Post-radiation middle ear effusion in NPC patients: Analysis of patient, tumour, and radiation factors

OBJECTIVE

The purpose of this study was to investigate whether patient, tumour and radiation therapy factors are associated with development of middle ear effusion (MEE) in nasopharyngeal carcinoma (NPC) patients.

DEIGN, SETTINGS, AND PARTICIPANTS

A retrospective review of NPC patients treated between January 2000 and June 2018 at Rabin Medical Center. Patient factors, tumour factors, radiation doses, and radiation fields were collected and outlined if needed (middle ear, eustachian tube [ET], tensor veli palatini [TVP], and levator palatini [LVP] muscles), then analysed and compared between patients with MEE and those without and between sides in patients with unilateral MEE.

MAIN OUTCOME MEASURES AND RESULTS

Seventy-three patients were enrolled. Most were males (71.2%) with advanced-stage diseases (78%). At the time of diagnosis 14 patients (19.2%) presented with MEE. Following radiation, 18 patients, with no evidence of MEE at presentation, developed MEE. Tumour stage, histology, and laterality were not associated with development of MEE. Comparison of mean radiation field dosages including-gross target volume, clinical target volume, and patient target volume showed no association with post-radiation MEE. In addition, no difference was found in the radiation doses to the middle ear, ET or the LVP nor the TVP between ears with and without MEE.

CONCLUSIONS

Post-irradiation MEE remains a common adverse effect in NPC patients. Surprisingly, tumour stage, tumour laterality, and histology were not associated with MEE. Similar findings were observed for total radiation doses and specific doses to the middle ear, ET, and ET muscles.

Simethicone use in drug-induced sleep endoscopy improves visibility

PURPOSE

To assess the effect of simethicone, a defoaming agent, on improving visibility during drug-induced sleep endoscopy (DISE) in obstructive sleep apnea (OSA).

METHODS

The study was a retrospective case-series study on patients with OSA who failed positive airway pressure (PAP) treatment. Patient parameters were recorded including age, BMI, neck and abdominal circumference, and apnea-hypopnea index (AHI). Comparisons were made between DISE procedures performed with and without the administration of simethicone. Visibility during DISE was independently graded by two surgeons, and inter-rater reliability was assessed.

RESULTS

Simethicone significantly improved DISE visibility (p = 0.03). "Best visibility" was achieved in 55% of cases with simethicone compared to 27% without simethicone (p = 0.02). Sub-analysis showed that only simethicone administration had a significant effect on visibility (p = 0.02). Inter-rater reliability between the grading surgeons was strong (Cohen-Kappa score 0.7, p < 0.001).

CONCLUSION

The findings suggest that simethicone enhances DISE visibility for OSA surgical planning. Further research should explore optimizing simethicone administration timing and the potential clinical implications for surgical outcomes and patient care.

Long-term complications associated with the management of sinonasal malignancies: a single center experience

Objective

The aim of this study was to review the long-term complications associated with treatment of patients with sinonasal malignancies (SNMs) and risk factors for these complications.

Methods

A retrospective analysis of all patients treated for SNMs at a tertiary care center between 2001 and 2018. A total of 77 patients were included. The primary outcome measure was post-treatment long-term complications.

Results

Overall, long-term complications were identified in 41 patients (53%), and the most common were sinonasal (22 patients, 29%) and orbital/ocular-related (18 patients, 23%). In a multivariate regression analysis, irradiation was the only significant predictor of long-term complications (p = 0.001, OR = 18.86, CI = 3.31-107.6). No association was observed between long-term complications and tumour stage, surgical modality, or radiation dose/modality. Mean radiation dose ≥ 50 Gy to the optic nerve was associated with grade ≥ 3 visual acuity impairment (100% vs 3%; p = 0.006). Radiation therapy for disease recurrence was associated with additional long-term complications (56% vs 11%; p = 0.04).

Conclusions

Treatment of SNMs has substantial long-term complications, which are significantly associated with radiation therapy.

Quality of life following lobectomy versus total thyroidectomy is significantly related to hypothyroidism

OBJECTIVE

The aim of the present study was to investigate the differences in quality of life (QOL) following complete or partial thyroidectomy and with regard to thyroid hormone replacement (LT4) therapy.

STUDY DESIGN

Patients who underwent thyroidectomy were asked to complete the validated thyroid-specific ThyPRO QOL questionnaire at least 6 months following surgery.

SETTING

Tertiary medical center.

METHODS

Thyroid specific QOL questionnaire analysis.

RESULTS

A total of 190 patients completed the ThyPRO questionnaire. Of them 89 patients had complete thyroidectomy and 101 patients had unilateral thyroid lobectomy. The total thyroidectomy group had significantly worse overall QOL self-assessment score than the lobectomy patients (p < 0.0001). Patients receiving LT4 therapy regardless of the extent of surgery, reported worse QOL compared to patients not receiving LT4.

CONCLUSIONS

Quality of life following thyroid surgery is significantly related to hypothyroidism and the requirement for LT4 therapy, rather to the extent of surgery. The best QOL was reported in patients treated with lobectomy who did not require LT4 therapy.

Thickness measurements taken with the spectralis OCT increase with decreasing signal strength

BACKGROUND

Optical coherence tomography (OCT) is used worldwide by clinicians to evaluate macular and retinal nerve fiber layer (RNFL) characteristics. It is frequently utilized to assess disease severity, progression and efficacy of treatment, and therefore must be reliable and reproducible.

OBJECTIVE

To examine the influence of signal strength on macular thickness parameters, macular volume measurement and RNFL thickness measured by spectral-domain optical coherence tomography (SD-OCT).

METHODS

Macular thickness parameters, macular volume measurement and RNFL thickness were measured by the Spectralis® OCT (Heidelberg Engineering, Heidelberg, Germany). In each eye, the focusing knob was adjusted to obtain 4 images with different signal strengths - Low (below 15), Moderate (15-20), Good (20-25) and Excellent (above 25). The relationship between signal strength and measured data was assessed using the mixed model procedure.

RESULTS

A total of 71 eyes of 41 healthy subjects were included. Central macular thickness, macular volume and mean RNFL thickness increased with decreasing signal strength. Specifically, eyes with excellent signal strength showed significantly thinner central macular thickness (p = 0.023), macular volume (p = 0.047), and mean RNFL thickness (p = 0.0139).

CONCLUSIONS

Higher signal strength is associated with lower macular thickness, macular volume and RNFL thickness measurements. The mean differences between excellent and low-quality measurements were small implicating that SD-OCT is a reliable imaging tool even at low quality scans. It is imperative that the physician compares the signal strength of all scans, as minute differences may alter results.

Classifying Medulloblastoma Subgroups Based on Small, Clinically Achievable Gene Sets

As treatment protocols for medulloblastoma (MB) are becoming subgroup-specific, means for reliably distinguishing between its subgroups are a timely need. Currently available methods include immunohistochemical stains, which are subjective and often inconclusive, and molecular techniques—e.g., NanoString, microarrays, or DNA methylation assays—which are time-consuming, expensive and not widely available. Quantitative PCR (qPCR) provides a good alternative for these methods, but the current NanoString panel which includes 22 genes is impractical for qPCR. Here, we applied machine-learning–based classifiers to extract reliable, concise gene sets for distinguishing between the four MB subgroups, and we compared the accuracy of these gene sets to that of the known NanoString 22-gene set. We validated our results using an independent microarray-based dataset of 92 samples of all four subgroups. In addition, we performed a qPCR validation on a cohort of 18 patients diagnosed with SHH, Group 3 and Group 4 MB. We found that the 22-gene set can be reduced to only six genes (IMPG2, NPR3, KHDRBS2, RBM24, WIF1, and EMX2) without compromising accuracy. The identified gene set is sufficiently small to make a qPCR-based MB subgroup classification easily accessible to clinicians, even in developing, poorly equipped countries.

Radioiodine therapy induced sialadenitis versus chronic idiopathic sialadenitis-Presentation and outcomes

BACKGROUND

This study explores the unique characters of high dose radioactive iodine (RAI) induced chronic sialadenitis.

METHODS

A retrospective study of patients having received salivary endoscopy and followed in our outpatient clinic.

RESULTS

A total of 100 patients met the inclusion criteria, 75 were diagnosed with chronic idiopathic sialoadenitis and 25 with radio-iodine induced sialoadenitis (RIS). The main complaint in both groups was swelling of the parotid gland. Pain, dysphagia, and xerostomia were observed considerably more in the RIS group. During sialo-endoscopy, fibrosis of the Stensen's duct was more common in the RIS group (p = 0.003). RIS patients group generally managed better with interventional endoscopic treatment alone (80% vs. 46%).

CONCLUSION

RIS patients have distinct clinical characteristics. There may be a collateral muscular damage to the masticatory muscles. Fibrosis and parenchymal damage are major findings during sialendoscopy. Sialendoscopy is a safe and efficient treatment for RAI induced sialadenitis.

Refractive outcomes of high-magnitude astigmatism correction using femtosecond LASIK versus transepithelial PRK

PURPOSE

To compare the outcomes of femtosecond laser assisted in situ keratomileusis (FS-LASIK) with transepithelial photorefractive keratectomy (T-PRK) for the correction of high-grade astigmatism.

METHODS

Medical records of patients with astigmatism of 2 diopters (D) or higher, who were treated with FS-LASIK or T-PRK in 2013 through 2014 at a private practice laser clinic, were retrospectively analyzed. Efficacy, safety, predictability and vector analysis of astigmatism correction were compared between the treatment groups.

RESULTS

The study included 93 eyes treated with FS-LASIK and 186 eyes treated with T-PRK. No significant differences in postoperative spherical equivalent (-0.10 ± 0.7 D and -0.11 ± 0.7 D, respectively, p = 0.958) and postoperative refractive astigmatism (0.79 ± 0.54 D and 0.82 ± 0.63 D, respectively, p = 0.685) were demonstrated. A significant advantage of FS-LASIK over T-PRK was seen for the efficacy (1.00 ± 0.18 and 0.86 ± 0.22, respectively, p < 0.001) and safety (1.03 ± 0.17 and 0.89 ± 0.21, respectively, p < 0.001) indices. Results remain statistically significant in a multivariate analysis model. Vector analysis for the astigmatism correction showed no significant difference between the surgery methods in the surgically induced astigmatism, difference vector, correction index and index of success.

CONCLUSION

Both procedures demonstrated desirable post-operative SE outcomes for high-grade astigmatism correction. However, FS-LASIK achieved better results than T-PRK in the efficacy and safety parameters.

Prophylactic central neck dissection has no advantage in patients with metastatic papillary thyroid cancer to the lateral neck

BACKGROUND

Papillary thyroid cancer (PTC) usually metastasizes via lymphatic channels in a sequential fashion, first to the central compartment, followed by the lateral neck. PTC patients diagnosed with lateral neck disease (N1b) without proof for central involvement traditionally undergo prophylactic central neck dissection (pCND). However, substantial evidence on outcomes to support this approach is lacking.

MATERIALS AND METHODS

We conducted a dual center retrospective study to compare the rate of central neck recurrence between N1b PTC patients undergoing pCND and those spared pCND. All patients diagnosed with N1b PTC who underwent total thyroidectomy and lateral neck dissections with or without pCND between January 1998 and December 2015 were included in this study. The rates of central neck recurrences were compared between the groups.

RESULTS

The 111 patients who met the inclusion criteria were 44 females (39.6%) and 67 males (60.4%), with a mean age of 50.2 ± 17.7 years, and a mean follow-up of 10.2 ± 5.3 years. Sixty patients (54.1%) underwent a pCND and 51 patients (45.9%) did not (non-pCND). During follow-up, 18 patients (16.2%) had level VI recurrences, 13 in the pCND group and 5 in the non-pCND group. Cox-regression models with propensity scoring did not reveal any inclination or an advantage for performing pCND.

CONCLUSION

The present study demonstrated no advantage in performing pCND to prevent central neck recurrence among PTC patients with lateral neck involvement only. These findings question the need for pCND in patients without clinical evidence of central neck disease.

The bacteriology of recurrent acute exacerbations of chronic rhinosinusitis: a longitudinal analysis

PURPOSE

The purpose of this study was to describe the microbiology of recurrent acute exacerbations of chronic rhinosinusitis over time.

METHODS

Retrospective review of patients with recurrent acute exacerbations of chronic rhinosinusitis who underwent endoscopic-guided cultures during acute exacerbations of chronic rhinosinusitis.

RESULTS

386 cultures were obtained from 112 patients during recurrent acute exacerbations of CRS. A change of bacterial isolates during the course of recurrent exacerbations was observed in 68% (76/112) of patients, necessitating a change of treatment in 40% (45/112). The main risk factor for the subsequent change in cultures was polymicrobial growth. Sinus surgery was not associated with subsequent change in cultured isolates. Resistant strains developed in 11.6% (13/112) of patients, of whom those with abnormal mucociliary clearance being at the highest risk.

CONCLUSION

Repeated middle meatal cultures should be considered in patients with recurrent exacerbations of CRS, particularly in cases not responding to standard therapy.

Detecting Recurrence Following Lobectomy for Thyroid Cancer: Role of Thyroglobulin and Thyroglobulin Antibodies

BACKGROUND

The use of thyroglobulin (Tg) and thyroglobulin antibodies (TgAb) for detecting disease recurrence is well validated following total thyroidectomy and radioiodine ablation. However, limited data are available for patients treated with thyroid lobectomy.

METHODS

Patients who had lobectomy for papillary thyroid cancer followed for >1 year, with sufficient data on Tg and TgAb, including subgroup analysis for Hashimoto's thyroiditis and contralateral nodules.

RESULTS

One-hundred sixty-seven patients met the inclusion criteria. Average tumor size was 9.5 ± 6 mm. Following lobectomy, Tg was 12.1 ± 14.8 ng/mL. Of 52 patients with Hashimoto's thyroiditis, 38% had positive TgAb with titers of 438 ± 528 IU/mL, and in patients without TgAb the mean Tg level was 14.7 ± 19.0 ng/mL. In 34 patients with contralateral nodules ≥1 cm, Tg was 15.3 ± 17 ng/mL. During the first 2 years of follow-up, Tg declined ≥1 ng/mL in 42% of patients (by 5.1 ± 3.7 ng/mL), remained stable in 22%, and increased in 36% (by 4.9 ± 5.7 ng/mL). During a mean follow-up of 6.5 years (78 ± 43.5 months), 18 patients had completion thyroidectomy and 12 were diagnosed with contralateral cancer (n = 8) or lymph node metastases (n = 4). In patients with recurrence followed for >2 years, there was a rise in Tg in 3 cases, Tg was stable in 2 cases, and in 1 TgAb decreased from 1534 to 276 IU/mL despite metastatic lymph nodes. Basal Tg and Tg dynamics did not predict disease recurrence.

CONCLUSIONS

Serum thyroglobulin used independently is of limited value for predicting or detecting disease recurrence following thyroid lobectomy. Other potential roles of Tg, such as detecting distant metastases following lobectomy, should be further studied.

Questioning the Justification of Frontal Sinusotomy for Odontogenic Sinusitis

PURPOSE

Odontogenic sinusitis (OS) can be caused by infectious conditions of the posterior maxillary teeth. The maxillary sinus has been most often involved because of its proximity to the posterior maxillary teeth. Often the anterior ethmoids and frontal sinuses will be involved by the infective process. The underlying odontogenic condition must be addressed before or during sinus surgery. The role of frontal sinusotomy in the treatment of these patients has been poorly described. Our objective was to present the surgical outcomes of patients with OS involving the frontal sinus who had undergone middle meatal antrostomy alone.

PATIENTS AND METHODS

A prospective analysis of all patients who had undergone surgery at a single tertiary center to treat OS involving the frontal sinus from November 2015 to December 2018 was performed. Their preoperative assessment findings, surgical findings, and postoperative outcomes were analyzed.

RESULTS

A total of 45 patients (23 men and 22 women), with a median age of 57 years (range, 20 to 83 years), were enrolled in the present study. All anterior sinuses (frontal, anterior ethmoids, and maxillary sinuses) were clinically and radiographically involved in all the patients. Each patient underwent endoscopic wide maxillary middle meatal antrostomy concurrent with dental intervention. The average follow-up was 7 months. No signs of active frontal disease were detected by postoperative endoscopy in any patient, and no patient required revision surgery.

CONCLUSIONS

The results from the present study have shown that no justification exists for frontal sinusotomy for the treatment of OS involving the frontal sinus. Frontal sinusitis is a secondary infectious and inflammatory process that will resolve once the underlying odontogenic condition has healed and wide middle meatal antrostomy has been performed.

Age- and Gender-Related Characteristics of Corneal Refractive Parameters in a Large Cohort Study

PURPOSE

To characterize age- and sex-related changes in corneal refractive parameters in myopic and hyperopic patients undergoing refractive surgery.

DESIGN

A retrospective cross-sectional study.

METHODS

Analysis of demographic and refractive parameters of myopic and hyperopic patients who underwent laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) between January 2000 and December 2014 at the Care-Vision Laser Centers, Tel-Aviv, Israel.

RESULTS

A total of 62,422 eyes of 31,211 patients were included. With advancing age, refractive surgery was performed for lower magnitudes of myopia and hyperopia. The magnitude of cylinder was higher in men than in women in both myopic and hyperopic patients. In comparison, women were significantly more myopic than men (spherical equivalent of -3.73 diopter [D] versus -4.07 D; P < 0.01). The myopic group sphere (r = 0.044; P < 0.001) had a positive correlation with age, whereas other parameters had a negative correlation with age: astigmatism (r = -0.09; P < 0.001), best-correct visual acuity (BCVA) (r = -0.04; P < 0.001), flat K (r = -0.09; P < 0.001), steep K (r = -0.06; P < 0.001), average K (r = -0.07; P < 0.001), and J0 (r = -0.05; P < 0.001). For hyperopic patients, astigmatism (r = 0.35; P < 0.001), BCVA (r = 0.11; P < 0.001), flat K (r = 0.30; P < 0.001), average K (0.14; P < 0.001), and central corneal thickness (r = 0.10; P < 0.001) correlated positively with age, whereas sphere (r = -0.23; P < 0.001), J0 (r = -0.31; P < 0.001), and overall blurring strength (r = -0.31; P < 0.001) had negative correlations with age.

CONCLUSIONS

This large cohort study shows age- and sex-related refractive parameters among myopic and hyperopic patients seeking refractive surgery. These parameters can explain and predict trends in patients attending refractive surgery.

Risk factors predicting steroid-induced ocular hypertension after photorefractive keratectomy

PURPOSE

To assess the risk factors contributing to steroid-induced ocular hypertension after photorefractive keratectomy (PRK).

SETTING

Care Laser Centers, Tel Aviv, Israel.

DESIGN

Retrospective case series.

METHODS

Patients having PRK between January 2000 and December 2015 were followed for at least 3 months. Intraocular pressure (IOP) was measured using the Goldmann applanation tonometer after 1 week and after 1, 3, and 6 months. Ocular hypertension was defined as an IOP elevation of 25% while on topical steroid treatment (minimum 28 mm Hg) followed by an IOP drop of 25% when steroid treatment was discontinued.

RESULTS

The study comprised 1783 patients (3566 eyes). The mean age of the patients was 26.95 years ± 7.56 (SD), and 54.85% were men. A total of 106 eyes (2.97%) were steroid responders. The responder group had a higher proportion of men than the nonresponder group (70.75% versus 29.25%; P < .001), higher central corneal thickness (CCT) (531.9 ± 40.2 μm versus 521.2 ± 40.9 μm; P = .008), lower mean keratometry (K) power (43.39 ± 1.84 diopters [D] versus 44.08 ± 1.88 D; P < .001), higher proportion of high myopia (>6.0 D) (31.13% versus 22.18%; P = .03), and higher rate of postoperative corneal haze (16.98% versus 4.25%; P < .001) and were treated postoperatively with more potent steroids. All factors remained significant in the multivariate analysis.

CONCLUSION

Significant factors associated with post-PRK ocular hypertension were male sex, high CCT, a low mean K reading, high myopia, corneal haze, and treatment with stronger steroids such as dexamethasone.

Research productivity across different ophthalmic subspecialties in the United States

Background

The purpose of this study was to compare the h-index, and subsequently the research productivity, among different ophthalmic subspecialties in the United States.

Methods

A cohort of over 15,000 academic ophthalmologists residing in the United States (US) was identified out of the physician list of the American Academy of Ophthalmology. Of them, 1000 ophthalmologists with at least one publication were randomly retrieved, 100 in each of the following 10 subspecialties: cataract, cornea/external disease, glaucoma, medical retina, neuro-ophthalmology, pediatric ophthalmology, plastic/reconstructive ophthalmology, refractive surgery, retina/vitreous surgery and uveitis. Data collected included: number of published papers, h-index score, annual increase in h-index and the mean number of authors on each paper.

Results

The mean h-index amongst all subspecialties was 9.87 ± 13.90, and the mean average annual increase in h-index was 0.22 ± 0.21. The mean number of papers published was 37.20 ± 80.08 and the mean number of authors on each paper was 3.39 ± 0.84. Uveitis was the most prolific subspecialty in mean number of papers (74.78 ± 131.37), in mean h-index (16.69 ± 20.00) and in mean annual increase in h-index (0.35 ± 0.28). The least fertile subspecialty with regards to research was cataract with 11.06 ± 27.65 mean number of papers, a mean h-index of 3.89 ± 5.84, and a mean annual increase in h-index of 0.11 ± 0.11.

Conclusions

This study describes the research productivity in each ophthalmic subspecialty in the US, thus providing information on the research performance of each field and on the expected academic accomplishments within it.

Foreign Body Aspiration in Infants and Older Children: A Comparative Study

BACKGROUND

Foreign body aspiration (FBA) is a major cause of morbidity and mortality in children. It is a preventable event that predominates in preschool age. The signs and symptoms mimic respiratory diseases common in the same age-group. We compared FBA in infants to FBA in older children.

METHODS

Retrospective analysis of all the cases of suspected FBA of children under the age of 18 years hospitalized at one medical center during 2002 to 2016. We analyzed the data according to age: up to 1 year (infants) and 1 to 18 years.

RESULTS

One hundred seventy-five children with suspected FBA were admitted; of whom, 27 (15%) were infants and 148 (85%) were older children (age 1-18 years). For the 2 age groups, adults witnessed 85% and 73%, respectively, of the incidents (P = .4). In the neonate group, 48% presented with normal X-ray findings compared to only 20% in the older group; 15% of the older group had a positive chest X-ray for a foreign body, while none had such in the infants' group (P = .01). For the 2 age groups, the majority of the FBs found were from organic origin. About half of the patients were diagnosed and managed within 24 hours of the aspiration event. In 10%, repeated bronchoscopy was performed due to a retained FB remnant. In a multivariate analysis, signs and symptoms (P < .05), location of the FB (P < .001), and witnessed aspiration (P < .001) were independent prognostic factors for the length of hospitalization.

CONCLUSION

Foreign body aspiration is not uncommon in young infants; the management is challenging due to small airways, the need to use smaller bronchoscopes, and the lack of working channel forces in pediatric bronchoscopes.

Visual acuity in patients with keratoconus: a comparison with matched regular myopic astigmatism

PURPOSE

To compare uncorrected distance visual acuity (UDVA) and best-corrected distance visual acuity (CDVA) between patients with keratoconus (KC) and matched patients with regular myopic astigmatism.

METHODS

This retrospective study included consecutive patients diagnosed with KC between 2008 and 2013 at Care-Vision Laser Centers, Tel-Aviv, Israel, and matched patients with regular myopic astigmatism. Data included were central corneal thickness (CCT), spherical equivalent (SE), cylinder (CYL), mean keratometric power, maximum keratometric power (K_max), UDVA, CDVA, and defocus equivalent (DEQ).

RESULTS

The KC group included 734 patients with a mean age of 33.8 ± 9.5 years. The matched, control group included 1462 patients with a mean age of 33.2 ± 9.7 years (p = 0.14). The mean SE and CYL of the KC group were - 3.34 ± 3.29D and - 3.01 ± 1.99D, respectively, compared to - 3.34 ± 2.92D (p = 0.98) and - 2.97 ± 1.35 (p = 0.58). Mean K (46.8 ± 3.3D versus 44.0 ± 1.8D, p < 0.0001) and K_max (48.4 ± 4.0D versus 45.3 ± 2.0D, p < 0.0001) were statically significant higher in the KC group. CCT was significantly thinner in the KC group (444 ± 49 versus 527 ± 40 μm, p < 0.0001). The KC group had a better UDVA than the non-KC group (1.10 ± 0.68 versus 1.22 ± 0.64 logMAR, p < 0.0001). CDVA was significantly lower in the KC group (p < 0.001).

CONCLUSIONS

For defocus equivalents above 6D, the KC group had better UDVA than the non-KC group in spite of worse CDVA.

Positive results bias in pediatric ophthalmology scientific publications

Previous studies in several fields of medicine, including general ophthalmology, have revealed a positive results bias, demonstrating an association between the results of a trial and the impact factor (IF) of the journal in which it was published. We hypothesized that randomized clinical studies in pediatric ophthalmology with positive results have a greater chance of publication in journals with a higher IF than those with negative results. We analyzed 174 randomized, controlled trials conducted in the field of pediatric ophthalmology, which were retrieved from PubMed. Each study was classified as having either a positive or a negative result. A positive result was defined as a study in which there was a statistically significant difference between groups (P < 0.05). No difference was found in IF between negative and positive outcomes, after statistically adjusting for the number of subjects and year of publication. We concluded that, unlike general ophthalmology, positive results bias probably does not occur in the field of pediatric ophthalmology.

Bevacizumab dosing every 2 weeks for neovascular age-related macular degeneration refractory to monthly dosing

PURPOSE

To evaluate intravitreal bevacizumab every 2 weeks (biweekly) in refractory neovascular age-related macular degeneration (nAMD).

STUDY DESIGN

Retrospective study.

METHODS

A retrospective study of consecutive nAMD patients unresponsive to monthly intravitreal anti-vascular endothelial growth factor (VEGF) switched to 3-4 biweekly injections.

RESULTS

Twenty-seven eyes of patients aged 82.08  ± 6.85 years were included. Prior to the 2-week interval bevacizumab injections, 74.1% (n=20) were treated with both bevacizumab and ranibizumab, 11.1% (3 eyes) also received aflibercept and 14.8% (4 eyes) had received prior treatment of monthly bevacizumab (average number of injections 21.5 ± 6.7). Best corrected visual acuity (BCVA) remained stable between baseline (logMAR 0.72± 0.60) and follow-up (0.76± 0.66) (p=0.41). Mean central macular thickness and macular volume did not change significantly between baseline and follow-up (p=0.35 and p=0.60, respectively). Six eyes (22.2%) showed morphologic anatomic improvements, while 19 eyes (70.4%) were stable and two eyes (7.4%) deteriorated from baseline. Subretinal fluid completely resolved in 3 of the eyes and improved in the other 3 eyes and in this group (22.2%) both central macular thickness (326.2 ± 101.4 versus 297.5 ± 97.2, p=0.002) and macular volume (8.69 ± 1.69 versus 8.22 ± 1.43, p=0.03) were significantly reduced. No adverse events were observed in any of the treated eyes.

CONCLUSION

This study demonstrates that biweekly bevacizumab injections are effective in nearly one-quarter of nAMD non-responders with no adverse events reported. Switching earlier, rather than later, to this low cost modality may be of benefit for a portion of non-responders to conventional treatment.

Rosmarinic Acid Restores Complete Transparency of Sonicated Human Cataract Ex Vivo and Delays Cataract Formation In Vivo

Cataract, the leading cause of vision impairment worldwide, arises from abnormal aggregation of crystallin lens proteins. Presently, surgical removal is the only therapeutic approach. Recent findings have triggered renewed interest in development of non-surgical treatment alternatives. However, emerging treatments are yet to achieve full and consistent lens clearance. Here, the first ex vivo assay to screen for drug candidates that reduce human lenticular protein aggregation was developed. This assay allowed the identification of two leading compounds as facilitating the restoration of nearly-complete transparency of phacoemulsified cataractous preparation ex vivo. Mechanistic studies demonstrated that both compounds reduce cataract microparticle size and modify their amyloid-like features. In vivo studies confirmed that the lead compound, rosmarinic acid, delays cataract formation and reduces the severity of lens opacification in model rats. Thus, the ex vivo assay may provide an initial platform for broad screening of potential novel therapeutic agents towards pharmacological treatment of cataract.

Infliximab exerts a dose-dependent effect on retinal safety in the albino rabbit

PURPOSE

To assess the retinal toxicity of an intravitreal injection of infliximab, a monoclonal antibody to tumor necrosis factor α, in a rabbit model.

MATERIALS AND METHODS

Two groups of adult albino rabbits (n = 5) received intravitreal injections of infliximab (0.1 ml) in the study eye and balanced salt solution (BSS, 0.1 ml) in the control eye at baseline. Group 1 was administered with 1.5 mg/0.1 ml, and group 2 was injected with 7.5 mg/0.1 ml of infliximab solution. Electroretinography (ERG) was performed at baseline and at 1, 7, 30, and 45 days after the injection. Visual evoked potentials (VEPs) were recorded at 7 and 45 days after the injection. After the last electrophysiological assessment, the rabbits were euthanized and retinal histopathology and immunhistochemistry for glial fibrillary acidic protein (GFAP) were performed.

RESULTS

ERG responses demonstrated no significant deficit in retinal function in eyes injected with infliximab. Mean dark-adapted a-wave and b-wave maximal amplitude and semi-saturation constant values at baseline and throughout the 45 days of follow-up after the injection indicated no remarkable difference in outer retinal function between the control and experimental eyes. VEP responses were similar at each time point (7 and 45 days). No difference was seen in retinal histopathology and immunocytochemistry sections in eyes receiving the 1.5 mg/0.1 ml dose compared to the control eyes. However, increased GFAP labeling in retinal Müller cells was detected in rabbit eyes treated with the 7.5 mg/0.1 ml dose.

CONCLUSIONS

Intravitreal injection of 1.5 mg/0.1 ml infliximab dose has no toxic effect on the integrity (functional or structural) of the retina in rabbits. A higher dose of 7.5 mg/0.1 ml may be slightly toxic as suggested by positive Müller cell GFAP expression. Additional studies of retinal toxicity at higher doses and after multiple injections are needed to establish the retinal safety of intravitreal infliximab therapy in humans.

Trends in impact factors of ophthalmology journals

Purpose:

To test whether there is an association between the growth in the number of ophthalmic journals in the past years and their mean and maximum impact factor (IF) as a common sign of scientific proliferation.

Methods:

Using data from the 2013 Journal Citation Report database a study of the major clinical medical fields was conducted to assess the correlation between the number of journals and maximum IF in a given field in the year 2013. In the field of ophthalmology, we examined the correlation between year, number of journals, mean IF and maximum IF in the field of ophthalmology throughout the years 2000–2013.

Results:

In the major medical fields, a positive correlation was found between the number of journals and the maximum IF (quadratic R² = 0.71, P < 0.001). When studying the field of ophthalmology a positive correlation between the number of journals and mean IF (R² = 0.84, P < 0.001) and between number of journals and maximum IF (R² = 0.71, P < 0.001) was detected.

Conclusions:

Our findings suggest that the variation in the IF can be explained by the number of journals in the field of ophthalmology. In the future, the formation of additional ophthalmology journals is likely to further increase the IFs of existing journals.

Relationship between macular thickness measurement and signal strength using Stratus optical coherence tomography

Purpose

To examine the relationship between signal strength and macular thickness as measured by Stratus optical coherence tomography (OCT)’s fast macular thickness protocol in healthy subjects.

Methods

In this prospective cross-sectional study 79 eyes of 42 healthy subjects were enrolled. The age, gender, and eye (right vs left) of each subject were recorded. The Stratus OCT fast macular thickness scan protocol was used and the macular thickness was measured with retinal thickness map analysis. Each eye was imaged at least six times to acquire images with signal strengths of 4, 5, 6, 7, 8, and 9 out of 10 via adjustment of the focusing knob. The OCT parameters included in the analysis were thickness in the central 1 mm and in the different quadrants in the 3-mm area.

Results

Overall 79 eyes of 42 patients with a mean age of 38.4±12.4 were included. There was no significant difference between the signal strength measurements obtained with different signal strengths in the central thickness (P=0.20). In the superior, nasal, inferior, and temporal quadrants, a signal strength of 8 demonstrated up to 3 µm thicker measurements than a signal strength of 5 (P<0.05). In general linear regression analysis, after accounting for age and gender, signal strength did not remain a significant predictor of thickness in any quadrant.

Conclusions

When using fast map macular measurements, a signal strength of 5 is clinically as efficient as a signal strength of 8 in measuring macular thickness in all quadrants. Insisting on higher signal strength may not be necessary.