Synthesizing Results From Empirical Research on Computer-Based Scaffolding in STEM Education: A Meta-Analysis.

Computer-based scaffolding assists students as they generate solutions to complex problems, goals, or tasks, helping increase and integrate their higher order skills in the process. However, despite decades of research on scaffolding in STEM (science, technology, engineering, and mathematics) education, no existing comprehensive meta-analysis has synthesized the results of these studies. This review addresses that need by synthesizing the results of 144 experimental studies (333 outcomes) on the effects of computer-based scaffolding designed to assist the full range of STEM learners (primary through adult education) as they navigated ill-structured, problem-centered curricula. Results of our random effect meta-analysis (a) indicate that computer-based scaffolding showed a consistently positive (g = 0.46) effect on cognitive outcomes across various contexts of use, scaffolding characteristics, and levels of assessment and (b) shed light on many scaffolding debates, including the roles of customization (i.e., fading and adding) and context-specific support. Specifically, scaffolding's influence on cognitive outcomes did not vary on the basis of context-specificity, presence or absence of scaffolding change, and logic by which scaffolding change is implemented. Scaffolding's influence was greatest when measured at the principles level and among adult learners. Still scaffolding's effect was substantial and significantly greater than zero across all age groups and assessment levels. These results suggest that scaffolding is a highly effective intervention across levels of different characteristics and can largely be designed in many different ways while still being highly effective.

A Bayesian Network Meta-Analysis to Synthesize the Influence of Contexts of Scaffolding Use on Cognitive Outcomes in STEM Education.

Computer-based scaffolding provides temporary support that enables students to participate in and become more proficient at complex skills like problem solving, argumentation, and evaluation. While meta-analyses have addressed between-subject differences on cognitive outcomes resulting from scaffolding, none has addressed within-subject gains. This leaves much quantitative scaffolding literature not covered by existing meta-analyses. To address this gap, this study used Bayesian network meta-analysis to synthesize within-subjects (pre-post) differences resulting from scaffolding in 56 studies. We generated the posterior distribution using 20,000 Markov Chain Monte Carlo samples. Scaffolding has a consistently strong effect across student populations, STEM (science, technology, engineering, and mathematics) disciplines, and assessment levels, and a strong effect when used with most problem-centered instructional models (exception: inquiry-based learning and modeling visualization) and educational levels (exception: secondary education). Results also indicate some promising areas for future scaffolding research, including scaffolding among students with learning disabilities, for whom the effect size was particularly large (g = 3.13).

Evaluation of lacrimal tear drainage mechanism using dynamic fluoroscopic dacryocystography.

PURPOSE: To evaluate the dynamic change of the canaliculus and the lacrimal sac during blinking using fluoroscopic dacryocystography. METHODS: Sixteen patients presenting with unilateral epiphora were enrolled in the study. Fluoroscopic dacryocystography was performed in both eyes, and sequential images of the lacrimal drainage system were acquired during blinking. On examination of the contralateral asymptomatic side, the length of the lower canaliculus and the width of the superior and inferior portions of the lacrimal sac were measured and compared between eyelid closure and opening. RESULTS: The length of the lower canaliculus decreased with eyelid closure in 13 of 16 patients, and the change was statistically significant (p = 0.006, Wilcoxon signed rank test). The width of the superior portion of the lacrimal sac increased with eyelid closure (p = 0.033), but the width of the inferior part did not change significantly (p = 0.679). CONCLUSIONS: With eyelid closure, the canalicular system contracts, and the superior portion of the lacrimal sac dilates; these may be important parts of the active lacrimal pump mechanism. These findings suggested that the canalicular system and the superior portion of the lacrimal sac play key roles in active tear drainage pump.

The effect of autologous serum eye drops on the conjunctivalization over exposed porous polyethylene orbital implant (Medpor(®)) in the rabbit model.

PURPOSE: To assess the efficacy of autologous serum eye drops (AS) in enhancing conjunctivalization over a scleral patch graft on exposed porous polyethylene orbital implant (Medpor(®)). METHODS: Eighteen rabbits were underwent evisceration, implantation of Medpor(®) and homologous scleral patch graft. The conjunctival edge was sutured leaving 5 mm-diameter circular defect. In group A, 20% AS were applied 8 times a day and only balanced salt solution was applied in group B. Digital anterior segment photography was obtained 1, 3, 7, 10, 14, and 21 days after surgery and analyzed with Image Pro Plus(®) software. RESULTS: In the early postoperative period, the average conjunctival growth rate (mm(2)/day) was faster in group A, but failed to show statistical significance (3.79 vs. 3.03, p = 0.26 in 1~3days, 2.39 vs. 1.80, p = 0.59 in 4- days, 0.03 vs. -0.02, p = 0.94 in 7-10 days, Mann-Whitney test). The complete healing rate was higher (67% vs. 56%, p = 0.5, Fisher's exact test) and the mean elapsed time for complete healing (days) was shorter in group A (17.3 vs. 18.2, p = 0.83, Mann-Whitney test), but did not show a statistically significant difference. CONCLUSION: In a rabbit model, 20% AS did not appear to facilitate the healing of small conjunctival defects of exposed porous orbital implant.

One-snip punctoplasty and canalicular curettage through the punctum: a minimally invasive surgical procedure for primary canaliculitis.

PURPOSE: To evaluate treatment results of canalicular curettage through the punctum after 1-snip punctoplasty for primary canaliculitis. DESIGN: Retrospective, interventional case series. PARTICIPANTS: Thirty patients with primary canaliculitis who were treated at Seoul National University Hospital between February 2005 and January 2008. METHODS: All patients underwent 1-snip punctoplasty and canalicular curettage through the punctum, and granules or concretions were removed. After the procedure, oral and topical antibiotics were used for 3 weeks. Demographic data and clinical presentations of the patients were analyzed. The resolution of symptoms and inflammatory signs and complications were evaluated 3 weeks after the procedure. MAIN OUTCOME MEASURES: Resolution rate of the canaliculitis and complications after the procedure. RESULTS: There was a female predominance in the study group (23:7). Common symptoms of canaliculitis included discharge, tearing, and pus or concretions from the punctum. During the procedure, concretions, granules, or discharges were drained in all patients. In 25 (83.3%) of 30 patients, the symptoms and signs of canaliculitis completely resolved 3 weeks after 1 treatment. Two patients (6.7%) required additional curettage. Symptomatic canalicular strictures developed in 2 patients. CONCLUSIONS: Materials were removed easily from the canaliculus using a 1-snip punctoplasty and curettage through the punctum. This procedure, combined with systemic and topical antibiotic therapy, can be a highly effective treatment for primary canaliculitis.

Frontalis sling operation using silicone rod compared with preserved fascia lata for congenital ptosis a three-year follow-up study.

PURPOSE: To evaluate the 3-year results of frontalis sling operation using a silicone rod compared with preserved fascia lata for congenital ptosis. DESIGN: Retrospective, nonrandomized, comparative, interventional case series. PARTICIPANTS: One hundred twenty-three patients with congenital ptosis. METHODS: The medical records of 123 patients who underwent a frontalis sling operation for congenital ptosis were retrospectively reviewed. Patients were divided into 2 groups according to the sling material used; a preserved fascia lata group (n = 63) and a silicone rod group (n = 60). Cosmetic results and recurrence rates were compared between these 2 groups. The cosmetic results of the frontalis sling operation were assessed as good, fair, or poor based on the habitual upper lid heights and symmetry, and bilateral cases and unilateral cases were compared separately. Recurrence was defined as the conversion of the cosmetic result from good or fair to poor category. MAIN OUTCOME MEASURES: Postoperative cosmetic results and recurrence rate. RESULTS: At the 3- and 6-month follow-ups, the cosmetic results were not significantly different between the 2 groups (P = 0.17 and P = 0.25 for bilateral cases and P = 0.14 and P = 0.35 for unilateral cases, respectively, by Armitage's test of trend in proportions). However, the silicone rod group showed significantly better cosmetic results than the preserved fascia lata group at 1, 2, and 3 years after surgery in both bilateral and unilateral cases (all P < 0.05, by Armitage's test of trend in proportions). At 3 years after surgery, the recurrence rates were 29.2% (7/24 bilateral cases) and 11.1% (3/27 unilateral cases) for the silicone rod group, and 63.2% (12/19 bilateral cases) and 41.4% (12/29 unilateral cases) for the preserved fascia lata group. CONCLUSIONS: Given the limitations of this retrospective study, the frontalis sling operation using a silicone rod showed better cosmetic results and lower recurrence rate compared to the procedure using preserved fascia lata up to 3 years after surgery for congenital ptosis. However, only prospective randomized studies can give a more accurate conclusion in that regard. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Decrease in levator function in the anophthalmic orbit.

BACKGROUND/AIMS: It has been argued that levator function in anophthalmic patients is reduced, but no detailed report on this topic has been issued. This study was undertaken to investigate measured levator function in anophthalmic patients, and to determine how measured values are related to prosthesis size. METHODS: Unilateral anophthalmic patients with no significant ptosis, and no history of trauma or surgery to orbit or eyelid were recruited. Levator function was measured with patients wearing their prosthesis, test prosthesis of different heights, and no prosthesis. RESULTS: Thirty-two patients were recruited. Levator function was found to be lower in anophthalmic orbits (10.43 +/- 1.48 mm) than in contralateral normal orbits (12.74 +/- 1.81 mm). Levator function was lower in anophthalmic orbits with any height or type of prosthesis than in contralateral normal orbits (paired t-test, p < 0.05). In the anophthalmic orbits, the levator functions were highest when patients wore a prosthesis of the proper height, and these functions reduced as the prostheses height reduced (linear regression, p < 0.05). CONCLUSION: Diminished levator function in an anophthalmic orbit doesn't necessarily mean that levator muscle function is abnormal. When levator function is measured in an anophthalmic orbit, the fact that it is often underestimated should be taken into account.

Eyelid mass secondary to injection of calcium hydroxylapatite facial filler.

A 37-year-old woman presented with a 2-month history of fullness and ptosis of the left upper eyelid. Examination revealed a 6-cm x 2-cm mass in the left brow and upper eyelid, and a diffuse mass in the lower eyelid. Marked ptosis of the left upper eyelid and elevation of the left lower eyelid were noted. CT showed masses with a bone-like density in the left eyelid and periorbital soft tissue. A through history revealed that the patient had received calcium hydroxylapatite filler injection for nose augmentation 3 days prior to the development of the eyelid masses. The eyelid masses were excised and pathologically confirmed as calcium hydroxylapatite microspherules surrounded by collagen and histiocytes. Two months after surgery, the eyelid masses and ptosis of the left upper eyelid were completely resolved. To our knowledge, this is the first reported case of eyelid mass after injection of calcium hydroxylapatite facial filler for nose augmentation.

Congenital corneal staphyloma treated by evisceration and primary implant placement: 3 cases.

BACKGROUND: We report 3 cases of congenital corneal staphyloma. METHODS: Two cases were cosmetically treated by evisceration and primary implant insertion and 1 case spontaneously converted to phthisis bulbi. RESULTS: Placement of a cosmetic prosthesis improved the external appearances in the first 2 cases. No complications after operation were noted. The final outcome in the third patient was phthisis bulbi, which occurred spontaneously at 5 years of age in the absence of any surgery. INTERPRETATION: Evisceration with primary implant insertion is an appropriate treatment modality for congenital corneal staphyloma.

Conjunctival epithelial changes induced by cilia in patients with epiblepharon or entropion.

PURPOSE: To evaluate the effect of mechanical trauma induced by cilia on the conjunctival epithelium in patients with epiblepharon or entropion and to evaluate changes in epithelium after surgical correction in patients with entropion. DESIGN: Case-control study. METHODS: One hundred and seven eyes of 61 patients were enrolled in this study and were divided into three groups: the epiblepharon group (n = 59), the entropion group (n = 17), and the age-matched control group for the epiblepharon group (n = 31). Impression cytologic specimens were obtained from nasal and temporal bulbar conjunctiva of the epiblepharon and control groups immediately after the induction of general anesthesia. In the entropion group, these were obtained before and one month after surgical correction. Conjunctival changes were graded using the Tseng method and goblet cell densities were compared. RESULTS: Cytologic scores were significantly higher in the epiblepharon group than in the control group (P < .001), and goblet cell densities of nasal and temporal conjunctiva were significantly lower in the epiblepharon group than in the control group (P = .044 and P = .018, respectively). In the entropion group, postoperative scores were significantly lower than preoperative scores in both conjunctival areas (P = .033 and P = .003, respectively). No statistically significant difference was found between nasal and temporal conjunctiva in the three groups. CONCLUSIONS: The persistent mechanical trauma by cilia in patients with epiblepharon or entropion can induce squamous metaplasia of the conjunctival epithelium. However, these conjunctival changes can be reversed by surgical correction.

Lacrimal silicone intubation for anatomically successful but functionally failed external dacryocystorhinostomy.

PURPOSE: To investigate the efficacy of lacrimal silicone intubation for the management of epiphora in patients who have previously undergone anatomically successful dacryocystorhinostomy (DCR). METHODS: The authors recruited 13 patients (4 male, 9 female) who had persistent epiphora after an anatomically successful primary external DCR and conducted lacrimal silicone intubation through the dacryocystorhinostomy site. RESULTS: Mean patient age was 54.2 years (range 42-80) and mean follow-up was 13.8 months (range 6-30). Epiphora was resolved in all 13 patients following silicone intubation. Spontaneous tube extrusion occurred in three patients, but a new one was easily reintubated. CONCLUSIONS: Lacrimal silicone intubation is a simple safe and effective procedure for patients with epiphora even after anatomically successful DCR.

Steatocystoma simplex of the caruncle.

CASE REPORT: The authors present a rare case of steatocystoma simplex occuring in the caruncle. A 42-year-old male presented with an asymptomatic, yellow soft mass in the medial canthal area of the left eye. An excisional biopsy was performed, and the mass lesion was diagnosed as steatocystoma by histological examination. COMMENTS: Steatocystoma simplex should be considered one of the differential diagnoses for patients with an asymptomatic mass lesion in the caruncle.

A phacovitrectomy with a clear corneal incision for a full-thickness macular hole.

PURPOSE: To describe the results of a pars plana vitrectomy, combined with phacoemulsification, using a sutureless, superotemporal, clear corneal incision for patients with a macular hole. METHODS: This study reviewed the records of 22 patients (22 eyes) who underwent a phacoemulsification with the insertion of an acrylic intraocular lens, using a 3.2 mm superotemporal clear corneal incision and a pars plana vitrectomy with an internal limiting membrane peeling in one session, for the treatment of a macular hole. RESULTS: All 22 patients had their macular holes closed using the combined surgical procedures. The mean preoperative visual acuity was 0.086, and the mean postoperative visual acuity was 0.173. This improvement was statistically significant (paired Student's t-test, p < 0.05). No patients developed posterior capsular opacity, retinal detachment, or a cystoid macular edema. The surgically induced astigmatism (SIA) was 0.808 diopters (0.808 +/- 0.761) two months after surgery. CONCLUSIONS: Combining cataract surgery with vitrectomy can achieve visual rehabilitation in the early postoperative period without requiring post-vitrectomy cataract surgery. A sutureless clear corneal incision, used in this procedure, can minimize the SIA and promote postoperative wound healing. If sutureless, transconjunctival, pars plana vitrectomy can be used more widely in the future, then the simplified, combined cataract surgery using a small clear corneal incision will also become more common, hence decreasing operation time, and hastening postoperative recovery.

The survival of freely grafted orbital fat on porous polyethylene orbital implants in the rabbit.

PURPOSE: To investigate the long term survival of orbital fat grafted on a Medpor implant as a method of preventing porous polyethylene orbital implant (Medpor) exposure in anophthalmic sockets. METHODS: In one orbit in each of 8 rabbits, a small amount of retrobulbar orbital fat was grafted between the anterior surface of the Medpor implant and overlying conjunctiva, during the enucleation and Medpor implantation procedure. Two rabbits were sacrificed at 2, 4, 8 and 12 weeks postoperatively and grafted orbital fats were examined by light microscopy. RESULTS: Grafted orbital fat was well-maintained at 2 and 4 weeks, postoperatively. However, fat amounts were significantly reduced at 8 weeks, and viable fat was barely visible at 12 weeks. CONCLUSIONS: In rabbits, orbital fat grafted on Medpor implants was gradually resorbed, and the fat-occupied volume was not maintained.

Effect of basic fibroblast growth factor on fibrovascular ingrowth into porous polyethylene anophthalmic socket implants.

To investigate the effect of basic Fibroblast Growth Factor (bFGF) on fibrovascular ingrowth into porous polyethylene orbital implants (Medpor) and to investigate any differences according to the method of administration. For the treated groups, after evisceration and Medpor implantation, bFGF was administered by soaking Medpor in the bFGF solution, and/or by injecting bFGF into the Medpor 1 week after the operation. Implants were removed 4 weeks after the operation and examined for the degrees of fibrovascular ingrowth by light microscopy. The percentages of the cross-sectional area of the implant occupied by fibrovascular ingrowth and the numbers of proliferated vessels were significantly higher in the bFGF-treated groups (Mann Whitney test, p<0.05). Administration routes had no effect on the degree of fibrovascular ingrowth (Kruskal-Wallis test, p>0.05). bFGF promoted fibrovascular ingrowth into porous polyethylene orbital implants regardless of the route of administration. Therefore, bFGF might be helpful to prevent complications such as implant exposure.

Effect of an acrylic posterior chamber intraocular lens on posterior capsule opacification in cataract patients with associated risk factors.

PURPOSE: To evaluate the effect of an acrylic foldable posterior chamber intraocular lens (PC IOL) on the rate of posterior capsule opacification (PCO) in patients with associated risk factors. SETTING: Department of Ophthalmology, Seoul National University, Seoul, Korea. METHODS: The medical records of 570 patients who had phacoemulsification and foldable PC IOL implantation by the same surgeon from January 1, 1998, to December 31, 1999, were reviewed. Patients with risk factors for PCO (ie, young age, diabetes mellitus) received an acrylic PC IOL to decrease the opacification rate. Their rate was compared to that in patients without associated risk factors who received a foldable silicone PC IOL. RESULTS: In the patients without diabetes mellitus, the PCO rate in patients younger than 60 years with an acrylic PC IOL and in patients older than 60 years with a silicone PC IOL were similar. In patients older than 60 years, the rate of PCO was significantly lower in patients with diabetes mellitus and an acrylic PC IOL than in patients without diabetes mellitus with a silicone foldable PC IOL. CONCLUSIONS: The rate of PCO in patients with risk factors for PCO with an acrylic PC IOL was similar to or lower than that in patients without risk factors with a foldable silicone PC IOL. Therefore, acrylic PC IOLs are preferable, particularly in patients with risk factors for PCO.

Long-term effect of plasmin on the vitreolysis in rabbit eyes.

The aim was to investigate the proteolytic activity of plasmin and its long-term complications. Plasmin was injected into the vitreous cavity of rabbits' eyes. Slit lamp biomicroscopy and electroretinography were performed. Rabbits were serially sacrificed at four months, and globes fixated and prepared for light and transmission electron microscopy. In both the plasmin-injected and control eyes, electroretinography showed a transient decrease in the amplitude, but this recovered to the baseline level in a week. Under the light microscope, the plasmin-treated eyes had a smooth retinal surface, implying separation of the vitreous cortex from the retina. In the control eyes, the collagen fibers remained on the retinal surface. By transmission electron microscopy, the plasmin-treated eyes showed a vitreous-free retinal surface, but no vitreoretinal separation was observed in the control eyes. Plasmin induces a cleavage between the vitreous and the internal limiting membrane, with no long-term complications, so may be a useful pharmacologic adjunct to vitrectomy.

A case of diffuse alveolar hemorrhage after tonsillectomy -A case report-.

Diffuse alveolar hemorrhage (DAH) is an acute, life-threatening event. The blood-gas barrier must be very thin to allow gas exchange and is therefore subjected to high mechanical stresses when the capillary pressure rises. In general anesthesia, inhaled gases cause high mechanical stresses, and thus DAH occurs under certain conditions. We describe a case of inferred postoperative DAH. A 25-year-old man had an acute episode after undergoing a tonsillectomy for snoring. During surgery, no problems occurred and no marked bleeding was observed. After removal of the endotracheal tube, however, the patient had severe cough and hemoptysis. The patient was treated with an antihemorrhagic agent and antibiotics. He recovered after 1 week. Chronic snoring likely caused the alveolar damage in this patient and intubation led to DAH. The patient presented with a benign course that regressed spontaneously with medical intervention.

Dermis-fat graft for treatment of exposed porous polyethylene implants in pediatric postenucleation retinoblastoma patients.

PURPOSE: To demonstrate the use of the autogenous dermis-fat graft for the treatment of porous polyethylene implant exposure and volume augmentation in postenucleation retinoblastoma children. DESIGN: Retrospective, interventional case series. METHODS: Ten children who received a dermis-fat graft at Seoul National University Hospital between July 1, 2005 and January 31, 2010 were included in this study. The patients had undergone unilateral enucleation for retinoblastoma, and received a subconjunctival dermis-fat graft to repair implant exposure and simultaneously correct enophthalmos. The clinical characteristics of the patients, rate of graft survival, and complications were analyzed. The cosmetic outcome was assessed using a grading system. RESULTS: All patients had enucleation using porous polyethylene implant as a primary orbital implant. The average time to exposure was 89.1 ± 22.4 months and the median size of defect was 2 × 3 mm. With a mean follow-up of 28 months, 9 of 10 patients showed well-survived graft without re-exposure. One patient who experienced a graft failure managed with implant rotation and a scleral graft. Seven patients showed significant improvement of enophthalmos. CONCLUSIONS: Implantation of an autogenous dermis-fat graft is a procedure that can be effectively used to treat porous polyethylene implant exposure and simultaneously correct enophthalmos. Use of this procedure can be particularly advantageous for pediatric postenucleation patients.