Legg-Calve-Perthes' disease: an opportunity to prevent blindness?

Legg-Calve-Perthes' disease (LCP) is defined as avascular necrosis of the femoral head in a child and may present to a variety of disciplines from general practice to orthopaedics, paediatrics, rheumatology and more. The Stickler syndromes are a group of disorders of type II, IX and XI collagen associated with hip dysplasia, retinal detachment, deafness and cleft palate. The pathogenesis of LCP disease remains an enigma but there have been a small number of cases reporting variants in the gene encoding the α1 chain of type II collagen (COL2A1). Variants in COL2A1 are known to cause type 1 Stickler syndrome (MIM 108300, 609508), which is a connective tissue disorder with a very high risk of childhood blindness, and it is also associated with dysplastic development of the femoral head. It is unclear whether COL2A1 variants make a definitive contribution to both disorders, or whether the two are indistinguishable using current clinical diagnostic techniques. In this paper, we compare the two conditions and present a case series of 19 patients with genetically confirmed type 1 Stickler syndrome presenting with a historic diagnosis of LCP. In contrast to isolated LCP, children with type 1 Stickler syndrome have a very high risk of blindness from giant retinal tear detachment, but this is now largely preventable if a timely diagnosis is made. This paper highlights the potential for avoidable blindness in children presenting to clinicians with features suggestive of LCP disease but with underlying Stickler syndrome and proposes a simple scoring system to assist clinicians.

Surgical management of aphakia.

Despite the safety and efficacy of cataract surgery, intraoperative complications can hamper the ability to place an intraocular lens in the capsular bag. With vast numbers of cataract surgeries performed daily, complications occur often enough that every ophthalmologist should be equipped with techniques to manage aphakia. Medical management of aphakia used to be commonplace but these techniques have their disadvantages including thick bulky lenses, poor cosmesis, and aniseikonia. Surgical management of aphakia overcomes these disadvantages and offers patients the possibility of a spectacle and contact lens-free lifestyle. This article reviews the various options of surgical management of aphakia and their advantages and disadvantages. Comparison of outcomes between techniques and a protocol for deciding between techniques is presented.

Autosomal Recessive Stickler Syndrome.

Stickler syndrome (SS) is a genetic disorder with manifestations in the eye, ear, joints, face and palate. Usually inherited in a dominant fashion due to heterozygous pathogenic variants in the collagen genes COL2A1 and COL11A1, it can rarely be inherited in a recessive fashion from variants in COL9A1, COL9A2, and COL9A3, COL11A1, as well as the non-collagen genes LRP2, LOXL3 and GZF1. We review the published cases of recessive SS, which comprise 40 patients from 23 families. Both homozygous and compound heterozygous pathogenic variants are found. High myopia is near-universal, and sensorineural hearing loss is very common in patients with variants in genes for type IX or XI collagen, although hearing appears spared in the LRP2 and LOXL3 patients and is variable in GZF1. Cleft palate is associated with type XI collagen variants, as well as the non-collagen genes, but is so far unreported with type IX collagen variants. Retinal detachment has occurred in 18% of all cases, and joint pain in 15%. However, the mean age of this cohort is 11 years old, so the lifetime incidence of both problems may be underestimated. This paper reinforces the importance of screening for SS in congenital sensorineural hearing loss, particularly when associated with myopia, and the need to warn patients and parents of the warning signs of retinal detachment, with regular ophthalmic review.

Prevention of Blindness in Stickler Syndrome.

Stickler syndromes are inherited conditions caused by abnormalities of structural proteins in the eye, inner ear and cartilage. The risk of retinal detachment, particularly due to the development of giant retinal tears, is high. Stickler syndrome is the most common cause of childhood retinal detachment. Although retinal detachment surgery in the general population has a high success rate, outcomes from surgical repair in Stickler syndrome patients are notoriously poor, providing a strong argument for prophylactic intervention. Variable case selection, absence of molecular genetic sub-typing and inconsistent treatment strategies have all contributed to the historic uncertainty regarding the safety and efficacy of prophylactic treatment. This paper reviews the major published clinical studies that have evaluated different methods and strategies for prophylaxis. Based on the current body of literature, there is extremely strong evidence from cohort comparison studies demonstrating the efficacy and safety of prophylactic retinopexy to reduce, but not eliminate, the risk of retinal detachment in Stickler syndrome patients. It is vital that this body of evidence is provided to Stickler syndrome patients, to enable them to make their own fully informed choice about whether to receive prophylaxis for themselves and particularly on behalf of their affected children, to reduce the risk of retinal detachment.

Dominant Stickler Syndrome.

The Stickler syndromes are a group of genetic connective tissue disorders associated with an increased risk of rhegmatogenous retinal detachment, deafness, cleft palate, and premature arthritis. This review article focuses on the molecular genetics of the autosomal dominant forms of the disease. Pathogenic variants in COL2A1 causing Stickler syndrome usually result in haploinsufficiency of the protein, whereas pathogenic variants of type XI collagen more usually exert dominant negative effects. The severity of the disease phenotype is thus dependent on the location and nature of the mutation, as well as the normal developmental role of the respective protein.

Successful non-surgical treatment of pseudomonas choroidal abscess in cystic fibrosis with previous double lung transplantation.

Pseudomonas aeruginosa choroidal abscess is a rare condition which tends to affect patients with cystic fibrosis (CF) who have undergone double lung transplantation. Various surgical treatment strategies have been described but almost universally have had a dismal prognosis. We present a case of pseudomonas choroidal abscess in a CF patient with previous double lung transplantation who was managed with medical treatment, with intravitreal and systemic antibiotics, without surgical intervention, which led to successful resolution of the choroidal abscess, preservation of the eye and retention of vision.

Comparative Propensity Matched Outcomes in Severe COVID-19 Respiratory Failure-Extracorporeal Membrane Oxygenation or Maximum Ventilation Alone.

OBJECTIVE: Does extracorporeal membrane oxygenation (ECMO) improve outcomes in ECMO-eligible patients with COVID-19 respiratory failure compared to maximum ventilation alone (MVA)? SUMMARY BACKGROUND DATA: ECMO is beneficial in severe cases of respiratory failure when mechanical ventilation is inadequate. Outcomes for ECMO-eligible COVID-19 patients on MVA have not been reported. Consequently, a direct comparison between COVID-19 patients on ECMO and those on MVA has not been established. METHODS: A total of 3406 COVID-19 patients treated at two major medical centers in Chicago were studied. One hundred ninety-five required maximum ventilatory support, and met ECMO eligibility criteria. Eighty ECMO patients were propensity matched to an equal number of MVA patients using detailed demographic, physiological, and comorbidity data. Primary outcome was survival and disposition at discharge. RESULTS: Seventy-one percent of patients were decannulated from ECMO. Mechanical ventilation was discontinued in 75% ECMO and 16% MVA patients. Twenty-five percent of patients in the ECMO arm expired, 21% while on ECMO, compared with 74% in the MVA cohort. Mortality was significantly lower across all age and BMI groups in the ECMO arm. Sixty-eight percent ECMO and 26% MVA patients were discharged from the hospital. Fewer ECMO patients required long-term rehabilitation. Major complications such as septic shock, ventilator associated pneumonia, inotropic requirements, acute liver and kidney injuries are less frequent among ECMO patients. CONCLUSIONS: ECMO-eligible patients with severe COVID-19 respiratory failure demonstrate a 3-fold improvement in survival with ECMO. They are also in a better physical state at discharge and have lower overall complication rates. As such, strong consideration should be given for ECMO when mechanical ventilatory support alone becomes insufficient in treating COVID-19 respiratory failure.

Successful use of a novel dynamic rigidizing overtube in a patient with looping during colonoscopy.

Video 1This video is our description of use of the novel dynamic rigidizing overtube in a challenging colonoscopy case in which looping was causing significant bradycardia and inability to advance the colonoscope to the cecum. The rigidizing overtube, through sequential cycles of its flexible and rigidized state, allowed for easy movement of the colonoscope to the cecum.

Stickler Syndrome: Airway Complications in a Case Series of 502 Patients.

BACKGROUND: Patients with Stickler syndrome often require emergency surgery and are often anesthetized in nonspecialist units, typically for retinal detachment repair. Despite the occurrence of cleft palate and Pierre-Robin sequence, there is little published literature on airway complications. Our aim was to describe anesthetic practice and complications in a nonselected series of Stickler syndrome cases. To our knowledge, this is the largest such series in the published literature. METHODS: We retrospectively identified patients with genetically confirmed Stickler syndrome who had undergone general anesthesia in a major teaching hospital, seeking to identify factors that predicted patients who would require more than 1 attempt to correctly site an endotracheal tube (ETT) or supraglottic airway device (SAD). Patient demographics, associated factors, and anesthetic complications were collected. Descriptive statistical analysis and logistic regression modeling were performed. RESULTS: Five hundred and twoanesthetic events were analyzed. Three hundred ninety-five (92.7%) type 1 Stickler and 63 (96.9%) type 2 Stickler patients could be managed with a single attempt of passing an ETT or SAD. Advanced airway techniques were required on 4 occasions, and we report no major complications. On logistic regression, modeling receding mandible (P = .0004) and history of cleft palate (P = .0004) were significantly associated with the need for more than 1 attempt at airway manipulation. CONCLUSIONS: The majority of Stickler patients can be anesthetized safely with standard management. If patients have a receding mandible or history of cleft, an experienced anesthetist familiar with Stickler syndrome should manage the patient. We recommend that patients identified to have a difficult airway wear an alert bracelet.

Auditory dysfunction in type 2 Stickler Syndrome.

PURPOSE: To present the extent and site of lesion of auditory dysfunction in a large cohort of individuals with type 2 Stickler Syndrome. Type 2 Stickler Syndrome results from a mutation in the gene coding for α-1 type XI pro-collagen, which has been identified in the human vitreous, cartilage and the cochlea of the mouse. The condition is characterised by classic ocular abnormalities, auditory dysfunction, osteoarthropathy and oro-facial dysplasia. METHODS: This is a population study which used a combination of audiometric, tympanometric, and self-report measures on a series of 65 individuals (mean age 29.2 years, range 3-70, female 63.1%) with genetically confirmed type 2 Stickler Syndrome. RESULTS: Hearing impairment was identified in at least one ear for 69% of individuals. Analysis against age-matched normative data showed that reduced hearing sensitivity was present across all test frequencies. Sensorineural hearing loss was most common (77% of ears), with conductive (3%), mixed (7%) and no hearing loss (13%), respectively. The proportion of hypermobile tympanic membranes (24%) was less than previously documented in type 1 Stickler Syndrome. When present, this appears to arise as a direct result of collagen abnormalities in the middle ear. Self-report measures of speech and spatial hearing in sound were comparable to a non-syndromic cohort with similar audiometric thresholds. CONCLUSIONS: Auditory impairment in type 2 Stickler Syndrome is predominantly associated with cochlear hearing loss of varying severities across affected individuals. The impact on hearing thresholds can be seen across the frequency range, suggesting a contribution of defective collagen throughout the cochlea. Self-report questionnaires showed that difficulties understanding speech, and spatial information in sound (such as that used for localisation), were worse than a young, normal-hearing population but comparable to a non-syndromic cohort with similar audiometric thresholds. Therefore, it is likely that hearing loss in type 2 Stickler Syndrome arises in the auditory periphery, without significant central processing deficits.

Assessing bulk emulsification at the silicone oil - saline solution interface in a 3D model of the eye.

PURPOSE: Emulsification of silicone oil (SiOil) in a vitrectomized eye was investigated using a 3D model of the vitreous cavity to test the hypothesis that oil droplet formation arises from the breakdown of the bulk SiOil-aqueous interface during eye saccadic movement. METHODS: Round bottom flasks filled with SiOil and a saline phase modelled the vitrectomized SiOil-filled eye. A stepper motor imposed saccadic movements and the oil/aqueous interface was monitored with digital cameras. A range of SiOil viscosities, flask diameters, motion scenarios and levels of fill were studied. Estimates of velocity profiles in the fluid on the equatorial plane of a sphere subject to saccadic motion were obtained from an analytical solution to the Navier-Stokes equations. RESULTS: Interfacial waves were observed at saccadic motions with higher acceleration, amplitude and frequency. Low interfacial tension between the two fluids, lower oil viscosity and smaller level of SiOil fill all promoted large deformations of the interface. No droplets were formed at the bulk SiOil-aqueous interface. However, formation and detachment of oil droplets were observed at the three-phase contact line under certain conditions. CONCLUSIONS: The stresses generated at the liquid-liquid interface are not large enough to form droplets in the bulk region for conditions representative of these in the eye. Bulk emulsification of the SiOil, reported as the main formation mechanism by some workers, is not responsible for droplet formation in a vitrectomized SiOil-filled eye set-up. This result confirms recent finding on droplet formation driven by a surface emulsification mechanism.

Therapeutic and diagnostic advances in Stickler syndrome.

The Stickler syndromes are the leading cause of inherited retinal detachment and the most common cause of rhegmatogenous retinal detachment in childhood. The clinical and molecular genetic spectrum of this connective tissue disorder is discussed in this article, emphasising the key role the ophthalmologist has to play in the identification, diagnosis and prevention of blindness in the increasingly widely recognised sub-groups with ocular-only (or minimal systemic) involvement. Without diagnosis and prophylaxis in such high-risk subgroups, these patients are at high risk of Giant Retinal Tear detachment and blindness, especially in the paediatric population, where late or second eye involvement is common. Initially considered a monogenic disorder, there are now known to be at least 11 distinct phenotypic subgroups in addition to allied connective tissue disorders that can present to the clinician as part of the differential diagnosis. Plain language summary: Treatment and diagnostic advances in Stickler syndrome The Stickler syndromes are a group of related connective tissue disorders that are associated with short-sight and a very high risk of blindness from detachment of the retina - the light sensitive film at the back of the eye. Other features include cleft palate, deafness and premature arthritis. It is the most common cause of retinal detachment in children and the most common cause of familial or inherited retinal detachment. In contrast to most other forms of blinding genetic eye disease, blindness from retinal detachment in Stickler syndrome is largely avoidable with accurate diagnosis and prophylactic (preventive) surgery. Recent advances in the understanding of the genetic causes of Stickler syndrome mean that the diagnosis can now be confirmed in over 95% of cases and, most importantly, the patient's individual risk of retinal detachment can be graded. Preventative surgery is hugely effective in reducing the incidence of retinal detachment in those patients shown to be at high risk. NHS England have led the way in the multidisciplinary care for patients with Stickler syndrome by launching a highly specialist service that has been free at point of care to all NHS patients in England since 2011 (https://www.england.nhs.uk/commissioning/spec-services/highly-spec-services, www.vitreoretinalservice.org).

Bone morphogenetic protein 4 (BMP4) loss-of-function variant associated with autosomal dominant Stickler syndrome and renal dysplasia.

Stickler syndrome is a genetic disorder that can lead to joint problems, hearing difficulties and retinal detachment. Genes encoding collagen types II, IX and XI are usually responsible, but some families have no causal variant identified. We investigate a variant in the gene encoding growth factor BMP4 in a family with Stickler syndrome with associated renal dysplasia. Next generation sequencing of the coding region of COL2A1, COL11A1 and a panel of genes associated with congenital anomalies of the kidney and urinary tract (CAKUT) was performed. A novel heterozygous BMP4 variant causing a premature stop codon, c. 130G>T, p.(Gly44Ter), which segregated with clinical features of Stickler syndrome in multiple family members, was identified. No variant affecting gene function was detected in COL2A1 or COL11A1. Skin fibroblasts were cultured with and without emetine, and the mRNA extracted and analysed by Sanger sequencing to assess whether the change was causing nonsense-mediated decay. Nonsense-mediated decay was not observed from the extracted BMP4 mRNA. BMP4 is a growth factor known to contribute to eye development in animals, and gene variants in humans have been linked to microphthalmia/anophthalmia as well as CAKUT. The variant identified here further demonstrates the importance of BMP4 in eye development. This is the first report of a BMP4 DNA variant causing Stickler syndrome, and we suggest BMP4 be added to standard diagnostic gene panels for this condition.

Surgical treatment for a case of coronary steal from a traumatic coronary artery-cameral fistula after blunt cardiac injury.

INTRODUCTION: Blunt cardiac trauma covers a spectrum of injuries from clinically insignificant myocardial contusions to lethal ruptures of cardiac valves and chambers. Traumatic coronary artery-cameral fistulas (TCAF) are a rare sequelae of blunt chest trauma. CASE PRESENTATION: A 53-year-old male developed a TCAF after a motor vehicle collision. He was found on admission to be in cardiogenic shock with an elevated troponin and intermittent bifascicular block. An echocardiogram revealed hypokinesis of the mid-anteroseptal myocardium with an ejection fraction of 50%. Cardiac catheterization revealed a pseudoaneurysm of the left anterior descending artery (LAD) with a fistulous connection to the right ventricle, shown to be associated with reversible anterior wall ischemia from distal LAD coronary steal phenomenon on a nuclear perfusion scan. Given the ischemic burden, he was treated with operative revascularization via a single vessel coronary artery bypass graft (CABG) using the left internal mammary artery to LAD. DISCUSSION: Early repair of TCAF can halt the progression of complications like left-to-right shunting, pulmonary hypertension, and heart failure. The two best described operative approaches to surgical closure of the fistula are either via external ligation or direct repair from within the recipient chamber, possibly with bypass grafting distal to the fistula site. Transcatheter closure and conservative management has been described for select patients with iatrogenic fistulas in recent literature. CONCLUSION: High levels of clinical suspicion are necessary for the early detection and intervention of TCAF. Surgical or transcatheter interventions including fistula ligation and CABG can prevent later complications of heart failure.

Drains and Blushes: A Case of Impaired Venous Drainage Mimicking Pulmonary Torsion.

A 47-year-old woman underwent elective right upper lobectomy with pneumopexy for adenocarcinoma. On postoperative day 2, she had tachycardia, and her chest radiograph, bronchoscopy, and computed tomography chest scan were suspicious for pulmonary torsion. She underwent emergent thoracotomy, and the right middle lobe was not torsed; it was purple, engorged, and not ventilated. The patient did well after right middle lobectomy. We suspect compromised middle lobe pulmonary venous drainage due to angulation after compensatory expansion. This uncommon phenomenon has not been described previously. High suspicion for pulmonary torsion and treatment led to avoidance of complications such as infection, gangrene, infarction, thromboembolism, and death.

The Evolution of Teleophthalmology Programs in the United Kingdom: Beyond Diabetic Retinopathy Screening.

Modern ophthalmic practice in the United Kingdom is faced by the challenges of an aging population, increasing prevalence of systemic pathologies with ophthalmic manifestations, and emergent treatments that are revolutionary but dependent on timely monitoring and diagnosis. This represents a huge strain not only on diagnostic services but also outpatient management and surveillance capacity. There is an urgent need for newer means of managing this surge in demand and the socioeconomic burden it places on the health care system. Concurrently, there have been exponential increases in computing power, expansions in the strength and ubiquity of communications technologies, and developments in imaging capabilities. Advances in imaging have been not only in terms of resolution, but also in terms of anatomical coverage, allowing new inferences to be made. In spite of this, image analysis techniques are still currently superseded by expert ophthalmologist interpretation. Teleophthalmology is therefore currently perfectly placed to face this urgent and immediate challenge of provision of optimal and expert care to remote and multiple patients over widespread geographical areas. This article reviews teleophthalmology programs currently deployed in the United Kingdom, focusing on diabetic eye care but also discussing glaucoma, emergency eye care, and other retinal diseases. We examined current programs and levels of evidence for their utility, and explored the relationships between screening, teleophthalmology, disease detection, and monitoring before discussing aspects of health economics pertinent to diabetic eye care. The use of teleophthalmology presents an immense opportunity to manage the steadily increasing demand for eye care, but challenges remain in the delivery of practical, viable, and clinically proven solutions.

Treatment of chronic HCV with sofosbuvir and simeprevir in patients with cirrhosis and contraindications to interferon and/or ribavirin.

OBJECTIVES: Patients with chronic hepatitis C virus (HCV) and cirrhosis are in critical need of treatment that is both effective and tolerable. The combination of simeprevir (SMV), a protease inhibitor, and sofosbuvir (SOF), a polymerase inhibitor, without peginterferon and/or ribavirin (PEGINF/RBV) has been shown to achieve sustained virologic response (SVR) exceeding 90% in patients with HCV genotype 1 with prior nonresponse and/or cirrhosis. The present report describes the efficacy of SMV and SOF in patients with cirrhosis, prior or current hepatic decompensation, and other contraindications to PEGINF/RBV. METHODS: A total of 120 consecutive patients with cirrhosis and contraindications to PEGINF/RBV were treated with SMV and SOF for 12 weeks. The primary end point was SVR at 12 weeks after the completion of treatment. RESULTS: The mean age of the cohort was 60 years; 63% were male, 48% were Caucasian, 44% were African American, 69% were of genotype 1A, 49% were treatment naïve, 96% were interleukin-28B non-CC, 33% were of Child class B or C, and 25% had prior hepatic decompensation. The SVR by intention-to-treat was 81% with a relapse rate of 14%. The SVR by per-protocol analysis was 87% with a relapse rate of 13%. The only baseline factor associated with SVR by multifactor analysis was Child class. SVR in patients with Child class A, B, and C was 87, 77, and 67%, respectively. Eleven percent of the patients developed severe adverse events, which included sepsis (two), variceal bleeding (two), hepatocellular carcinoma (two), and hyperbilirubinemia (eight). One of the patients with sepsis died. Two patients developed relapse more than 12 weeks after stopping SMV and SOF. CONCLUSIONS: The combination of SMV and SOF achieves high rates of SVR in patients with advanced cirrhosis but is lower with worsening Child class.

Moving from data collection to application: a systematic literature review of surgical capacity assessments and their applications.

BACKGROUND: Over the past decade, assessments of surgical capacity in low- and middle-income countries (LMICs) have contributed to our understanding of barriers to the delivery of surgical services in a number of countries. It is yet unclear, however, how the findings of these assessments have been applied and built upon within the published literature. METHODS: A systematic literature review of surgical capacity assessments in LMICs was performed to evaluate current levels of understanding of global surgical capacity and to identify areas for future study. A reverse snowballing method was then used to follow-up citations of the identified studies to assess how this research has been applied and built upon in the literature. RESULTS: Twenty-one papers reporting the findings of surgical capacity assessments conducted in 17 different LMICs in South Asia, East Asia and Pacific, Latin America and the Caribbean, and sub-Saharan Africa were identified. These studies documented substantial deficits in human resources, infrastructure, equipment, and supplies. Only seven additional papers were identified which applied or built upon the studies. Among these, capacity assessment findings were most commonly used to develop novel tools and intervention strategies, but they were also used as baseline measurements against which updated capacity assessments were compared. CONCLUSIONS: While the global surgery community has made tremendous progress in establishing baseline values of surgical capacity in LMICs around the world, further work is necessary to build upon and apply the foundational knowledge established through these efforts. Capacity assessment data should be coordinated and used in ongoing research efforts to monitor and evaluate progress in global surgery and to develop targeted intervention strategies. Intervention strategy development may also be further incorporated into the evaluation process itself.