Microvascular reconstruction of the skull base: a clinical approach to surgical defect classification and flap selection.

Skull-base tumor resection and reconstruction produce a major physiologic and anatomic impact on the patient. At our institution, the use of vascularized, free-tissue transfer has replaced pedicled flaps as the preferred modality for reconstructing complex cranial base defects involving resection of dura, brain, or multiple major structures adjacent to skull base, including the orbit, palate, mandible, skin, and other structures. The goals of reconstruction are to: (1) support the brain and orbit; (2) separate the CNS from the aerodigestive tract; (3) provide lining for the nasal cavity; (4) re-establish the nasal and oropharyngeal cavities; (5) provide volume to decrease dead space; and (6) restore the three-dimensional appearance of the face and head with bone and soft tissues. Surgical management requires a multidisciplinary effort with collaborating neurosurgical, head and neck, and plastic surgical teams. Successful reconstruction of skull base defects is predicated upon a careful appreciation of the specific region. Defects may be classified based on their anatomic location and loss of volume, support, and skin cover. Free flaps provide reliable, well-vascularized soft tissue to seal the dura, obliterate dead space, cover exposed cranial bone, and provide cutaneous coverage for skin or mucosa.

New directions in bioabsorbable technology.

Generating replacement tissues requires an interdisciplinary approach that combines developmental, cell, and molecular biology with biochemistry, immunology, engineering, medicine, and the material sciences. Because basic cues for tissue engineering may be derived from endogenous models, investigators are learning how to imitate nature. Endogenous models may provide the biological blueprints for tissue restoration, but there is still much to learn. Interdisciplinary barriers must be overcome to create composite, vascularized, patient-specific tissue constructs for replacement and repair. Although multistep, multicomponent tissue fabrication requires an amalgamation of ideas, the following review is limited to the new directions in bioabsorbable technology. The review highlights novel bioabsorbable design and therapeutic (gene, protein, and cell-based) strategies currently being developed to solve common spine-related problems.

New directions in bioabsorbable technology.

Generating replacement tissues requires an interdisciplinary approach that combines developmental, cell, and molecular biology with biochemistry, immunology, engineering, medicine, and the material sciences. Since the basic cues for tissue engineering may be derived from endogenous models, investigators are learning how to imitate nature. Endogenous models may provide the biologic blueprints for tissue restoration, but there is still much to learn. Interdisciplinary barriers must be overcome to create composite, vascularized, patient-specific tissue constructs for replacement and repair. Although multistep, multicomponent tissue fabrication requires an amalgamation of ideas, the following review is limited to the new directions in bioabsorbable technology. The review highlights novel bioabsorbable design and therapeutic (gene, protein, and cell-based) strategies that are currently being developed to solve common spinal problems.

A 15-year review of midface reconstruction after total and subtotal maxillectomy: part I. Algorithm and outcomes.

BACKGROUND: Reconstruction of complex midfacial defects is best approached with a clear algorithm. The goals of reconstruction are functional and aesthetic. METHODS: Over a 15-year period (1992 to 2006), a single surgeon (P.G.C.) performed 100 flaps to reconstruct the following midfacial defects: type I, limited maxillectomy (n = 20); type IIA, subtotal maxillectomy with resection of less than 50 percent of the palate (n = 8); type IIB, subtotal maxillectomy with resection of greater than 50 percent of the palate (n = 8); type IIIA, total maxillectomy with preservation of the orbital contents (n = 22); type IIIB, total maxillectomy with orbital exenteration (n = 23); and type IV, orbitomaxillectomy (n = 19). Free flaps were used in 94 cases (94 percent), and pedicled flaps were used in six (6 percent). RESULTS: One hundred flaps were performed in 96 patients (69 males, 72 percent; 27 females, 28 percent); four patients underwent a second flap reconstruction due to recurrent disease (n = 4, 4 percent). Average patient age was 49.2 years (range, 13 to 81 years). Free-flap survival was 100 percent, with one partial flap loss (1 percent). Five patients suffered systemic complications (5.2 percent), and four died within 30 days of hospitalization (4.2 percent). Over 50 percent of patients returned to normal diet and speech. Almost 60 percent were judged to have an excellent aesthetic result. CONCLUSIONS: Free-tissue transfer offers the most effective and reliable form of reconstruction for complex maxillectomy defects. Rectus abdominis and radial forearm free flaps in combination with immediate bone grafting or as osteocutaneous flaps consistently provide the best functional and aesthetic results. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

A 15-year review of midface reconstruction after total and subtotal maxillectomy: part II. Technical modifications to maximize aesthetic and functional outcomes.

BACKGROUND: Midface reconstruction of oncologic defects is one of the most challenging problems in plastic surgery. Over time, the senior author (P.G.C.) has developed modifications in his technique for oncologic midface reconstruction to minimize complications and maximize outcomes. METHODS: Over a 15-year period (1992 to 2006), 100 flaps for midface oncologic reconstruction were performed at Memorial Sloan-Kettering Cancer Center. The first 50 flaps were performed from 1992 to 2000, and the second 50 flaps were performed from 2001 to 2006. Over time, technical improvements were made in the following areas: palate, dental implants and prosthesis, orbital floor, eyelid, nasal sidewall, lips, cranial base and dura, and pedicle anastomosis. Using a prospectively maintained database, the authors compared the functional and aesthetic outcomes of the first 50 flaps and the second 50 flaps. RESULTS: Improvements in palatal reconstruction increased the proportion of patients who achieved normal speech from 38.9 percent in the first half of the series (1992 to 2000) to 50 percent in the second half of the series (2001 to 2006). The percentage of patients who were able to tolerate an unrestricted diet increased from 44.4 to 52 percent. The use of new methods to reconstruct the orbital floor also lowered the ectropion rate from 71.4 to 47.6 percent. The percentage of patients whose aesthetic results were judged as "excellent" increased from 12 to 58.6 percent. CONCLUSIONS: Over the last 15 years, the senior author has refined methods of midface reconstruction that have improved functional and aesthetic outcomes. These technical advancements have made it possible to obtain better and more consistent results. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.