Level I was excised in all patients, with five specimens (14%) positive for metastasis. Levels II, III, IV, V, VI, and VII were positive in 52.8, 58.3, 58.3, 33.3, 63, and 22.2%, respectively. Level I involvement was significantly related to the number of lymph node levels affected (p = 0.003) and macroscopic extranodal invasion (p = 0.04). It was not related to the involvement of other individual levels, gender, age, size of the largest thyroid nodule, size of the largest LN involved, or histo-pathological variant of the tumor. This study suggests that including level I in therapeutic neck dissection for N1b PTC patients might be recommended in selected cases of multiple level involvement and macroscopic extranodal invasion requiring sacrifice of internal jugular vein, spinal accessory nerve, or sternomastoid muscle.

Axially vascularised mandibular constructs: Is it time for a clinical trial?

Applying regenerative therapies in the field of cranio-maxillofacial reconstruction has now become a daily practice. However, regeneration of challenging or irradiated bone defects following head and neck cancer is still far beyond clinical application. As the key factor for sound regeneration is the development of an adequate vascular supply for the construct, the current modalities using extrinsic vascularization are incapable of regenerating such complex defects. Our group has recently introduced the intrinsic axial vascularization technique to regenerate mandibular defects using the arteriovenous loop (AVL). The technique has shown promising results in terms of efficient vascularization and bone regeneration at the preclinical level. In this article, we have conducted a narrative literature review about using the AVL to vascularize tissue-engineering constructs at the preclinical level. We have also conducted a systematic literature review about applying the technique of axial vascularization in the field of craniofacial regeneration. The versatility of the technique and the possible challenges are discussed, and a suggested protocol for the first clinical trial applying the AVL technique for mandibular reconstruction is also presented.

Salvage of a free radial forearm flap by creation of an arteriovenous fistula at the distal arterial pedicle.

Interdisciplinary approaches with infrainguinal bypass grafts and free flaps between the plastic and vascular surgery may well offer an opportunity for diabetic patients with peripheral vascular disease to salvage their critically affected limbs. A free flap transfer combined with an autologous vein graft can cover large tissue defects and simultaneously improve distal perfusion even in patients with arterial occlusive disease. We are presenting a case of bypass-free radial forearm flap used to cover a foot defect in an old diabetic patient with peripheral arterial disease. The flap perfusion deteriorated significantly during the early postoperative period. The patient was brought back to the operating room with acute thrombosis of the popliteal-radial venous graft and the arterial pedicle of the flap. The flap was salvaged by thrombectomy and creation of an additional arteriovenous fistula at the distal arterial pedicle. The procedure improved the flap perfusion and decreased the high internal resistance that was noticed in the flap when trying to flush the radial artery during the revision surgery and was evident by continuous wave -Doppler sonography. The successful salvage of the flap in the presented case and the convenient long-term follow up suggest that this technique may be safe and helpful as a last effort to salvage a bypass-free flap with a suspected high internal resistance.

Mandibular reconstruction using an axially vascularized tissue-engineered construct.

BACKGROUND: Current reconstructive techniques for continuity defects of the mandible include the use of free flaps, bone grafts, and alloplastic materials. New methods of regenerative medicine designed to restore tissues depend mainly on the so-called extrinsic neovascularization, where the neovascular bed originates from the periphery of the construct. This method is not applicable for large defects in irradiated fields. METHODS: We are introducing a new animal model for mandibular reconstruction using intrinsic axial vascularization by the Arterio-Venous (AV) loop. In order to test this model, we made cadaveric, mechanical loading, and surgical pilot studies on adult male goats. The cadaveric study aimed at defining the best vascular axis to be used in creating the AV loop in the mandibular region. Mechanical loading studies (3 points bending test) were done to ensure that the mechanical properties of the mandible were significantly affected by the designed defect, and to put a base line for further mechanical testing after bone regeneration. A pilot surgical study was done to ensure smooth operative and post operative procedures. RESULTS: The best vascular axis to reconstruct defects in the posterior half of the mandible is the facial artery (average length 32.5 ± 1.9 mm, caliber 2.5 mm), and facial vein (average length 33.3 ± 1.8 mm, caliber 2.6 mm). Defects in the anterior half require an additional venous graft. The defect was shown to be significantly affecting the mechanical properties of the mandible (P value 0.0204). The animal was able to feed on soft diet from the 3rd postoperative day and returned to normal diet within a week. The mandible did not break during the period of follow up (2 months). CONCLUSIONS: Our model introduces the concept of axial vascularization of mandibular constructs. This model can be used to assess bone regeneration for large bony defects in irradiated fields. This is the first study to introduce the concept of axial vascularization using the AV loop for angiogenesis in the mandibular region. Moreover, this is the first study aiming at axial vascularization of synthetic tissue engineering constructs at the site of the defect without any need for tissue transfer (in contrast to what was done previously in prefabricated flaps).