Drug-Modified Contact Lenses-Properties, Release Kinetics, and Stability of Active Substances with Particular Emphasis on Cyclosporine A: A Review.

The following review focuses on the manufacturing and parameterizing of ocular drug delivery systems (DDS) using polymeric materials to create soft contact lenses. It discusses the types of drugs embedded into contact lenses, the various polymeric materials used in their production, methods for assessing the mechanical properties of polymers, and techniques for studying drug release kinetics. The article also explores strategies for investigating the stability of active substances released from contact lenses. It specifically emphasizes the production of soft contact lenses modified with Cyclosporine A (CyA) for the topical treatment of specific ocular conditions. The review pays attention to methods for monitoring the stability of Cyclosporine A within the discussed DDS, as well as investigating the influence of polymer matrix type on the stability and release of CyA.

Long-term outcomes of StopLoss™ Jones tube (SLJT) and minimally invasive conjunctivodacryocystorhinostomy.

PURPOSE: To assess the long-term outcomes of minimally invasive conjunctivodacryocystorhinostomy (MICDCR) with StopLoss™ Jones tubes. METHODS: A retrospective interventional case series was performed on all patients who underwent a MICDCR with StopLoss™ Jones tubes (SLJT) over a period of 5 years. Patients were followed for a minimum of 1 year after surgery. The parameters studied include patient demographics, clinical presentation, indication for MICDCR, duration of surgery, SLJT length, standard Jones tube drainage classification, complications, and anatomical and functional successes. The variables influencing the outcomes were assessed. Anatomical success was defined as patent SLJT on irrigation, and functional success was defined as resolution of epiphora. Statistical analysis was performed using the R 4.0.4 (R Project, R Foundation). RESULTS: A total number of 44 eyes of 42 patients were studied. The mean age of patients was 61.81 years. Approximately 87% and 64% of the patients completed 2 years and 3 years of follow-up, respectively. The Jones tube drainage class dipped significantly from class I to others at the 3-month follow-up. Classes III and IV dominated the follow-up period between 3 and 18 months, and class II dominated at 24 months and beyond. The anatomical and functional successes at the end of 1-year follow-up were 77.2%. The success was not affected by age, gender, length of SLJT tube, or duration of the surgery. However, the middle turbinate reduction influenced the success (P < 0.03). The common complications noted were tube occlusions (40.9%, 18/44) and inferior tube migration (38.6%, 17/44). CONCLUSION: The long-term outcomes with SLJT were good, but the inferior migration was a significant complication. The results of this study reflect the need for continuity of care as long as the tube is in situ.

Long-Term Quality of Life in Patients Following Minimally Invasive Conjunctivodacryocystorhinostomy With StopLoss Jones Tube.

PURPOSE: To assess the long-term quality of life outcomes of minimally invasive conjunctivodacryocystorhinostomy with StopLoss Jones tubes. METHODS: A retrospective interventional case series was performed on all patients diagnosed with proximal bicanalicular obstruction who underwent a minimally invasive conjunctivodacryocystorhinostomy with StopLoss Jones tubes over a period of 5 years from October 2014 to September 2019. The procedure was performed as per standard published protocols of minimally invasive conjunctivodacryocystorhinostomy and StopLoss Jones tubes. Patients were followed for a minimum of 1 year after surgery. The tools employed to study were the "Jones tube satisfaction questionnaire" and the "Nasolacrimal duct obstruction-symptom score." These tools were employed at every step from the preoperative stage to each of the follow ups. Statistical analysis was performed using the R 4.0.4 (R Project, R Foundation). RESULTS: A total number of 44 eyes of 42 patients were studied. Of these, 73.81% (31/42) were females. The mean age of patients was 61.81 years. Approximately 87% and 64% of the patients completed 2 and 3 years of follow up, respectively. For up to 2 months postoperative period, the outcomes were excellent, with the majority (76.74%, 33/43) reporting "moderately satisfied" outcomes on Jones tube satisfaction questionnaire. The dissatisfaction began at the 3-month follow up (4.55%, 3/44) and peaked at 6-month follow up (25%, 11/44), owing to tube-related complications. The mean ± standard deviation nasolacrimal duct obstruction-symptom score scores dipped from 19.98 ± 2.88 at baseline to 5.58 ± 2.99 at the 2-month follow up. Similar to Jones tube satisfaction questionnaire, the scores began worsening at 3-month follow up (9.8 ± 5.86) with the poorest scores at 6 months (12.34 ± 5.96), and these changes were significant as compared with the baseline (p < 0.001). The Jones tube satisfaction questionnaire and the nasolacrimal duct obstruction-symptom score scores showed significant improvements at 1-year follow up, owing to appropriate management of complications. The good outcomes were maintained for up to 3 years of postoperative period. CONCLUSIONS: The long-term quality of life outcome following minimally invasive conjunctivodacryocystorhinostomy with StopLoss Jones tubes was good. The quality of life significantly suffers between 3 and 6 months following the surgery and improves equally well following appropriate management of complications.

Lacrimal Sac Reconstruction Using a Nasal Mucosal Graft.

Iatrogenic lacrimal drainage trauma during surgery is not common. It has been reported during orbital surgeries, medial maxillectomies, post-trauma repairs, excision of adherent lesions in the vicinity, and facial reconstructive procedures. The present case reports a focal loss of the lacrimal sac wall during the excision of an intricate dermoid cyst. The defect was sealed by a nasal mucosal graft harvested from the floor of the ipsilateral nasal cavity. Postoperatively, the epiphora was resolved, and a CT-dacryocystography confirmed the anatomical integrity of the reconstructed lacrimal sac.

A Structural Potential of Rare Trinucleotide Repeat Tracts in RNA.

Among types of trinucleotide repeats, there is some disproportion in the frequency of their occurrence in the human exome. This research presents new data describing the folding and thermodynamic stability of short, tandem RNA repeats of 23 types, focusing on the rare, yet poorly analyzed ones. UV-melting experiments included the presence of PEG or potassium and magnesium ions to determine their effect on the stability of RNA repeats structures. Rare repeats predominantly stayed single-stranded but had the potential for base pairing with other partially complementary repeat tracts. A coexistence of suitably complementary repeat types in a single RNA creates opportunities for interaction in the context of the secondary structure of RNA. We searched the human transcriptome for model RNAs in which different, particularly rare trinucleotide repeats coexist and selected the GABRA4 and CHIC1 RNAs to study intramolecular interactions between the repeat tracts that they contain. In vitro secondary structure probing results showed that the UAA and UUG repeat tracts, present in GABRA4 3' UTR, form a double helix, which separates one of its structural domains. For the RNA CHIC1 ORF fragment containing four short AGG repeat tracts and the CGU tract, we proved the formation of quadruplexes that blocked reverse transcription.

Long-term outcomes of primary transcanalicular laser dacryocystorhinostomy.

PURPOSE: To assess the long-term outcomes of transcanalicular laser dacryocystorhinostomy in cases of primary acquired nasolacrimal duct obstruction (PANDO). METHODS: Retrospective interventional case series was performed on all patients diagnosed with PANDO and who underwent a primary transcanalicular laser dacryocystorhinostomy from Jan 2014 to June 2016. The procedure was performed using 980 nm diode laser. All the patients additionally underwent intraoperative adjunctive procedures: mitomycin C application and silicone intubation. Patients were followed for up to 3 years after surgery. Anatomical success was defined as patent ostium on irrigation, and functional success was defined as resolution of epiphora. The parameters studied include patient demographics, clinical presentation, type of anesthesia, duration of surgery, laser energy delivered, complications, and anatomical and functional success. The variables influencing the outcomes were assessed. Statistical analysis was performed using the package Statistica (version 10.0, Statsoft, Poland). RESULTS: A total number of 205 patients were assessed. Of these, 73.17% (150/205) were females. The mean age of patients was 62.92 years. The mean laser energy used was 1060.09 J, and the mean operating time was 22.33 min. Approximately, 95% and 68% of the patients completed 1 year and 3 years of follow-up, respectively. The anatomical and functional success rates dropped significantly beyond the 3 months and 6 months postoperative period and maintained the lower success rates beyond 1-year follow-up for up to 3 years. The anatomical and functional success at the end of 3-year follow-up was 56.12% and 33.81%, respectively. The functional success was not affected by gender (P = 0.132), age (P = 0.956), laser energy (P = 0.626), or duration of the surgery (P = 0.906). However, the intraoperative pain scale was influenced by the laser energy (P < 0.001) and the duration of the surgery (P < 0.001). CONCLUSION: The anatomical and functional outcomes of primary transcanalicular laser dacryocystorhinostomy are suboptimal and not encouraging in the long term.

Soft Contact Lenses as Drug Delivery Systems: A Review.

This review describes the role of contact lenses as an innovative drug delivery system in treating eye diseases. Current ophthalmic drug delivery systems are inadequate, particularly eye drops, which allow about 95% of the active substance to be lost through tear drainage. According to the literature, many interdisciplinary studies have been carried out on the ability of contact lenses to increase the penetration of topical therapeutic agents. Contact lenses limit drug loss by releasing the medicine into two layers of tears on either side of the contact lens, eventually extending the time of contact with the ocular surface. Thanks to weighted soft contact lenses, a continuous release of the drug over an extended period is possible. This article reviewed the various techniques to deliver medications through contact lenses, examining their advantages and disadvantages. In addition, the potential of drug delivery systems based on contact lenses has been extensively studied.

The Use of Anterograde Percutaneous Transluminal Coronary Angioplasty Balloons in Congenital Nasolacrimal Duct Obstruction: A Cost-Effective Alternative to the Traditional Dacryoplasty Balloons.

PURPOSE: To assess the efficacy of commonly available coronary angioplasty balloon catheters as a low-cost alternative to the traditional dacryoplasty catheters in select patients of congenital nasolacrimal duct obstruction. METHODS: A prospective, interventional study was performed between July 2018 and December 2018 in children with congenital nasolacrimal duct obstruction, who underwent balloon dacryoplasty using the coronary angioplasty balloon catheters (2.75 × 10 mm, SPALNO, Cardiomac, Haryana, India). The inclusion criteria were children ≥4 years of age, and/or previously failed probing and/or previous failed intubation. Parameters documented were demographics, techniques, costs, complications, and postoperative outcomes. RESULTS: Twenty-three eyes of 22 children underwent balloon dacryoplasty using coronary angioplasty balloon catheters. The mean age of the patients was 4.33 years (range 1.5-10 years). The procedure was performed in 8 patients (8 eyes, 35%) as the primary procedure. The remaining 14 patients (15 eyes, 65%) had a history of probing, of which 4 eyes had it twice earlier. All eyes underwent balloon dacryoplasty as per standard protocols. The insertion profile and trackability of the coronary catheters were good. At a mean follow up of 6.17 months (range 1.5-9 months), anatomical and functional success was obtained in 87% cases (n = 20/23). No lacrimal passage trauma or injuries were noted during the procedure. The cost of coronary balloon catheter was approximately $60. CONCLUSIONS: The present pilot study has shown that outcomes of balloon dacryoplasty in patients with congenital nasolacrimal duct obstruction with coronary balloon catheters is comparable to that of traditional balloons and offers significant economic advantage for developing nations.

Insomnia, postpartum depression and estradiol in women after delivery.

After childbirth, women may develop symptoms of depression with the associated sleep disturbances. This study assessed the relationship between insomnia and both depression symptoms and blood estradiol levels in women during the early postpartum period. 84 patients were assessed 24-48 h after labor. The main assessment methods were the following psychometric scales: Beck Depression Inventory (BDI), Edinburgh Postnatal Depression Scale (EPDS) and Athens Insomnia Scale (AIS). Serum estradiol levels were measured using ELISA assay. Women who developed postpartum insomnia significantly more often reported insomnia during pregnancy (P = 0.001), were more likely to have suffered from depression in the past (P = 0.007) and had significantly higher BDI (P = 0.002) and EPDS (P = 0.048) scores. Our study demonstrated no significant association between Restless Legs Syndrome (RLS) during pregnancy and postpartum insomnia. The groups of women with and without postpartum RLS showed no significant differences in the incidence of postpartum insomnia. No significant differences in estradiol levels were observed in women with and without postpartum insomnia. The study showed the following factors to play a major role in development of postpartum insomnia: an increase in Beck Depression Inventory score, a history of depression and a history of insomnia during pregnancy.

Cell reactions and immune responses to photodynamic therapy in oncology.

Photodynamic therapy (PDT) is a noninvasive, highly selective method for the treatment of diseases characterized by uncontrolled cell proliferation. It was clinically approved more than 30 years ago. PDT involves the selective uptake of a photosensitizer (PS) by neoplastic tissue, which is able to produce reactive oxygen species (ROS) upon irradiation with visible or near-infrared (NIR) light. ROS induce destruction of target cells and damage of tumor-associated vasculature and activate an antitumor immune response, leading to tumor regression. The execution of this process is attained by different mechanisms, including host immune responses and activation of cell death pathways: apoptosis and necrosis.

Repetition suppression and repetition enhancement underlie auditory memory-trace formation in the human brain: an MEG study.

The formation of echoic memory traces has traditionally been inferred from the enhanced responses to its deviations. The mismatch negativity (MMN), an auditory event-related potential (ERP) elicited between 100 and 250ms after sound deviation is an indirect index of regularity encoding that reflects a memory-based comparison process. Recently, repetition positivity (RP) has been described as a candidate ERP correlate of direct memory trace formation. RP consists of repetition suppression and enhancement effects occurring in different auditory components between 50 and 250ms after sound onset. However, the neuronal generators engaged in the encoding of repeated stimulus features have received little interest. This study intends to investigate the neuronal sources underlying the formation and strengthening of new memory traces by employing a roving-standard paradigm, where trains of different frequencies and different lengths are presented randomly. Source generators of repetition enhanced (RE) and suppressed (RS) activity were modeled using magnetoencephalography (MEG) in healthy subjects. Our results show that, in line with RP findings, N1m (~95-150ms) activity is suppressed with stimulus repetition. In addition, we observed the emergence of a sustained field (~230-270ms) that showed RE. Source analysis revealed neuronal generators of RS and RE located in both auditory and non-auditory areas, like the medial parietal cortex and frontal areas. The different timing and location of neural generators involved in RS and RE points to the existence of functionally separated mechanisms devoted to acoustic memory-trace formation in different auditory processing stages of the human brain.

Two sequential processes of change detection in hierarchically ordered areas of the human auditory cortex.

Auditory deviance detection occurs around 150 ms after the onset of a deviant sound. Recent studies in animals and humans have described change-related processes occurring during the first 50 ms after sound onset. However, it still remains an open question whether these early and late processes of deviance detection are organized hierarchically in the human auditory cortex. We applied a beamforming source reconstruction approach in order to estimate brain sources associated with 2 temporally distinct markers of deviance detection. Results showed that rare frequency changes elicit an enhancement of the Nbm component of the middle latency response (MLR) peaking at 43 ms, in addition to the magnetic mismatch negativity (MMNm) peaking at 115 ms. Sources of MMNm, located in the right superior temporal gyrus, were lateral and posterior to the deviance-related MLR activity being generated in the right primary auditory cortex. Source reconstruction analyses revealed that detection of changes in the acoustic environment is a process accomplished in 2 different time ranges, by spatially separated auditory regions. Paralleling animal studies, our findings suggest that primary and secondary areas are involved in successive stages of deviance detection and support the existence of a hierarchical network devoted to auditory change detection.

Surface tension and density of Si-Ge melts.

In this work, the surface tension and density of Si-Ge liquid alloys were determined by the pendant drop method. Over the range of measurements, both properties show a linear temperature dependence and a nonlinear concentration dependence. Indeed, the density decreases with increasing silicon content exhibiting positive deviation from ideality, while the surface tension increases and deviates negatively with respect to the ideal solution model. Taking into account the Si-Ge phase diagram, a simple lens type, the surface tension behavior of the Si-Ge liquid alloys was analyzed in the framework of the Quasi-Chemical Approximation for the Regular Solutions model. The new experimental results were compared with a few data available in the literature, obtained by the containerless method.

The Use of Hand-Held Digital Otoscope as a Basic Nasal Endoscopy Tool for Lacrimal Evaluation and Pedagogy Instrument.

PURPOSE: To investigate the utility of a hand-held digital otoscope for nasal endoscopy and as a pedagogy tool for residents and fellows in patients undergoing external dacryocystorhinostomy (DCR) surgery. METHODS: A digital otoscope (MS450-NTE, Teslong Inc., USA) comprising a digital screen device and a connectible camera probe was used for performing nasal endoscopy. Inspection of nasal cavities was performed pre-, intra-, and post-operatively in sequential patients with nasolacrimal duct obstruction, who underwent DCR or lacrimal probing. Images (1920 × 1080 pixels) and videos (1280 × 720 pixels) were captured. The device was also used for training residents and fellows in performing nasal endoscopy, and to teach basic concepts. RESULTS: The digital otoscope could be used for routine outpatient nasal examination and for performing minor procedures. 53.8% (n = 13) of ophthalmology trainees had never observed nasal endoscopy and 84.6% could not identify more than one major structure correctly prior to the current training. Post-training, all trainees could independently perform nasal endoscopy with the device and 76.9% identified all structures correctly. CONCLUSION: A digital otoscope with a camera probe is a handy tool for nasal endoscopy and pedagogy. Low-cost gadgets such as this device can effectively be used for performing outpatient nasal endoscopy when expensive endoscopes are unavailable and in peripheral healthcare centers.

Virtual Reality and Mixed Reality-Assisted Endoscopic DCR in Extremely Complex Lacrimal Obstructions.

OBJECTIVE: To report the techniques and outcomes of virtual reality (VR) and mixed reality (MR)-assisted powered endoscopic dacryocystorhinostomy (DCR) in extremely complex lacrimal drainage obstructions. METHODS: A prospective, non-randomized clinical study was performed in complex syndromic congenital nasolacrimal duct obstruction (CNLDO) and post-traumatic secondary acquired lacrimal duct obstruction (SALDO) in the setting of Le Fort fractures. All patients underwent preoperative planning in VR and intraoperative planning with a step ahead with MR assistance during the surgery. Surgery was supported by mixed reality intraoperative guidance with the use of the prearranged 3D models and real-time-rendered digital models. Parameters assessed include demographics, clinical presentation, complexities of the nasolacrimal duct obstruction, preoperative and intraoperative utility of VR and MR models, surgical techniques, complications, and outcomes. RESULTS: The technique is described as a proof of concept in challenging situations with Apert syndrome and traumatic SALDOs with gross malposition of the sac, and gross nasal and lacrimal anatomical deformities. The VR models helped the surgeon to assess the details of the altered anatomy preoperatively to plan an appropriate approach. Intraoperatively, MR models were present in the surgeon's view without disturbing the endoscopic procedure. Intermittently, the surgeon could pull any of the models virtually present in the operating room, slice them, rotate them, and intricately study the alterations in a stepwise manner, as the surgery proceeds. CONCLUSION: Virtual reality and mixed reality-assisted powered endoscopic DCR can be an alternate approach reserved for extremely challenging cases of complex syndromic CNLDOs and post-traumatic SALDOs. LEVEL OF EVIDENCE: Level 4 Laryngoscope, 2024.

Complications of Surgically Assisted Rapid Maxillary/Palatal Expansion (SARME/SARPE)-A Retrospective Analysis of 185 Cases Treated at a Single Center.

Objectives: The study aims to assess and classify complications in patients treated for maxillary transverse deficiency using surgically assisted rapid maxillary/palatal expansion (SARME/SARPE) under general anesthesia. The classification of the complications aimed to assess the difficulty of their treatment as well as estimate its real cost. Methods: The retrospective study covered 185 patients who underwent surgery for a skeletal deformity in the form of maxillary constriction or in which maxillary constriction was one of its components treated by a team of maxillofacial surgeons at one center (97 females and 88 males, aged 15 to 47 years, mean age 26.1 years). Complications were divided into two groups: early complications (up to 3 weeks after surgery) and late complications (>3 weeks after surgery). In relation to the occurrence of complications, we analyzed the demographic characteristics of the group, type of skeletal deformity (class I, II, III), presence of open bite and asymmetry, surgical technique, type and size of appliance used for maxillary expansion, as well as the duration of surgery. Results: In the study group, complications were found in 18 patients (9.73%). Early complications were found in nine patients, while late complications were also found in nine patients. Early complications include no possibility of distraction, palatal mucosa necrosis, perforation of the maxillary alveolar process caused by the distractor and asymmetric distraction. Late complications include maxillary incisor root resorption, no bone formation in the distraction gap, and maxillary incisor necrosis. None of the patients required prolonged hospitalization and only one required reoperation. Conclusions: Complications were found in 18 patients (9.73%). All challenges were classified as minor difficulties since they did not suppress the final outcome of the treatment of skeletal malocclusion. However, the complications that did occur required additional corrective measures. Surgically assisted rapid maxillary expansion, when performed properly and in correlation with the correct orthodontic treatment protocol, is an effective and predictable technique for treating maxillary constriction.

Anti-SARS-CoV-2 Antibodies Level and COVID-19 Vaccine Boosters among Healthcare Workers with the Highest SARS-CoV-2 Infection Risk-Follow Up Study.

During the COVID-19 pandemic, several vaccines were developed to limit the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, due to SARS-CoV-2 mutations and uneven vaccination coverage among populations, a series of COVID-19 waves have been caused by different variants of concern (VOCs). Despite the updated vaccine formulations for the new VOC, the benefits of additional COVID-19 vaccine doses have raised many doubts, even among high-risk groups such as healthcare workers (HCWs). We examined the factors underlying hesitancy to receive COVID-19 booster vaccine doses and analysed the anti-SARS-CoV-2 IgG antibody response after booster vaccination among HCWs. Our study found that 42% of the HCWs were hesitant about the second booster dose, while 7% reported no intent to get vaccinated with any additional doses. As reasons for not vaccinating, participants most frequently highlighted lack of time, negative experiences with previous vaccinations, and immunity conferred by past infections. In addition, we found the lowest post-vaccination antibody titres among HCWs who did not receive any vaccine booster dose and the highest among HCWs vaccinated with two booster doses.

The consequences of the new European reclassification of non-invasive brain stimulation devices and the medical device regulations pose an existential threat to research and treatment: An invited opinion paper.

A significant amount of European basic and clinical neuroscience research includes the use of transcranial magnetic stimulation (TMS) and low intensity transcranial electrical stimulation (tES), mainly transcranial direct current stimulation (tDCS). Two recent changes in the EU regulations, the introduction of the Medical Device Regulation (MDR) (2017/745) and the Annex XVI have caused significant problems and confusions in the brain stimulation field. The negative consequences of the MDR for non-invasive brain stimulation (NIBS) have been largely overlooked and until today, have not been consequently addressed by National Competent Authorities, local ethical committees, politicians and by the scientific communities. In addition, a rushed bureaucratic decision led to seemingly wrong classification of NIBS products without an intended medical purpose into the same risk group III as invasive stimulators. Overregulation is detrimental for any research and for future developments, therefore researchers, clinicians, industry, patient representatives and an ethicist were invited to contribute to this document with the aim of starting a constructive dialogue and enacting positive changes in the regulatory environment.

Experience of the First Three Years of Independent Practice Following Surgical Training: Time Taken and Long-Term Outcomes of Powered Endoscopic Dacryocystorhinostomy.

PURPOSE: To describe the changes in the time taken and the long-term outcomes of powered endoscopic dacryocystorhinostomy (PEnDCR) performed by a freshly trained surgeon in the first three years following the surgical training. METHODS: A retrospective interventional analysis was performed on all patients who underwent a primary or a revision PEnDCR from October 2016 to February 2020. Data obtained include demographics, presentation, previous interventions, pre-operative endoscopy findings, intra-operative findings, post-operative complications, and outcomes. Intra-operative features like the Boezaart surgical field scale, adjunctive endonasal procedures, and time taken for the procedure were noted. A minimum follow-up of 12 months was considered for final analysis. Statistical analysis was performed using software R (v 4.1.2). RESULTS: A total of 159 eyes of 155 patients underwent PEnDCR, of which 141 eyes were primary surgeries. The mean age was 64.28 years, with M:F ratio being 1:2.5. The number of cases performed per year steadily increased after the first year, and so was the case with adjunctive endonasal procedures. The mean procedure time showed an average reduction by 10.80 and 12.81 minutes for surgeries with and without adjunctive endonasal procedures (p < .001). The majority (77.3%, 123/159) of the intra-operative fields were classified as Grade 3 on the Boezaart scale. The practice of post-operative mitomycin C use significantly and steadily reduced over the three years (p < .001). Bleeding and granuloma formation were the common undesirable post-operative findings and showed a significant (p < .001) decline beyond the first year. The anatomical and functional success were (96.18%, 91.72%), (95.71%, 92.14%), and (96.16%, 91.94%), respectively, at 12, 24 and 36 months follow up. CONCLUSION: Several intra-operative and post-operative parameters of PEnDCR patients showed improvement beyond the first year of independent practice. The success rates were well-maintained in the long term.