Wedge resection combined with 3D-printed polycaprolactone mesh for caudal septal deviation.

BACKGROUND: Biocompatibility and stability of three-dimensional printed polycaprolactone mesh grafts for nasal surgery are proven in both animal and human models. However, their safety and durability as batten grafts for caudal septal deviation has not been documented. This study was designed to investigate the efficacy and safety of three-dimensional printed polycaprolactone mesh batten graft in septoplasty using the wedge resection technique for the correction of caudal septal deviation. METHODS: This retrospective study reviewed the medical records of 20 patients aged ≥ 18 years with caudal septal deviation who underwent septoplasty with wedge resection and three-dimensional printed polycaprolactone mesh graft from a tertiary medical center in South Korea, between December 1, 2019 and May 31, 2021. Those without nasal obstruction before surgery or with a short follow-up period (< 28 days) were excluded from the survey analysis. RESULTS: Of the 20 patients (mean age, 48.0 [range, 19-65] years), 17 (85.0%) were male, and three (15.0%) were female. A significant change was noted in the mean nasal obstruction symptom evaluation score (68.2 vs. 15.0, P < .001) in the 17 patients included in the analysis. Postoperative endoscopic evaluation revealed a straight septum in 19/20 (95.0%) patients, and no complications were noted in the postoperative follow-up period of up to 364 days. CONCLUSIONS: The three-dimensional printed polycaprolactone nasal mesh is safe and provides adequate support to resist the intrinsic memory of the cartilage of the caudal septum. In addition to nasal surgeries, it has great potential as a graft in other reconstructive surgeries. Trial registration Retrospectively registered.

A new histopathological location of parathyroid gland with high possibility of unintended parathyroidectomy.

Background: Unintended parathyroidectomy occasionally happens despite meticulous capsular dissection and the histopathological location of removed parathyroid glands were traditionally classified as extracapsular, subcapsular, and intrathyroidal location. This study aimed to investigate the new histopathological location of parathyroid gland with high possibility of unintended parathyroidectomy that was difficult to be found with naked eye despite capsular dissection. Methods: This study investigated unintended parathyroidectomy that occurred in 743 patients who received thyroid surgery by reviewing pathology reports and slides. The histopathological location of unintentionally removed parathyroid glands was classified as intracapsule and extracapsule, and the intracapsular glands were further classified as completely buried in the thyroid parenchyme, partially buried, and subcapsular locations. Results: The incidence of unintended parathyroidectomy was 12.8%. Among the 103 unintentionally removed parathyroid glands, 74 (71.8%) were found intracapsular and 29 were extracapsular. Among the intracapsular glands, 57 (55.4%) parathyroid glands were found in difficult locations such as completely buried (40.8%) and partially buried (14.6%). Conclusions: The partially buried parathyroid gland can act as a risk factor for unintended parathyroidectomy comparable to intrathyroidal parathyroid gland despite the surgeon's best effort with meticulous capsular dissection. However, continued advances in visualizing technique such as autofluorescence imaging may lower the chance of incidentally removed partially buried parathyroid glands in the future.

Ultrasonographic and Surgical Findings of Acute Radial Neuropathy Following Blunt Trauma.

Ultrasonographic study is useful for decision making of treatment for focal neuropathy with unusual electrodiagnostic findings. We present a patient with severe acute radial neuropathy with sensory sparing around the distal arm secondary to twisting of the radial nerve following blunt trauma. A 24-year-old man with a 2-week history of left wrist drop and severe pain around the left elbow presented after hitting the left distal arm on the doorknob. The left wrist and finger extensions were grade 0, but elbow extension could not be tested because of severe pain during this action. The left superficial radial sensory territory was intact. Electrodiagnostic findings suggested severe left radial neuropathy around the distal arm with sensory sparing. Ultrasonographic study demonstrated 2 stenotic lesions around the distal arm and absence of the left superficial radial sensory nerve. Surgical exploration revealed 2 stenotic lesions with twisting of the nerve, concordant with ultrasonographic study. End-to-end anastomosis was performed in the proximal lesion. Sixteen months later, wrist and finger extension was grade 3, and reinnervation signs in the radial-innervated muscles except extensor indicis muscle were observed. The complementary relationship between electrophysiologic and ultrasonographic examinations is very important for precise lesion location and decision making for treatment of peripheral nerve injury.

Molecularly engineered nanocomposites: layer-by-layer assembly of cellulose nanocrystals.

Cellulose nanocrystals are promising as a new class of reinforcing material for the preparation of nanostructured composites. We report here the preparation of cellulose nanocrystal multilayer composites with poly(diallyldimethylammonium chloride) using layer-by-layer assembly (LBL) technique. The LBL assembly was characterized with UV-Vis spectroscopy and ellipsometry. The average thickness of a single bilayer was found to be 11 nm. AFM and SEM characterization revealed uniform coverage and densely packed cellulose crystal surface.