Damian D. Marucci

Resistance forces acting on suture needles

Understanding the resistance forces encountered by a suture needle during tissue penetration is important for the development of robotic surgical devices and virtual reality surgical simulators. Tensile forces applied to skin and tendon during suturing were measured. Fresh sheep achilles tendons were tensioned with a static load 4.9 N, 9.8 N or 19.6 N and sheepskin with 0.98 N, 2.9 N or 4.9 N static load. A straight 2/0 cutting suture needle in series with a load cell on a materials testing machine penetrated the tissue at 90 degrees with a velocity of 1, 5 or 10mm/s for each tissue tension (n=5). Continuous load versus displacement data was obtained and penetration load and stiffness were noted. The load versus displacement curve for skin during needle penetration demonstrated two characteristic peaks, corresponding to initial penetration and emergence of needle from the undersurface of the tissue. Increasing the tension within the tissue (skin and tendon) increased the amount of force required to penetrate the tissue with a suture needle (p<0.05). Needle displacement rate did not affect the resistance to needle penetration (p<0.05). This study provides a simple model for measuring force-feedback during needle penetration of soft tissues and is a good starting point for future studies of the penetration resistance properties of human tissues.

Raised intracranial pressure in Apert syndrome.

Background: Raised intracranial pressure is a well-known complication of Apert syndrome. The current policy in the authors’ unit is to monitor these patients and only perform surgery when raised intracranial pressure has been diagnosed. The authors present their experience with this protocol, as it allows a more accurate picture of the natural history of raised intracranial pressure in Apert syndrome. Methods: The records of 24 patients, aged between 7 and 14 years, with Apert syndrome who had been managed expectantly (i.e., with no routine “automatic” early surgery) were reviewed. Data were collected on the incidence, timing, and management of raised intracranial pressure. Results: Twenty of 24 patients (83 percent) developed raised intracranial pressure. The average age of the first episode was 18 months (range, 1 month to 4 years 5 months). Raised intracranial pressure was managed with surgery in 18 patients, including two patients who underwent shunt procedures for hydrocephalus. Two patients had their raised intracranial pressure treated successfully by correcting coexisting upper airway obstruction alone. Seven of the 20 patients (35 percent) developed a second episode of raised intracranial pressure, on average 3 years 4 months later (range, 1 year 11 months to 5 years 9 months). Conclusions: In Apert syndrome, there is a high incidence of raised intracranial pressure, which can first occur at any age up to 5 years and may recur despite initial successful treatment. Causes of raised intracranial pressure include craniocerebral disproportion, venous hypertension, upper airway obstruction, and hydrocephalus. Careful clinical, ophthalmologic, respiratory, and radiologic monitoring will allow raised intracranial pressure to be diagnosed accurately when it occurs and then treated most appropriately.

Ocular advancement in monobloc distraction.

Background: Monobloc distraction has been demonstrated to be an efficacious, safe, and stable method of providing functional and aesthetic improvement in children with syndromic craniosynostosis. Although the movement of bony structures following monobloc distraction has been quantitatively assessed before, objective analysis of the movement of soft tissues, such as the globe, has not been published previously. The authors present a method that assesses globe movement following monobloc distraction, using computed tomographic scan data. Methods: The preoperative and postoperative computed tomographic scans of 10 patients with Pfeiffer’s and Crouzon’s syndromes, undergoing monobloc distraction, were assessed. Scan data were loaded into voxel image-rendering software that produced a three-dimensional reconstruction. Direct measurements between preoperative and postoperative images were taken. Results: An average upper face osseous distraction distance of 12.94 mm, with an average lower face distraction of 14.19 mm, was achieved in all 10 children. The authors measured average globe movements on three planes and calculated an average left eye forward movement of 5.28 mm and average right eye forward movement of 6.33 mm. In all, globe advancement was approximately two fifths of the distance advanced by the surrounding bone. Conclusions: Forward movement of the globe following monobloc distraction has not previously been described. Although there is no current evidence for optic nerve stretch and compromise in monobloc surgery, the functional implications of these findings should be formally assessed.

A compliant tip reduces the peak pressure of laparoscopic graspers

Background:  Previous studies have demonstrated that high pressures are generated at the tips of laparoscopic graspers, which can cause tissue injury. This study examines the effect of a compliant edge on tip pressure.

Development of a New Module of the FACE-Q for Children and Young Adults with Diverse Conditions Associated with Visible and/or Functional Facial Differences

Abstract Appearance and facial function are concepts not well addressed in current pediatric patient‐reported outcome measures (PROM) for facial conditions. We aimed to develop a new module of the FACE‐Q for children/young adults with facial conditions that include ear anomalies, facial paralysis, skeletal conditions, and soft tissue conditions. Semi‐structured and cognitive interviews were conducted with patients aged 8‐29 years recruited from craniofacial centers in Canada, USA, UK, and Australia. Interviews were used to elicit new concepts and to obtain feedback on CLEFT‐Q scales hypothesized to be relevant to other facial conditions. Interview data were recorded, transcribed, and coded. Experts were emailed and invited to provide feedback via Research Electronic Data Capture (REDCap). Eighty‐four participants and 43 experts contributed. Analysis led to the development of a conceptual framework and 14 new scales that measure appearance, facial function, health‐related quality of life, and adverse effects of treatment. In addition, 12 CLEFT‐Q scales were determined to have content validity for use with other facial conditions. Expert input led to minor changes to scales and items. This new FACE‐Q module for children/young adults is being field‐tested internationally. Once finalized, we anticipate this PROM will be used to inform clinical practice and research studies.

Frontoethmoidal mucocele following pediatric craniofacial surgery.

Background Mucoceles occur as a result of accumulation and retention of mucous secretions in a paranasal sinus and are uncommon in the pediatric age group. Persistent or intermittent closure of its ostium through a variety of causes, including previous surgery, is implicated in etiology. The authors report 2 cases of frontoethmoidal mucocele that followed box osteotomies for the treatment of orbital dystopia, with medical literature review and discussion of possible causal factors and events. Methods Case histories and radiological imaging are presented on 2 patients presenting with frontoethmoidal mucoceles following craniofacial surgery. Both had transcranial craniofacial techniques where all orbital walls and globe are moved en bloc as a “box.” Results Patient 1, a 12-year-old male patient with Crouzon syndrome, developed mucoceles within 18 months of monobloc distraction surgery and box osteotomies. This was successfully marsupialized with a combined external and endoscopic surgical approach. The second patient, a 15-year-old boy with previously corrected right-sided facial cleft, developed mucocele 9 years following box osteotomies; this was successfully managed by endoscopic drainage. Of 3 other patients having similar box osteotomies in our unit, no other mucoceles were noted as complications. Conclusions Mucoceles are a rare complication of craniofacial surgery, and literature review confirms a paucity of reports. Only 1 case has previously been alluded to of mucocele complicating box osteotomy for orbital dystopia. Our 2 cases illustrate and highlight a successful management approach in a multidisciplinary craniofacial unit.