Persistent Cranial Defects After Endoscopic Sagittal Synostosis Surgery.

INTRODUCTION: Incomplete cranial ossification is a rare complication of calvarial-vault remodeling for sagittal synostosis often requiring reoperation. Studies show an incidence ranging from 0.5% to 18%. METHODS: Infants with sagittal synostosis who underwent endoscopic sagittal synostectomy and barrel stave osteotomies with postoperative orthotic helmeting between 2003 and 2021 were included with minimum follow-up until the completion of helmeting. RESULTS: Of 90 patients, 86 met inclusion; 3 had defects (3.5%). Patients with and without cranial defects had no difference in age of surgery (113 versus 131 d), duration helmeting (6.6 versus 7.0 mo), or perioperative/postoperative complications. Two underwent reoperation for recurrence. Patients with cranial defects manifested the evidence of developmental concerns more than patients without (100% versus 16.9%).The average cranial defect size was 19.33 cm 2 and age at surgery 4.29 years. All were managed with cranial particulate bone grafting with addition of bone matrix and SonicWeld plate. The first had 6×6 cm posterior defect requiring cranioplasty at 4.86 years with excellent healing. The second had a 3×6 cm posterior and 1×1 cm anterior defect, underwent cranioplasty at 4.14 years with persistent 4×6 defect, requiring repeat cranioplasty at 5.3 years. The third had a 3×5 cm posterior defect and underwent cranioplasty at 3.88 years with continued defect, planning for repeat intervention. CONCLUSIONS: This is the largest documented series of reoperations for incomplete ossification after endoscopic sagittal synostectomy with postoperative helmet treatment. The authors report a 3.5% rate of cranial defects, managed with bone grafting, bone matrix, and absorbable plates. Patients with poor ossification may have a propensity toward developmental concerns.

Neosagittal Suture Formation after Endoscopic Sagittal Strip Craniectomy: A Case Report and Literature Review.

The fate of the excised synostotic suture in craniosynostosis remains relatively understudied. The purpose of this report is to describe a case of neosagittal suture formation following endoscopic excision of a pathology-proven synostotic suture, with CT demonstration of complete reossification in the areas adjacent to the neosagittal suture. We additionally review the existing literature on neosuture formation that has been published over the past 50 years. We conclude that continued investigation is warranted, both through histological comparison of normal and neosutures and through studies to determine clinical risk factors, as this may improve our understanding of the underlying mechanism of pathologic premature suture fusion in craniosynostosis.

Endoscopic Spring-Mediated Distraction for Unilambdoid Craniosynostosis.

BACKGROUND: Craniosynostosis treatment modalities have changed over time. These have included open calvarial remodeling, suturectomy with helmet molding, hand-powered distraction devices, and spring-mediated distraction. Implantable springs were first described for their use in treatment of craniosynostosis in 1998 (Lauritzen et al, Plast Reconstr Surg 121;2008:545-554). They have been used for the correction of craniosynostosis involving single and multiple sutures and have been placed through both endoscopic and open approaches. Their use for correction of lambdoid synostosis has been previously only described using an open approach (Arnaud et al, Child Nerv Syst 28;2012:1545-1549). The senior author has performed spring-mediated distraction for treating unilambdoid craniosynostosis using an endoscopic approach, which is described below and has not previously been reported by other authors. METHODS: A retrospective analysis of our series of endoscopic unilambdoid synostosis repairs is included in this article. Patients were analyzed based on patient characteristics, operative details, and outcomes. The operation commences by approaching the lambdoid suture endoscopically through a 2- to 3-cm incision lateral to the lambdoid suture. Burr holes are placed on either side of the suture and a suturectomy is performed. Springs are bent preoperatively to a predetermined force. Two springs are placed across the suturectomy defect and the skin is closed. The patient is monitored for improvement in head shape and cranial X-rays are performed to measure the degree of distraction. RESULTS: Seven patients underwent endoscopic spring-mediated distraction for unilambdoid craniosynostosis. The average age at the time of operation was 9.4 months. The median force of each spring placed was 7.0 N. The median length of hospital stay after spring placement was 2 days. Springs were removed at 5.6 months on average. Five patients had X-rays immediately after placement and prior to removal. Each spring expanded an average distance of 15.3 mm. There were no surgical complications. Three patients had both preoperative and postoperative computed tomography scans available. The angle of the cranial base, calculated by comparing foramen magnum to cribriform plate angles, improved 5.8° (12.3 preoperatively to 6.6 postoperatively). CONCLUSION: Endoscopic spring-mediated distraction is a safe and effective method of treatment for unilambdoid craniosynostosis. The series represents the largest experience with this technique. The approach can be considered in all patients with unilambdoid synostosis given the efficacious improvement in vault remodeling, low patient morbidity, short operating time, and minimal inpatient stay.

Live Vaccines Against Plasmodium Preerythrocytic Stages.

Vaccines that target the preerythrocytic phase of malaria hold great promise as elimination tools since they are the sole vaccines that can achieve sterile protection against a challenge. This chapter focuses on preerythrocytic stage vaccines based on live attenuated parasites. It first summarizes the main conclusions that have emerged from studies in rodents, which compared various parasite attenuation methods, and then presents the vaccination regimens that are currently being tested in humans.

The Pushback Pharyngeal Flap: An 18-Year Experience.

BACKGROUND: The pharyngeal flap is one of the oldest and most popular techniques for correction of velopharyngeal insufficiency. The authors describe a large series using a technique that combines a pharyngeal flap with a palate pushback to avoid common causes of operative failure while restoring the velopharyngeal mechanism. METHODS: A retrospective cohort study was performed of patients who underwent a pushback pharyngeal flap by a single surgeon from 2000 to 2017. All patients had a preoperative nasoendoscopy diagnostic of velopharyngeal insufficiency. Operative technique involved elevation of the hard palate mucosa through a retroalveolar incision, passage of the flap through the nasopharyngeal mucosa opening, and inset with sutures through the hard palate mucosa. RESULTS: There were 40 patients with a median age of 9.7 years. Preoperative closure patterns were predominately coronal (85.7 percent), with poor posterior wall motion and an average gap size of 27.5 mm. Postoperative complications included flap dehiscence (n = 1), transient dysphagia (n = 2), obstructive sleep apnea (n = 4), and a palatal fistula and/or persistent velopharyngeal insufficiency that required further surgery (n = 6). At an average of 2.5 years postoperatively, 91.7 percent of patients achieved adequate velopharyngeal function, with significant improvements in the majority of speech metrics (p < 0.001). CONCLUSIONS: The pushback pharyngeal flap is a safe and effective technique for treatment of velopharyngeal insufficiency. Advantages include high, secure inset with prevention of palatal scar contracture and shortening. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Single Stage Repair of #30 Facial Cleft with Bone Morphogenic Protein.

Tessier #30 clefts (median mandibular clefts) represent a spectrum of deformities ranging from a minor cleft in the lower lip to complete clefts of the mandible involving the tongue, lower lip, hyoid bone, thyroid cartilages, and manubrium. Various techniques have been used to address these problems; the most common procedure involving 2 stages: an initial correction of the soft tissue followed by closure of the mandibular cleft at a later date using bone grafting. This approach was subsequently reduced to a single operation, but still required harvesting of autologous bone graft. Here, we describe a modified single-stage operation using human recombinant bone morphogenic protein, avoiding bone graft harvest and allowing for simultaneous treatment of bone and soft tissue.

Isolated Intraorbital Frontosphenoidal Synostosis.

Unilateral anterior plagiocephaly is most commonly the result of deformational plagiocephaly or unilateral coronal synostosis, a premature fusion of the frontoparietal suture. However, other sutures within the coronal ring have been implicated in producing anterior cranial asymmetries. These fusions can occur in isolation or in concert with adjacent sutures. The frontosphenoidal suture is one such suture within the coronal ring that has been involved both concomitantly with and independently of frontoparietal suture fusion. Although isolated frontosphenoidal synostosis has been presented previously in the literature, these reports include patients with fusion of the extraorbital portion of the frontosphenoidal suture. This clinical report presents the first clearly documented patient of isolated frontosphenoidal synostosis that occurs entirely within the intraorbital region.The patient presented to Plastic Surgery Clinic at 3 months of age with left frontal flattening, supraorbital rim retrusion, and temporal bulging that was noted soon after birth. Computed tomography analysis revealed an isolated fusion of the greater and lesser wings of the sphenoid bone to the frontal bone on the left side. The patient had no family history of cranial anomalies and genetic testing was negative for mutations. The infant was treated with a cranial orthotic for 3 months, underwent open fronto-orbital advancement and cranial vault remodeling at 6 months, and continued wearing a cranial orthotic for another 4.5 months. Following surgical and orthotic treatment, the patient achieved a satisfactory result.

Immunological memory to blood-stage malaria infection is controlled by the histamine releasing factor (HRF) of the parasite.

While most subunit malaria vaccines provide only limited efficacy, pre-erythrocytic and erythrocytic genetically attenuated parasites (GAP) have been shown to confer complete sterilizing immunity. We recently generated a Plasmodium berghei (PbNK65) parasite that lacks a secreted factor, the histamine releasing factor (HRF) (PbNK65 hrfΔ), and induces in infected mice a self-resolving blood stage infection accompanied by a long lasting immunity. Here, we explore the immunological mechanisms underlying the anti-parasite protective properties of the mutant PbNK65 hrfΔ and demonstrate that in addition to an up-regulation of IL-6 production, CD4+ but not CD8+ T effector lymphocytes are indispensable for the clearance of malaria infection. Maintenance of T cell-associated protection is associated with the reduction in CD4+PD-1+ and CD8+PD-1+ T cell numbers. A higher number of central and effector memory B cells in mutant-infected mice also plays a pivotal role in protection. Importantly, we also demonstrate that prior infection with WT parasites followed by a drug cure does not prevent the induction of PbNK65 hrfΔ-induced protection, suggesting that such protection in humans may be efficient even in individuals that have been infected and who repeatedly received antimalarial drugs.

Vermilion Only Cross-lip Flap for Treating Whistle Deformity in Secondary Bilateral Cleft Lip Repair.

Bilateral cleft lip repairs can result in various secondary deformities. One more commonly seen deformity, the whistle deformity, is characterized by a reduced or absent tubercle, orbicularis muscle diastasis, and abnormalities of the philtrum with notched appearance of cupid's bow. Various techniques have been described to address these problems. One common procedure is the lip-switch flap originally described by Abbe in 1898, which has been modified by various surgeons. In these procedures, lower lip vermilion, mucosa, orbicularis, and lip skin are transposed to the upper lip on a pedicle that is later divided. In all these variations of the lip-switch procedure, the transposed tissue involves the entire lower lip skin-leaving large, unsightly, and unnecessary scars. It also brings abnormal tissue into the philtrum further distorting the upper lip. A modified cross-lip flap that is limited to the taking only mucosa, vermilion, and orbicularis is feasible and provides an optimal reconstruction without compromising additional tissue.

Protection against malaria in mice is induced by blood stage-arresting histamine-releasing factor (HRF)-deficient parasites.

Although most vaccines against blood stage malaria in development today use subunit preparations, live attenuated parasites confer significantly broader and more lasting protection. In recent years, Plasmodium genetically attenuated parasites (GAPs) have been generated in rodent models that cause self-resolving blood stage infections and induce strong protection. All such GAPs generated so far bear mutations in housekeeping genes important for parasite development in red blood cells. In this study, using a Plasmodium berghei model compatible with tracking anti-blood stage immune responses over time, we report a novel blood stage GAP that lacks a secreted factor related to histamine-releasing factor (HRF). Lack of HRF causes an IL-6 increase, which boosts T and B cell responses to resolve infection and leave a cross-stage, cross-species, and lasting immunity. Mutant-induced protection involves a combination of antiparasite IgG2c antibodies and FcγR(+) CD11b(+) cell phagocytes, especially neutrophils, which are sufficient to confer protection. This immune-boosting GAP highlights an important role of opsonized parasite-mediated phagocytosis, which may be central to protection induced by all self-resolving blood stage GAP infections.

Development of Volunteer International Craniofacial Surgery Missions: The Komedyplast Protocol.

Volunteer surgical missions to provide cleft care to patients in developing countries has been done successfully for a number of years. Similar missions that provide craniofacial surgery introduce a dramatic step up in complexity. While articles have addressed protocols for the safe delivery of cleft care around the world, little has been written on volunteer craniofacial surgical missions. Komedyplast was established in March 2001 as a 501c(3) nonprofit organization to provide craniofacial surgical care to underserved populations and educate local surgeons in craniofacial principles. During 9 annual missions, the organization has provided surgical care to more than 150 patients with various complex, congenital, craniofacial conditions. The article addresses important safeguards that have been implemented to maximize safety and minimize risk.

Plasmodium berghei histamine-releasing factor favours liver-stage development via inhibition of IL-6 production and associates with a severe outcome of disease.

Plasmodium spp., which causes malaria, produces a histamine-releasing factor (HRF), an orthologue of mammalian HRF. Histamine-releasing factor produced by erythrocytic stages of the parasite is thought to play a role in the pathogenesis of severe malaria. Here, we show in a rodent model that HRF is not important during the erythrocytic but pre-erythrocytic phase of infection, which mainly consists in the transformation in the liver of the mosquito-injected parasite form into the erythrocyte-infecting form. Development of P. berghei ANKA cl15cy1 liver stages lacking HRF is impaired and associated with an early rise in systemic IL-6, a cytokine that strongly suppresses development of Plasmodium liver stages. The defect is rescued by injection of anti-IL-6 antibodies or infection in IL-6-deficient mice and parasite HRF is sufficient to decrease IL-6 synthesis, indicating a direct role of parasite HRF in reducing host IL-6. The target cells modulated by HRF for IL-6 production at early time points during liver infection are neutrophils. Parasite HRF is thus used to down-regulate a cytokine with anti-parasite activity. Our data also highlight the link between a prolonged transition from liver to blood-stage infection and reduced incidence of experimental cerebral malaria.

ZIPCO, a putative metal ion transporter, is crucial for Plasmodium liver-stage development.

The malaria parasite, Plasmodium, requires iron for growth, but how it imports iron remains unknown. We characterize here a protein that belongs to the ZIP (Zrt-, Irt-like Protein) family of metal ion transport proteins and have named ZIP domain-containing protein (ZIPCO). Inactivation of the ZIPCO-encoding gene in Plasmodium berghei, while not affecting the parasite's ability to multiply in mouse blood and to infect mosquitoes, greatly impairs its capacity to develop inside hepatocytes. Iron/zinc supplementation and depletion experiments suggest that ZIPCO is required for parasite utilization of iron and possibly zinc, consistent with its predicted function as a metal transporter. This is the first report of a ZIP protein having a crucial role in Plasmodium liver-stage development, as well as the first metal ion transporter identified in Plasmodium pre-erythrocytic stages. Because of the drastic dependence on iron of Plasmodium growth, ZIPCO and related proteins might constitute attractive drug targets to fight against malaria.

A cysteine protease inhibitor of plasmodium berghei is essential for exo-erythrocytic development.

Plasmodium parasites express a potent inhibitor of cysteine proteases (ICP) throughout their life cycle. To analyze the role of ICP in different life cycle stages, we generated a stage-specific knockout of the Plasmodium berghei ICP (PbICP). Excision of the pbicb gene occurred in infective sporozoites and resulted in impaired sporozoite invasion of hepatocytes, despite residual PbICP protein being detectable in sporozoites. The vast majority of these parasites invading a cultured hepatocyte cell line did not develop to mature liver stages, but the few that successfully developed hepatic merozoites were able to initiate a blood stage infection in mice. These blood stage parasites, now completely lacking PbICP, exhibited an attenuated phenotype but were able to infect mosquitoes and develop to the oocyst stage. However, PbICP-negative sporozoites liberated from oocysts exhibited defective motility and invaded mosquito salivary glands in low numbers. They were also unable to invade hepatocytes, confirming that control of cysteine protease activity is of critical importance for sporozoites. Importantly, transfection of PbICP-knockout parasites with a pbicp-gfp construct fully reversed these defects. Taken together, in P. berghei this inhibitor of the ICP family is essential for sporozoite motility but also appears to play a role during parasite development in hepatocytes and erythrocytes.

Local immune response to injection of Plasmodium sporozoites into the skin.

Malarial infection is initiated when the sporozoite form of the Plasmodium parasite is inoculated into the skin by a mosquito. Sporozoites invade hepatocytes in the liver and develop into the erythrocyte-infecting form of the parasite, the cause of clinical blood infection. Protection against parasite development in the liver can be induced by injection of live attenuated parasites that do not develop in the liver and thus do not cause blood infection. Radiation-attenuated sporozoites (RAS) and genetically attenuated parasites are now considered as lead candidates for vaccination of humans against malaria. Although the skin appears as the preferable administration route, most studies in rodents, which have served as model systems, have been performed after i.v. injection of attenuated sporozoites. In this study, we analyzed the early response to Plasmodium berghei RAS or wild-type sporozoites (WTS) injected intradermally into C57BL/6 mice. We show that RAS have a similar in vivo distribution to WTS and that both induce a similar inflammatory response consisting of a biphasic recruitment of polymorphonuclear neutrophils and inflammatory monocytes in the skin injection site and proximal draining lymph node (dLN). Both WTS and RAS associate with neutrophils and resident myeloid cells in the skin and the dLN, transform inside CD11b(+) cells, and induce a Th1 cytokine profile in the dLN. WTS and RAS are also similarly capable of priming parasite-specific CD8(+) T cells. These studies delineate the early and local response to sporozoite injection into the skin, and suggest that WTS and RAS prime the host immune system in a similar fashion.

The role of MACPF proteins in the biology of malaria and other apicomplexan parasites.

Apicomplexans are eukaryotic parasites of major medical and veterinary importance. They have complex life cycles through frequently more than one host, interact with many cell types in their hosts, and can breach host cell membranes during parasite traversal of, or egress from, host cells. Some of these parasites make a strikingly heavy use of the pore-forming MACPF domain, and encode up to 10 different MACPF domain-containing proteins. In this chapter, we focus on the two most studied and medically important apicomplexans, Plasmodium and Toxoplasma, and describe the known functions of their MACPF polypeptide arsenal. Apicomplexan MACPF proteins appear to be involved in a variety of membrane-damaging events, making them an attractive model to dissect the structure-function relationships of the MACPF domain.

Loss of host cell plasma membrane integrity following cell traversal by Plasmodium sporozoites in the skin.

Plasmodium sporozoites are able to migrate through host cells by breaching their plasma membrane and gliding inside their cytoplasm. This migratory activity, called cell traversal (CT), was studied in vivo mainly using mutant sporozoites lacking the ability to wound host cells, and thus to perform CT. However, direct evidence of CT activity in host tissues by wild-type sporozoites remains scarce. Here, we describe a double-wounding assay to dynamically image CT activity in vivo and monitor cell membrane integrity over time. Based on the incorporation kinetics of a first live cell-impermeant dye, propidium iodide, we could determine whether traversed cells repair their wounded membranes or not. A second impermeant dye, SYTOX Green, was used to confirm the transient or the permanent loss of membrane integrity of traversed cells. This assay allowed, for the first time, the direct observation of sporozoites wounding and traversing host skin cells and showed that, while some traversed cells resealed their membrane, most became irreversibly permeable to these live cell-impermeant dyes. In combination with the study of CT-deficient sporozoites and the use of specific host cell markers, this intravital assay will provide the means to identify the nature of the cells traversed by sporozoites and will thus contribute to elucidating the role of CT by apicomplexan parasites in the vertebrate host.

Selective inhibition of USP7.

The deubiquitinating enzyme USP7 is an emerging oncology and antiviral target. Reverdy et al., in this issue of Chemistry & Biology, disclose the first small-molecule inhibitor selective for USP7, which recapitulates its knockdown in cancer cells and hence demonstrates the therapeutic feasibility of USP7 inhibitors.

PK4, a eukaryotic initiation factor 2α(eIF2α) kinase, is essential for the development of the erythrocytic cycle of Plasmodium.

In response to environmental stresses, the mammalian serine threonine kinases PERK, GCN2, HRI, and PKR phosphorylate the regulatory serine 51 of the eukaryotic translation initiation factor 2α (eIF2α) to inhibit global protein synthesis. Plasmodium, the protozoan that causes malaria, expresses three eIF2α kinases: IK1, IK2, and PK4. Like GCN2, IK1 regulates stress response to amino acid starvation. IK2 inhibits development of malaria sporozoites present in the mosquito salivary glands. Here we show that the phosphorylation by PK4 of the regulatory serine 59 of Plasmodium eIF2α is essential for the completion of the parasite's erythrocytic cycle that causes disease in humans. PK4 activity leads to the arrest of global protein synthesis in schizonts, where ontogeny of daughter merozoites takes place, and in gametocytes that infect Anopheles mosquitoes. The implication of these findings is that drugs that reduce PK4 activity should alleviate disease and inhibit malaria transmission.

CO2-based tissue expansion: a study of initial performance in ovine subjects.

BACKGROUND: Tissue expanders are an essential reconstructive surgical tool commonly utilized in two-staged breast reconstruction. The current technology is limited primarily to saline expansion, which can be a long process requiring frequent office visits. Eliminating the need for percutaneous injections could potentially improve the psychological and physical discomfort associated with the expansion process as well as save time and resources for both the patient and surgeon. OBJECTIVES: The authors describe a novel system of gradual, controlled, needle-free expansion. The purpose of the study was to evaluate, prior to clinical use, the in vivo communication between CO(2)-based tissue expanders and their paired handheld dosage controllers and the ability of each expander to reach its intended volume. METHODS: Twelve expanders-three small (400 cm(3)), three medium (650 cm(3)), four large (850 cm(3)), and two full (1100 cm(3))-were implanted in two mature ovines and were expanded daily with CO(2) using 12 paired handheld dosage controllers. Device performance and expansion progress (cm(3)/d) to size-specified volumes were observed and recorded. An on-site veterinarian monitored the animals for signs of distress during and after inflations. After full expansion of the implants, the animals were euthanized and the implants were surgically removed and examined. RESULTS: All 12 paired devices performed to specification, achieving successful expansion, and measured volumes of explanted expanders confirmed expansion to the labeled volume. Expansion to full volume was achieved in all units in Ovine 1 within 13 days and in Ovine 2 within 11 days. Total implantation time was 21 days in Ovine 1 and 12 days in Ovine 2. No adverse events were encountered. CONCLUSIONS: This CO(2)-based tissue expansion system offers a novel and potentially valuable tool for reconstructive surgery. This study demonstrated the in vivo performance of a CO(2)-based tissue expander in an ovine model and merits future clinical research efforts. All tested devices accomplished needle-free expansion with the expanders responding to dosage-controller commands within programmed safety limitations. This system has the potential to expedite expansion through gradual, controlled distention of tissue and to simplify the process for both physician and patient.