Small Extracellular Vesicles Promote Stiffness-mediated Metastasis.

Tissue stiffness is a critical prognostic factor in breast cancer and is associated with metastatic progression. Here we show an alternative and complementary hypothesis of tumor progression whereby physiologic matrix stiffness affects the quantity and protein cargo of small extracellular vesicles (EV) produced by cancer cells, which in turn aid cancer cell dissemination. Primary patient breast tissue released by cancer cells on matrices that model human breast tumors (25 kPa; stiff EVs) feature increased adhesion molecule presentation (ITGα2ß1, ITGα6ß4, ITGα6ß1, CD44) compared with EVs from softer normal tissue (0.5 kPa; soft EVs), which facilitates their binding to extracellular matrix proteins including collagen IV, and a 3-fold increase in homing ability to distant organs in mice. In a zebrafish xenograft model, stiff EVs aid cancer cell dissemination. Moreover, normal, resident lung fibroblasts treated with stiff and soft EVs change their gene expression profiles to adopt a cancer-associated fibroblast phenotype. These findings show that EV quantity, cargo, and function depend heavily on the mechanical properties of the extracellular microenvironment. SIGNIFICANCE: Here we show that the quantity, cargo, and function of breast cancer-derived EVs vary with mechanical properties of the extracellular microenvironment.

Small extracellular vesicles promote stiffness-mediated metastasis.

Tissue stiffness is a critical prognostic factor in breast cancer and is associated with metastatic progression. Here we show an alternative and complementary hypothesis of tumor progression whereby physiological matrix stiffness affects the quantity and protein cargo of small EVs produced by cancer cells, which in turn drive their metastasis. Primary patient breast tissue produces significantly more EVs from stiff tumor tissue than soft tumor adjacent tissue. EVs released by cancer cells on matrices that model human breast tumors (25 kPa; stiff EVs) feature increased adhesion molecule presentation (ITGα 2 ß 1 , ITGα 6 ß 4 , ITGα 6 ß 1 , CD44) compared to EVs from softer normal tissue (0.5 kPa; soft EVs), which facilitates their binding to extracellular matrix (ECM) protein collagen IV, and a 3-fold increase in homing ability to distant organs in mice. In a zebrafish xenograft model, stiff EVs aid cancer cell dissemination through enhanced chemotaxis. Moreover, normal, resident lung fibroblasts treated with stiff and soft EVs change their gene expression profiles to adopt a cancer associated fibroblast (CAF) phenotype. These findings show that EV quantity, cargo, and function depend heavily on the mechanical properties of the extracellular microenvironment.

Calcium Sulfate Microparticle Size Modification for Improved Alginate Hydrogel Fabrication and Its Application in 3D Cell Culture.

Calcium ion-crosslinked alginate hydrogels are widely used as a materials system for investigating cell behavior in 3D environments in vitro . Suspensions of calcium sulfate particles are often used as the source of Ca 2+ to control the rate of gelation. However, the instability of calcium sulfate suspensions can increase chances of reduced homogeneity of the resulting gel and requires researcher's proficiency. Here, we show that ball-milled calcium sulfate microparticles with smaller sizes can create more stable crosslinker suspensions than unprocessed or simply autoclaved calcium sulfate particles. In particular, 15 µm ball-milled calcium sulfate microparticles result in gels that are more homogeneous with a balanced gelation rate, which facilitates fabrication of gels with consistent mechanical properties and reliable performance for 3D cell culture. Overall, these microparticles represent an improved method for alginate hydrogel fabrication that can increase experimental reliability and quality for 3D cell culture.

Deep learning identification of stiffness markers in breast cancer.

While essential to our understanding of solid tumor progression, the study of cell and tissue mechanics has yet to find traction in the clinic. Determining tissue stiffness, a mechanical property known to promote a malignant phenotype in vitro and in vivo, is not part of the standard algorithm for the diagnosis and treatment of breast cancer. Instead, clinicians routinely use mammograms to identify malignant lesions and radiographically dense breast tissue is associated with an increased risk of developing cancer. Whether breast density is related to tumor tissue stiffness, and what cellular and non-cellular components of the tumor contribute the most to its stiffness are not well understood. Through training of a deep learning network and mechanical measurements of fresh patient tissue, we create a bridge in understanding between clinical and mechanical markers. The automatic identification of cellular and extracellular features from hematoxylin and eosin (H&E)-stained slides reveals that global and local breast tissue stiffness best correlate with the percentage of straight collagen. Importantly, the percentage of dense breast tissue does not directly correlate with tissue stiffness or straight collagen content.

Measures of Bone Mineral Carbonate Content and Mineral Maturity/Crystallinity for FT-IR and Raman Spectroscopic Imaging Differentially Relate to Physical-Chemical Properties of Carbonate-Substituted Hydroxyapatite.

Bone mineral carbonate content assessed by vibrational spectroscopy relates to fracture incidence, and mineral maturity/ crystallinity (MMC) relates to tissue age. As FT-IR and Raman spectroscopy become more widely used to characterize the chemical composition of bone in pre-clinical and translational studies, their bone mineral outcomes require improved validation to inform interpretation of spectroscopic data. In this study, our objectives were (1) to relate Raman and FT-IR carbonate:phosphate ratios calculated through direct integration of peaks to gold-standard analytical measures of carbonate content and underlying subband ratios; (2) to relate Raman and FT-IR MMC measures to gold-standard analytical measures of crystal size in chemical standards and native bone powders. Raman and FT-IR direct integration carbonate:phosphate ratios increased with carbonate content (Raman: p < 0.01, R2 = 0.87; FT-IR: p < 0.01, R2 = 0.96) and Raman was more sensitive to carbonate content than the FT-IR (Raman slope + 95% vs FT-IR slope, p < 0.01). MMC increased with crystal size for both Raman and FT-IR (Raman: p < 0.01, R2 = 0.76; FT-IR p < 0.01, R2 = 0.73) and FT-IR was more sensitive to crystal size than Raman (c-axis length: slope FT-IR MMC + 111% vs Raman MMC, p < 0.01). Additionally, FT-IR but not Raman spectroscopy detected differences in the relationship between MMC and crystal size of carbonated hydroxyapatite (CHA) vs poorly crystalline hydroxyapatites (HA) (slope CHA + 87% vs HA, p < 0.01). Combined, these results contribute to the ability of future studies to elucidate the relationships between carbonate content and fracture and provide insight to the strengths and limitations of FT-IR and Raman spectroscopy of native bone mineral.

Risk of Anaplastic Large-Cell Lymphoma (ALCL) in Cases of Late Seroma Formation After Breast Implant Insertion.

Purpose: The aim of this study was to determine the odds ratio of anaplastic large-cell lymphoma in late seroma formation. Methods: In a PubMed search, 415 articles were found using the terms "breast implant AND seroma" (n = 232), "breast implant AND effusion" (n = 42), and "anaplastic large cell lymphoma AND breast (n = 141). Sixty-seven abstracts were read, and 27 full articles were reviewed. Results: Three articles reported the incidence of late seroma in breast implants, with a total of 75 seromas out of 48,211 implants (0.16%). One article reported 48 cases of non-Hodgkin lymphoma from 43,537 implants (0.11%). Another article reported that 11 patients had anaplastic large-cell lymphoma among 389 primary lymphoma of the breast (2.83%). Two articles reported 143 seromas out of 236 anaplastic large-cell lymphomas (60.59%). The risk of anaplastic large-cell lymphoma was significantly higher in the patients having late seroma than those without seroma (odds ratio = 998.93; 95% confidence interval, 768.90-1297.78; P < .001). The incidence of anaplastic large-cell lymphoma in seroma was calculated by dividing the number of anaplastic large cell lymphomas with seroma (n = 143) by total seroma (N = 11,843), which resulted in an incidence of 1.21%. The expected incidence of anaplastic large-cell lymphoma in seroma was 1.21%. Conclusion: If late seroma develops after breast implant insertion, ultrasonography-guided aspiration should be performed, with enzyme-linked-immunosorbent serologic assay for CD30.

Tissue-engineered blood-brain barrier models via directed differentiation of human induced pluripotent stem cells.

Three-dimensional (3D) tissue-engineered models of the blood-brain barrier (BBB) recapitulate in vivo shear stress, cylindrical geometry, and cell-ECM interactions. Here we address four issues associated with BBB models: cell source, barrier function, cryopreservation, and matrix stiffness. We reproduce a directed differentiation of brain microvascular endothelial cells (dhBMECs) from two fluorescently labeled human induced pluripotent stem cell lines (hiPSCs) and demonstrate physiological permeability of Lucifer yellow over six days. Microvessels formed from cryopreserved dhBMECs show expression of BBB markers and maintain physiological barrier function comparable to non-cryopreserved cells. Microvessels displaying physiological barrier function are formed in collagen I hydrogels with stiffness matching that of human brain. The dilation response of microvessels was linear with increasing transmural pressure and was dependent on matrix stiffness. Together these results advance capabilities for tissue-engineered BBB models.

Clinical Evaluation of Commercial Atlas-Based Auto-Segmentation in the Head and Neck Region.

Background: While atlas segmentation (AS) has proven to be a time-saving and promising method for radiation therapy contouring, optimal methods for its use have not been well-established. Therefore, we investigated the relationship between the size of the atlas patient population and the atlas segmentation auto contouring (AC) performance. Methods: A total of 110 patients' head planning CT images were selected. The mandible and thyroid were selected for this study. The mandibles and thyroids of the patient population were carefully segmented by two skilled clinicians. Of the 110 patients, 100 random patients were registered to 5 different atlas libraries as atlas patients, in groups of 20 to 100, with increments of 20. AS was conducted for each of the remaining 10 patients, either by simultaneous atlas segmentation (SAS) or independent atlas segmentation (IAS). The AS duration of each target patient was recorded. To validate the accuracy of the generated contours, auto contours were compared to manually generated contours (MC) using a volume-overlap-dependent metric, Dice Similarity Coefficient (DSC), and a distance-dependent metric, Hausdorff Distance (HD). Results: In both organs, as the population increased from n = 20 to n = 60, the results showed better convergence. Generally, independent cases produced better performance than simultaneous cases. For the mandible, the best performance was achieved by n = 60 [DSC = 0.92 (0.01) and HD = 6.73 (1.31) mm] and the worst by n = 100 [DSC = 0.90 (0.03) and HD = 10.10 (6.52) mm] atlas libraries. Similar results were achieved with the thyroid; the best performance was achieved by n = 60 [DSC = 0.79 (0.06) and HD = 10.17 (2.89) mm] and the worst by n = 100 [DSC = 0.72 (0.13) and HD = 12.88 (3.94) mm] atlas libraries. Both IAS and SAS showed similar results. Manual contouring of the mandible and thyroid required an average of 1,044 (±170.15) seconds, while AS required an average of 46.4 (±2.8) seconds. Conclusions: The performance of AS AC generally increased as the population of the atlas library increased. However, the performance does not drastically vary in the larger atlas libraries in contrast to the logic that bigger atlas library should lead to better results. In fact, the results do not vary significantly toward the larger atlas library. It is necessary for the institutions to independently research the optimal number of subjects.

The Boomerang Epicanthoplasty: A Technique That Avoids Hooding.

Redraping is an increasingly common epicanthoplasty method. However, hooding usually remains at the medial part of the upper eyelid. The authors innovated a modification of redraping epicanthoplasty using excision, resulting in a boomerang-shaped defect that does not lead to hooding of the medial upper eyelid.Medial line (M-line) was drawn at the most medial point of the palpebral fissure. The canthus point (C-point) was marked approximately 1 to 3 mm laterally from the M-point, depending on the amount of widening needed. From the C-point, upper incision was designed to meet the double eyelid line. A V-shaped lower incision was designed 3 to 4 mm below the ciliary margin. A flap was elevated about 7 mm superiorly, 10 mm medially, and 5 mm inferiorly. The elevated skin flap was redraped and the M'-point, which reflected the M-point on the redraped skin, was marked. A curvilinear incision line reflecting previous incision lines was drawn. The crescent-shaped excess skin was excised and the medial canthus was retracted medially, and then the boomerang-shaped defect was observed. The M-point and M'-point were coapted with a suture. The dog-ear at the lower side was trimmed.The 525 patients were followed up for ≥3 months postoperatively. The average increase in the palpebral fissure length was 1.2 ±â€Š0.5 mm. The average decrease in the interepicanthal distance was 2.4 ±â€Š0.9 mm. The average satisfaction score was 4.6 ±â€Š0.6.Boomerang epicanthoplasty can prevent hooding on the medial aspect of the upper eyelid. It is easy to design, requires marking only 1 point, and is tension-free, thereby reducing scar widening.

Ruthenium-106 Brachytherapy with or without Additional Local Therapy Shows Favorable Outcome for Variable-Sized Choroidal Melanomas in Korean Patients.

PURPOSE: The purpose of this study was to report clinical outcomes of ruthenium-106 (106Ru) brachytherapy with or without additional local therapy for choroidal melanomas in Korean patients. MATERIALS AND METHODS: A total of 88 patients diagnosed with choroidal melanomas were treated with 106Ru brachytherapy between 2006 and 2012. Patients were divided into two groups according to their tumor height: a large group (≥ 6 mm, n=50) and a small group (< 6 mm, n=38). Most patients in the large group received combined therapy with local excision and/or transpupillary thermotherapy. In general, 85-95 Gy was administered to the apex of the tumor, while 100 Gy was administered to the point 2-6 mm from the outer surface of the sclera for patients undergoing combined therapy. RESULTS: The median follow-up duration was 30 months. The 3-year local control rate was significantly higher in the small group than in the large group (94% vs. 70%, p=0.047). The free from distant metastasis (FFDM) rate and the overall survival (OS) rate were also higher in patients in the small group (3-year FFDM, 97% vs. 76%; p=0.031 and 3-year OS, 97% vs. 72%; p=0.036). A total of 13 patients underwent enucleation. The eye-preservation rate was also higher in the small group (3-year eye-preservation rate, 94% vs. 70%; p=0.050), and tumor height was a significant prognostic factor for eye-preservation. CONCLUSION: 106Ru brachytherapy showed favorable outcomes in small choroidal melanomas in Korean patients. Although additional local treatment could improve eye-preservation rate for large tumors, other strategies should be considered for disease control.

Central pedicle reduction mammaplasty with a vertical scar: a technical modification.

BACKGROUND: This study introduces a central pedicle reduction mammaplasty with a vertical scar technique. OBJECTIVES: This study is aimed to create a more conical breast shape and long-lasting better projection by modifying reduction mammaplasty by central pedicle flap. METHOD: Preoperative markings were made including the meridian line of breast and the new location of the nipple-areola complex (NAC). The new location of the inframammary fold was marked ∼2 ∼ 4 cm above the original inframammary fold. An incision was made around the areola, the area between the resection margins and NAC was excised en bloc. The breast parenchyma was excised circumferentially, so that a cone shaped central mound was formed. An inferior and inferolateral glandular resection was performed to reduce the area of the breast base by elevating the position of the inframammary fold. After completion of dissection, the central pedicle surmounted by the NAC was transposed to its new location. RESULT: Fifty-six patients were operated with our modified central pedicle technique. The mean amount of resection was 475 g (range = 130-1080 g). The mean length of follow-up was 18 months (range = 12-53 months). The mean postoperative satisfaction score was 4.23 (SD = 0.81). The breast parenchymal ratio significantly increased from 1.2 preoperatively to 3.9 postoperatively. CONCLUSION: The modified central pedicle reduction mammaplasty with a vertical scar technique is a versatile breast reduction technique for all shapes and tissue conditions, by providing an attractive conical shape of the breast with minimum scar burden and maximum preservation of breast function.

Arthroscopic detection of medial meniscal injury with the use of a joint distractor in small-breed dogs.

The goal of the present study was to evaluate the diagnostic value of a joint distractor in arthroscopy in small-breed dogs. Sixty stifle joints, which were collected from thirty cadavers, were used in this study. To simulate different injuries, no medial meniscal tear, a full-thickness vertical longitudinal tear, a partial-thickness vertical longitudinal tear, full- and partial-thickness vertical longitudinal tears, or a peripheral detachment were created on the caudal horn of the medial meniscus of each stifle joint along with rupture of the cranial cruciate ligament. Each stifle joint then underwent arthroscopy with and without a joint distractor. The sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), and correct classification rate (CCR) for the diagnosis of each type of medial meniscus pathology were calculated. For arthroscopy with and without a joint distractor, the Sn was 85% and 60%, the Sp was 96% and 92%, the PPV was 85% and 65%, the NPV was 96% and 90%, and the CCR was 94% and 86%, respectively. Arthroscopy is an effective diagnostic method for the assessment of medial meniscal pathologies in small-breed dogs, especially when performed with the aid of a joint distractor.

Improvement of Nasojugal Groove and Wrinkles Following a Skin-Muscle Flap Elevation Through a Subciliary Approach to the Orbital Rim.

The aim of this study is to see whether the nasojugal groove and wrinkles can be improved following a skin-muscle flap elevation through a subciliary approach to the orbital rim.Fifty-seven patients having fractures of the orbital floor, wall, or orbital rim were included. A subciliary incision was made 3 to 5 mm below the cilia. A skin-muscle flap was elevated and a 5-mm width of the periosteum of the anterior surface of the maxilla was exposed. Thereafter, the origin of the orbicularis oculi muscle was released from the underlying bony origin. An incision was made at the arcus marginalis. After reconstruction, the detached arcus marginalis was sutured to the periosteum of the infraorbital rim and the subciliary incision was closed. Preoperative and postoperative photographs were analyzed with the validated assessment scales for midface.In the 57 sides operated on, the postoperative, mean assessment score was significantly lower (0.56 ±â€Š0.66) on the operated side than on the contralateral side (0.84 ±â€Š1.00) (P = 0.002). In the 37 sides excluding the patients in whom the initial score was 0, and the postoperative, mean assessment score was significantly lower (0.84 ±â€Š0.65) on the operated side than on the contralateral side (1.19 ±â€Š1.05) (P = 0.010).The skin-muscle flap elevated through the subciliary approach to reach the orbital rim improved the nasojugal groove despite the fat removal or repositioning was not performed. The reason for this improvement the authors think is orbicularis oculi muscle had been separated from its origin.

Thermoresponsive Polymer and Fluorescent Dye Hybrids for Tunable Multicolor Emission.

Fully reversible emission color change is achieved by blending a thermoresponsive polymer with dye hybrids. The emission color can be tuned by changing the mixing ratio of each polymer-dye hybrid.

Thermo-responsive poly(2-isopropyl-2-oxazoline) and tetraphenylethene hybrids for stimuli-responsive photoluminescence control.

Poly(2-isopropyl-2-oxazoline) (POx), a typical thermo-responsive polymer, was conjugated with a tetraphenylethene derivative, having aggregation induced emission behavior, towards the thermal control of their fluorescence emission. The poly(2-isopropyl-2-oxazoline)-tetraphenylethene hybrids selectively formed a host-guest complex with γ-cyclodextrin. The poly(2-isopropyl-2-oxazoline)-tetraphenylethene hybrids and its host-guest complex with γ-cyclodextrin showed opposite on-off switching of fluorescence emission upon temperature change.

Dendrimer porphyrin-coated gold nanoshells for the synergistic combination of photodynamic and photothermal therapy.

A dendrimer porphyrin (DP)-coated gold nanoshell (AuNS-DP) was prepared for the synergistic combination of photodyanmic and photothermal therapy. The resultant AuNS-DP successfully exhibited the generation of reactive oxygen species (ROS) as well as photothermal effect for the simultaneous application of photodynamic therapy (PDT) and photothermal therapy (PTT).

Skin Necrosis of the Nose After Injection of Ribose Cross-Linked Porcine Atelocollagen.

We report a case of skin necrosis of the nasal tip after an injection of ribose cross-linked porcine atelocollagen (Evolence; Colbar Life Science Ltd, Herzliya, Israel). A 22-year-old woman had a nasal augmentation. From the glabella to the nasal tip, 10 strokes were injected using 0.6 mL of Evolence. On the day of the injection, her nasal tip became cyanotic; a day after it, an erythematous condition developed and a white cheeselike material appeared. On the second day, it became necrotic. Epithelialization was completed for 2 weeks. Despite laser therapy, permanent scarring of the nasal tip was prominent at the 18-month follow-up. It was thought that the skin necrosis is caused by vascular interruption rather than by hypersensitivity because the skin necrosis was confined to the nasal tip. To avoid vascular interruption from a filler injection, aspiration is needed before injection. The least amount of filler should be released in each stroke with low-pressure injection.

Supramolecular coordination polymer formed from artificial light-harvesting dendrimer.

We report the formation of supramolecular coordination polymers formed from multiporphyrin dendrimers (PZnPM; M = FB or Cu), composed of the focal freebase porphyrin (PFB) or cupper porphyrin (PCu) with eight zinc porphyrin (PZn) wings, and multipyridyl porphyrins (PyPM; M = FB or Cu), PFB or PCu with eight pyridyl groups, through multiple axial coordination interactions of pyridyl groups to PZns. UV-vis absorption spectra were recorded upon titration of PyPFB to PZnPFB. Differential spectra, obtained by subtracting the absorption of PZnPFB without guest addition as well as the absorption of PyPFB, exhibited clear isosbestic points with saturation binding at 1 equiv addition of PyPFB to PZnPFB. Job's plot analysis also indicated 1:1 stoichiometry for the saturation binding. The apparent association constant between PZnPFB and PyPFB (2.91 × 10(6) M(-1)), estimated by isothermal titration calorimetry, was high enough for fibrous assemblies to form at micromolar concentrations. The formation of a fibrous assembly from PZnPFB and PyPFB was visualized by atomic force microscopy and transmission electron microscopy (TEM). When a 1:1 mixture solution of PZnPFB and PyPFB (20 µM) in toluene was cast onto mica, fibrous assemblies with regular height (ca. 2 nm) were observed. TEM images obtained from 1:1 mixture solution of PZnPFB and PyPFB (0.1 wt %) in toluene clearly showed the formation of nanofibers with a regular diameter of ca. 6 nm. Fluorescence emission measurement of PZnPM indicated efficient intramolecular energy transfer from PZn to the focal PFB or PCu. By the formation of supramolecular coordination polymers, the intramolecular energy transfer changed to intermolecular energy transfer from PZnPM to PyPM. When the nonfluorescent PyPCu was titrated to fluorescent PZnPFB, fluorescence emission from the focal PFB was gradually decreased. By the titration of fluorescent PyPFB to nonfluorescent PZnPCu, fluorescence emission from PFB in PyPFB was gradually increased due to the efficient energy transfer from PZn wings in PZnPCu to PyPFB.

Effect of Restraining Devices on Facial Fractures in Motor Vehicle Collisions.

The aim of this systematic review is to summarize and critically evaluate the evidence for or against the effectiveness of restraining devices on facial fractures in motor vehicle collisions (MVCs).In a PubMed search, the search terms "facial bone fracture and seat belt," "facial bone fracture and air bag," and "facial bone fracture and restraining" were used. The authors abstracted the odds ratio (OR) and 95% confidence intervals (CIs) from each study. Weighted mean differences and 95% CIs were also calculated. The statistical analysis was performed with Review Manager (The Nordic Cochrane Centre).The authors found 30 potentially relevant articles, of which 6 articles met our inclusion criteria. Five studies were subgrouped, and a meta-analysis of these data suggested beneficial effects of seat belts on decreasing facial fractures in MVCs (n = 15,768,960, OR, 0.46, 95% CI = 0.35-0.60). Three studies were subgrouped, and a meta-analysis of these data suggested that there were beneficial effects of seat belts and air bags on decreasing facial fractures in MVCs (n = 15,768,021, OR, 0.59, 95% CI = 0.47-0.74). Four studies were subgrouped, and a meta-analysis of these data suggested there were no significant effects of an air bag on decreasing facial fracture in MVCs (n = 15,932,259, OR, 1.00, 95% CI = 0.72-1.39).A seat belt alone (OR, 0.46) or a seat belt and an air bag (OR, 0.59) were effective to decrease facial fractures in MVCs. However, air bags alone had no significant effect (OR, 1.00). In using air bags, seat belt should be applied together to prevent facial fractures in motor vehicle injuries.

The Risk of Blepharoptosis in Contact Lens Wearers.

The aim of this systematic review was to summarize and evaluate the risk of blepharoptosis in contact lens wearers. In a PubMed search, 393 papers were found using the terms "lens and ptosis." The abstracts were read and 16 full text articles were reviewed. Among them, 5 articles were analyzed. Five studies were subgrouped and a meta-analysis of these data suggested there is an increased risk of blepharoptosis in hard contact lens wearers over nonwearers (n = 7426, OR, 17.38, 95% CI = 3.71-81.29, P < 0.00001). One study was subgrouped and these data suggested there is also an increased risk of blepharoptosis in soft contact lens wearers over nonwearers (n = 90, OR, 8.12, 95% CI = 2.68-24.87, P < 0.0002). Patients wearing rigid contact lenses should be advised of the risk of ptosis, and a history of contact lens use should be sought in all patients who have acquired ptosis as the previous authors have recommended.