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Journal Francais D'ophtalmologie Nov 2023
Topics: Humans; Horner Syndrome; Thyroid Neoplasms; Female; Middle Aged
PubMed: 37495475
DOI: 10.1016/j.jfo.2023.02.016 -
Radiographics : a Review Publication of... Feb 2024Patients presenting with visual disturbances often require a neuroimaging approach. The spectrum of visual disturbances includes three main categories: vision...
Patients presenting with visual disturbances often require a neuroimaging approach. The spectrum of visual disturbances includes three main categories: vision impairment, ocular motility dysfunction, and abnormal pupillary response. Decreased vision is usually due to an eye abnormality. However, it can also be related to other disorders affecting the visual pathway, from the retina to the occipital lobe. Ocular motility dysfunction may follow disorders of the cranial nerves responsible for eye movements (ie, oculomotor, trochlear, and abducens nerves); may be due to any abnormality that directly affects the extraocular muscles, such as tumor or inflammation; or may result from any orbital disease that can alter the anatomy or function of these muscles, leading to diplopia and strabismus. Given that pupillary response depends on the normal function of the sympathetic and parasympathetic pathways, an abnormality affecting these neuronal systems manifests, respectively, as pupillary miosis or mydriasis, with other related symptoms. In some cases, neuroimaging studies must complement the clinical ophthalmologic examination to better assess the anatomic and pathologic conditions that could explain the symptoms. US has a major role in the assessment of diseases of the eye and anterior orbit. CT is usually the first-line imaging modality because of its attainability, especially in trauma settings. MRI offers further information for inflammatory and tumoral cases. RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.
Topics: Humans; Vision Disorders; Oculomotor Muscles; Orbit; Magnetic Resonance Imaging
PubMed: 38271255
DOI: 10.1148/rg.230081 -
Acta Pharmacologica Sinica Apr 2024Morphine and morphine-6-glucuronide (M6G) produce central nervous system (CNS) effects by activating mu-opioid receptors, while naloxone is used mainly for the reversal...
Morphine and morphine-6-glucuronide (M6G) produce central nervous system (CNS) effects by activating mu-opioid receptors, while naloxone is used mainly for the reversal of opioid overdose, specifically for the fatal complication of respiratory depression, but also for alleviating opioid-induced side effects. In this study we developed a physiologically-based pharmacokinetic-pharmacodynamic (PBPK-PD) model to simultaneously predict pharmacokinetics and CNS effects (miosis, respiratory depression and analgesia) of morphine as well as antagonistic effects of naloxone against morphine. The pharmacokinetic and pharmacodynamic parameters were obtained from in vitro data, in silico, or animals. Pharmacokinetic and pharmacodynamic simulations were conducted using 39 and 36 clinical reports, respectively. The pharmacokinetics of morphine and M6G following oral or intravenous administration were simulated, and the PBPK-PD model was validated using clinical observations. The E model correlated CNS effects with free concentrations of morphine and M6G in brain parenchyma. The predicted CNS effects were compared with observations. Most clinical observations fell within the 5th-95th percentiles of simulations based on 1000 virtual individuals. Most of the simulated area under the concentration-time curve or peak concentrations also fell within 0.5-2-fold of observations. The contribution of morphine to CNS effects following intravenous or oral administration was larger than that of M6G. Pharmacokinetics and antagonistic effects of naloxone on CNS effects were also successfully predicted using the developed PBPK-PD model. In conclusion, the pharmacokinetics and pharmacodynamics of morphine and M6G, antagonistic effects of naloxone against morphine-induced CNS effects may be successfully predicted using the developed PBPK-PD model based on the parameters derived from in vitro, in silico, or animal studies.
PubMed: 38570601
DOI: 10.1038/s41401-024-01255-2 -
Open Veterinary Journal Oct 2023Intra-lenticular foreign bodies are rare in veterinary medicine and uncommon in human medicine. Approximately 50% of perforating ocular injuries in canines have...
BACKGROUND
Intra-lenticular foreign bodies are rare in veterinary medicine and uncommon in human medicine. Approximately 50% of perforating ocular injuries in canines have lenticular involvement. Treatment choices include conservative management and surgical options. Retained intra-lenticular foreign body with delayed removal has not been reported in animals.
CASE DESCRIPTION
A 3-year-old male neutered Lurcher presented with right-sided ocular discomfort and a sealed full-thickness corneal perforation. The full ophthalmic examination could not be performed at the initial presentation due to miosis. Recrudescence of anterior uveitis was seen post-drug cessation. Re-evaluation of the eye with a mydriatic pupil revealed an intra-lenticular foreign body. Surgical removal via phacoemulsification was performed 8 weeks after the initial perforating injury. The eye remains visual, comfortable, and normotensive 50 months post-operatively.
CONCLUSION
This is the first report of an encapsulated, retained intra-lenticular foreign body with delayed removal in a dog. Mydriasis and repeat examinations are of crucial importance when evaluating eyes post-perforation.
Topics: Humans; Male; Dogs; Animals; Lens, Crystalline; Eye Foreign Bodies; Phacoemulsification; Dog Diseases
PubMed: 38027412
DOI: 10.5455/OVJ.2023.v13.i10.18 -
Neurology India 2023
Review
Topics: Humans; Carotid Artery, Internal; Carotid Artery, Internal, Dissection; Horner Syndrome; Magnetic Resonance Angiography
PubMed: 37929475
DOI: 10.4103/0028-3886.388041 -
Investigative Ophthalmology & Visual... Nov 2023A previous study demonstrated upper eyelid retraction synchronized with pupil dilation following a transition from photopic to scotopic conditions. The current study...
PURPOSE
A previous study demonstrated upper eyelid retraction synchronized with pupil dilation following a transition from photopic to scotopic conditions. The current study aimed to evaluate the role of Müller's muscle as the efferent arm of this suggested reflex arc.
METHODS
A video scan of both eyes of patients with unilateral Horner syndrome was performed using optical coherence tomography infra-red mode to document the transition between photopic and scotopic conditions. The affected side with sympathetic denervation was the study group, whereas the contralateral unaffected side of the same patients served as the control group. The pupil diameter, upper eyelid margin-to-reflex distance 1, lower eyelid margin-to-reflex distance 2, and vertical palpebral fissure height were measured. The control group was compared to the healthy subjects of a previous study to verify any compensatory changes to the side contralateral to denervation.
RESULTS
Ten patients with unilateral Horner Syndrome were included in the study. Transitioning from photopic to scotopic conditions, the mean change in margin-to-reflex distance 1 in the study and control groups was 315 ± 276 µm (P < 0.05) and 723 ± 432 µm (P = 0.005), respectively. Margin-to-reflex distance 1 and palpebral fissure height were significantly higher in the control group both in photopic (P = 0.005 and P = 0.017, respectively) and scotopic conditions (P = 0.005 and P = 0.007, respectively). The change in margin-to-reflex distance 1 and palpebral fissure height following the transition from light to dark was significantly greater in the control group (P = 0.022).
CONCLUSIONS
Reflexive eyelid retraction following a transition from photopic to scotopic conditions was significantly diminished in eyelids with sympathetic denervation compared with the unaffected contralateral side of the same patients. This study provides further evidence that the sympathetically innervated Müller's muscle serves as the efferent arm of this reflex.
Topics: Humans; Horner Syndrome; Eyelids; Eyelid Diseases; Oculomotor Muscles; Reflex; Blepharoptosis
PubMed: 38010698
DOI: 10.1167/iovs.64.14.35 -
Medical Journal, Armed Forces India Dec 2023A 30-year-old male patient presented to the eye department with complaints of blurring of vision of right eye at distance and near for a duration of 1.5 months. Ocular...
A 30-year-old male patient presented to the eye department with complaints of blurring of vision of right eye at distance and near for a duration of 1.5 months. Ocular examination revealed Anisocoria with enlarged pupil in the right eye. On instillation of 0.1% pilocarpine, there was a pronounced miosis in the dilated pupil seen at 30 min associated with an improvement in distance and near vision. On slit lamp examination, vermiform movements were seen in the affected pupil on shining the slit from temporal aspect. Fundus examination was within normal limits. Systemic examination revealed absent deep tendon reflexes. Based on the clinical features, a diagnosis of Holmes-Adie syndrome was reached and the patient was started on 0.1% pilocarpine eye drops. This case highlights the importance of thorough systemic examination and investigations in all cases of anisocoria.
PubMed: 38144644
DOI: 10.1016/j.mjafi.2022.01.008 -
Journal of AAPOS : the Official... Jun 2024Aberrant regeneration occurs in forms of oculomotor motor nerve palsy and frequently involves the pupil, but the incidence and functional impact of ciliary muscle...
Aberrant regeneration occurs in forms of oculomotor motor nerve palsy and frequently involves the pupil, but the incidence and functional impact of ciliary muscle involvement in pediatric patients is sparsely reported in the literature. A 4-year-old girl presented with inflammatory oculomotor motor nerve paresis affecting the inferior division. Initial treatment focused on her inability to accommodate through her physiologic +2.5 D hyperopia and the prevention and treatment of amblyopia. She subsequently developed aberrant regeneration of the pupil, with miosis on adduction. Following eye muscle surgery for residual exotropia and hypertropia, her dry refraction was noted to be more myopic in the affected eye on adduction, mirroring aberrant pupillary constriction. Recognition of pediatric aberrant regeneration of accommodation may influence surgical planning for oculomotor nerve palsy and/or management of amblyopia.
Topics: Humans; Female; Child, Preschool; Accommodation, Ocular; Oculomotor Nerve Diseases; Oculomotor Muscles; Ophthalmologic Surgical Procedures; Miosis; Exotropia
PubMed: 38588860
DOI: 10.1016/j.jaapos.2024.103917 -
Clinical Physiology and Functional... Apr 2024It is controversial whether people with vasovagal syncope (VVS) have abnormal autonomic responses at baseline and whether specific diagnostic manoeuvres have a...
It is controversial whether people with vasovagal syncope (VVS) have abnormal autonomic responses at baseline and whether specific diagnostic manoeuvres have a diagnostic value. We investigated whether the pupillary light reflex and cardiac autonomic tests can be used to identify autonomic dysfunction in volunteers with a medical history of VVS. The study groups included 128 healthy volunteers, of whom 31 reported a history of typical VVS. The right pupil was evaluated using an automated, commercial infra-red pupillometer under strict conditions. In addition to miosis and mydriasis kinetics, pupil diameters were measured. Heart rate variability at rest and heart rate changes to standing were quantified with high-resolution electrocardiography and designated software. The demographic and clinical characteristics of both groups were statistically similar. Average constriction velocity (ACV) was significantly higher in VVS patients following a univariate analysis (3.83 ± 0.59 vs. 3.56 ± 0.73 mm/s, p = 0.042) and after correcting for potential confounders (p = 0.049). All other pupillometric and heart rate indices were comparable between groups. Patients with a history of VVS depict pupillary parasympathetic overactivity in response to light stimuli, manifested as increased ACV. The prognostic implications of this finding and the significance of using this simple clinical tool to identify patients who are at risk for developing frequent episodes of VVS or physical injuries following a syncope merits further study.
PubMed: 38678442
DOI: 10.1111/cpf.12884 -
Biological & Pharmaceutical Bulletin Jan 2024Diclofenac instillation is useful in preventing intraoperative miosis and macular edema caused by postoperative inflammation in cataract surgery; however, optimum...
Diclofenac instillation is useful in preventing intraoperative miosis and macular edema caused by postoperative inflammation in cataract surgery; however, optimum efficacy is not attained when the instilled diclofenac strongly binds to albumin in patients' aqueous humor. Therefore, a method that inhibits diclofenac binding and increases the concentration of its free fraction is needed. We conducted a basic study regarding the effects of inhibitors on the binding of instilled diclofenac to albumin and endogenous substances in aqueous humor. Aqueous humor samples from 16 patients were pooled together for analysis. The free fraction of diclofenac was measured using ultrafiltration methods in various experiments with pooled and mimic aqueous humor. Free fraction of diclofenac, a site II drug, in pooled aqueous humor was 0.363 ± 0.013. The binding of diclofenac in the presence of phenylbutazone (PB), a site I inhibitor, was significantly inhibited (free fraction = 0.496 ± 0.013); however, no significant inhibition by ibuprofen, a site II inhibitor, (free fraction = 0.379 ± 0.004), was observed. The unexpected result was due to free fatty acids (FFAs; palmitic acid (PA)) and L-tryptophan (Trp). The inhibition of diclofenac binding by PB in the mimic aqueous humor containing these endogenous substances revealed significant binding inhibition in the presence of PA and Trp. Diclofenac is strongly rebound from site II to site I in the presence of FFAs and Trp in the aqueous humor because FFAs and Trp induce a conformational change in albumin. Therefore, PB significantly inhibits the binding of diclofenac to albumin.
Topics: Humans; Diclofenac; Anti-Inflammatory Agents, Non-Steroidal; Aqueous Humor; Cataract; Albumins
PubMed: 38057117
DOI: 10.1248/bpb.b23-00301