Quality and Agreement With Scientific Consensus of ChatGPT Information Regarding Corneal Transplantation and Fuchs Dystrophy.

PURPOSE: ChatGPT is a commonly used source of information by patients and clinicians. However, it can be prone to error and requires validation. We sought to assess the quality and accuracy of information regarding corneal transplantation and Fuchs dystrophy from 2 iterations of ChatGPT, and whether its answers improve over time. METHODS: A total of 10 corneal specialists collaborated to assess responses of the algorithm to 10 commonly asked questions related to endothelial keratoplasty and Fuchs dystrophy. These questions were asked from both ChatGPT-3.5 and its newer generation, GPT-4. Assessments tested quality, safety, accuracy, and bias of information. Chi-squared, Fisher exact tests, and regression analyses were conducted. RESULTS: We analyzed 180 valid responses. On a 1 (A+) to 5 (F) scale, the average score given by all specialists across questions was 2.5 for ChatGPT-3.5 and 1.4 for GPT-4, a significant improvement (P < 0.0001). Most responses by both ChatGPT-3.5 (61%) and GPT-4 (89%) used correct facts, a proportion that significantly improved across iterations (P < 0.00001). Approximately a third (35%) of responses from ChatGPT-3.5 were considered against the scientific consensus, a notable rate of error that decreased to only 5% of answers from GPT-4 (P < 0.00001). CONCLUSIONS: The quality of responses in ChatGPT significantly improved between versions 3.5 and 4, and the odds of providing information against the scientific consensus decreased. However, the technology is still capable of producing inaccurate statements. Corneal specialists are uniquely positioned to assist users to discern the veracity and application of such information.

Validation of a power law model in upper extremity vessels: potential application in ultrasound bleed detection.

Vascular ultrasound can provide quick and reliable diagnosis of arterial bleeding but it requires trained and experienced personnel. Development of automated sonographic bleed detection methods would potentially be valuable for trauma management in the field. We propose a detection method that (1) measures blood flow in a trauma victim, (2) determines the victim's expected normal limb arterial flow using a power law biofluid model where flow is proportional to the vessel diameter taken to a power of k and (3) quantifies the difference between measured and expected flow with a novel metric, flow split deviation (FSD). FSD was devised to give a quantitative value for the likelihood of arterial bleeding and validated in human upper extremities. We used ultrasound to demonstrate that the power law with k = 2.75 appropriately described the normal brachial artery bifurcation geometry and adequately determined the expected normal flows. Our metric was then applied to three-dimensional (3-D) computational models of forearm bleeding and on dialysis patients undergoing surgical construction of wrist arteriovenous fistulas. Computational models showed that larger sized arterial defects produced larger flow deviations. FSD values were statistically higher (paired t-test) for arms with fistulas than those without, with average FSDs of 0.41 ± 0.12 and 0.047 ± 0.021 (mean ± SD), respectively. The average of the differences was 0.36 ± 0.12 (mean ± SD).

Scleral mechanics: comparing whole globe inflation and uniaxial testing.

The purpose of this study was to assess fundamental differences between the mechanics of the posterior sclera in paired eyes using uniaxial and whole globe inflation testing, with an emphasis on the relationship between testing conditions and observed tissue behavior. Twenty porcine eyes, consisting of matched pairs from 10 pigs, were used in this study. Within pairs, one eye was tested with 10 cycles of globe pressurization to 150 mmHg (∼10× normal IOP) while biaxial strains were tracked via an optical system at the posterior sclera. An excised posterior strip from the second eye was subjected to traditional uniaxial testing in which mechanical hysteresis was recorded from 10 cycles to a peak stress of 0.13 MPa (roughly equivalent to the circumferential wall stress produced by an IOP of 150 mmHg under the thin-walled pressure vessel assumption). For approximately equivalent loads, peak strains were more than twice as high in uniaxial tests than in inflation tests. Different trends in the load-deformation plots were seen between the tests, including an extended "toe" region in the uniaxial test, a generally steeper curve in the inflation tests, and reduced variability in the inflation tests. The unique opportunity of being able to mechanically load a whole globe under near physiologic conditions alongside a standard uniaxially tested specimen reveals the effects of testing artifacts relevant to most uniaxially tested soft tissues. Whole globe inflation offers testing conditions that significantly alter load-deformation behavior relative to uniaxial testing; consequently, laboratory studies of interventions or conditions that alter scleral mechanics may greatly benefit from these findings.

Power law as a method for ultrasound detection of internal bleeding: in vivo rabbit validation.

New detection methods for vascular injuries can augment the usability of an ultrasound (US) imager in trauma settings. The goal of this study was to evaluate a potential-detection strategy for internal bleeding that employs a well-established theoretical biofluid model, the power law. This law characterizes normal blood-flow rates through an arterial tree by its bifurcation geometry. By detecting flows that deviate from the model, we hypothesized that vascular abnormalities could be localized. We devised a bleed metric, flow-split deviation (FSD), that quantified the difference between patient and model blood flows at vessel bifurcations. Femoral bleeds were introduced into ten rabbits (∼5 kg) using a cannula attached to a variable pump. Different bleed rates (0% as control, 5%, 10%, 15%, 20%, 25%, and 30% of descending aortic flow) were created at two physiological states (rest and elevated state with epinephrine). FSDs were found by US imaging the iliac arteries. Our bleed metric demonstrated good sensitivity and specificity at moderate bleed rates; area under receiver-operating characteristic curves were greater than 0.95 for bleed rates 20% and higher. Thus, FSD was a good indicator of bleed severity and may serve as an additional tool in the US bleed detection.

Microenvironment regulation of extracellular signal-regulated kinase activity in chondrocytes: effects of culture configuration, interleukin-1, and compressive stress.

OBJECTIVE: To compare extracellular signal-regulated kinase (ERK) activity in response to interleukin-1 (IL-1) in chondrocytes under various culture configurations designed for the study of cartilage biology and repair, and also in response to dynamic load for chondrocytes in cartilage. METHODS: Isolated bovine articular chondrocytes were maintained in serum-supplemented medium under 4 culture configurations: high-density monolayer, attached to a cut surface of cartilage, within tissue-engineered constructs, or within intact cartilage explants. Samples were subjected to a change of medium with or without IL-1. Cartilage explants were also subjected to dynamic compression. RESULTS: In chondrocyte monolayers, both basal and IL-1-stimulated ERK activities were similarly elevated at 0.5 hours after medium change, diminishing by 74% after 16 hours. In contrast, chondrocytes in other culture configurations exhibited lower basal levels of ERK activity and a moderate activation of ERK in response to IL-1 that was sustained over the 16-hour treatment time. The dynamic component of loading of cartilage explants led to a 5-fold activation of ERK, compared with free-swelling controls, that was indistinguishable from the effects of IL-1. CONCLUSION: ERK signaling in response to IL-1 in chondrocyte monolayers exhibited a pattern that was distinct from that in other culture systems, suggesting that the extracellular matrix plays an important regulatory role in modulating the response to extracellular stimuli. Since IL-1 and dynamic loading have distinct effects on chondrocyte biosynthesis, signaling pathways other than ERK participate in the chondrocyte responses to these stimuli.