Application Of Multi-slice Spiral CT Multi-planar Recombination Technique In Nasolacrimal Duct Obstruction

Objective:To evaluate the application value of 64-slice spiral computed tomography(CT)multiplanar recombination technique in nasolacrimal duct obstructive diseases.Method:A total of 168 patients(207eyes)with nasolacrimal duct obstructive disease admitted to the Department of Ophthalmology,Qingdao Municipal Hospital,Third Clinical College,Qingdao University Medical College from July 2015 to June 2018 were selected as NDO group.Among them,112 patients(140 eyes)with simple nasolacrimal duct obstructive disease and 56 patients(67 eyes)with chronic dacryocystitis were treated with catheterization and nasal endoscopic dacryocystorhinostomy.And determine the effect after treatment,which is divided into effective patients and invalid patients.The normal subjects were selected as the control group of 48 patients(96 eyes).All examiners underwent routine examination of the orbital CT examination and covered the corresponding area of the entire lacrimal passage.Patients with chronic dacryocystitis were examined with lacrimal sac angiography.The CT examination uses a X-ray beam to perform a continuous thin-layer axial scan of the examination area,and the obtained data is input into the workstation.The CT multi-planar recombination technique(MPR)is used in cooperation with the imaging doctor to set the reconstruction layer thickness of 0.4 mm to perform the oblique crown position.,sagittal multiplanar reconstruction,using computer measurement tools to measure the relevant values of lacrimal duct structure.The data of the nasolacrimal duct were analyzed in the NDO group and the control group.NDO patients undergoing surgical treatment were analyzed for the correlation between the data of lacrimal passages in patients with effective treatment and those with treatment failure.Result:1.The values of the oblique coronal and dysplastic lengths of the nasolacrimal duct and the upper,middle and lower transverse diameters of the control group were 10.98±1.43 mm,12.49±1.67 mm,4.62±0.69 mm,3.88±0.65 mm,respectively.5.39±0.73 mm,the measured values of the nasolacrimal duct in the NDO group were 11.17±1.65 mm,12.75±1.52 mm,4.57±0.76 mm,3.72±0.52 mm,5.25±0.89 mm,and the NDO group and the control group were bony nose.There was statistical difference between the transverse diameter of the lacrimal duct(t=-2.296,p<0.05),and the middle transverse value of the NDO group was small.There was no statistical difference between the other data.2.Data of simple NDO in patients undergoing catheterization,data analysis of the upper,middle and lower transverse diameters of the nasolacrimal duct in effective and ineffective patients,compared with the transversediameter of the nasolacrimal duct(t=-1.926,p <0.05)There is statistical difference,and the value of the middle transverse traverse is small in the invalid patients;3,chronic dacryocystitis in the upper segment of the nasolacrimal duct obstruction 39 eyes(58.21%),the middle segment obstructed 22 eyes(32.83%),the lower segment blocked 6 eyes;4,Et-DCR treatment of patients with chronic dacryocystitis,effective patient and ineffective patients with lacrimal sac CT coronal approximate area analysis(t =-1.926,p <0.05)was statistically significant,ineffective patients with small lacrimal sac.Conclusion:In this study,CT multi-planar recombination technique was used to measure the data of the nasolacrimal duct,and the lacrimal sac angiography was used to study the lacrimal sac of patients with chronic dacryocystitis.Through analysis,the following conclusions can be obtained:1.Patients with nasolacrimal duct obstructive disease have narrower nasolacrimal ducts than normal people.It can be considered that stenosis of the nasolacrimal duct is a risk factor.2.Through the catheterization treatment of patients with simple nasolacrimal duct obstructive disease ineffective patients with effective osseous nasolacrimal duct transverse narrow,that the bone nasolacrimal duct diameter is one of the reasons that affect the success rate of surgery.3.In patients with chronic dacryocystitis treated with Et-DCR,patients with treatment failure had a smaller area of lacrimal sac than patients with effective treatment and were statistically significant.4.CT-DCG can clearly diagnose the location of lacrimal duct obstruction in patients with chronic dacryocystitis,and have a guiding role in Et-DCR.