Review of skull base reconstruction using locoregional flaps and free flaps in children and adolescents

Identification of the anatomy of the deep temporal vein using computed tomography imaging: A retrospective cross-sectional review of patient imaging

PURPOSE

The deep temporal vein (DTV) can be used in free flap procedures when the superficial temporal vein is inadequate. Despite its potential utility, its branching patterns have only been examined in one small anatomic study. The purpose of this study was to examine computed tomography angiography (CTA) images to determine DTV location, variation, and suitability as a microvascular recipient, to provide surgeons with a guide for its use in head and neck defects.

METHODS

A retrospective chart review identified 152 patient CTA images (76 female; 76 male) in a single academic center imaging database, selected consecutively from January 2017 to April 2020. Patients under 19 years were excluded; ages ranged from 19 to 80 years (average 51.6 years). Reason for imaging, DTV caliber, laterality, distance to zygomatic arch (ZA [coronal and sagittal]), distance to lateral orbital rim (LOR), and branching pattern were recorded.

RESULTS

The predominant reason for imaging was to rule out cerebrovascular accident (96.2%). Average caliber was 3.46 ± 1.29 mm (95% confidence interval [CI] [3.32, 3.61]; range, 1.00-10.8). Bilateral DTVs were observed in 98.7% of patients. Average distance to landmarks were as follows: ZA (coronal), 13.8 ± 5.85 mm (95% CI [13.2, 14.5]; range, 2.7-33.8); ZA (sagittal), 15.1 ± 6.12 mm (95% CI [14.1, 16.1]; range, 2.8-47.2); LOR, 47.1 ± 9.09 mm (95% CI [46.0, 48.1]; range, 10.8-62.9). Seven branching patterns were identified, including a posterior vertical variant that bypasses the superficial temporal fat pad.

CONCLUSIONS

The DTV is a "lifeboat" option for head and neck reconstruction. Its average caliber is sufficient for use in microsurgery. Knowledge of both its typical and aberrant courses allow for efficient preoperative planning and surgical dissection. CTA is a useful adjunct when planning to use the DTV for free tissue transfer.

Surgical treatment of pediatric rhabdomyosarcoma in the parameningeal-nonparameningeal region

OBJECTIVES

Rhabdomyosarcoma (RMS) involving the parameningeal-nonparameningeal region (PNP) is relatively rare in pediatric patients (PPs). The current study aimed to report the outcomes of RMS-PNP-PPs who received surgical resection combined with concurrent flap reconstruction.

METHODS

A retrospective study was conducted concerning RMS-PNP-PPs who received combined skull-maxillofacial resection with flap reconstruction during the period from 2012 to 2016. Predictive factors for recurrence-free survival (RFS), metastasis-free survival (MFS), and overall survival (OS) were preliminarily identified by Kaplan-Meier analysis.

RESULTS

A total of 16 RMS-PNP-PPs were finally enrolled; recurrence, metastasis and death were found in 7, 7 and 5 patients, respectively. Following surgical ablation involving the skull base and maxillofacial region, reconstruction was performed with a local flap in 9 patients, a latissimus dorsi flap in 3 patients, and an anterolateral thigh flap in 4 patients. Through univariate analysis, we demonstrated that the primary site + surgical margins, postoperative RT/CT + Ki-67/Bcl-2 IHC, and surgical margins + Ki-67/Bcl-2 IHC could be used as the preliminarily prognostic factors for RFS, MFS and OS, respectively.

CONCLUSIONS

RMS-PNP-PPs showed poor prognosis even when surgical resection combined with flap reconstructions was performed. Achieving a clear surgical margin and good conduction of postoperative RT/CT should be taken into consideration to acquiring a better surgical outcome.

Free flaps for head and neck cancer in paediatric and neonatal patients

PURPOSE OF REVIEW

To review recent literature on the subject of free tissue transfer options in paediatric head and neck surgery, with a particular emphasis on highlighting the advantages and disadvantages of different reconstructions in the paediatric patient.

RECENT FINDINGS

Free tissue transfer in paediatric patients is predictable and applicable for a wide range of congenital and acquired defects in the head and neck. The free fibula flap is a mainstay of mandibular reconstruction and allows excellent implant-supported prosthodontic rehabilitation and growth potential at the recipient site with little or no donor site morbidity. Other less commonly explored options include the deep circumflex iliac artery flap, scapula flap and medial femoral condyle flap. The gracilis mucle remains the mainstay for facial reanimation with other options including pectoralis minor, rectus abdominis, extensor digitorum brevis and latissimus dorsi. There are compelling arguments for centralization of services and creative strategies in postoperative rehabilitation (e.g. play therapy).

SUMMARY

Free flaps in paediatric patients are a viable option and may even have advantages relative to adults because of the absence of atherosclerosis, purported lower risk of vasospasm and proportionally larger vessel size. Transfer earlier in life maximizes functional potential and 'normalizes' treatment.

Surgical Interventions for Advanced Parameningeal Rhabdomyosarcoma of Children and Adolescents

Owing to its rarity, rhabdomyosarcoma of the head and neck (HNRMS) has seldom been discussed in the literature. As most of the data is based only on the retrospective experiences of tertiary healthcare centers, there are difficulties in formulating a standard treatment protocol. Moreover, the disease is poorly understood at its pathological, genetic, and molecular levels. For instance, 20% of all histological assessment is inaccurate; even an experienced pathologist can confuse rhabdomyosarcoma (RMS) with neuroblastoma, Ewing’s sarcoma, and lymphoma. RMS can occur sporadically or in association with genetic syndromes associated with predisposition to other cancers such as Li-Fraumeni syndrome and neurofibromatosis type 1 (von Recklinghausen disease). Such associations have a potential role in future gene therapies but are yet to be fully confirmed. Currently, chemotherapies are ineffective in advanced or metastatic disease and there is lack of targeted chemotherapy or biological therapy against RMS. Also, reported uses of chemotherapy for RMS have not produced reasonable responses in all cases. Despite numerous molecular and biological studies during the past three decades, the chemotherapeutic regimen remains unchanged. This vincristine, actinomycin, cyclophosphamide (VAC) regime, described in Kilman, et al. (1973) and Koop, et al. (1963), has achieved limited success in controlling the progression of RMS. Thus, the pathogenesis of RMS remains poorly understood despite extensive modern trials and more than 30 years of studies exploring the chemotherapeutic options. This suggests a need to explore surgical options for managing the disease. Surgery is the single most critical therapy for pediatric HNRMS. However, very few studies have explored the surgical management of pediatric HNRMS and there is no standard surgical protocol. The aim of this review is to explore and address such issues in the hope of maximizing the number of options available for young patients with HNRMS.

Skull Base Reconstruction in the Pediatric Patient

Introduction  Pediatric skull base and craniofacial reconstruction presents a unique challenge since the potential benefits of therapy must be balanced against the cumulative impact of multimodality treatment on craniofacial growth, donor-site morbidity, and the potential for serious psychosocial issues. Objectives  To suggest an algorithm for skull base reconstruction in children and adolescents after tumor resection. Materials and Methods  Comprehensive literature review and summary of our experience. Results  We advocate soft-tissue reconstruction as the primary technique, reserving bony flaps for definitive procedures in survivors who have reached skeletal maturity. Free soft-tissue transfer in microvascular technique is the mainstay for reconstruction of large, three-dimensional defects, involving more than one anatomic region of the skull base, as well as defects involving an irradiated field. However, to reduce total operative time, intraoperative blood loss, postoperative hospital stay, and donor-site morbidity, locoregional flaps are better be considered the flap of first choice for skull base reconstruction in children and adolescents, as long as the flap is large enough to cover the defect. Our "workhorse" for dural reconstruction is the double-layer fascia lata. Advances in endoscopic surgery, image guidance, alloplastic grafts, and biomaterials have increased the armamentarium for reconstruction of small and mid-sized defects. Conclusions  Skull base reconstruction using locoregional flaps or free flaps may be safely performed in pediatrics. Although the general principles of skull base reconstruction are applicable to nearly all patients, the unique demands of skull base surgery in pediatrics merit special attention. Multidisciplinary care in experienced centers is of utmost importance.

Esthetic Craniofacial Bony and Skull Base Reconstruction Using Flap Wrapping Technique

For a safe and esthetic skull base reconstruction combined with repair of craniofacial bone defects, the authors introduce the flap wrapping technique in this study. This technique consists of skull base reconstruction using the vastus lateralis muscle of an anterolateral thigh (ALT) free flap, and structural craniofacial bony reconstruction using an autologous calvarial bone graft. The key to this technique is that all of the grafted autologous bone is wrapped with the vascularized fascia of the ALT free flap to protect the grafted bone from infection and exposure. Two anterior skull base tumors combined with craniofacial bony defects were included in this study. The subjects were a man and a woman, aged 18 and 64. Both patients had preoperative proton beam therapy. First, the skull base defect was filled with vastus lateralis muscle, and then structural reconstruction was performed with an autologous bone graft and a fabricated inner layer of calvarial bone, and then the grafted bone was completely wrapped in the vascularized fascia of the ALT free flap. By applying this technique, there was no intracranial infection or grafted bone exposure in these 2 patients postoperatively, even though both patients had preoperative proton beam therapy. Additionally, the vascularized fascia wrapped bone graft could provide a natural contour and prevent collapse of the craniofacial region, and this gives patients a better facial appearance even though they have had skull base surgery.

Galea and periosteum flap filled with bone fragments in rabbits

PURPOSE

To study the bone viability of a vascularized galea and periosteum flap filled with bone fragments, as a substitute of the bone graft in facial reconstructive surgery.

METHODS

Forty rabbits were studied, and divided in two groups. One had a simple galea and periosteum flap done and the other had the same flap done and filled with bone fragments of the calvaria. The bone formation was evaluated by radiographies, macroscopic and microscopic analysis.

RESULTS

The bone neoformation in both groups with differences in bone morphology and structure especially at histological analysis.

CONCLUSION

This study demonstrated osseous formation in both groups of galea and periosteum flaps, with and without bone fragments.