Persistent fetal vasculature syndrome (PFVS) is a rare congenital vitreous dysplasia, which is classified as anterior, posterior and combined types according to the location of the vascular abnormalities. The clinical manifestations of PFVS are diverse, and early surgical intervention is very important. The main objective of surgical treatment is to remove the anterior and posterior traction between fibrovascular membranes and retina as well as lens, and to reconstruct clear visual axis. Surgical treatments include pupilloplasty, lensectomy with or without intraocular lens implantation and vitrectomy via limbal or scleral approach. For new technologies, the applications of ophthalmic viscosurgical device and femtosecond lasers have desirable results . In addition to focusing on improving the success rate of surgery, it is also necessary to systematically and comprehensively assess the overall preoperative condition and postoperative visual function of the patients. PFVS eyes have limited improvement in postoperative vision, which is related to the extent of lesion involvement and the occurrence of complications. Eyes with macular dysplasia and tractional retinal detachment, as well as elongated ciliary process, have a poor prognosis of vision after surgery. How to improve postoperative vision in the eye affecting the posterior segment of the eye with PFVS from the microscopic anatomical relationship between the fibrous vascular pedicle and the retina is worth further study. On the other hand, reducing surgical trauma and optimizing surgical procedures in order to improve postoperative visual acuity and reduce postoperative complications are also the key research directions of future PFVS treatments.
ObjectiveTo observe the diagnostic sensitivity and specificity of color Doppler flow imaging (CDFI) for persistent hyperplastic primary vitreous (PHPV). MethodsThe clinical data of 71 children (93 eyes) with congenital cataract which suspected of concurrent PHPV were retrospectively analyzed. The children included 45 males (54 eyes) and 26 females (39 eyes), aged from 1 to 24 months, with an average age of (7.6±4.3) months. All eyes were examined by CDFI, and observe whether there was a pathological strip in the vitreous, the site of the connection between the strip echo and the wall of the eye and the signal of blood flow on the strip echo. Within 1 week after a CDFI examination under general anesthesia, 64 children (79 eyes) underwent lens excision combined with vitrectomy and the other 14 eyes of 7 children underwent mydriatic fundus examination by two experienced eye specialists. Combined with clinical features of PHPV, the diagnosis and differential diagnosis were made according to the clouding of the lens, posterior capsule proliferation, vitreous proliferation and retinal detachment position which were found during operation and fundus examination. Compare and analyze the CDFI examination results and the above diagnosis results, calculate the sensitivity and specificity of CDFI for PHPV. ResultsIn surgery and mydriatic fundus examination results of 93 eyes, vitreous abnormal in 85 eyes, no significant changes were found in vitreous of the other 8 eyes. In 85 eyes of abnormal vitreous, 68 eyes were diagnosed as PHPV, 16 eyes were diagnosed as familial exudative vitreoretinopathy (FEVR), and 1 eye was diagnosed as treactional retinal detachment. In 85 eyes of abnormal vitreous which were found by surgery and fundus examination, CDFI confirmed 81 eyes and its diagnostic sensitivity was 95.3%; the other 4 eyes were not found vitreous abnormality, and the missed diagnosis rate was 4.7%. Surgery and mydriatic fundus examination found no vitreous abnormal in 8 eyes, but CDFI explored strip low echo connected with the optic disc or posterior lens capsule in vitreous. In the 68 eyes of PHPV which were diagnosed by surgery or fundus examination, 59 eyes had the same diagnosis of CDFI, the sensitivity of CDFI was 86.8%; PHPV was not diagnosed in 25 eyes by surgery or fundus examination, but only 8 eyes were also not diagnosed by CDFI, and the specificity of CDFI was 32.0%. The remaining 17 eyes were diagnosed as FEVR in 16 eyes and traction retinal detachment in 1 eye after surgery or mydriatic fundus examination, but they were all diagnosed as PHPV in CDFI. The misdiagnosis rate of CDFI was 68.0%. ConclusionFor PHPV, the diagnostic sensitivity and specificity of CDFI are 86.8% and 32.0%, respectively.
In the process of evidence-based practice, the evaluation of evidence applicability relied on the subjective judgment of clinicians, while the systematic method of which was still in lack. The complex clinical information of traditional Chinese medicine (TCM) enhanced the uncertainty and risk of applying evidence. Based on the analysis of the process of evidence-based practice, this paper introduced the method of TCM evidence applicability evaluation and used the raw data of clinical trials to develop a clinical prediction model to enable the assessment of the evidence applicability on individual patients. The establishment of individual evidence applicability evaluation method could promote the rational application of TCM evidence in the long term.