Laryngeal granulomas in patients after two-jaw surgery - Four cases report.

BACKGROUND: Endotracheal intubation can cause focal ischemia, damage or edema to the laryngeal mucosa, and may be followed by serious complications such as vocal cord paralysis, ulcers, and granulation tissue formation. Laryngeal granuloma is rare but also a significant late complication of endotracheal intubation, and anesthesiologists should be concerned about it. CASE: We experienced four cases of laryngeal granuloma that developed after two-jaw surgery January 2017-December 2018 in our hospital and would like to report these cases with brief review of literature. CONCLUSIONS: There are frequent movements on the head and neck in maxillofacial surgery and the nasotracheal intubation should be prolonged after bimaxillary osteotomy surgery because of post-operative airway problems. This may be why two-jaw surgery may have higher occurrence of laryngeal granuloma than others.

Retro-Odontoid Pseudotumor without Atlantoaxial Subluxation or Rheumatic Arthritis.

We present a case of retro-odontoid pseudotumor (ROP) without rheumatoid arthritis (RA) or atlantoaxial subluxation (AAS). A 76-year-old woman presented with paresthesia and weakness of both lower and upper extremities. She had no laboratory or physical findings of RA. Dynamic X-ray showed no AAS and magnetic resonance imaging (MRI) showed a retro-odontoid mass compressing the spinal cord. Transdural mass debulking and biopsy were performed via minimal left suboccipital craniectomy and C1 hemilaminectomy. Two months after surgery, her symptoms were aggravated. Follow-up MRI visualized mass re-growth and spinal cord compression due to the mass and AAS. Posterior C1-2 fixation was performed without further decompression. Twelve months after posterior fixation, no symptoms were apparent and follow-up MRI showed complete resolution of the ROP with C1-2 bony fusion. The ROP with C1-2 instability might be completely resolved only C1-2 fusion without decompression. Furthermore, we speculated that osteoarthritis of C1-2 itself causes a partial tear or degradation of the transverse ligament, that induced formation of ROP.

Enhancement of primary neuronal cell proliferation using printing-transferred carbon nanotube sheets.

Artificial nerve guidance conduits (aNGCs) prepared from polymer scaffolds and carbon nanotubes (CNTs) possess unique chemical and physical properties, and have been widely used in preclinical trials to promote neuronal differentiation and growth. However, there have been only a few reports on the clinical applicability of CNT sheets for proliferation of primary neuronal cells due to safety concerns. The present study assesses the ability and potential applicability of multiwalled CNTs (MWNTs) composited with polydimethylsiloxane (PDMS) sheets to promote and enhance the proliferation of primary neuronal cells. In this study, the aqueous MWNT dispersion was filtered, and the PDMS/MWNT sheets were prepared using a simple printing transfer method. Characterization of PDMS/MWNT sheets demonstrated their unique physical properties such as superior mechanical strength and electroconductivity when compared with PDMS sheets. The effect of the PDMS/MWNT sheets on the neural cell proliferation and cytotoxicity was evaluated using MTT and alamar blue assays. Our results indicate the viability and proliferation of primary neuronal cells and Schwann cells in PDMS/MWNT sheets increased over twice when compared with a noncoated dish that is not usual in the primary neuronal cell growth control (p < 0.05). In addition, PDMS/MWNT sheets enhanced the adhesion and viability of the cells compared with poly-l-lysine coated dishes, which are most commonly used for improving cell adherence. Additionally, the PDMS/MWNT sheets exhibited excellent biocompatibility for culturing neuronal and Schwann cells. Overall, all assessments indicate that PDMS/MWNT sheets are ideal candidates for the development of artificial nerve conduits for clinical use following peripheral nerve injury.

Cultures of Schwann-like cells differentiated from adipose-derived stem cells on PDMS/MWNT sheets as a scaffold for peripheral nerve regeneration.

Carbon nanotubes (CNTs) are promising candidates as novel scaffolds for peripheral nerve regeneration. Schwann cells (SCs) are attractive therapeutic targets due to their pivotal role in peripheral nerve regeneration, but primary SCs have limitations for clinical application. However, adipose-derived stem cells (ASCs) may differentiate into Schwann-like cells. The present study assesses the potential applicability of multiwall CNTs (MWNTs) composited with polydimethylsiloxane (PDMS), which were then seeded with differentiated adipose-derived stem cells (dASCs) to promote neuronal differentiation and growth. Aqueous MWNT dispersion was filtered, and the PDMS/MWNT sheets were prepared using a simple printing-transfer method. Characterization of PDMS/MWNT sheets indicated their unique physical properties, such as superior mechanical strength and electroconductivity, compared with bare PDMS sheets. ASCs were differentiated into Schwann-like cells using a mixture of glial growth factors. Dorsal root ganglion (DRG) neurons were co-cultured with SCs and dASCs on PDMS/MWNTs sheets or noncoated dishes. An alamar blue proliferation assay of dASC and SCs showed significantly more dASC and SCs cultured on PDMS/MWNT sheets at 48 h and 72 h than when cultured on noncoated dishes (p < 0.05). Additionally, when DRG were cultured on PDMS/MWNT sheets seeded with dASCs, the proliferation of DRG neurons and the longest neurite outgrowth length per neuron were significantly greater than when DRG were cultured on PDMS/MWNT sheets alone or on noncoated dishes seeded with SCs or dASCs (p < 0.05). Overall, PDMS/MWNT sheets exhibited excellent biocompatibility for culturing Schwann-like cells differentiated from ASCs. Seeding the dASCs on PDMS/MWNT sheets may produce synergistic effects in peripheral nerve regeneration, similarly to SCs.