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1.
Graefes Arch Clin Exp Ophthalmol ; 262(4): 1337-1349, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37943332

ABSTRACT

Keratoconus is a blinding eye disease that affects activities of daily living; therefore, early diagnosis is crucial. Great efforts have been made toward an early diagnosis of keratoconus. Recent studies have shown that corneal biomechanics is associated with the occurrence and progression of keratoconus. Hence, detecting changes in corneal biomechanics may provide a novel strategy for early diagnosis. However, an early keratoconus diagnosis remains challenging due to the subtle and localized nature of its lesions. Artificial intelligence has been used to help address this problem. Herein, we reviewed the literature regarding three aspects of keratoconus (keratoconus, early keratoconus, and keratoconus grading) based on corneal biomechanical properties using artificial intelligence. Furthermore, we summarized the current research progress, limitations, and possible prospects.


Subject(s)
Keratoconus , Humans , Keratoconus/diagnosis , Artificial Intelligence , Corneal Topography , Biomechanical Phenomena , Activities of Daily Living , Cornea , Early Diagnosis
2.
Asia Pac J Ophthalmol (Phila) ; 12(6): 574-581, 2023.
Article in English | MEDLINE | ID: mdl-37973045

ABSTRACT

PURPOSE: This study aimed to develop a novel method to diagnose early keratoconus by detecting localized corneal biomechanical changes based on dynamic deformation videos using machine learning. DESIGN: Diagnostic research study. METHODS: We included 917 corneal videos from the Tianjin Eye Hospital (Tianjin, China) and Shanxi Eye Hospital (Xi'an, China) from February 6, 2015, to August 25, 2022. Scheimpflug technology was used to obtain dynamic deformation videos under forced puffs of air. Fourteen new pixel-level biomechanical parameters were calculated based on a spline curve equation fitting by 115,200-pixel points from the corneal contour extracted from videos to characterize localized biomechanics. An ensemble learning model was developed, external validation was performed, and the diagnostic performance was compared with that of existing clinical diagnostic indices. The performance of the developed machine learning model was evaluated using precision, recall, F1 score, and the area under the receiver operating characteristic curve. RESULTS: The ensemble learning model successfully diagnosed early keratoconus (area under the curve = 0.9997) with 95.73% precision, 95.61% recall, and 95.50% F1 score in the sample set (n=802). External validation on an independent dataset (n=115) achieved 91.38% precision, 92.11% recall, and 91.18% F1 score. Diagnostic accuracy was significantly better than that of existing clinical diagnostic indices (from 86.28% to 93.36%, all P <0.01). CONCLUSIONS: Localized corneal biomechanical changes detected using dynamic deformation videos combined with machine learning algorithms were useful for diagnosing early keratoconus. Focusing on localized biomechanical changes may guide ophthalmologists, aiding the timely diagnosis of early keratoconus and benefiting the patient's vision.


Subject(s)
Keratoconus , Humans , Keratoconus/diagnosis , Artificial Intelligence , Corneal Topography/methods , Cornea , ROC Curve , Biomechanical Phenomena , Retrospective Studies , Corneal Pachymetry
3.
Cureus ; 14(3): e22866, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35399479

ABSTRACT

Background The optimal treatment modality and choice of implant for unstable peritrochanteric fractures is debatable, with multiple options ranging from intramedullary to extramedullary implants. The purpose of this study was to evaluate the radiological and functional outcomes of 95° dynamic condylar screws in unstable intertrochanteric fractures. Patients and methods This is a retrospective review of patients with unstable peritrochanteric fractures (31-A2 and A3 for Association for Osteosynthesis/Association for the Study of Internal Fixation (AO/ASIF) classification) who underwent open reduction and internal fixation with 95° dynamic condylar screw at Recep Tayyip Erdogan Hospital between 2014 and 2018. All the patients had a minimum of one year of follow-up. Clinical outcomes were measured in terms of time to full weight bearing, Harris Hip Score, and time to radiographic union. Results This study comprised 84 patients (including 56 males and 28 females with a mean age of 57.2 ± 9.7 years). The average time to full weight bearing was 4.2 months (range: three to six months). The radiological union was seen at a mean of 5.8 months (range: 4-11 months). Functional outcome in terms of Harris Hip Score was graded as excellent, good, fair, and poor in 18, 45, 16, and five patients, respectively. Implant failure was observed in three patients. One patient sustained a peri-prosthetic fracture, which was treated with a longer plate. Conclusion Dynamic condylar screw proves to be a reliable implant when used in unstable peritrochanteric fractures and results in satisfactory functional and radiological outcomes.

4.
J Refract Surg ; 31(11): 752-8, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26544563

ABSTRACT

PURPOSE: To investigate the characteristics of forward light scatter changes after small incision lenticule extraction (SMILE) and to compare these changes with those after femtosecond laser-assisted LASIK (femto-LASIK) and epipolis LASIK (epi-LASIK). METHODS: A total of 303 eyes (SMILE group = 118 eyes, femto-LASIK group = 90 eyes, epi-LASIK group = 95) of 157 patients were included in this study. Forward straylight was measured preoperatively and 1 month, 6 months, and 1 year postoperatively using a C-Quant straylight meter (Oculus Optikgeräte, Wetzlar, Germany). RESULTS: A significant increase in straylight was found in the femto-LASIK group only at 1 month after the procedure (P = .002), whereas significant increases were found in the epi-LASIK group at 1 month, 6 months, and 1 year after the procedure (P < .001). There were no significant increases in the straylight values after SMILE (P = .310) compared with the preoperative values, although the straylight values were slightly increased at 1 month. Significant differences in the postoperative-preoperative straylight value (Δlog[s]) changes were found between the SMILE, femto-LASIK, and epi-LASIK groups over the follow-up period (P < .001 for all). The correlations between the ablation depth/central corneal thickness ratios and the straylight values were statistically significant in the femto-LASIK and epi-LASIK groups, whereas no significant correlation between the lenticule thickness/central corneal thickness ratios and the stray-light values was found in the SMILE group. CONCLUSIONS: Forward straylight was slightly increased in the early stage after the femto-LASIK procedure and was significantly increased throughout the follow-up period after epi-LASIK surgery. The SMILE procedure appeared to have a smaller effect on forward light scatter within the 1-year follow-up period.


Subject(s)
Astigmatism/surgery , Corneal Stroma/surgery , Keratomileusis, Laser In Situ/methods , Lasers, Excimer/therapeutic use , Myopia/surgery , Scattering, Radiation , Vision Disorders/diagnosis , Adult , Corneal Surgery, Laser/methods , Female , Glare , Humans , Light , Male , Photometry , Prospective Studies , Young Adult
5.
J Coll Physicians Surg Pak ; 25(8): 621-2, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26305314

ABSTRACT

Ichthyosisis an infrequent clinical entity worldwide with an incidence of 1:600,000 births. It can be one of the two types: collodion baby and Harlequin fetus or malignant keratoma (most severe form). The clinical manifestations in either form are thick and hard skin with deep splits. Affected babies are born in a collodion membrane, a shiny waxy outer layer to the skin that is shed 10 - 14 days after birth, revealing the main symptom of the disease. The reported case is of a neonate, born to primigravida mother at seven and a half month's gestation with a birth weight of 2160 grams and Apgar score of 6/10 and 8/10 at 1 and 5 minutes respectively. Conclusively, early diagnosis of this condition can help cope and prevent serious morbidity or even mortality at time. These newborns should be monitored carefully in intensive care units by a multi-disciplinary team.


Subject(s)
Abnormalities, Multiple/pathology , Ichthyosis, Lamellar/diagnosis , Skin/pathology , Humans , Ichthyosis, Lamellar/genetics , Infant, Newborn , Male , Skin Abnormalities/pathology
6.
J Coll Physicians Surg Pak ; 23(3): 203-7, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23458044

ABSTRACT

OBJECTIVE: To determine the outcome of intramedullary interlocking surgical implant generation network (SIGN) nail in diaphyseal tibial fractures in terms of union and failure of implant (breakage of nail or interlocking screws). STUDY DESIGN: Case series. PLACE AND DURATION OF STUDY: Orthopaedics and Spinal Surgery, Ghurki Trust Teaching Hospital, Lahore Medical and Dental College, Lahore, from September 2008 to August 2009. METHODOLOGY: Fifty patients aged 14 - 60 years, of either gender were included, who had closed and Gustilo type I and II open fractures reported in 2 weeks, whose closed reduction was not possible or was unsatisfactory and fracture was located 7 cm below knee joint to 7 cm above ankle joint. Fractures previously treated with external fixator, infected fractures and unfit patients were excluded. All fractures were fixed with intramedullary interlocking SIGN nail and were followed clinically and radiographically for union and for any implant failure. RESULTS: Forty one (88%) patients had united fracture within 6 months, 5 (10%) patients had delayed union while 4 (8%) patients had non-union. Mean duration for achieving union was 163 + 30.6 days. Interlocking screws were broken in 2 patients while no nail was broken in any patient. CONCLUSION: Intramedullary interlocking nailing is an effective measure in treating closed and grade I and II open tibial fractures. It provides a high rate of union less complications and early return to function.


Subject(s)
Bone Nails , Fracture Fixation, Intramedullary/instrumentation , Fracture Fixation, Intramedullary/methods , Fractures, Open/surgery , Tibial Fractures/surgery , Adolescent , Adult , Age Distribution , Diaphyses , Female , Fracture Healing , Fractures, Closed/surgery , Fractures, Comminuted/surgery , Humans , Male , Middle Aged , Pain, Postoperative/etiology , Recovery of Function , Sex Distribution , Tibial Fractures/diagnostic imaging , Tomography, X-Ray Computed , Treatment Outcome , Young Adult
7.
Cardiovasc Res ; 53(4): 984-92, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11922908

ABSTRACT

OBJECTIVE: Thrombin activates platelets and contributes to the occlusion of arteries following thrombolytic therapy or angioplasty. Thrombostatin (RPPGF), the angiotensin converting enzyme degradation product of bradykinin, inhibits alpha-thrombin induced platelet activation. We hypothesized that thrombostatin prevents platelet aggregation and adhesion after balloon angioplasty (BA). METHODS: Platelet-rich plasma (PRP) was obtained from 22 Beagle dogs before sacrifice and 10% of the PRP was labeled with 111In. Carotid arteries were then removed from each dog and mounted in a dual perfusion chamber and intimal injury was performed with BA. 111In-PRP with or without thrombostatin or aspirin alone was perfused through the arteries for 60 min. During perfusion, platelet volume was measured using a Coulter counter and a laser-light scattering technique. Platelet adhesion to arteries was measured by radioactivity count. RESULTS: Arterial injury alone compared to non-injury increased platelet volume in the circuit by 1.4 times (x) (P<0.05) using a Coulter counter or 1.8x (P<0.05) using laser-light scattering and increased platelet adhesion by 2.3x (P<0.01). When compared to BA injury alone, the addition of thrombostatin reduced platelet volume by 1.8x (P<0.03) as measured by Coulter counter or 1.9x (P<0.01) by laser-light scattering and platelet adhesion by 4.2x (P<0.05). Compared to BA injury alone, aspirin reduced platelet volume by 1.2x (P<0.01) as assessed by Coulter counter or 1.5x (P<0.03) using laser-light scattering and platelet adhesion by 1.8x (P<0.02). CONCLUSION: Thrombostatin or aspirin independently decreases evidence of platelet activation in the canine carotid artery model of BA injury.


Subject(s)
Bradykinin/metabolism , Bradykinin/pharmacology , Carotid Artery Injuries/pathology , Catheterization/adverse effects , Peptide Fragments/pharmacology , Platelet Activation/drug effects , Animals , Aspirin/pharmacology , Blood Platelets/drug effects , Blood Platelets/pathology , Carotid Arteries/ultrastructure , Carotid Artery Injuries/etiology , Carotid Stenosis/therapy , Cell Size/drug effects , Disease Models, Animal , Dogs , Lasers , Microscopy, Electron, Scanning , P-Selectin/metabolism , Platelet Aggregation , Platelet Aggregation Inhibitors/pharmacology , Scattering, Radiation
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