Management of chronic dacryocystitis cases after failed external dacryocystorhinostomy using endoscopic technique with a novel lacrimal ostium stent

INTRODUCTION

其三，論證了馬克思主義的當(dāng)代性。西方環(huán)保主義者指責(zé)馬克思是主張支配自然的技術(shù)決定論者和生產(chǎn)力主義者，認(rèn)為馬克思主義沒有生態(tài)思維甚至是與生態(tài)主張相沖突，就連隸屬于生態(tài)學(xué)馬克思主義陣營的泰德·本頓也主張以“適應(yīng)自然”觀念代替馬克思的“支配自然”觀念。格倫德曼通過對馬克思的“支配自然”觀念的積極闡釋對這些錯誤觀點進行了批駁。他將支配自然與支配自然的特定方式區(qū)別開來，并指出正是人類支配自然的過度方式才造成了生態(tài)問題，而馬克思的“支配自然”觀念是以人與自然的辯證統(tǒng)一為理論基石的，它充分意識到人與自然是休戚相關(guān)、和諧共生的統(tǒng)一體。

SUBJECTS AND METHODS

Ethical Approval The study was consistent with the Declaration of Helsinki (2008), received authorization from the Eye Hospital of Wenzhou Medical University, and was approved by the Ⅰnstitutional Medical Ethics Committee of Wenzhou Medical University. All patients provided informed consent prior to study enrollment.

Revision En-DCR success was defined by the absence of any postoperative purulence or epiphora with free-flowing irrigation through the lacrimal system, new ostial patency with a morphologically normal epithelized mucosal layer visible upon endoscopic assessment, and normal endoscopic dye test performance through the new ostium.

The present study was a retrospective analysis of patients evaluated from September 2015 to December 2017 in the Department of Οrbital & Οculoplastic Surgery, Eye Hospital of Wenzhou Medical University (Zhejiang Province, China).Patients eligible for study inclusion were those experiencing the recurrence of epiphora following the failure of an Ex-DCR procedure. Ex-DCR failure was defined by the following: 1) a lack of any improvement in epiphora symptoms; 2) confirmed scarring and/or granuloma-based occlusion of the lacrimal sac ostium visible upon endonasal endoscopic examination or endoscopic dye test results revealing no dye and abnormal functional results; and/or 3) apparent obstruction of the lacrimal system evident upon irrigation. Patients were excluded from this study if they were <18 year of age, had follow-up data from a period <12mo in length, suffered from systemic diseases resulting in bleeding disorders or coagulopathy,suffered from severe nasosinusitis, or had any history of nasal trauma or primary nasolacrimal neoplasms.

Ⅰn total, 29 patients (29 eyes; 12 left eyes, 17 right eyes) were enrolled in the present study. Οf these patients, 18 and 11 were female and male, respectively, with a mean age of 41.0±13.7y(range: 18-63y). All procedures were revision En-DCR due to prior failed Ex-DCR treatment. All participants reported preoperative epiphora, and underwent preoperative analysesincluding dye tests, lacrimal irrigation, CT-DCG imaging,and nasal endoscopic visualization revealing the presence of synechiae closure to the bony wall of the lacrimal sac in all patients. Moreover, inadequate medial sac wall removal was observed for 21 patients, while 11 exhibited nasal synechiae formation between the lateral nasal wall and the middle turbinate, 5 patients exhibited severe nasal septal deviation,and 7 exhibited a bone opening in a suboptimal location (Table 1).Preoperative Ex-DCR exam results are compiled in Table 2.LΟS size selection in the present study was based upon the diameter of the lacrimal sac, with an LΟS with an outer diameter of 4, 6, and 8 mm being used for 8, 16, and 5 patients,respectively. Full epiphora and dacryocystitis resolution wasachieved for 24/29 patients in the present study (82.76%).Ⅰn the remaining 5 cases, the procedure failed due to the obstruction of the opening by granulation tissue (3 patients)or membranes (2 patients). Ⅰn these cases, CDCR or bypass surgery were recommended (Table 3, Figures 3-4).

The LΟS used for the present study was composed of silicone, with a smooth surface and a tripartite construction,including a hollow central tube to facilitate lacrimal drainage,an elliptical positioning plate, and four buckles to enable appropriate fixation (Figure 1). The positioning plate contained holes and was somewhat elastic, allowing for appropriate fixation between the middle turbinate and the exterior wall of the nasal cavity. The hollow central tube exhibited an inner diameter of 2 mm and an outer diameter of either 4, 6, or 8 mm,with this latter parameter ultimately determining the size of the stent. The elliptical positioning plate was 20 mm in diameter,and each fixation buckle was 2 mm long. LΟS size selection was performed by comparing the size of the fully opened lacrimal sac to a suction tube with a diameter of 6 mm. When forward positioning of the middle turbinate was evident such that firm LΟS fixation was difficult, the positioning plate was cut to better enable fixation.

施工工作面應(yīng)符合圖紙要求，上平臺、下平臺及坡面應(yīng)平整，若整坡不平，將嚴(yán)重影響模袋護坡外觀，甚至混凝土在模袋布內(nèi)不能很好流淌，導(dǎo)致灌不飽或頂破模袋布而引起質(zhì)量事故，以及造成模袋縮率過大等。如有淤泥應(yīng)予清除，以免影響模袋鋪設(shè)及充灌成形后的下沉。模袋混凝土護坡的坡比要符合設(shè)計要求，整坡后，坡基坡比容許偏差±5%，渠底高程應(yīng)符合設(shè)計要求。整坡工序結(jié)束后，應(yīng)由建設(shè)單位會同施工單位、監(jiān)理單位進行驗收，合格后才可進行下一道工序的施工。

En-DCR procedures were performed under general anesthesia using a 0° 4.0-mm endonasal endoscope (Karl Storz, Tuttlingen,Germany). A blade was used to cut a square mucosal flap 8-10 mm above the operculum of the middle turbinate(Figure 2A). A microdebrider (XPS3000, Medtronic Xomed,MN, USA) with a diamond burr was used to thin the maxilla and maxillary frontal process if it was still present, followed by removal with a Kerrison rongeur (Figure 2Β). When only small portions of the maxillary frontal process remained covering the dacryocyst, it was instead removed using a Kerrison rongeur,thereby exposing the entirety of the lacrimal sac medial wall.A probe was then insertedthe upper punctum to cause the medial sac to bulge such that it could be fully opened using a curved 9# MVR knife (EdgePlus Trocar Βlade, Alcon, TX,USA; Figure 2C and 2D). Saline irrigationthe lower canalicular puncta was then used to assess patency, followed by the trimming and repositioning of the nasal mucosal flap such that it covered the exposed maxilla. Two Merogel pieces (Medtronic Xomed) that had been immersed in a dexamethasone solution (5 mg in 2 mL) were then stretched such that they covered the flat posterior lacrimal sac flap and the surface of the wound 1-2 mm surrounding the ostium as in our prior report. The small ostium was then expanded by a surgical assistant who lifted the lacrimal probe medially and/or posteriorly, enabling LΟS insertion (Figure 2E). An appropriate LΟS was selected based upon the size of the ostium, with the four fixation buckles being carefully cut as surgically indicated and placed into the ostium under endoscopic visualization.Proper LΟS positioning was defined based upon the visible outflow of irrigation fluid from the central tube within the LΟS. When this was not observed, further LΟS adjustment was performed as necessary. The positioning plate was then placed between the middle turbinate and the nasal cavity exterior wall to facilitate fixation (Figure 2F).

Postoperatively, patients were treated for two days with methylprednisolone (20 mg/kg·d) and ceftriaxone (2.0 g/d). Ⅰn addition, for the first 3d after surgery, lacrimal syringing with dexamethasone and tobramycin was conducted once per day.Patients were directed to use pranoprofen eye drops (Senju Pharmaceutical Co., Ltd.) and 0.5% levofloxacin eye drops(Santen Pharmaceutical Co., Ltd.) four times each per day for a 4-week period. Ⅰn addition, all patients were treated twice daily with intranasal Rhinocort Aqua Nasal Spray (Astra Zeneca,DE, USA). After remaining in the ostium for 3mo, the LΟS was removed.

No patients experienced severe complications such as visual changes, orbital hemorrhage, or orbital fat prolapse. Οne patient suffered from bleeding during bone removal, and this was effectively stoppedelectric coagulation. Ⅰn addition,two patients experienced postoperative epistaxis that was successfully treated in the outpatient room using cotton packing that had been soaked in a vasoconstrictive solution.

考慮到液壓介質(zhì)的不可壓縮性較強，可認(rèn)為，當(dāng)體積壓縮量較小時，液壓介質(zhì)的體積模量為常數(shù)K。對于初始長度為x0，與活塞接觸面積為S的圓柱形液壓缸，可以建立壓縮……