Christopher R Forrest

SickKids, Toronto, Ontario, Canada

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Publications (128)259.82 Total impact

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    ABSTRACT: Treacher Collins syndrome is a rare disorder characterized by several orofacial findings including malar deficiency and hypoplastic mandibles. These patients often require a combined orthodontic–orthognathic approach to correct their malocclusion. This is most often characterized by a short posterior vertical height and an anterior open bite. Orthognathic correction often requires Le Fort I and bilateral sagittal split osteotomies. No long-term stability results have been reported after bimaxillary surgery in Treacher Collins patients.
    No preview · Article · Oct 2015 · Journal of Plastic Reconstructive & Aesthetic Surgery

  • No preview · Article · Oct 2015 · Quality of Life Research
  • Susan I Blaser · Nancy Padfield · David Chitayat · Christopher R Forrest
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    ABSTRACT: Abnormal skull shape resulting in craniofacial deformity is a relatively common clinical finding, with deformity either positional (positional plagiocephaly) or related to premature ossification and fusion of the skull sutures (craniosynostosis). Growth restriction occurring at a stenosed suture is associated with exaggerated growth at the open sutures, resulting in fairly predictable craniofacial phenotypes in single-suture non-syndromic pathologies. Multi-suture syndromic subtypes are not so easy to understand without imaging. Imaging is performed to define the site and extent of craniosynostosis, to determine the presence or absence of underlying brain anomalies, and to evaluate both pre- and postoperative complications of craniosynostosis. Evidence for intracranial hypertension may be seen both pre- and postoperatively, associated with jugular foraminal stenosis, sinovenous occlusion, hydrocephalus and Chiari 1 malformations. Following clinical assessment, imaging evaluation may include radiographs, high-frequency US of the involved sutures, low-dose (20-30 mAs) CT with three-dimensional reformatted images, MRI and nuclear medicine brain imaging. Anomalous or vigorous collateral venous drainage may be mapped preoperatively with CT or MR venography or catheter angiography.
    No preview · Article · Sep 2015 · Pediatric Radiology
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    ABSTRACT: Cranio-orbital remodeling aims to correct the dysmorphic skull associated with craniosynostosis. Traditionally, the skull is reconstructed into a shape that is subjectively normal according to the surgeon's perception. We present a novel technique using a mathematical algorithm to define the optimal location for bony osteotomies and to objectively reshape the fronto-orbital bar into an ideal normal skull contour.Using pre-operative computed tomography images, the abnormal skull contour at the frontal-orbital region was obtained for infants planned to undergo cranio-orbital remodeling. The ideal skull shape was derived from an age- and sex-matched normative skull library. For each patient, the mathematical technique of dynamic programming (DP) was applied to compare the abnormal and ideal skull shapes. The DP algorithm identifies the optimal location of osteotomy sites and calculates the objective difference in surface area remaining between the normative and dysmorphic skull shape for each solution applied. By selecting the optimal solution with minimal objective difference, the surgeon is guided to reproducibly recreate the normal skull contour with defined osteotomies.The DP algorithm was applied in 13 cases of cranio-orbital remodeling. Five female and 8 male infants with a mean age of 11 months were treated for craniosynostosis classified as metopic (n = 7), unicoronal (n = 4), or bicoronal (n = 2). The mean OR time was 190.2 min (SD 33.6), mean estimated blood loss 244 cc (SD 147.6), and 10 infants required blood transfusions. Compared with a historical crania-orbital remodeling group treated without application of the algorithm, there was no significant difference in OR time, estimated blood loss, or transfusion rate.This novel technique enables the craniofacial surgeon to objectively reshape the fronto-orbital bar and reproducibly reconstruct a skull shape resembling that of normal infants.
    No preview · Article · Jul 2015 · The Journal of craniofacial surgery
  • Vivek Panchapakesan · Toni Zhong · Christopher R Forrest · Andrea L Pusic · Achilles Thoma

    No preview · Article · Dec 2014
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    ABSTRACT: Objective : To investigate the stability of major versus minor Le Fort I maxillary advancements in unilateral cleft lip and palate (UCLP) patients. Design : A retrospective longitudinal study was undertaken on 30 nonsyndromic UCLP patients treated with the same protocol at The Hospital for Sick Children, Toronto, Canada. Patients were grouped into major and minor movement groups based on planned surgical advancement. Standard lateral cephalometric radiographs were taken preoperatively (T1), immediately postoperatively (T2), and at least 1 year postoperatively (T3). Skeletal and dental variables were measured using cephalometric analysis. Stability was compared between groups using repeated-measures analysis of variance. Linear regression analysis was used to assess the relationship between advancement and relapse for the entire study population. Results : A mean maxillary advancement of 9.8 mm and 4.9 mm was seen for the major (n = 10) and minor (n = 20) movement groups, respectively. The mean skeletal horizontal relapse was 1.8 mm (18%) for the major advancement group and 1.5 mm (31%) for the minor advancement group. There was no significant difference in skeletal horizontal relapse between the groups (P > .05). The correlation coefficient (r) between linear horizontal advancement and relapse was calculated to be .31 (P > .05). Dental horizontal relapse was not significant for either the major or minor groups, and no significant difference was found between the groups (P > .05). Conclusion : Skeletal and dental relapse was found to be unrelated to the amount of maxillary linear advancement using conventional Le Fort I osteotomies in UCLP.
    No preview · Article · Sep 2014 · The Cleft Palate-Craniofacial Journal
  • P.G. Klaiman · C.R. Forrest · J.H. Phillips · S.J. Fischbach

    No preview · Article · Sep 2014 · Journal of Oral and Maxillofacial Surgery

  • No preview · Article · Sep 2014 · Journal of Oral and Maxillofacial Surgery
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    ABSTRACT: Hemifacial microsomia is a hypoplastic disorder of the first and second branchial arches that significantly impacts on the development of the jaws, leading to malocclusion and facial asymmetry. There is little in the literature regarding the application of orthodontic/orthognathic approaches to the correction of these deformities and the stability of the surgical results. To address this, a retrospective chart review of 10 patients with complete orthodontic records and greater than 1 year of follow-up was performed. Posteroanterior cephalograms were assessed by modified Grummons analysis to determine mandibular offset (deviation of the chin point from the skeletal midline) and occlusal cant. These measurements were performed at 3 time points (T1: preoperative, T2: immediate postoperative, T3: follow-up) to elucidate the surgical movement (T2-T1), the postoperative relapse (T3-T2), and the net gain movement (T3-T1). Maxillary movements were quantified, and the occlusal cant was expressed as a ratio between vertical heights of the maxilla at the first molar on each side. One sample t test demonstrated statistically significant surgical movement and net gain. Relapse was statistically insignificant. Repeated-measures analysis of variance demonstrated similar results for chin point position relative to the putative midline. Our results suggest that a combined orthodontic/orthognathic approach at skeletal maturity delivers improved occlusal outcomes in the long term as assessed by chin point deviation and occlusal cant, but secondary surgery rates are higher than those for orthognathic surgery in other patient groups. We advocate limiting surgery to skeletal maturity whenever possible to achieve stable long-term results while limiting morbidity and number of procedures.
    No preview · Article · Jul 2014 · Journal of Craniofacial Surgery
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    ABSTRACT: Purpose To investigate the stability of single piece versus segmental (2-piece) maxillary advancement in unilateral cleft lip and palate (UCLP) patients treated using conventional Le Fort I orthognathic surgery. Methods A retrospective study was undertaken on 30 non-syndromic UCLP patients treated with the same surgical and orthodontic protocol between 2002 and 2011. Standard lateral cephalometric radiographs were taken preoperatively, immediately postoperatively, and at least 1 year postoperatively. Patients were divided into single piece and segmental Le Fort I groups based on planned surgical movement. Postoperative movements were compared between groups using repeated measure analysis of variance. Results The mean skeletal horizontal advancement was 7.3 and 7.5mm in the single piece and segmental groups, respectively. The skeletal horizontal relapse was 1.3mm (18%) for the single piece group and 1.9mm (25%) for the segmental group. The skeletal surgical extrusion was 2.7mm for both groups. The skeletal vertical relapse was 0.6mm (22%) and 1.5mm (56%) for the single piece and segmental groups, respectively. The mean dental horizontal postoperative movement for the single piece group was advancement of 0.4mm and for the segmental group a relapse of 0.2mm (3%). The mean dental vertical relapse was 0.1mm (4%) for the single piece and 0.3mm (11%) for the segmental group. There was no statistically significant difference in relapse between the single and segmental groups for all movements (p>0.05). Conclusion Skeletal and dental relapse was similar between single piece and segmental maxillary advancements using conventional Le Fort I orthognathic surgery in UCLP patients.
    No preview · Article · Jul 2014 · Journal of Oral and Maxillofacial Surgery
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    ABSTRACT: Recent reports of directed reprogramming have raised questions about the stability of cell lineages. Here, we have addressed this issue, focusing upon skin-derived precursors (SKPs), a dermally derived precursor cell. We show by lineage tracing that murine SKPs from dorsal skin originate from mesenchymal and not neural crest-derived cells. These mesenchymally derived SKPs can, without genetic manipulation, generate functional Schwann cells, a neural crest cell type, and are highly similar at the transcriptional level to Schwann cells isolated from the peripheral nerve. This is not a mouse-specific phenomenon, since human SKPs that are highly similar at the transcriptome level can be made from neural crest-derived facial and mesodermally derived foreskin dermis and the foreskin SKPs can make myelinating Schwann cells. Thus, nonneural crest-derived mesenchymal precursors can differentiate into bona fide peripheral glia in the absence of genetic manipulation, suggesting that developmentally defined lineage boundaries are more flexible than widely thought.
    Full-text · Article · Jul 2014 · Stem Cell Reports

  • No preview · Article · Mar 2014 · Plastic & Reconstructive Surgery
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    ABSTRACT: Although symmetry is hailed as a fundamental goal of aesthetic and reconstructive surgery, our tools for measuring this outcome have been limited and subjective. With the advent of three-dimensional photogrammetry, surface geometry can be captured, manipulated, and measured quantitatively. Until now, few normative data existed with regard to facial surface symmetry. Here, we present a method for reproducibly calculating overall facial symmetry and present normative data on 100 subjects. We enrolled 100 volunteers who underwent three-dimensional photogrammetry of their faces in repose. We collected demographic data on age, sex, and race and subjectively scored facial symmetry. We calculated the root mean square deviation (RMSD) between the native and reflected faces, reflecting about a plane of maximum symmetry. We analyzed the interobserver reliability of the subjective assessment of facial asymmetry and the quantitative measurements and compared the subjective and objective values. We also classified areas of greatest asymmetry as localized to the upper, middle, or lower facial thirds. This cluster of normative data was compared with a group of patients with subtle but increasing amounts of facial asymmetry. We imaged 100 subjects by three-dimensional photogrammetry. There was a poor interobserver correlation between subjective assessments of asymmetry (r = 0.56). There was a high interobserver reliability for quantitative measurements of facial symmetry RMSD calculations (r = 0.91-0.95). The mean RMSD for this normative population was found to be 0.80 ± 0.24 mm. Areas of greatest asymmetry were distributed as follows: 10% upper facial third, 49% central facial third, and 41% lower facial third. Precise measurement permitted discrimination of subtle facial asymmetry within this normative group and distinguished norms from patients with subtle facial asymmetry, with placement of RMSDs along an asymmetry ruler. Facial surface symmetry, which is poorly assessed subjectively, can be easily and reproducibly measured using three-dimensional photogrammetry. The RMSD for facial asymmetry of healthy volunteers clusters at approximately 0.80 ± 0.24 mm. Patients with facial asymmetry due to a pathologic process can be differentiated from normative facial asymmetry based on their RMSDs. Diagnostic, II.
    Full-text · Article · Jan 2014 · The Journal of craniofacial surgery
  • Mitchel Seruya · Jenny Tran · Samintharaj Kumar · Christopher R Forrest · David K Chong
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    ABSTRACT: The purpose of this study is 2-fold: (1) to identify computed tomography (CT)-based morphometric parameters that differentiate the normal skull from one with sagittal synostosis and (2) to evaluate correction of sagittal synostosis with extended strip craniectomy and postoperative helmeting based on morphometric parameters. An institutional review board-approved, retrospective review was carried out at the Hospital for Sick Children for all patients who underwent an extended strip craniectomy and postoperative helmeting for sagittal synostosis from 1999 to 2005. Inclusion criteria consisted of patients who underwent a routine craniofacial CT preoperatively and 12 months postoperatively. Craniofacial CT scans of age-matched control subjects were used for preoperative and postoperative comparison. Thirty-nine patients with sagittal synostosis met inclusion criteria. Median age at preoperative CT was 3.0 months. Nine control subjects were identified, with a median age at CT scan of 5.0 months. Patients with sagittal synostosis preoperatively had a significantly longer maximum cranial length, smaller maximum cranial breadth, more acute frontal takeoff and occipital incline angles, lower cephalic index, and an anteriorly positioned vertex. Postoperative CT scans (median, 17.0 months) were compared with 10 control subjects (median, 19.0 months). Patients with sagittal synostosis postoperatively had equivalent maximum cranial breadth, frontal takeoff, and occipital incline angles as compared with controls. Sagittal synostosis patients remained with a significantly longer maximum cranial length, lower cephalic index, and anteriorly positioned vertex. Twelve months following extended strip craniectomy and helmeting for sagittal synostosis, CT-based morphometric analysis demonstrated correction of cranial breadth, frontal bossing, and occipital bulleting. Skull length and vertex position did not fully correct.
    No preview · Article · Jan 2014 · The Journal of craniofacial surgery
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    ABSTRACT: Cranio-orbital reshaping for anterior cranial-vault deformities associated with craniosynostosis traditionally relies on the surgeon's subjective estimate of the shape and appearance of a normal forehead. Computer-aided design/computer-aided manufacture (CAD/CAM) bandeau templates to guide reconstruction were introduced in our centre to eliminate this subjectivity and to effect more reproducible surgical results. The aim of this study was to compare two groups of patients (template, n = 14 vs. no template, n = 23) to measure surgical outcomes. The virtual, computational version of the template was used as an outcome assessment tool. It was used to calculate an intervening area under the curve (AUC) between the normative template and the patient's reconstructed supra-orbital bar on a representative computed tomography (CT) axial section. A comprehensive chart review was conducted of patients in both groups to examine the preoperative and postoperative variables. Based on the analysis performed on the immediate postoperative CT scans, in the template group - as compared to the control, no-template group - the use of the bandeau template led to a greater reduction in AUC (74% vs. 56%, p = 0.016), indicating a better conformity between the reconstructed supra-orbital bar and the ideal, normal bandeau shape. The duration of operation was significantly reduced with the use of the template (212 vs. 258 min, p < 0.001). The application of prefabricated templates in cranio-orbital reshaping is highly useful for accurate preoperative planning; reproducible and efficient intra-operative correction of dysmorphology; and objective surgical outcomes assessment. Therapeutic Level III.
    No preview · Article · Sep 2013 · Journal of Plastic Reconstructive & Aesthetic Surgery
  • A Fattah · D Khechoyan · J.H. Phillips · C.R. Forrest
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    ABSTRACT: Craniofacial fibrous dysplasia is a benign developmental anomaly in which normal bone is replaced by fibro-osseous tissue. The aim of this study was to audit the patient population at a tertiary paediatric centre and report our treatment protocols. A retrospective chart review of all patients with craniofacial fibrous dysplasia treated at the Hospital for Sick Children between 1999 and 2010 was performed. The treatment algorithm used by our centre is presented. A total of 55 patient records were reviewed; 37 patients had sufficient documentation for study; 27 (16 male, 11 female) patients underwent surgery at our institution, of these patients, 26 had post-operative follow up of greater than one year (mean 41 months; median 24 months). Mean age at presentation was 9.9 years (median 10 years) and mean age of surgery was 13 years. Ten patients underwent surgery on the fronto-orbital region, 7 of the calvarium, 2 the skull base and 8 upon tooth-bearing bones. Fourteen cases underwent debulking surgery as their primary therapy whereas 13 patients had complete resection. Nine patients experienced recurrence and all but one case of these occurred in patients that underwent debulking therapy. When age of surgery is considered, total resection and reconstruction or debulking surgery after skeletal maturity has a lower recurrence rate (1/7 cases) than earlier surgery (8/16). Complete resection at any age and debulking surgery once skeletal maturity has been reached may be associated with lower recurrence rates than incomplete resections at an earlier age. Patients with McCune-Albright syndrome may benefit from repeated debulking procedures rather than complex resections and reconstructions.
    No preview · Article · Jul 2013 · Journal of Plastic Reconstructive & Aesthetic Surgery

  • No preview · Article · May 2013 · Plastic & Reconstructive Surgery
  • Karen W.Y. Wong · Christopher R Forrest · Tim E.E. Goodacre · Anne F Klassen
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    ABSTRACT: This article discusses the measurement of outcomes in craniofacial and pediatric plastic surgery, using examples of craniosynostosis and cleft lip and/or palate (CLP). The challenges in measuring the standard outcomes of function, aesthetics, and health-related quality of life are discussed, along with the importance of developing evidence and studying quality improvement in this specialty. The need to define specific and comprehensive goals is discussed with a focus on patient-reported outcomes (PROs). Examples from the development of the CLEFT-Q, a PRO instrument for patients with CLP, are provided to support the need to seek the patient perspective.
    No preview · Article · Apr 2013 · Clinics in plastic surgery
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    ABSTRACT: : In autogenous muscle transplantation, unpredictable complications can cause prolonged ischemia, resulting in ischemia-reperfusion injury. The authors investigated the efficacy and mechanism of nicorandil, a nitrovasodilator and adenosine triphosphate-sensitive potassium channel opener, in inducing perioperative protection of muscle flaps from ischemia-reperfusion injury. : Pigs (18.2 ± 2.4 kg) were assigned to one control and eight treatment groups. Bilateral latissimus dorsi muscle flaps were raised after saline administration (control) and 0, 4, 8, 12, 24, 48, 72, and 96 hours after nicorandil administration. Subsequently, flaps were subjected to 4 hours of ischemia and 48 hours of reperfusion. Viability was assessed, and biochemical probes were used to study nicorandil-induced infarct protection. : Protection by nicorandil was biphasic. Infarction reduced from 40.2 ± 1.9 percent (control) to 27.3 ± 1.7 percent and 24.0 ± 2.3 percent (p < 0.05) 0 and 4 hours after nicorandil administration, respectively (early phase protection). No difference was seen between control and treatment groups between 8 and 12 hours after nicorandil administration compared with the control. Infarct protection increased again (p < 0.05) at 24 (22.4 ± 2.0 percent), 48 (25.1 ± 2.1 percent), and 72 hours (28.5 ± 2.1 percent) but not at 96 hours (43.9 ± 4.6 percent) compared with control (late phase protection). The sarcolemmal and mitochondrial channels played a central role in the trigger and mediator mechanisms, respectively. Late protection was associated with lower myeloperoxidase activity and mitochondrial calcium overload and higher adenosine triphosphate content (p < 0.05). : Nicorandil induced 48-hour uninterrupted muscle infarct protection, starting 24 hours after intravenous administration. This category of clinical drug is a potential prophylactic treatment against skeletal muscle ischemia-reperfusion injury in reconstructive surgery.
    No preview · Article · Mar 2013 · Plastic and Reconstructive Surgery
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    ABSTRACT: Deformational plagiocephaly (DP) is a multifactorial non-synostotic cranial deformity with a reported incidence as high as 1 in 7 infants in North America. Treatment options have focused on non-operative interventions including head repositioning and the use of an orthotic helmet device. Previous studies have used linear and two dimensional outcome measures to assess changes in cranial symmetry after helmet therapy. Our objective was to demonstrate improvement in head shape after treatment with a cranial molding helmet by using Root Mean Square (RMS), a measure unique to 3D photogrammetry, which takes into account both changes in volume and shape over time. Three dimensional photographs were obtained before and after molding helmet treatment in 40 infants (4–10 months old) with deformational plagiocephaly. Anatomical reference planes and measurements were recorded using the 3dMD Vultus® analysis software. RMS was used to quantify symmetry by superimposing left and right quadrants and calculating the mean value of aggregate distances between surfaces. Over 95% of the patients demonstrated an improvement in symmetry with helmet therapy. Furthermore, when the sample of infants was divided into two treatment subgroups, a statistically significant correlation was found between the age at the beginning of treatment and the change in the RMS value. When helmet therapy was started before 7 months of age a greater improvement in symmetry was seen. This work represents application of the technique of RMS analysis to demonstrate the efficacy of treatment of deformational plagiocephaly with a cranial molding helmet.
    No preview · Article · Jan 2013 · Journal of Plastic Reconstructive & Aesthetic Surgery

Publication Stats

3k Citations
259.82 Total Impact Points


  • 1988-2015
    • SickKids
      • Division of Plastic Surgery
      Toronto, Ontario, Canada
  • 1987-2014
    • University of Toronto
      • • Department of Surgery
      • • Hospital for Sick Children
      • • Sunnybrook Health Sciences Centre
      Toronto, Ontario, Canada
  • 2003
    • Semmelweis University
      Budapeŝto, Budapest, Hungary
  • 1991-1993
    • Sunnybrook Health Sciences Centre
      • Department of Plastic Surgery
      Toronto, Ontario, Canada