Pedicled Vascularized Flap Research Articles

Fat graft in cerebrospinal fluid leak repair after sellar and parasellar lesion surgery of 2000 patients; a multicenter study

IntroductionThis study investigates the outcome of cerebrospinal fluid leakage repair after endoscopic transsphenoidal surgery (ETSS) sellar and parasellar lesions with fat graft. Method and materialsThis is a cross-sectional study designed to evaluate the results of sellar and parasellar repair with simplified method of using only fat graft as the primary choice in patients undergoing ETSS surgery at three referral hospitals between 2011 and 2021. ResultsIn 2000 sellar and parasellar transsphenoidal surgeries, 860 patients had intraoperative CSF leak and were repaired to stop CSF leak mostly with fat graft only. 58 patients came back with delayed cerebrospinal fluid leak. Of these, 21 patients did not have intraoperative leak with no primary surgical repair but came back with a delayed CSF leak. Repair method for 37 ‘re-leak’ cases was fat in 29 patients, fat with fascia and/or nasoseptal flap for the rest of them. The success rate was 96.3% for intraoperative leaks that were primarily managed with fat graft alone. ConclusionOur study suggests that fat graft can be considered a reliable material for sellar reconstruction which is easy to harvest and use, regardless of the type of leak flow (high vs low). Using other materials or more complex multilayer methods such as facial grafts or pedicled vascularized flaps are advisable choices for unusual and very large defects or secondary postoperative CSF leaks.

Risk factors for postoperative CSF leakage after endonasal endoscopic skull base surgery: a meta-analysis and systematic review.

Cerebrospinal fluid (CSF) leakage is a complication that any surgeon working in the field of skull base surgery does not wish to encounter. The surgical approach to the skull base often varies, and the various sizes and locations of skull base lesions make it difficult to determine the cause of CSF leakage. However, it is useful to investigate which factors contribute to postopera- tive CSF leakage. Related studies were identified by searching the following databases: PubMed/Medline, Embase, and Web of Sciences through December 2019. Random-effects models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). The Newcastle-Ottawa scale was used to evaluate the quality of observational studies. Our search yielded 56 retrospective cohort studies involving a total of 11,826 skull base surgical procedures. The overall rate of postoperative CSF leakage was 7.2%. The effect of obesity on postoperative CSF leakage had an OR of 1.88, and the effect of perioperative radiotherapy on postoperative CSF leakage yielded an OR of 1.87. High intraoperative CSF flow rate also had a significant OR of 2.98. On the other hand, a pedicled vascularized flap efficiently reduced the risk of postoperative CSF leakage. Defect size and the presence or absence of a lumbar drain had no effect on postoperative CSF leakage. This comprehensive quantitative assessment of postoperative CSF leakage showed that obesity, perioperative radiotherapy, and high intraoperative CSF flow rate raised the risk of CSF leakage; however, a pedicled vascularized flap can ef- fectively reduce the risk of postoperative CSF leakage.

Quantitative determination of the optimal temporoparietal fascia flap necessary to repair skull-base defects.

The ability to reconstruct large cranial base defects has greatly improved with the development of pedicled vascularized flaps. The temporoparietal fascia flap (TPFF) is a viable alternative to the Hadad-Bassagasteguy nasoseptal flap for large ventral skull-base defects. This study aims to characterize the size of the TPFF necessary for optimal ventral skull-base reconstruction. Eleven formaldehyde-fixed cadaveric heads were used to harvest TPFF of varying heights on each side (total = 22). TPFF was passed through the pterygomaxillary fissure (PMF) to the ventral skull base to assess its coverage. For a subgroup of 12 sides, the TPFF was trimmed to determine the minimum height necessary for coverage. The TPFF height was (mean ± standard deviation [SD]) 14.72 ± 1.02 cm (range, 12.5 to 16.5 cm) and width was 8.43 ± 1.05 cm (range, 6 to 10.5 cm). The distance from the TPFF pedicle through the PMF was 5.8 ± 0.5 cm (range, 5 to 6.5 cm). All TPFF flaps provided complete ipsilateral coverage of clival defects, and all but 1 covered the entire clivus. All TPFF flaps, when rotated anteriorly, provided coverage up to the cribriform plate. The minimum TPFF height necessary for complete coverage of cribriform defects and ventral defects up to the planum sphenoidale was 12 cm. TPFF height for specimens with and without complete ventral skull-base coverage was significantly different (p < 0.0001). The TPFF is a versatile alternative to the nasoseptal flap and a height of at least 12 cm can provide enough coverage for all ventral skull base defects.

Endoscopic Endonasal Reconstructive Methods to the Anterior Skull Base

The success of expanded endoscopic endonasal approaches (EEAs) to the anterior skull base, sellar, and parasellar regions has been greatly aided by the advancement in reconstructive techniques. In particular, the pedicled vascularized flaps have been developed and effectively cover skull base defects of varying sizes with a significant reduction in postoperative CSF leaks. There are two aims to this review: (1) We will provide our current, simplified reconstruction algorithm. (2) We will describe, in detail, the relevant anatomy, indications/contraindications, and surgical technique, with a particular emphasis on the nasoseptal flap (NSF). The inferior turbinate flap (ITF), middle turbinate flap (MTF), pericranial flap (PCF), and temporoparietal fascial flap (TPFF) will also be described. The NSF should be the primary option for reconstruction of majority of skull base defects following endonasal endoscopic surgery. In general, for the planum, cribriform, and upper two-thirds of the clivus, the NSF is ideal. For the lower-third of the clivus, the NSF may not be adequate and may require additional reconstructive options. Although limited in reach or more technically challenging, these reconstructive flaps should still be considered and kept in the surgical algorithm.

Risk factors associated with postoperative cerebrospinal fluid leak after endoscopic endonasal skull base surgery.

OBJECTIVE The aim in this paper was to determine risk factors for the development of a postoperative CSF leak after an endoscopic endonasal approach (EEA) for resection of skull base tumors. METHODS A retrospective review of patients who underwent EEA for the resection of intradural pathology between January 1997 and June 2012 was performed. Basic demographic data were collected, along with patient body mass index (BMI), tumor pathology, reconstruction technique, lumbar drainage, and outcomes. RESULTS Of the 615 patients studied, 103 developed a postoperative CSF leak (16.7%). Sex and perioperative lumbar drainage did not affect CSF leakage rates. Posterior fossa tumors had the highest rate of CSF leakage (32.6%), followed by anterior skull base lesions (21.0%) and sellar/suprasellar lesions (9.9%) (p < 0.0001). There was a higher leakage rate for overweight and obese patients (BMI > 25 kg/m2) than for those with a healthy-weight BMI (18.7% vs 11.5%; p = 0.04). Patients in whom a pedicled vascularized flap was used for reconstruction had a lower leakage rate than those in whom a free graft was used (13.5% vs 27.8%; p = 0.0015). In patients with a BMI > 25 kg/m2, the use of a pedicled flap reduced the rate of CSF leakage from 29.5% to 15.0% (p = 0.001); in patients of normal weight, this reduction did not reach statistical significance (21.9% [pedicled flap] vs 9.2% [free graft]; p = 0.09). CONCLUSIONS Preoperative BMI > 25 kg/m2 and tumor location in the posterior fossa were associated with higher rates of postoperative CSF leak. Use of a pedicled vascularized flap may be associated with reduced risk of a CSF leak, particularly in overweight patients.

The application of a free nasal floor mucoperiosteal graft in endoscopic sinus surgery.

Numerous reconstructive techniques and materials have been reported for repair of skull base defects, cerebrospinal fluid (CSF) leaks, and coverage of denuded bone, including pedicled vascularized flaps and free mucosal grafts. This study described our technique of harvesting and transferring a free nasal floor mucoperiosteal graft and discussed our experience with the application of this technique. A retrospective review of 19 patients (mean age, 53.7 years; 13 men, 6 women) treated with image-guided endoscopic sinus surgery for chronic rhinosinusitis or tumors. Intraoperative free mucosal graft repair was performed for large skull base defects after resection of skull base tumor (n = 7), CSF leak (n = 12), and iatrogenic CSF leak (n = 7). Repair was performed in an overlay or an underlay fashion, with a multilayer approach in cases of a large skull base defect. Patients underwent endoscopic assessment at 6 days, 5 weeks, and 12 weeks after surgery for assessment of healing and of CSF leak. The patients were followed up for a mean of 8.7 months. Minimal crusting was identified at the donor site in all the patients at 6 days, with no evidence of CSF leak. In cases of exposed bone and/or mucosal stripping, hyperostosis at the recipient graft site was avoided. All the patients had complete healing at the donor site and the recipient site, with minimal morbidity at 5 and 12 weeks, and no evidence of recurrent CSF leak. The use of nasal floor mucoperiosteal free grafts in endoscopic surgery offered the advantage of ease of harvest, coverage of large defects, and multiple applications of use, with minimal donor-site morbidity.

Surgical anatomy and utility of pedicled vascularized tissue flaps for multilayered repair of skull base defects.

OBJECT The objective of this study was to describe the surgical anatomy and technical nuances of various vascularized tissue flaps. METHODS The surgical anatomy of various tissue flaps and their vascular pedicles was studied in 5 colored silicone-injected anatomical specimens. Medical records were reviewed of 11 consecutive patients who underwent repair of extensive skull base defects with a combination of various vascularized flaps. RESULTS The supraorbital, supratrochlear, superficial temporal, greater auricular, and occipital arteries contribute to the vascular supply of the pericranium. The pericranial flap can be designed based on an axial blood supply. Laterally, various flaps are supplied by the deep or superficial temporal arteries. The nasoseptal flap is a vascular pedicled flap based on the nasoseptal artery. Patients with extensive skull base defects can undergo effective repair with dual flaps or triple flaps using these pedicled vascularized flaps. CONCLUSIONS Multiple pedicled flaps are available for reconstitution of the skull base. Knowledge of the surgical anatomy of these flaps is crucial for the skull base surgeon. These vascularized tissue flaps can be used effectively as single or combination flaps. Multilayered closure of cranial base defects with vascularized tissue can be used safely and may lead to excellent repair outcomes.

Reconstruction of the rabbit trachea with vascularized auricular perichondrium.

Success in laryngotracheal reconstruction has been limited, in part, by the lack of an ideal grafting material. Perichondrium is thin, pliable, and highly vascularized and has the ability to generate new cartilage providing rigid support. These qualities make vascularized perichondrium potentially the ideal grafting material for circumferential airway stenosis. A pedicled vascularized flap of auricular perichondrium was used in a rabbit model (n = 39) to reconstruct a near-circumferential tracheal defect without a tracheostomy. A stent was used to support the reconstructed airway for 6 weeks, after which time it was removed by direct laryngoscopy. Animals were observed for an additional 6 weeks prior to sacrifice. Qualitative and quantitative histologic analysis of neochondrogenesis is reported. Vascularized perichondrium and periosteum show promise as potential grafts for reconstruction of circumferential tracheal defects.