[Endoscopic resection of type D trigeminal schwannoma through nasal sinus approach].

Objective: To examine the feasibility and surgical approach of removing type D trigeminal schwannoma through nasal cavity and nasal sinus under endoscope. Methods: Eleven patients with trigeminal schwannoma who were treated in the Department of Otorhinolaryngology, Qilu Hospital of Shandong University from December 2014 to August 2021 were analyzed retrospectively in this study. There were 7 males and 4 females, aged (47.5±13.5) years (range: 12 to 64 years). The neoplasm involved the pterygopalatine fossa, infratemporal fossa, ethmoidal sinus, sphenoid sinus, cavernous sinus, and middle cranial fossa. The size of tumors were between 1.6 cm×2.0 cm×2.0 cm and 5.7 cm×6.0 cm×6.0 cm. Under general anesthesia, the tumors were resected through the transpterygoid approach in 4 cases, through the prelacrimal recess approach in 4 cases, through the extended prelacrimal recess approach in 2 cases, and through the endoscopic medial maxillectomy approach in 1 case. The nasal endoscopy and imaging examination were conducted to detect whether neoplasm recurred or not, and the main clinical symptoms during follow-up. Results: All the surgical procedures were performed under endonasal endoscope, including Gross total resection in 10 patients. The tumor of a 12-year-old patient was not resected completely due to huge tumor size and limited operation space. One patient was accompanied by two other schwannomas located in the occipital region and the ipsilateral parotid gland region originating from the zygomatic branch of the facial nerve, both of which were removed concurrently. After tumor resection, the dura mater of middle cranial fossa was directly exposed in the nasal sinus in 2 cases, including 1 case accompanied by cerebrospinal fluid leakage which was reconstructed by a free mucosal flap obtained from the middle turbinate, the other case was packed by the autologous fat to protect the dura mater. The operation time was (M(IQR)) 180 (160) minutes (range: 120 to 485 minutes). No complications and deaths were observed. No recurrence was observed in the 10 patients with total tumor resection during a 58 (68) months' (range: 10 to 90 months) follow-up. No obvious change was observed in the facial appearance of all patients during the follow-up. Conclusion: Type D trigeminal schwannoma involving pterygopalatine fossa and infratemporal fossa can be removed safely through purely endoscopic endonasal approach by selecting the appropriate approach according to the size and involvement of the tumor.

[Diagnosis and differentiation diagnosis of primary temporomandibular joint cartilage and giant cell related tumor lesions].

Cartilage and giant cell-related neoplastic lesions originating in the temporomandibular joint region have similar clinical, imaging and pathological manifestations, making the diagnosis of these disorders challenging to varying degrees. Diagnostic findings can influence treatment procedures and a definitive pathological diagnosis is important for the prognosis of these conditions. In this article, we discuss the pathological diagnosis and differentiation of four benign cartilage and giant cell related tumors and tumor-like lesions that occur in the temporomandibular joint, namely synovial chondromatosis, tumoral calcium pyrophosphate deposition disease, pigmented villonodular synovitis and chondroblastoma, taking into account their clinical features and histological manifestations, with a view to providing a basis for clinical management.

[Application of biological factor in cementum regeneration].

At the present day, curettage and periodontal surgery comprise the main strategy for the treatment of periodontitis, however, these methods are limited in regenerating cementum. It has been found that some biological factors such asenamel matrix derivative (EMD), transforming growth factor-ß (TGF-ß) and insulin-like growth factor (IGF) could promote cementum regeneration. In the cementum regenerationstudies, there has been a lack of criteria to distinguish cementum from alveolar bone and other types of cementum. Therefore, this article will briefly review the biological factors that affect the cementum regeneration and the molecular markers used to judge the regenerating cementum.

Reemergence of high-Tc superconductivity in the (Li1-xFe x )OHFe1-ySe under high pressure.

In order to elucidate pressure-induced second superconducting phase (SC-II) in A x Fe2-ySe2 (A = K, Rb, Cs, and Tl) having an intrinsic phase separation, we perform a detailed high-pressure magnetotransport study on the isoelectronic, phase-pure (Li1-xFe x )OHFe1-ySe single crystals. Here we show that its ambient-pressure superconducting phase (SC-I) with a critical temperature Tc ≈ 40 K is suppressed gradually to below 2 K and an SC-II phase emerges above Pc ≈ 5 GPa with Tc increasing progressively to above 50 K up to 12.5 GPa. Our high-precision resistivity data uncover a sharp transition of the normal state from Fermi liquid for SC-I to non-Fermi liquid for SC-II phase. In addition, the reemergence of high-Tc SC-II is found to accompany with a concurrent enhancement of electron carrier density. Without structural transition below 10 GPa, the observed SC-II with enhanced carrier density should be ascribed to an electronic origin presumably associated with pressure-induced Fermi surface reconstruction.

The classification of posterior petrous meningiomas and its clinical significance.

This retrospective analysis of the clinical records of 42 patients was used to study the clinical significance of a classification system for posterior petrous meningiomas. According to clinical manifestations and radiological images, posterior petrous meningiomas were classified into three types: type I (cerebella type; 12 patients), tumours involved and compressed the cerebellum; type II (cranial nerve type; 16 patients), tumours involved the cranial nerves; and type III (combined type; 14 patients), tumours involved more than one structure such as the cerebellum, cranial nerves and the brain stem. All patients underwent microneurosurgery and the total resection rate was 90%. It was more difficult totally to resect type II and III tumours than type I tumours and the post-operative functional outcomes were worse. Microneurosurgical techniques and skills are critical to increase the total resection rate of posterior petrous meningiomas in order to decrease the mortality and disability rates.