Disminución de la agudeza visual tras un procedimiento odontológico: A propósito de un caso / Unilateral visual impairment after a dental procedure: Case report

El uso de anestésicos locales para la realización de procedimientos odontológicos es una práctica ampliamente extendida que puede causar efectos adversos. Sin embargo, muy infrecuentemente puede causar complicaciones oculares como diplopía, ptosis, visión borrosa, miosis, disminución de la agudeza visual o amaurosis. Presentamos un caso de un paciente varón de 26 años que se presentó a la consulta por una disminución de la agudeza visual en su ojo derecho 48h después de una intervención odontológica del lado ipsilateral, logrando una recuperación de la misma en los 6 meses posteriores, sin tratamiento alguno. Diferentes teorías que justifiquen la aparición de complicaciones oculares como consecuencia de esta clase de procedimientos han sido propuestas en la literatura. En nuestro caso, una inyección intravenosa inadvertida habría sido la causa posible del hecho (AU)

The use of intra-oral local anaesthetics for dental procedures is a widely extended practice that may cause side effects. As such, in rare cases it may cause ocular complications such as diplopia, ptosis, blurry vision, miosis, vision loss, or amaurosis. (Most of them are transient, recovering after several hours or days). A case is presented of a 26 year-old male patient who had visual impairment in the right eye 2 days after a dental procedure was performed. Six months later he had a complete restoration of the previous visual acuity, despite the fact that he had not received any treatment. Several ways have been proposed in the literature that may explain the appearance of ocular complications following these kinds of procedures. In this case, inadvertent intravenous injection is believed to have been the cause (AU)

Unilateral visual impairment after a dental procedure: Case report.

The use of intra-oral local anaesthetics for dental procedures is a widely extended practice that may cause side effects. As such, in rare cases it may cause ocular complications such as diplopia, ptosis, blurry vision, miosis, vision loss, or amaurosis. (Most of them are transient, recovering after several hours or days). A case is presented of a 26 year-old male patient who had visual impairment in the right eye 2 days after a dental procedure was performed. Six months later he had a complete restoration of the previous visual acuity, despite the fact that he had not received any treatment. Several ways have been proposed in the literature that may explain the appearance of ocular complications following these kinds of procedures. In this case, inadvertent intravenous injection is believed to have been the cause.

Unilateral visual impairment after a dental procedure: Case report. / Disminución de la agudeza visual tras un procedimiento odontológico: A propósito de un caso.

The use of intra-oral local anaesthetics for dental procedures is a widely extended practice that may cause side effects. As such, in rare cases it may cause ocular complications such as diplopia, ptosis, blurry vision, miosis, vision loss, or amaurosis. (Most of them are transient, recovering after several hours or days). A case is presented of a 26 year-old male patient who had visual impairment in the right eye 2 days after a dental procedure was performed. Six months later he had a complete restoration of the previous visual acuity, despite the fact that he had not received any treatment. Several ways have been proposed in the literature that may explain the appearance of ocular complications following these kinds of procedures. In this case, inadvertent intravenous injection is believed to have been the cause.

[Patellofemoral arthroplasty]. / Der femoropatellare Teilersatz.

OBJECTIVE: Isolated resurfacing of the trochlea using an inlay prosthesis without changing the complex kinematics of the patellofemoral joint. INDICATIONS: Symptomatic, isolated patellofemoral osteoarthritis or isolated osteochondral lesions, failed conservative and cartilage regeneration procedures. No or concurrently corrected ligament instability, tibiofemoral and patellofemoral malalignment. CONTRAINDICATIONS: Symptomatic patellofemoral osteoarthritis, inflammatory joint disease, chondrocalcinosis, chronic pain syndromes, active infections or knee ankylosis. SURGICAL TECHNIQUE: Following a medial arthrotomy, coronal and sagittal curvatures of the trochlea are measured. Based on these measurements, corresponding surface reamers create an implant bed by removing damaged cartilage of the trochlea. A central fixation screw is placed to the desired depth and the inlay prosthesis is tapped carefully onto it. Final placement of the prosthesis is targeted slightly recessed to the surrounding joint surface. POSTOPERATIVE MANAGEMENT: Free passive range of motion exercises of the knee joint are recommended starting on postoperative day 1. Depending on symptoms (e.g., pain and joint effusion), partial weight-bearing of 20 kg is allowed during postoperative weeks 1 and 2, which is increased by 20 kg/week thereafter. RESULTS: In a prospective study of 29 patients (mean age: 42 years) treated with inlay arthroplasty, 2­year follow-up results showed significant improvements (p < 0.05) in WOMAC, IKDC and VAS (pain) scores when compared to baseline. Compared to onlay PF arthroplasty modern inlay prosthetic placement showed a better preservation of the tibiofemoral joint without progression of tibiofemoral degeneration. This may be due to possible avoidance of patellofemoral overstuffing using a more physiological placement of the inlay prosthesis.

[Patellofemoral arthroplasty: indication, technique and results]. / Patellotrochlearer Ersatz: Indikation, Technik und Ergebnisse.

BACKGROUND: Although patellofemoral arthroplasty has been used for more than 30 years, it is still a challenging subject in orthopedics. The reason for this are the complex kinematics of the patellofemoral joint which are influenced by dynamic and static factors. New implant concepts that incorporate multiple coronal and sagittal curvatures and surface controlled inlay implantation show a positive direction in modern patellofemoral arthroplasty. OBJECTIVES: The purpose of this work is the review of the literature on patellofemoral arthroplasty and the presentation of our own experience. METHODS: We present indications and surgical techniques of patellofemoral arthroplasty as well as the most important aspects of preoperative evaluation. The patellofemoral joint can be reconstructed using either an inlay or an onlay prosthesis. Both arthroplasty concepts are discussed. Additional pathologies like chronic patellofemoral instabilities due to dysplasia, valgus/varus or rotational malalignment, and soft-tissue alterations are addressed with concomitant procedures. RESULTS: Both inlay and onlay arthroplasty have demonstrated good functional outcome scores in patients with patellofemoral osteoarthritis. Patients with patellofemoral instability and/or trochlear dysplasia may benefit more from patellofemoral arthroplasty than patients with primary osteoarthritis because not only pain but also secondary pathologies are addressed. CONCLUSION: Patellofemoral arthroplasty is an effective and safe procedure if the indication criteria are respected and the specific surgical technique is used. However, comparative results on current inlay and onlay prostheses have not been published in the literature to date.

Common time-frequency analysis of local field potential and pyramidal cell activity in seizure-like events of the rat hippocampus.

To study cell-field dynamics, physiologists simultaneously record local field potentials and the activity of individual cells from animals performing cognitive tasks, during various brain states or under pathological conditions. However, apart from spike shape and spike timing analyses, few studies have focused on elucidating the common time-frequency structure of local field activity relative to surrounding cells across different periods of phenomena. We have used two algorithms, multi-window time frequency analysis and wavelet phase coherence (WPC), to study common intracellular-extracellular (I-E) spectral features in spontaneous seizure-like events (SLEs) from rat hippocampal slices in a low magnesium epilepsy model. Both algorithms were applied to 'pairs' of simultaneously observed I-E signals from slices in the CA1 hippocampal region. Analyses were performed over a frequency range of 1-100 Hz. I-E spectral commonality varied in frequency and time. Higher commonality was observed from 1 to 15 Hz, and lower commonality was observed in the 15-100 Hz frequency range. WPC was lower in the non-SLE region compared to SLE activity; however, there was no statistical difference in the 30-45 Hz band between SLE and non-SLE modes. This work provides evidence of strong commonality in various frequency bands of I-E SLEs in the rat hippocampus, not only during SLEs but also immediately before and after.

High frequency stimulation or elevated K+ depresses neuronal activity in the rat entopeduncular nucleus.

High frequency stimulation (HFS) is applied to many brain regions to treat a variety of neurological disorders/diseases, yet the mechanism(s) underlying its effects remains unclear. While some studies showed that HFS inhibits the stimulated nucleus, others report excitation. In this in vitro study, we stimulated the rat globus pallidus interna (entopeduncular nucleus, EP), a commonly stimulated area for Parkinson's disease, to investigate the effect of HFS-induced elevation of extracellular potassium (K(+)(e)) on rat EP neuronal activity. Whole-cell patch-clamp recordings and [K(+)](e) measurements were obtained in rat EP brain slices before, during and after HFS. After HFS (150 Hz, 10 s), [K(+)](e) increased from 2.5-9.6+/-1.4 mM, the resting membrane potential of EP neurons depolarized by 11.1+/-2.5 mV, spiking activity was significantly depressed, and input resistance decreased by 25+/-6%. The GABA(A) receptor blocker, gabazine, did not prevent these effects. The bath perfusion of 6 or 10 mM K(+), with or without synaptic blockers, mimicked the HFS-mediated effects: inhibition of spike activity, a 20+/-9% decrease in input resistance and a 17.4+/-3.0 mV depolarization. This depolarization exceeded predicted values of elevated [K(+)](e) on the resting membrane potential. A depolarization block did not fully account for the K(+)-induced inhibition of EP neuronal activity. Taken together, our results show that HFS-induced elevation of [K(+)](e) decreased EP neuronal activity by the activation of an ion conductance resulting in membrane depolarization, independent of synaptic involvement. These findings could explain the inhibitory effects of HFS on neurons of the stimulated nucleus.