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1.
J Clin Neurosci ; 121: 83-88, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38368659

RESUMEN

INTRODUCTION: Permanent liquor diversion is associated with a high risk of failure and often requires re-intervention. The ventriculo-gallbladder shunt (VGS) has been recognized as a last-resort alternative for treating hydrocephalus when the peritoneum or other distal sites are no longer suitable for receiving shunts. This article aims to report a case from a neurosurgery referral service in Brazil and review the literature on this issue. METHODS: A systematic literature review was conducted in accordance with the PRISMA statement. The PubMed, Embase, and Web of Science databases were searched for data screening and extraction. The reported case was conducted with ethical approval from the neurosurgical hospital's ethics committee. RESULTS: G.B.S, male, 43 years old, no comorbidities, who has been dealing with a 12-year history of hydrocephalus, with post-surgical chronic fungal meningitis. Two years ago, he underwent a ventriculoatrial shunt (VAS) placement due to multiple ventriculoperitoneal shunt (VPS) failures. Endocarditis was suspected, and the VAS was removed. As an alternative, VGS was implanted 6 months ago, and since then, there has been no need for a new system review. The gallbladder has an absorptive capacity of 1500 cc of liquid daily, which is more than the normal daily production of cerebrospinal fluid (CSF). Therefore, it is a good alternative when the ventriculoperitoneal shunt is not feasible due to postsurgical peritoneal adhesions or when there are contraindications for ventriculoatrial shunts. CONCLUSION: VGS is an alternative for patients who cannot undergo the most common surgical interventions, such as VPS.


Asunto(s)
Derivaciones del Líquido Cefalorraquídeo , Hidrocefalia , Adulto , Humanos , Masculino , Vesícula Biliar/cirugía , Hidrocefalia/cirugía , Hidrocefalia/complicaciones , Prótesis e Implantes , Derivación Ventriculoperitoneal/efectos adversos
2.
Bioengineering (Basel) ; 11(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38391634

RESUMEN

PURPOSE: To investigate corneal densitometry artefacts found in Pentacam Scheimpflug scans and their potential effect on assessing keratoconic (KC) corneas compared to normal (N) corneas. METHODS: The current study utilises Pentacam data of 458 N eyes, aged 35.6 ± 15.8 (range 10-87), referred to as the "N group", and 314 KC eyes, aged 31.6 ± 10.8 (range 10-72), referred to as the "KC group", where densitometry data were extracted and analysed via a custom-built MATLAB code. Radial summations of the densitometry were calculated at diameters ranging from 0.5 mm to 5.0 mm. The minimum normalised radial summation of densitometry (NRSD) value and angle were determined at each diameter and then linked. KC cone locations and areas of pathology were determined, and a comparison between N and KC groups was carried out both within the averaged area of pathology and over the corneal surface. RESULTS: Joining minimum NRSD trajectory points marked a clear distortion line pointing to the nasal-superior direction at 65° from the nasal meridian. The findings were found to be independent of eye laterality or ocular condition. Consistency was detected in the right and left eyes among both the N and KC groups. The location of the KC cone centre and the area of pathology were determined, and the densitometry output was compared both within the area of pathology and over the whole cornea. When the average densitometry was compared between N and KC eyes within the KC area of pathology, the N group recorded a 16.37 ± 3.15 normalised grey-scale unit (NGSU), and the KC group recorded 17.74 ± 3.4 NGSU (p = 0.0001). However, when the whole cornea was considered, the N group recorded 16.71 ± 5.5 NGSU, and the KC group recorded 15.72 ± 3.98 NGSU (p = 0.0467). A weak correlation was found between the Bad D index and NGSU when the whole measured cornea was considered (R = -0.01); however, a better correlation was recorded within the KC area of pathology (R = 0.21). CONCLUSIONS: Nasal-superior artefacts are observed in the densitometry Pentacam maps, and analysis shows no significant differences in their appearance between N or KC corneas. When analysing KC corneas, it was found that the cone positions are mostly on the temporal-inferior side of the cornea, opposite to the densitometry artefact NRSD trajectory. The analysis suggests that the corneal densitometry artefacts do not interfere with the KC area of pathology as it reaches its extreme in the opposite direction; therefore, weighting the densitometry map to increase the contribution of the inferior-temporal cornea and decreasing that of the superior-nasal area would improve the classification or identification of KC if densitometry is to be used as a KC metric.

3.
World Neurosurg ; 184: e708-e719, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38340795

RESUMEN

OBJECTIVE: To assess the efficacy and surgical outcomes of the simultaneous single-trajectory endoscopic biopsy and third ventriculostomy (ETV) in pineal region tumors. METHODS: A systematic review and meta-analysis adhering to Cochrane Standards and PRISMA framework were conducted. PubMed, Embase, and Web Of Science databases were searched until December 2023. Outcomes included rate of histopathologic diagnosis success, ETV success, complications, required VPS, and mortality. RESULTS: Seventeen studies (N = 388) met inclusion criteria. Histopathologic diagnosis success rate was 90% for general population (95% CI: 86%-95%; I2 = 42%) and 94% for pediatric patients (95% CI: 89%-98%; I2 = 19%). ETV Success rate was 93% (95% CI: 88%-97%; I2 = 60%). An estimated risk of postoperative ETV complications was found to be 16% for the general population (95% CI: 5%-28%; I2 = 90%) and 5% for pediatric patients (95% CI: 0%-13%; I2 = 51%). The risk of requiring VPS was estimated as 2% (95% CI: 0%-4%; I2 = 39%) and for the pediatric population it was 7% (95% CI: 0%-16%; I2 = 69%). Mortality risk was found to be 1% (95% CI: 0%-3%; I2 = 0%). CONCLUSIONS: Simultaneous endoscopic biopsy and ETV demonstrated high diagnostic and therapeutic success rates. The procedure's safety profile, with low mortality and complications, supports its role in treating hydrocephalus associated to pineal region tumors. Subgroup analyses revealed higher diagnostic success rates and required VPS in the pediatric population, whilst it had lower complication rates.


Asunto(s)
Neoplasias Encefálicas , Hidrocefalia , Neuroendoscopía , Glándula Pineal , Pinealoma , Tercer Ventrículo , Niño , Humanos , Ventriculostomía/efectos adversos , Neuroendoscopía/efectos adversos , Tercer Ventrículo/cirugía , Pinealoma/cirugía , Pinealoma/complicaciones , Biopsia/efectos adversos , Complicaciones Posoperatorias/epidemiología , Hidrocefalia/cirugía , Hidrocefalia/etiología , Neoplasias Encefálicas/cirugía , Neoplasias Encefálicas/complicaciones , Glándula Pineal/cirugía , Resultado del Tratamiento , Estudios Retrospectivos
4.
Eye Vis (Lond) ; 10(1): 45, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37919821

RESUMEN

Different diagnostic approaches for ectatic corneal diseases (ECD) include screening, diagnosis confirmation, classification of the ECD type, severity staging, prognostic evaluation, and clinical follow-up. The comprehensive assessment must start with a directed clinical history. However, multimodal imaging tools, including Placido-disk topography, Scheimpflug three-dimensional (3D) tomography, corneal biomechanical evaluations, and layered (or segmental) tomography with epithelial thickness by optical coherence tomography (OCT), or digital very high-frequency ultrasound (dVHF-US) serve as fundamental complementary exams for measuring different characteristics of the cornea. Also, ocular wavefront analysis, axial length measurements, corneal specular or confocal microscopy, and genetic or molecular biology tests are relevant for clinical decisions. Artificial intelligence enhances interpretation and enables combining such a plethora of data, boosting accuracy and facilitating clinical decisions. The applications of diagnostic information for individualized treatments became relevant concerning the therapeutic refractive procedures that emerged as alternatives to keratoplasty. The first paradigm shift concerns the surgical management of patients with ECD with different techniques, such as crosslinking and intrastromal corneal ring segments. A second paradigm shift involved the quest for identifying patients at higher risk of progressive iatrogenic ectasia after elective refractive corrections on the cornea. Beyond augmenting the sensitivity to detect very mild (subclinical or fruste) forms of ECD, ectasia risk assessment evolved to characterize the inherent susceptibility for ectasia development and progression. Furthermore, ectasia risk is also related to environmental factors, including eye rubbing and the relational impact of the surgical procedure on the cornea.

5.
Int Ophthalmol ; 43(11): 4289-4295, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37644351

RESUMEN

PURPOSE: The Corvis Biomechanical Index-Laser Vision Correction (CBI-LVC) is a biomechanical index to detect ectasia in post-refractive surgery patients (PRK, LASIK, SMILE). This study aims to evaluate the distribution of the CBI-LVC in stable patients who underwent Phototherapeutic Keratectomy (PTK) compared to PRK patients. METHODS: Patients who underwent PRK and PTK performed between 2000 and 2018 in Humanitas Research Hospital, Rozzano, Milan, Italy and remained stable for at least four years post-surgery were included. All eyes were examined with the Corvis ST (Oculus, Germany), whose output allows the calculation of the CBI-LVC. The distribution and specificity of the CBI-LVC in the two populations were estimated using a Wilcoxon Mann-Whitney test and compared. RESULTS: 175 eyes of 148 patients were included (85 eyes of 50 PTK patients and 90 eyes of 90 PRK patients). The distribution of CBI-LVC in the two groups showed a minor difference, with a median value in PRK patients of 0.000 (95% CI 0.000; 0.002) and 0.008 (95% CI 0.000; 0.037) in PTK patients (Mann-Whitney U test p = 0.023). The statistical analysis showed that the CBI-LVC provided a specificity of 92.22% in the PRK group, while in the PTK group it was 82.35%. Nevertheless, this difference was not statistically significant (Chi-squared test with Yates, p = 0.080). CONCLUSION: CBI-LVC provided similar specificity in stable PTK patients compared to those who underwent PRK. These results suggest that the CBI-LVC could be a useful tool to aid corneal surgeons in managing PTK patients.


Asunto(s)
Queratomileusis por Láser In Situ , Queratectomía Fotorrefractiva , Cirujanos , Humanos , Córnea/cirugía , Rayos Láser
6.
Curr Eye Res ; 48(4): 382-391, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36581595

RESUMEN

PURPOSE: To improve the stability of the Corvis ST biomechanically-corrected intraocular pressure measurements (bIOP) after refractive surgery and its independence of corneal biomechanics. METHODS: A parametric study was carried out using numerical models simulating the behavior of the eye globe under the effects of IOP and Corvis ST external air pressure and used to develop a new algorithm for bIOP; bIOP(v2). It was tested on 528 healthy participants to evaluate correlations with CCT and age. Its ability to compensate for the geometrical changes was tested in 60 LASIK and 80 SMILE patients with six months follow up. The uncorrected Corvis ST IOP (CVS-IOP) and the two versions of biomechanically corrected IOP; bIOP(v1) and bIOP(v2), were compared. RESULTS: In the healthy dataset, bIOP(v2) had weak and non-significant correlation with both CCT (R = -0.048, p = .266) and age (R = 0.085, p = .052). For bIOP(v1), the correlation was non-significant with CCT (R = -0.064, p = .139) but significant with age (R = -0.124, p < .05). In both LASIK and SMILE groups, the median change in bIOP(v2) following surgery was below 1 mmHg at follow-up stages and the interquartile range was smaller than both bIOP(v1) and CVS-IOP. CONCLUSION: The bIOP(v2) algorithm performs better than bIOP(v1) and CVS-IOP in terms of correlation with CCT and age. The bIOP(v2) also demonstrated the smallest variation after LASIK and SMILE refractive surgeries indicating improved ability to compensate for geometrical changes.


Asunto(s)
Glaucoma de Ángulo Abierto , Queratomileusis por Láser In Situ , Humanos , Presión Intraocular , Tonometría Ocular , Córnea , Fenómenos Biomecánicos
7.
Curr Eye Res ; 48(2): 130-136, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35184637

RESUMEN

Purpose: To prospectively review the importance of biomechanical assessment in the screening, diagnosis, prognosis, individualized planning, and clinical follow-up for ectatic corneal diseases.Methods: We demonstrate two commercially available devices to assess the corneal biomechanics in vivo, the Ocular Response Analyzer (ORA, Reichester, NY, USA) and the Corvis ST (Oculus, Wetzlar, Germany). Novel devices have been demonstrated to provide in vivo biomechanical measurements, including Brillouin optical microscopy and OCT elastography. Conclusion: The integration of biomechanical data and other data from multimodal refractive imaging using artificial intelligence demonstrated the ability to enhance accuracy in diagnosing ectatic corneal diseases.


Asunto(s)
Queratocono , Humanos , Queratocono/diagnóstico , Fenómenos Biomecánicos , Inteligencia Artificial , Elasticidad , Córnea , Dilatación Patológica
8.
Curr Eye Res ; 48(2): 114-120, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35634717

RESUMEN

The study of corneal stiffness in vivo has numerous clinical applications such as the measurement of intraocular pressure, the preoperative screening for iatrogenic ectasia after laser vision correction surgery and the diagnosis and treatment of corneal ectatic diseases such as keratoconus. The localised aspect of the microstructure deterioration in keratoconus leading to local biomechanical softening, corneal bulging, irregular astigmatism and ultimately loss of vision boosted the need to map the corneal stiffness to identify the regional biomechanical failure. Currently, two methods to map the corneal stiffness in vivo are integrated into devices that are either already commercially available or about to be commercialised: the stress-strain index (SSI) maps and the Brillouin Microscopy (BM). The former method produces 2D map of stiffness across the corneal surface, developed through numerical simulations using the corneal shape, its microstructure content, and the deformation behaviour under air-puff excitation. It estimates the whole stress-strain behaviour, making it possible to obtain the material tangent modulus under different intraocular pressure levels. On the other hand, BM produces a 3D map of the corneal longitudinal modulus across the corneal surface and thickness. It uses a low-power near-infrared laser beam and through a spectral analysis of the returned signal, it assesses the mechanical compressibility of the tissue as measured by the longitudinal modulus. In this paper, these two techniques are reviewed, and their advantages and limitations discussed.


Asunto(s)
Queratocono , Humanos , Queratocono/diagnóstico , Queratocono/cirugía , Microscopía , Fenómenos Biomecánicos , Córnea , Presión Intraocular
9.
Curr Eye Res ; 48(2): 137-143, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36001080

RESUMEN

Recent advances, specifically in the understanding of the biomechanical properties of the cornea and its response to diseases and surgical interventions, have significantly improved the safety and surgical outcomes of corneal refractive surgery, whose popularity and demand continue to grow worldwide. However, iatrogenic keratectasia resulting from the deterioration in corneal biomechanics caused by surgical interventions, although rare, remains a global concern. On one hand, in vivo biomechanical evaluation, enabled by clinical imaging systems such as the ORA and the Corvis ST, has significantly improved the risk profiling of patients for iatrogenic keratectasia. That is despite the fact the biomechanical metrics provided by these systems are considered indicators of the cornea's overall stiffness rather than its intrinsic material properties. On the other hand, new surgical modalities including SMILE were introduced to offer superior biomechanical performance to LASIK, but this superiority could not be proven clinically, creating more myths than answers. The literature also includes sound evidence that tPRK provided the highest preservation of corneal biomechanics when compared to both LASIK and SMILE. The aim of this review is twofold; to discuss the importance of corneal biomechanical evaluation prior to refractive surgery, and to assess the current understanding of cornea's biomechanical deterioration caused by mainstream corneal refractive surgeries. The review has led to an observation that new imaging techniques, parameters and evaluation systems may be needed to reflect the true advantages of specific refractive techniques and when these advantages are significant enough to offer better protection against post-surgery complications.


Asunto(s)
Queratomileusis por Láser In Situ , Miopía , Humanos , Fenómenos Biomecánicos , Agudeza Visual , Miopía/cirugía , Córnea/cirugía , Córnea/fisiología , Queratomileusis por Láser In Situ/métodos , Enfermedad Iatrogénica
10.
J Cataract Refract Surg ; 49(2): 190-194, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36201664

RESUMEN

PURPOSE: To test the ability of the corneal epithelial pattern standard deviation (PSD) to distinguish between normal and cases with corneal ectatic condition. SETTING: Instituto de Olhos Renato Ambrósio, Rio de Janeiro, Brazil. DESIGN: Cross-sectional retrospective study. METHODS: Patients were stratified into 4 groups based on clinical data and corneal tomography. Groups 1 and 2 comprised 1 eye randomly selected from 105 patients with normal corneas (N) and 86 patients with bilateral keratoconus (KC). Groups 3 and 4, respectively, comprised 11 ectatic eyes with no surgical treatment for KC (very asymmetric ectasia [VAE]-E) from patients whose fellow eyes (61) presented with normal topographic patterns (VAE-NT). Corneas were scanned using an OCT system (RT Vue) and Scheimpflug corneal tomography (Pentacam) and also had biomechanical assessment through the Corvis ST. Corneal epithelial thickness maps were analyzed, and the PSD value was calculated. The area under the receiver operating characteristic curve analysis was used to evaluate the diagnostic accuracy of the indices. RESULTS: A total of 105 normal eyes, 86 keratoconic eyes, and 11 ectatic eyes whose fellow eyes (61) presented normal topographic patterns were evaluated. Epithelial PSD was significantly different across the 4 groups ( P < .0001). The pairwise comparison revealed that the normal group presented significantly lower values than both ectasia groups (KC and VAE-E, P < .0001) and the VAE-NT group ( P = .0008). There was no statistical significant difference between KC and VAE-E ( P = .4284), while they were significantly higher than the VAE-NT group ( P < .0001 and P = .0004). CONCLUSIONS: Epithelial PSD can be used to detect abnormal epithelial thickness patterns. Corneal epithelial thickness changes could be detected accurately in patients with KC, even in the form fruste of the disease.


Asunto(s)
Queratocono , Humanos , Estudios Retrospectivos , Queratocono/diagnóstico , Topografía de la Córnea/métodos , Tomografía de Coherencia Óptica , Paquimetría Corneal , Dilatación Patológica/diagnóstico , Estudios Transversales , Brasil , Córnea , Curva ROC
11.
Rev. bras. oftalmol ; 82: e0029, 2023. graf
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1449768

RESUMEN

RESUMO Objetivo Avaliar a precisão da tomografia corneana com imagens de Scheimpflug (Pentacam® AXL, OCULUS, Wetzlar, Alemanha) nos padrões de escaneamento com 25 e 50 imagens, verificando sua repetibilidade e reprodutibilidade em olhos normais, com ceratocone e com ceratocone após crosslinking. Métodos Estudo prospectivo, transversal, misto, no qual foram incluídos os pacientes que tinham córneas normais, ou com ceratocone; e não tinham realizado cirurgias corneanas, com exceção do crosslinking. Foram excluídos os pacientes que tivessem realizado outras cirurgias, como implante de anel intracorneano ou transplante de córnea. Foram realizadas três medidas com 25 imagens e três medidas com 50 imagens em cada olho incluído no estudo. Resultados O estudo avaliou 54 olhos de 41 pacientes. Destes, dez (18,52%) olhos eram com córneas normais e sem cirurgia ocular prévia aleatoriamente selecionados de 5 pacientes; 22 (40,74%) olhos aleatoriamente selecionados de 18 pacientes com ceratocone, sem cirurgia ocular prévia; e 22 (40,74%) olhos com ceratocone de 18 pacientes operados por crosslinking. No estudo da repetibilidade, percebemos uma maior variação de valores em todos os índices nos pacientes com ceratocone comparados aos de pacientes com olhos normais, em grande parte dos parâmetros analisados. Conclusão Não houve diferença significativa entre os métodos de escaneamento por 25 e 50 imagens, sendo o escaneamento por 25 imagens mais conveniente. A presença de ceratocone teve impacto negativo na repetibilidade de ambos os tipos de exame, e foi grande a concordância entre os métodos nos três grupos estudados. O coeficiente de repetibilidade permite considerar a relevância clínica dos dados para avaliar a progressão de ceratocone.


ABSTRACT Objective To evaluate the accuracy of corneal tomography with Scheimpflug images (Pentacam® AXL, OCULUS, Wetzlar, Germany) in scanning patterns with 25 and 50 images, by analyzing their repeatability and reproducibility in normal eyes, eyes with keratoconus and with keratoconus after crosslinking. Methods Prospective, cross-sectional, mixed study including patients who had normal corneas, or who had keratoconus, who had not undergone corneal surgery, with the exception of crosslinking. Patients who had undergone surgery for intracorneal ring implantation or corneal transplantation were excluded. Three measurements were performed with 25 images and three measurements were performed with 50 images on each eye included in the study. Results The study evaluated a total of 54 eyes of 41 patients. Of these, 10 (18.52%) eyes had normal corneas, without previous eye surgery, 22 (40.74%) were eyes with keratoconus, without previous eye surgery, and 22 (40.74%) were eyes with keratoconus, with crosslinking for keratoconus. In the study of repeatability, we noticed a greater variation of values in all indices in patients with KC compared to those with normal eyes, in most of the parameters analyzed. Conclusion There is no significant difference between the scanning methods with 25 and 50 images. However, 25 scans has advantages that make it the main method suggested. The presence of keratoconus has a negative impact on the repeatability of both types of examination, and there is great agreement between the methods in the three groups studied. The high repeatability coefficient in some parameters suggests that these data should be used with care in the assessment of keratoconus progression.

12.
Diagnostics (Basel) ; 12(12)2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36553038

RESUMEN

There are different fundamental diagnostic strategies for patients with ectatic corneal diseases (ECDs): screening, confirmation of the diagnosis, classification of the type of ECD, severity staging, prognostic assessment, and clinical follow-up. The conscious application of such strategies enables individualized treatments. The need for improved diagnostics of ECD is related to the advent of therapeutic refractive procedures that are considered prior to keratoplasty. Among such less invasive procedures, we include corneal crosslinking, customized ablations, and intracorneal ring segment implantation. Besides the paradigm shift in managing patients with ECD, enhancing the sensitivity to detect very mild forms of disease, and characterizing the inherent susceptibility for ectasia progression, became relevant for identifying patients at higher risk for progressive iatrogenic ectasia after laser vision correction (LVC). Moreover, the hypothesis that mild keratoconus is a risk factor for delivering a baby with Down's syndrome potentially augments the relevance of the diagnostics of ECD. Multimodal refractive imaging involves different technologies, including Placido-disk corneal topography, Scheimpflug 3-D tomography, segmental or layered tomography with layered epithelial thickness using OCT (optical coherence tomography), and digital very high-frequency ultrasound (VHF-US), and ocular wavefront. Corneal biomechanical assessments and genetic and molecular biology tests have translated to clinical measurements. Artificial intelligence allows for the integration of a plethora of clinical data and has proven its relevance in facilitating clinical decisions, allowing personalized or individualized treatments.

13.
Heliyon ; 8(11): e11699, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36468117

RESUMEN

Purpose: To investigate the relationship between Ortho-K contact lens design parameters and refractive power change of the eye through a parametric mathematical representation. Methods: The current study utilises fully anonymized records of 249 eyes, 132 right eyes, and 117 left eyes from subjects aged 14.1 ± 4.0 years on average (range 9-38 years) which were selected for secondary analysis processing. The data were split into 3 groups (G1 up to 35 days wear, from 10 to 35 days, G2 up to 99 days wear, more than 35-99 days & G3 more than 100 days wear) according to the length of time, in days, that the lenses were worn. Corneal shape was measured before and after contact lens wear using the Medmont E300 topographer, from which height and distance files were read by a custom-built MATLAB code to construct the corneal anterior surface independently. Changes in refractive power pre and post-Ortho-K wear were determined using constructed tangential refractive power maps from which both centrally flattened and annular steepened zones were automatically bounded, hence used to determine the refractive power change. Results: On average, flat Sim-K and steep Sim-K were reduced after Ortho-K lens wear by 1.6 ± 1.3 D and 1.3 ± 1.4 D respectively. The radius of the base curve was correlated with the mean central flattened zone power change strongly in G1 (R = 0.7, p < 0.001) and moderately in G2 (R = 0.4) and G3 (R = 0.4, p < 0.001). Hence, a strong correlation with the base curve was recorded in group G1 and moderate in G2 and G3. The reverse curve was very strongly correlated to the mean central flattened zone power change in G1 (R = 0.8, p < 0.001) and strongly correlated with G2 (R = 0.6, p < 0.001) and G3 (R = 0.7, p < 0.001). The reverse curve was also strongly correlated with the mean annular steepened zone power change among all groups G1, G2, and G3 (R = 0.7, R = 0.6 and R = 0.6) respectively (p < 0.001). Conclusions: Although the central corneal refractive power change was strongly correlated to the Ortho-K lens base curve, it characterized only 50% of the target power change. However, the annular steepened zone refractive power change appears to be a clearer predictor of target power change, as there appears to be a one-to-one inverse relationship with the target refractive power correction. Differences between these results and the literature may be a result of the topography software smoothing effect.

14.
J Cardiovasc Comput Tomogr ; 16(6): 524-530, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35872136

RESUMEN

BACKGROUND: New permanent pacemaker implantation (new-PPI) remains a compelling issue after Transcatheter Aortic Valve Replacement (TAVR). Previous studies reported the relationship between a short MS length and the new-PPI post-TAVR with a self-expanding THV. However, this relationship has not been investigated in different currently available THV. Therefore, the aim of this study was to investigate the association between membranous septum (MS)-length and new-PPI after TAVR with different Transcatheter Heart Valve (THV)-platforms. METHODS: We included patients with a successful TAVR-procedure and an analyzable pre-procedural multi-slice computed tomography. MS-length was measured using a standardized methodology. The primary endpoint was the need for new-PPI within 30 days after TAVR. RESULTS: In total, 1811 patients were enrolled (median age 81.9 years [IQR 77.2-85.4], 54% male). PPI was required in 275 patients (15.2%) and included respectively 14.2%, 20.7% and 6.3% for Sapien3, Evolut and ACURATE-THV(p â€‹< â€‹0.01). Median MS-length was significantly shorter in patients with a new-PPI (3.7 â€‹mm [IQR 2.2-5.1] vs. 4.1 â€‹mm [IQR 2.8-6.0], p â€‹= â€‹<0.01). Shorter MS-length was a predictor for PPI in patients receiving a Sapien3 (OR 0.87 [95% CI 0.79-0.96], p â€‹= â€‹<0.01) and an Evolut-THV (OR 0.91 [95% CI 0.84-0.98], p â€‹= â€‹0.03), but not for an ACURATE-THV (OR 0.99 [95% CI 0.79-1.21], p â€‹= â€‹0.91). By multivariable analysis, first-degree atrioventricular-block (OR 2.01 [95% CI 1.35-3.00], p = <0.01), right bundle branch block (OR 8.33 [95% CI 5.21-13.33], p = <0.01), short MS-length (OR 0.89 [95% CI 0.83-0.97], p â€‹< â€‹0.01), annulus area (OR 1.003 [95% CI 1.001-1.005], p â€‹= â€‹0.04), NCC implantation depth (OR 1.13 [95% CI 1.07-1.19] and use of Evolut-THV(OR 1.54 [95% CI 1.03-2.27], p â€‹= â€‹0.04) were associated with new-PPI. CONCLUSION: MS length was an independent predictor for PPI across different THV platforms, except for the ACURATE-THV. Based on our study observations within the total cohort, we identified 3 risk groups by MS length: MS length ≤3 â€‹mm defined a high-risk group for PPI (>20%), MS length 3-7 â€‹mm intermediate risk for PPI (10-20%) and MS length > 7 â€‹mm defined a low risk for PPI (<10%). Anatomy-tailored-THV-selection may mitigate the need for new-PPI in patients undergoing TAVR.


Asunto(s)
Estenosis de la Válvula Aórtica , Prótesis Valvulares Cardíacas , Marcapaso Artificial , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Masculino , Anciano de 80 o más Años , Femenino , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Factores de Riesgo , Resultado del Tratamiento , Valor Predictivo de las Pruebas , Sistema de Registros , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Diseño de Prótesis
15.
JAMA Cardiol ; 7(9): 924-933, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35857306

RESUMEN

Importance: Chronic aortic regurgitation (AR) causes left ventricular (LV) volume overload, which results in progressive LV remodeling negatively affecting outcomes. Whether cardiac magnetic resonance (CMR) volumetric quantification can provide incremental risk stratification over standard clinical and echocardiographic evaluation in patients with chronic moderate or severe AR is unknown. Objective: To compare LV remodeling measurements by CMR and echocardiography between patients with and without heart failure symptoms and to verify the association of remodeling measurements of patients with chronic moderate or severe AR but no or minimal symptoms with clinical outcomes receiving medical management. Design, Setting, and Participants: This multicenter retrospective cohort study included consecutive patients with at least moderate chronic native AR evaluated by 2-dimensional transthoracic echocardiography and CMR examination within 90 days from each other between January 2012 and February 2020 at Allina Health System. Data were analyzed from June 2021 to January 2022. Exposures: Clinical evaluation and risk stratification by CMR. Main Outcomes and Measures: The end point was a composite of death, heart failure hospitalization, or progression of New York Heart Association functional class while receiving medical management, censoring patients at the time of aortic valve replacement (when performed) or at the end of follow-up. Results: Of the 178 included patients, 119 (66.9%) were male, 158 (88.8%) presented with no or minimal symptoms (New York Heart Association class I or II), and the median (IQR) age was 58 (44-69) years. Compared with patients with no or minimal symptoms, symptomatic patients had greater LV end-systolic volume index (LVESVi) by CMR (median [IQR], 66 [46-85] mL/m2 vs 42 [30-58] mL/m2; P < .001), while there were no significant differences by echocardiography (LVESVi: median [IQR], 38 [30-58] mL/m2 vs 27 [20-42] mL/m2; P = .07; LV end-systolic diameter index: median [IQR], 21 [17-25] mm/m2 vs 18 [15-22] mm/m2; P = .17). During the median (IQR) follow-up of 3.3 (1.6-5.8) years, 50 patients with no or minimal symptoms receiving medical management developed the composite end point, which, in multivariate analysis adjusted for age and EuroSCORE II, was independently associated with LVESVi of 45 mL/m2 or greater and aortic regurgitant fraction of 32% or greater, the latter adding incremental prognostic value to CMR volumetric assessment. Conclusions and Relevance: In patients with chronic moderate or severe AR, patients presenting with heart failure symptoms have greater LVESVi by CMR than those with no or minimal symptoms. In patients with no or minimal symptoms, CMR quantification of LVESVi and AR severity may identify those at risk of death or incident heart failure and therefore should be considered in the clinical evaluation and decision-making of these patients.


Asunto(s)
Insuficiencia de la Válvula Aórtica , Insuficiencia Cardíaca , Anciano , Válvula Aórtica/cirugía , Insuficiencia de la Válvula Aórtica/cirugía , Femenino , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Remodelación Ventricular
16.
Front Bioeng Biotechnol ; 10: 812507, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35757796

RESUMEN

Purpose: To evaluate the regional corneal biomechanical deterioration with keratoconus (KC) progression as measured by the Stress-Strain Index (SSI) maps. Methods: The preoperative examinations of 29 progressive KC cases that were submitted to corneal cross-linking (CXL) were evaluated. The examinations included the tomography and the SSI measured by the Pentacam HR and the Corvis ST (Oculus, Wetzlar, Germany), respectively. The results were recorded twice, the latter of which was at the last visit before the CXL procedure. The patient-specific SSI maps were built, using data at each examination, based on finite element modelling and employing inverse analysis to represent the regional variation of biomechanical stiffness across the cornea. Results: All cases presented significant shape progression (above the 95% CI of repeatability) in anterior and posterior curvatures and minimum thickness. The overall corneal stiffness as measured by the SSI within the central 8 mm-diameter area underwent slight but significant reductions from the first to the last examination (-0.02 ± 0.02, range: -0.09 to 0, p < 0.001). In all 29 cases, the reduction in stiffness was localised and concentred in the area inside the keratoconus cone. The SSI values inside the cone were significantly lower in the last examination (by 0.15 ± 0.09, range: -0.42 to -0.01, p < 0.001), while the SSI outside the cone presented minimal, non-significant variations (0 ± 0.01, range: -0.04 to 0.01, p = 0.999). Conclusion: It has been observed through the SSI maps that the regional deterioration in stiffness was concerted inside the area of pathology, while only mild non-significant alterations were observed outside the area of pathology.

17.
Arq Bras Cardiol ; 118(4): 756-765, 2022 04.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-35508053

RESUMEN

BACKGROUND: It has recently been demonstrated that the application of high-energy ultrasound and microbubbles, in a technique known as sonothrombolysis, dissolves intravascular thrombi and increases the angiographic recanalization rate in patients with ST-segment-elevation myocardial infarction (STEMI). OBJECTIVE: To evaluate the effects of sonothrombolysis on left ventricular wall motion and myocardial perfusion in patients with STEMI, using real-time myocardial perfusion echocardiography (RTMPE). METHODS: One hundred patients with STEMI were randomized into the following 2 groups: therapy (50 patients treated with sonothrombolysis and primary coronary angioplasty) and control (50 patients treated with primary coronary angioplasty). The patients underwent RTMPE for analysis of left ventricular ejection fraction (LVEF), wall motion score index (WMSI), and number of segments with myocardial perfusion defects 72 hours after STEMI and at 6 months of follow-up. P < 0.05 was considered statistically significant. RESULTS: Patients treated with sonothrombolysis had higher LVEF than the control group at 72 hours (50% ± 10% versus 44% ± 10%; p = 0.006), and this difference was maintained at 6 months of follow-up (53% ± 10% versus 48% ± 12%; p = 0.008). The WMSI was similar in the therapy and control groups at 72 hours (1.62 ± 0.39 versus 1.75 ± 0.40; p = 0.09), but it was lower in the therapy group at 6 months (1.46 ± 0.36 versus 1.64 ± 0.44; p = 0.02). The number of segments with perfusion defects on RTMPE was similar in therapy and control group at 72 hours (5.92 ± 3.47 versus 6.94 ± 3.39; p = 0.15), but it was lower in the therapy group at 6 months (4.64 ± 3.31 versus 6.57 ± 4.29; p = 0.01). CONCLUSION: Sonothrombolysis in patients with STEMI resulted in improved wall motion and ventricular perfusion scores over time.


FUNDAMENTO: Demonstrou-se recentemente que a aplicação de ultrassom de alta energia com microbolhas, técnica conhecida como sonotrombólise, causa a dissolução de trombos intravasculares e aumenta a taxa de recanalização angiográfica no infarto agudo do miocárdio com supradesnivelamento do segmento ST (IAM-CSST). OBJETIVO: Avaliar o efeito da sonotrombólise nos índices de motilidade e perfusão miocárdicas em pacientes com IAM-CSST, utilizando a ecocardiografia com perfusão miocárdica em tempo real (EPMTR). MÉTODO: Uma centena de pacientes com IAM-CSST foram randomizados em dois grupos: Terapia (50 pacientes tratados com sonotrombólise e angioplastia coronária primária) e Controle (50 pacientes tratados com angioplastia coronária primária). Os pacientes realizaram EPMTR para analisar a fração de ejeção do ventrículo esquerdo (FEVE), o índice de escore de motilidade segmentar (IEMS) e o número de segmentos com defeito de perfusão miocárdica, 72 horas após o IAM-CSST e com 6 meses de acompanhamento. Foi considerado significativo p < 0,05. RESULTADOS: Pacientes tratados com sonotrombólise apresentaram FEVE mais alta que o grupo Controle em 72 horas (50 ± 10% vs. 44 ± 10%; p = 0,006), e essa melhora foi mantida em seis meses (53 ± 10% vs. 48 ± 12%; p = 0,008). O IEMS foi similar nos grupos Terapia e Controle em 72 horas (1,62 ± 0,39 vs. 1,75 ± 0,40; p = 0,09), mas tornou-se menor no grupo Terapia em 6 meses (1,46 ± 0,36 vs. 1,64 ± 0,44; p = 0,02). O número de segmentos com defeito de perfusão não foi diferente entre os grupos em 72 horas (5,92 ± 3,47 vs. 6,94 ± 3,39; p = 0,15), mas ficou menor no grupo Terapia em 6 meses (4,64 ± 3,31 vs. 6,57 ± 4,29; p = 0,01). CONCLUSÃO: A sonotrombólise em pacientes com IAM-CSST resulta na melhora dos índices de motilidade e perfusão ventricular ao longo do tempo.


Asunto(s)
Infarto del Miocardio , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/terapia , Perfusión , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/terapia , Volumen Sistólico , Función Ventricular Izquierda
18.
J Refract Surg ; 38(5): 318-325, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35536713

RESUMEN

PURPOSE: To determine the effectiveness of parameters and indices based on biomechanical measures at discriminating fellow eyes with topographically and tomographically normal corneas in patients with keratoconus from normal control corneas. METHODS: The study included 47 keratoconus suspect eyes, defined as the topographically and tomographically normal fellow eyes of patients with frank keratoconus in the other eye. Eyes were imaged using the Pentacam HR and Corvis ST (both Oculus Optikgeräte GmbH). Fellow eyes were then categorized as topographically/tomographically normal fellow eyes (TNF) and topographically/tomographically borderline fellow eyes (TBF). The ability of each of the Corvis Biomechanical Index (CBI), Tomographic and Biomechanical Index (TBI), stiffness parameter at applanation 1 (SP-A1), and stress-strain index (SSI) at discriminating between normal controls and keratoconus suspects was assessed. RESULTS: The TBI had the best discriminative ability with the greatest area under the receiver operating characteristic (AUROC) curve value of 0.946 for normal controls versus TBF eyes, and 0.824 for normal controls versus TNF eyes. Compared to the TBI AUROC curves, SP-A1 and CBI had AUROC curve values of 0.833 (P = .09) and 0.822 (P = .01) for normal controls versus TBF eyes, respectively, and AUROC curve values of 0.822 (P = .96) and 0.550 (P = .0002) for normal controls versus TNF eyes, respectively. The TBI had the best positive predictive value for TNF and TBF eyes, followed by CBI and SP-A1. CONCLUSIONS: The TBI and the purely biomechanical parameter SP-A1 were of moderate utility in distinguishing between normal and keratoconus suspect eyes. In the absence of topographic/tomographic evidence of keratectasia, an independently abnormal biomechanical parameter may suggest an increased risk of ectasia. [J Refract Surg. 2022;38(5):318-325.].


Asunto(s)
Queratocono , Fenómenos Biomecánicos , Córnea/diagnóstico por imagen , Paquimetría Corneal/métodos , Topografía de la Córnea/métodos , Elasticidad , Humanos , Queratocono/diagnóstico , Curva ROC , Estudios Retrospectivos
19.
Front Bioeng Biotechnol ; 10: 834270, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35433653

RESUMEN

Purpose: The objective of this study is to evaluate the in vivo corneal biomechanical response to three laser refractive surgeries. Methods: Two hundred and twenty-seven patients who submitted to transepithelial photorefractive keratectomy (tPRK), femtosecond laser-assisted in-situ keratomileusis (FS-LASIK), or small-incision lenticule extraction (SMILE) were included in this study. All cases were examined with the Corvis ST preoperatively (up to 3 months) and postoperatively at 1, 3, and 6 months, and the differences in the main device parameters were assessed. The three groups were matched in age, gender ratio, corneal thickness, refractive error corrections, optical zone diameter, and intraocular pressure. They were also matched in the preoperative biomechanical metrics provided by the Corvis ST including stiffness parameter at first applanation (SP-A1), integrated inverse radius (IIR), deformation amplitude (DA), and deformation amplitude 2 mm away from apex and the apical deformation (DARatio2mm). Results: The results demonstrated a significant decrease post-operation in SP-A1 and significant increases in IIR, DA, and DARatio2mm (p < 0.05), all of which indicated reductions in overall corneal stiffness. Inter-procedure comparisons provided evidence that the smallest overall stiffness reduction was in the tPRK group, followed by the SMILE, and then the FS-LASIK group (p < 0.05). These results remained valid after correction for the change in CCT between pre and 6 months post-operation and for the percentage tissue altered. In all three surgery groups, higher degrees of refractive correction resulted in larger overall stiffness losses based on most of the biomechanical metrics. Conclusion: The corneal biomechanical response to the three surgery procedures varied significantly. With similar corneal thickness loss, the reductions in overall corneal stiffness were the highest in FS-LASIK and the lowest in tPRK.

20.
Curr Eye Res ; 47(7): 982-986, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35385372

RESUMEN

PURPOSE: To assess the biomechanical deterioration arising from keratoconus progression in-vivo. METHODS: The preoperative examinations of 32 progressive KC cases that were submitted to corneal cross-linking were evaluated. The examinations included the corneal tomography using the Pentacam HR and biomechanical parameters assessed by the Corvis ST (Oculus, Wetzlar, Germany). The results were recorded at two time points, the latter of which was at the last visit before the CXL procedure. Keratoconus progression was characterised by a significant change in the ABCD system. RESULTS: At the last follow-up visit (41.4 ± 40.9 months) all morphological parameters of the ABCD grading system showed significant deterioration (p < 0.001). The comparative analyses revealed a significant reduction in corneal stiffness expressed by a significant reduction in the stress-strain index (SSI: -0.10 ± 0.06, p < 0.001), the Stiffness parameter A1 (SP-A1: -6.1 ± 12.0 mmHg/mm, p = 0.011), by a significant increase in the integrated Inverse Radius (IIR: 0.95 ± 1.04 mm-1, p < 0.001) and in the deflection amplitude (DA) ratio (0.23 ± 0.58, p = 0.034). A barely significant increase in the DA also pointed towards corneal stiffness reduction. (0.04 ± 0.13 mm, p = 0.056). The SSI and the IIR were the indices with the smallest overlaps between the two examinations. CONCLUSIONS: It has been demonstrated in-vivo that corneal biomechanical deterioration occurs with keratoconus progression. The larger changes observed in the SSI and the IIR when compared to the remaining biomechanical parameters suggests that these parameters could be suitable to assess the corneal stiffness reduction in keratoconus natural progression.


Asunto(s)
Queratocono , Fenómenos Biomecánicos , Córnea/cirugía , Topografía de la Córnea/métodos , Elasticidad , Humanos , Queratocono/diagnóstico , Tomografía
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