Severe injuries to peripheral nerves are challenging to repair. Standard-of-care treatment for nerve gaps >2 to 3 centimeters is autografting; however, autografting can result in neuroma formation, loss of sensory function at the donor site, and increased operative time. To address the need for a synthetic nerve conduit to treat large nerve gaps, we investigated a biodegradable poly(caprolactone) (PCL) conduit with embedded double-walled polymeric microspheres encapsulating glial cell line–derived neurotrophic factor (GDNF) capable of providing a sustained release of GDNF for >50 days in a 5-centimeter nerve defect in a rhesus macaque model. The GDNF-eluting conduit (PCL/GDNF) was compared to a median nerve autograft and a PCL conduit containing empty microspheres (PCL/Empty). Functional testing demonstrated similar functional recovery between the PCL/GDNF-treated group (75.64 ± 10.28%) and the autograft-treated group (77.49 ± 19.28%); both groups were statistically improved compared to PCL/Empty-treated group (44.95 ± 26.94%). Nerve conduction velocity 1 year after surgery was increased in the PCL/GDNF-treated macaques (31.41 ± 15.34 meters/second) compared to autograft (25.45 ± 3.96 meters/second) and PCL/Empty (12.60 ± 3.89 meters/second) treatment. Histological analyses included assessment of Schwann cell presence, myelination of axons, nerve fiber density, and g-ratio. PCL/GDNF group exhibited a statistically greater average area occupied by individual Schwann cells at the distal nerve (11.60 ± 33.01 μm2) compared to autograft (4.62 ± 3.99 μm2) and PCL/Empty (4.52 ± 5.16 μm2) treatment groups. This study demonstrates the efficacious bridging of a long peripheral nerve gap in a nonhuman primate model using an acellular, biodegradable nerve conduit.
Objectives: The use of cone-beam computed tomography (CBCT) is well-established in clinical practice. This study seeks to categorize and quantify the incidental finding (IF) rate on CBCT in patients with cleft lip and palate (CLP) prior to orthodontic or surgical treatment. Methods: This is systematic retrospective review of head and neck CBCTs in patients with nonsyndromic CLP taken between 2012 and 2019 at a single tertiary referral center. All assessments were performed independently by 4 observers (a head and neck radiologist and 3 orthodontists, including 2 fellowship-trained cleft-craniofacial orthodontists ). The images were divided into 9 anatomical areas and screened using serial axial slices and 3D reconstructions. The absolute number of IFs was reported for each area and statistical analysis was performed. Results: Incidental findings were found in 106 (95.5%) of the 111 patients. The most common sites were the maxilla (87.4%, principally dental anomalies), paranasal sinuses (46.8%, principally inflammatory opacification), and inner ear cavities (18.9%, principally inflammatory opacification). Eleven patients had skull malformations. Thirty-three patients had IFs in 1 anatomical area, 49 patients in 2 anatomical areas, 19 patients in 3 areas, and 5 patients presented with IFs in 4 of the 9 anatomical areas. Discussion: In patients with CLP, IFs on CBCT exam were present in the majority of cases. Most patients with IFs had them in multiple anatomical areas of the head and neck. The maxillary dental–alveolar complex was the most common area. Inflammatory changes in the inner ear cavities and paranasal sinuses were also common; however, cervical spine and skull abnormalities were also identified. Clinicians caring for patients with CLP should be aware of IFs, which may warrant further investigation and treatment.
Background: The submucous cleft palate can be overt or occult and may require surgical repair. The double-opposing Z-plasty (Furlow repair) is the authors’ center’s preferred approach. This study evaluated complication rates, differences in outcome between overt and occult types, and patient factors associated with surgical failure. Methods: This retrospective study reviewed documentation on all patients who underwent Furlow Z-plasty for submucous cleft palate at a single center between 2004 and 2018. Speech pathology was quantified using the Pittsburgh Weighted Speech Score. Results: A total of 351 patients were included (125 overt and 226 occult cases). Furlow Z-plasty was successful (postoperative Pittsburgh Weighted Speech Score <7 without recommendation for secondary speech surgery) in 291 patients (82.1 percent). Apart from those requiring secondary surgery, there were no documented complications. Occult-type patients were 7.5 years old at palatoplasty with a speech score of 14.1; overt-type patients were 6.5 years old with a score of 15.7. Postoperative speech scores were similar for both groups. Secondary speech surgery patients had a higher preoperative score (16.9 versus 14.2). Age at time of palatoplasty and submucous cleft palate type were not predictive of the need for secondary surgery. Syndromic patients had higher preoperative and postoperative speech scores (15.6 and 7.5, respectively) than nonsyndromic patients (14.3 and 4.3) and needed secondary surgery more often (24.4 percent versus 9.2 percent). V-shaped velar vaulting on preoperative assessment was present in 92 percent of occult-type patients. Conclusions: Furlow palatoplasty is a safe and effective means of repairing submucous cleft palate. Patients with the occult type presented later with a lower Pittsburgh Weighted Speech Score. High preoperative speech score and syndromic status were associated with the need for secondary speech surgery. V-shaped velar vaulting is a reliable sign of occult submucous cleft palate. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.
In just over 100 years, surgical education in the United States has evolved from a disorganized practice to a refined system esteemed worldwide as one of the premier models for the training of physicians and surgeons. But in the changing environment of health care, new challenges have arisen that could warrant a reform. To design our future, we must understand our past. The present work is not intended to be a comprehensive account of the history of American surgery. Instead, it tells the abridged history of surgical education in our country: the evolution from apprenticeships to residencies; the birth of hospital-based teaching; the impact of key historical events on training; the marks left by some preeminent characters; the conception of regulatory entities that steer our education; and, finally, how our process of training surgeons might need to be refined for the continued progress of our profession. Told in chronological order in a manner that will be memorable to readers, this story weaves together the key events that explain how our current surgical training models came to be. We conclude with a timely invitation to draw from these past lessons to redesign the future of graduate medical education, making a case for the transition to time-variable, competency-based medical education for surgical residency programs in America.
Fat grafting was first described in the early 20th century but for many years remained a relatively underused technique due to the unreliability of long-term volume expansion. Significant improvements in reliability have been made in the last 2 decades and there is a large body of literature pertaining to extraction, processing and injection methods to obtain more lasting effects. However, volume loss and graft resorption remain a major challenge in the long term and lead to unpredictability in results. Enriching adipose graft with stromal vascular fraction, ex vivo cultured adipose stem cells and platelet-derived growth factor among others is one method under active investigation which may assist graft survival through a range of mechanisms including increased angiogenesis. Breaking adipose graft into smaller fragments such that engrafted cells have greater access to donor-site oxygenation and nutrition is another method which in theory may promote survival. Presently, adipose grafting in the face is usually for the addition of volume to fill defects. However, the stem-cell containing fraction of adipose grafting (stromal vascular fraction) appears to exert a rejuvenating effect on overlying skin and soft tissue when administered alone. The application of these low-volume injections represents a significant shift in thinking away from mere volume expansion. These techniques have been tested in a range of animal models and some human studies. In this review, the authors provide a broad overview of present research and highlight both limitations in previous research and current areas of investigation.
Pierre Robin Sequence (PRS) can be associated with skeletal dysplasias, presenting with craniocervical instability and devastating spinal injury if unrecognized. The authors present the case of an infant with PRS and a type II collagenopathy who underwent multiple airway-securing procedures requiring spinal manipulation before craniocervical instability was identified. This resulted in severe cervical cord compression due to odontoid fracture and occipitoatlantoaxial instability. This case highlights the importance of early cervical spine imaging and cautious manipulation in infants with PRS and suspected skeletal dysplasia.
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