Background: Most Leber hereditary optic neuropathy (LHON) cases are bilateral and sequential; however, there are rare unilateral examples, or those in which the delay of onset of vision loss between one and the other eye is longer. In the case of presumed childhood amblyopia in one eye, vision loss in the good eye may be the only symptom of bilateral disease, which was unnoticed in the previously amblyopic eye, or a preexisting episode of LHON in the “amblyopic” eye. The clinical decision in such cases may be difficult and suggestive of other forms of atypical optic neuropathy until confirmed by genetic testing. Case series: We present three genetically confirmed (MT-ND1:m.3700G>A, MT-ND6:m14484 T>C, and MT-ND4:m.11778G>A) patients with subacute vision loss in the previously good eye, with the other eye believed to be amblyopic from childhood and their features different from what would be expected in true amblyopia. In all, electrophysiology testing showed a bilaterally reduced amplitude of PERG with low VEP P100 wave amplitudes and prolonged peak time in both eyes, also unusual for amblyopia. During follow-up, the pallor of the optic discs progressed in all eyes. Significant thinning of the peripapillary retinal nerve fiber layer (pRNFL; retinal nerve fiber layer around the optic disc) and ganglion cell complex (GCC) in the macular region was present. All three patients had a peculiar history. The first patient was treated for presumed hyperopic amblyopia that did not improve since childhood, experienced visual loss in the good eye at the age of 17, and was negative for the three typical LHON mutations. Extended testing confirmed an atypical pathogenic variant MT-ND1:m.3700G>A in homoplasmy. The second patient with presumed strabismic amblyopia had an unusual presentation of vision loss only at the age of 61, and after the exclusion of other causes, a typical MT-ND4:m.11778G>A pathogenic variant was found in homoplasmy. The third case was peculiar as he had presumed strabismic amblyopia since childhood and had some degree of disc pallor in the amblyopic eye upon presenting with loss of vision in the good eye at the age of 21, and a typical pathogenic variant m14484 T>C, p.Met64Val was subsequently confirmed. However, one year after disease onset, he started to experience significant spontaneous functional improvement in the non-amblyopic up to 1.0 Snellen whilst improvement in the presumed amblyopic eye was modest, suggesting preexisting amblyopia. This interestingly extensive improvement was carefully followed by electrophysiology as well as visual acuity and fields. Conclusions: This report shows three different scenarios of presentation of LHON in patients with presumed uniocular amblyopia from childhood. In such cases, the diagnosis may be difficult, and detailed structural and functional evaluation of the optic nerve head is necessary to assess whether an earlier LHON episode was misdiagnosed as amblyopia or whether LHON presented bilaterally on both eyes whilst only being noticed in the previously good eye.

Background/Objectives: Clinical differentiation between Parkinson’s disease (PD) and atypical parkinsonism (AP) remains complex. Current diagnostic procedures helpful in their distinction lack specificity, making non-invasive tools like optical coherence tomography (OCT) crucial in evaluating possible retinal changes as potential biomarkers. Our study examined the thickness of the ganglion cell inner plexiform layer complex (GCIPL), peripapillary retinal nerve fiber layer (RNFL) and macular segments in individuals with PD, multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and healthy controls (HC). The objective of our study was to determine if OCT analyses can effectively discriminate PD patients from HC and whether retinal thickness can distinguish typical PD patients from those with AP. Methods: Research was an observational, cross-sectional study. Multiple retinal layers measured with OCT of PD and AP patients were compared with age- and sex-matched HC. An intergroup assessment was conducted. Results: Patients with PD and PSP exhibit a thinner GCIPL compared to HC, with no difference observed in the MSA group. GCIPL thickness between investigational groups does not differentiate between PD and AP. The RNFL and central macula thickness were statistically significantly reduced in all patient groups compared to HC. The RNFL was thinner in PSP compared to PD. Nearly all inner and outer macular segments were thinner in the investigational groups compared to HC. The preservation of outer nasal segments distinguished HC from both typical and AP. Patients with PSP and PD differed in the thickness of all macular segments, being thinner in PSP patients. Conclusions: Thickness of multiple retinal layers and macular regions might serve as a distinguishing feature between PD, AP and HC.

Reported tetracaine allergy, particularly in the absence of supporting medical documentation or a confirmed allergy diagnosis, represents a common challenge during the preoperative assessment of patients undergoing cataract surgery. In such cases, clinical decisions often rely primarily on patient history, which may be incomplete, inaccurate, or unreliable, resulting in considerable diagnostic uncertainty. A narrative review of the literature was conducted to examine the clinical relevance of reported tetracaine allergy in perioperative management of cataract surgery. Based on critical appraisal and synthesis of the available evidence, a phenotype-based framework comprising three clinical presentation phenotypes was developed, accompanied by a structured algorithm to support preoperative decision-making. The proposed framework classifies patients into three clinically relevant phenotypes: the irritative phenotype, the suspected hypersensitivity phenotype, and the clinical uncertainty phenotype. This classification provides a structured approach to interpreting reported tetracaine allergy and forms the basis of a practical algorithm for phenotype-guided preoperative management. The phenotype-based framework is intended to support, rather than replace, clinical judgment in the preoperative evaluation of patients with reported tetracaine allergy. By providing a structured approach to decision-making when diagnostic information is limited or uncertain, the framework may improve the consistency and transparency of perioperative management. Although conceptual, the proposed framework highlights the importance of obtaining reliable clinical information in patients reporting tetracaine allergy. Further methodological studies, including prospective validation, are required before the framework can be recommended for routine clinical practice.

Background: Penetrating keratoplasty (PK) is a technically demanding corneal transplant procedure frequently performed in elderly patients with substantial systemic comorbidities. In this population, an anesthetic strategy that ensures hemodynamic stability, cooperative sedation, adequate analgesia, and preserved spontaneous ventilation is highly desirable. Dexmedetomidine, a highly selective alpha2-adrenergic agonist, provides “cooperative” sedation with minimal risk of respiratory depression and additional sympatholytic benefits. Methods: This single-center retrospective observational case series included 50 consecutive patients (American Society of Anesthesiologists [ASA] II–III, age 50–90 years) undergoing PK under sub-Tenon block combined with continuous dexmedetomidine infusion. Dexmedetomidine was administered without a loading bolus at 0.7 mcg/kg/h for 10–15 min, then reduced to 0.5 mcg/kg/h, targeting a Ramsay Sedation Scale (RSS) score of 2–3. The sub-Tenon block was performed using a mixture of levobupivacaine 0.5% and lidocaine 2% (3–5 mL). Heart rate (HR), mean arterial pressure (MAP), oxygen saturation (SpO₂) and RSS were recorded in nine predefined perioperative phases. Data were analyzed descriptively. Results: The mean age was 72 ± 9 years; 52% of patients were ASA III. Hypertension was present in all patients; 30% had cardiovascular disease, 28% diabetes mellitus type II, and 30% chronic obstructive pulmonary disease. Progressive, controlled bradycardia was observed (mean HR decreased from 76 to 57 beats/min during graft transplantation), while MAP gradually decreased from hypertensive baseline values (150–160 mmHg) to an optimal intraoperative range of 115–130 mmHg, without episodes of clinically significant hypotension. SpO₂ remained stable at 98–99% throughout all phases, with no episodes of desaturation or need for airway intervention or supplemental oxygen. Target sedation (RSS 2–3) was achieved in all patients (median RSS 3), with preserved spontaneous breathing and cooperation. Sub-Tenon block-related bulging occurred in 6% of cases. No episodes of clinically significant bradycardia, malignant arrhythmia, respiratory compromise, or need to discontinue dexmedetomidine were recorded. No opioids or non-steroidal analgesics were required intraoperatively or in the early postoperative period. Conclusions: The combination of sub-Tenon block and continuous dexmedetomidine sedation without a loading bolus represents a hemodynamically stable and respiratory-safe anesthetic strategy for PK in elderly, high-risk patients. These preliminary, hypothesis-generating findings suggest that the protocol provides stable surgical conditions and a favorable safety profile, justifying future prospective randomized controlled trials to establish its comparative efficacy against general anesthesia or standard sedative regimens.

Leber hereditary optic neuropathy (LHON) is a mitochondrial neurodegenerative disease presented as a painless, acute, or subacute, usually sequential, loss of central visual acuity. The other eye is typically affected in a few weeks or months (on average in 6 to 8 weeks), while in about 25% of cases, the disease is simultaneously bilateral. Although individual unilateral cases have been reported, in 97% of cases, both eyes are affected within a year. Detailed genetic analysis is crucial in the process of diagnosing LHON. Between 75 - 90% of all the recorded LHON cases occur due to one of the three common mutations in mitochondrial DNA (mtDNA), located on nucleotides 11778, 14484, and 3460, although other, rare mutations with familial occurrence have been associated with LHON as well. More recently, the so-called autosomal recessive LHON has been described, which occurs due to a mutation in the DNAJC30 gene and presents with identical clinical features, but a better visual prognosis compared to mtLHON. This short review aims to present relevant information on the phenotype, genotype, and biochemical characteristics of LHON.