Reconstruction of residual cleft nasal deformities in adolescents: Effects on social perceptions

PURPOSE

The investigators hypothesized that a layperson's social perceptions of a primarily repaired adolescent cleft lip and palate (CL/P) patient is more favorable after definitive nasal reconstruction with regard to perceived social traits.

METHODS

The investigators implemented a survey comparing layperson's social perceptions of 6 personality traits, 6 emotional expression traits, and 7 perceptions of interpersonal experiences before and >6 months after definitive nasal reconstruction in CL/P adolescent subjects by viewing standardized facial photographs. The sample was composed of consecutive CL/P subjects treated by one surgeon using a consistent technique involving a rib cartilage caudal strut graft through an open approach. Five non-cleft adolescent subjects who underwent cosmetic rhinoplasty involving a septal cartilage caudal strut graft through an open approach were used as a comparison group. The outcome variable was change in 6 perceived personality, 6 emotional expression traits studied, and 7 perceptions of interpersonal experiences. Descriptive and bivariate statistics were computed (p-value <0.05).

RESULTS

The sample was composed of 10 consecutive CL/P subjects and 5 non-cleft adolescent comparison subjects. 500 respondents (raters) completed the survey. The respondents were 54% male with 56% age 25 to 34. After definitive cleft nasal reconstruction, study subjects were perceived to be significantly more attractive (p = 0.04) and less threatening (p = 0.04). They were also perceived as less angry (p < 0.01), sad (p < 0.01), or disgusted (p < 0.01) than prior to surgery. The subjects were also perceived to be less likely to have negative interpersonal experiences (p < 0.01).

CONCLUSION

We confirmed that laypeople consistently report positive changes in adolescent CL/P subject's perceived social traits after definitive cleft nasal reconstruction. Overall, the positive changes were largely comparable between the cleft and non-cleft groups.

Pediatric Nasoorbitoethmoid Fractures: Cause, Classification, and Management

BACKGROUND

Currently, there is a paucity of information on the presentation and proper management of pediatric nasoorbitoethmoid fractures. The purpose of this study was to examine the incidence, cause, associated injuries, and management of these fractures. Furthermore, the authors sought to assess outcomes after transnasal wiring or suture canthopexy for type III nasoorbitoethmoid fractures.

METHODS

A retrospective cohort review was performed of all patients with nasoorbitoethmoid fractures who presented to a Level I trauma center from 1990 to 2010. Charts and computed tomographic imaging were reviewed, and nasoorbitoethmoid fractures were labeled based on the Markowitz-Manson classification system. Patient fracture patterns, demographics, characteristics, and outcomes were recorded. Univariate and multivariate methods were used to compare groups.

RESULTS

A total of 63 pediatric patients were identified in the study period. The sample's mean age was 8.78 ± 4.08 years, and 28.6 percent were girls. The sample included 18 type I injuries, 28 type II injuries, and 17 type III injuries. No significant demographic differences were found between patients with type I, II, and III fractures (p > 0.05). Operative intervention was pursued in 16.7, 46.4, and 82.4 percent of type I, II, and III nasoorbitoethmoid fractures, respectively. In patients with type III nasoorbitoethmoid fractures, no patients with transnasal wiring developed telecanthus.

CONCLUSIONS

Pediatric nasoorbitoethmoid fractures are uncommon injuries. Type I fracture can often be treated with close observation. However, type II and III injury patterns should be evaluated for operative intervention. Transnasal wiring is an effective method to prevent traumatic telecanthus deformity in type III fracture patterns.

Unusual Radiographic Presentation of Intracranial Mature Teratoma and Resection via Supraorbital Approach

BACKGROUND

Primary intracranial teratomas account for <1% of intracranial masses during childhood after infancy. When supratentorial, they commonly occur in the pineal and suprasellar regions, demonstrating multilocularity, areas of fat, and calcifications and increasing enhancement correlating with decreased maturity. However, the presence of a teratoma as a mobile fat lesion within a large unilocular suprasellar cyst is rarely documented in this patient population.

CASE DESCRIPTION

We present the first pediatric case of a suprasellar mature teratoma presenting as a mobile fat suppressing lesion within a large unilocular suprasellar cyst and describe a supraorbital approach with adjunctive use of the endoscope for resection. We also provide a literature review of other cases presenting with similar radiographic findings.

CONCLUSIONS

Mature teratomas may manifest atypically as unilocular cystic lesions with a central mobile fatty component and are treated by gross total surgical resection. The supraorbital approach with adjunctive use of an endoscope can provide adequate exposure for resection with optimal cosmetic outcome.

Does Fracture Pattern Influence Functional Outcomes in the Management of Bilateral Mandibular Condylar Injuries?

The purpose of this study was to compare the functional outcomes of different types of bilateral mandibular condylar fractures. This was a retrospective study of patients with bilateral mandibular condylar fractures at a level-1 trauma center over a 15-year period. The primary predictor variable was fracture pattern, classified as type I (bilateral condylar), type II (condylar-subcondylar), or type III (bilateral subcondylar). Secondary predictor variables were demographic, injury-related, and treatment factors. Bivariate associations between the predictors and complication rates were computed; a multiple logistic regression model was utilized to adjust for confounders and effect modifiers. Thirty-eight subjects with bilateral condylar injuries met the inclusion criteria. The sample's mean age was 37.6 + 18.2 years, and 16% were female. The most common mechanisms of injury were motor vehicle collisions (53%) and falls (29%). Seventy-four percent had associated noncondylar mandibular fractures, and 32% of cases had concomitant midface fractures. Fifty-three percent of cases were classified as type I, 21% as type II, and 26% as type III. Ten subjects (26%) were managed with open reduction and internal fixation. The average length of follow-up was 4.5 + 6.3 months. After adjusting for confounders and effect modifiers, the type of fracture was a significant predictor of functional complications with type II injuries having the highest likelihood of a poor functional outcome (odds ratio: 7.77, 95% confidence interval: 1.45-41.53, p  = 0.02). Asymmetric bilateral mandibular condylar fractures may be associated with an increased risk of poor functional outcomes.

Computed Tomographic Analysis of the Sagittal Orbit-globe Relationship

Identifying the normal relationship of the orbital rims to the globes is critical in planning surgical correction of craniofacial deformities affecting the orbit. This article illustrates a technical proof of principle and mathematical basis for a computed tomography-based measurement of the sagittal orbit-globe relationship. The technique does not require subject cooperation and is, therefore, optimal for pediatric craniofacial surgical treatment planning and outcome evaluation.

Subcranial and orthognathic surgery for obstructive sleep apnea in achondroplasia

PURPOSE

Obstructive sleep apnea (OSA) is a common problem in patients with achondroplasia. The purpose of this study was to assess changes in airway volumes following various degrees of facial skeletal advancement.

METHODS

This was a retrospective evaluation of patients with achondroplasia who underwent facial skeletal advancement for obstructive sleep apnea. Patients were treated with either an isolated Le Fort III distraction (LF3) or Le Fort II distraction with or without subsequent Le Fort I and bilateral sagittal split osteotomies (LF2 ± LF1/BSSO). Demographic, cephalometric, volumetric, and polysomnographic variables were recorded pre- and postoperatively.

RESULTS

Six patients with achondroplasia underwent midface advancement for treatment of OSA (2 LF2 + LF1/BSSO, 2 LF2, 2 LF3). Patients undergoing LF2 + LF1/BSSO had consistent volumetric improvements at the nasopharyngeal and oropharyngeal levels (Δ ≥ +347% and ≥+253%, respectively). Patients undergoing LF2 alone had consistent improvement in the nasopharyngeal airway alone (Δ ≥ +214%). Patients undergoing LF3 alone had consistent, but less dramatic, changes in nasopharyngeal volume (Δ ≥ +97.1%). All patients undergoing LF2 distraction (with or without LF1/BSSO) had a ≥50% reduction in the apnea-hypopnea index (AHI) postoperatively; there was no improvement in AHI with LF3 alone.

CONCLUSION

In patients with achondroplasia-associated OSA there are variable improvements in airway volume. This preliminary report suggests that LF2 distraction, with or without subsequent LF1/BSSO, may provide consistent reductions in AHI relative to LF3 distraction.

Is Formal Research Training Associated With Academic Success in Oral and Maxillofacial Surgery?

PURPOSE

Pursuing promotion in academic rank and seeking funded research opportunities are core elements of academic practice. Our purpose was to assess whether formal research training influences academic rank or National Institutes of Health (NIH) funding among full-time academic oral and maxillofacial surgeons (OMSs).

MATERIALS AND METHODS

We performed a cross-sectional study of full-time academic OMSs in the United States. The primary predictor variable was completion of formal research training, defined as a research fellowship or advanced non-clinical doctoral research degree (PhD, DMSc, DPH, DPhil, ScD). The outcomes measures were current academic rank and successful acquisition of NIH funding (yes vs no). Other study variables included MD degree, clinical fellowship training, years since training completion, and Hirsch index (H-index), a measure of academic productivity. We computed the descriptive, bivariate, and multiple regression models and set P ≤ .05 as significant.

RESULTS

A total of 299 full-time academic OMSs were included in the study sample. Of the 299 OMSs, 41 (13.7%) had had formal research training. Surgeons with formal research training had a greater mean interval since completion of training (P = 0.01) and had a greater mean H-index (P = 0.02). Formal research training was not associated with academic rank (P = .10) but was associated with an increased likelihood of receiving NIH funding (P < .001). In a multiple logistic regression model, after adjusting for years since completing training and H-index, formal research training was associated with an increased likelihood of obtaining NIH funding (odds ratio, 3.22; 95% confidence interval, 1.15 to 9.00; P = .03).

CONCLUSIONS

Among academic OMSs, those with formal research training had greater success with obtaining NIH funding. However, formal research training did not appear to influence an OMS's current academic rank.

Which Factors Affect Citation Rates in the Oral and Maxillofacial Surgery Literature?

PURPOSE

Citation rate is one of several tools to measure academic productivity. The purposes of this study were to estimate and identify factors associated with citation rates in the oral and maxillofacial surgery (OMS) literature.

MATERIALS AND METHODS

This was a retrospective longitudinal study of publications in the Journal of Oral and Maxillofacial Surgery (JOMS), International Journal of Oral and Maxillofacial Surgery (IJOMS), and Oral Surgery, Oral Medicine, Oral Pathology, and Oral Radiology (OOOO) from January through December 2012. The predictor variables were author- and article-specific factors. The outcome variable was the citation rate, defined as the total number of citations for each article over a 4-year period. Descriptive, bivariate, and multiple regression statistics were computed.

RESULTS

The authors identified 993 articles published during 2012. The mean number of citations at 4 years after publication was 5.6 ± 5.3 (median, 4). In bivariate analyses, several author- and article-specific factors were associated with citation rates. In a multiple regression model adjusting for potential confounders and effect modifiers, first author H-index, number of authors, journal, OMS focus area, and Oxford level of evidence were significantly associated with citation rate (P ≤ .002).

CONCLUSION

The authors identified 5 factors associated with citation rates in the OMS literature. These factors should be considered in context when evaluating citation-based metrics for OMS. Studies that focus on core OMS procedures (eg, dentoalveolar surgery, dental implant surgery), are published in specialty-specific journals (eg, JOMS or IJOMS), and have higher levels of evidence are more likely to be cited.

Acellular Dermal Matrix as an Adjunct Material in Cleft Le Fort I Osteotomies

PURPOSE

To evaluate the use of acellular dermal matrix in the management of nasal lining deficiency at the time of Le Fort I osteotomy.

METHODS

This was a retrospective cohort study of patients with residual/recurrent oronasal fistulae who underwent Le Fort I osteotomy. In instances where there was an inadequate volume of nasal mucosa for tension-free closure or for defects >1 cm in width, the acellular dermal matrix was used for augmentation. Demographic and cleft-related factors were recorded. Complications (recurrent fistula, infection, seroma, and wound dehiscence) were recorded.

RESULTS

Over the 3-year period, the authors used acellular dermal matrix to augment nasal lining in 8 subjects. The sample's mean age was 18.7 ± 3.1 years; 5 subjects were male. Six patients had bilateral cleft defects. The mean follow-up time was 20.2 ± 3.2 years. There were no episodes of infection, seroma, wound dehiscence, or recurrent fistula.

CONCLUSION

Acellular dermal matrix is a useful adjunct for managing nasal liningdeficiency at the time of Le Fort I osteotomy. There were no episodes of bone graft extrusion, infection, tooth loss, or bone graft loss. The Enemark scores improved significantly across both subsets (P <0.001). There was 1 recurrent fistula in the allograft bone alone group.Residual alveolar clefts and oronasal fistulae can be successfully managed at the time of Le Fort I osteotomy using allograft bone and acellular dermal matrix.

Does the H Index Correlate With Academic Rank Among Full-Time Academic Craniofacial Surgeons?

OBJECTIVE

To assess the relationship between the H index and the academic rank among full-time academic craniofacial surgeons.

DESIGN

This was a cross-sectional study of full-time academic craniofacial surgeons.

SETTING

Data were compiled and analyzed at the Department of Plastic and Reconstructive Surgery, Johns Hopkins Hospital.

RESULTS

The study sample included 127 full-time academic craniofacial surgeons. Overall, 89% were men, the mean number of years since completion of training was 16.2 ± 11.2 years. Most surgeons had a background in plastic and reconstructive surgery. Approximately 75% had completed formal fellowship training. The mean H index for the sample was 12.4 ± 9.9. The H index was strongly correlated with academic rank (r_s = 0.62, p < 0.001). In a multiple linear regression model, adjusting for multiple confounders/effect modifiers, including number of years since training and total number of publications, the H index was significantly associated with academic rank (coefficient = 0.33, p = 0.04).

CONCLUSIONS

Among full-time academic craniofacial surgeons, the H index is strongly correlated with the academic rank.

Does negative pressure wound therapy applied to closed incisions following ventral hernia repair prevent wound complications and hernia recurrence? A systematic review and meta-analysis

Background

Despite advances in surgical technique, ventral hernia repair (VHR) remains associated with significant postoperative wound complications.

Objective

A systematic review and meta-analysis was performed to identify whether the application of negative pressure wound therapy to closed incisions (iNPWT) following VHR reduces the risk of postoperative wound complications and hernia recurrence.

Methods

The PubMed/MEDLINE, EMBASE and SCOPUS databases were searched for studies published through October 2015. Publications that met the following criteria were included: adult patients undergoing VHR; comparison of iNPWT with conventional dressings; and documentation of wound complications and/or hernia recurrence. The methodological quality of included studies was independently assessed using the Methodological Index for Non-Randomized Studies guidelines. Outcomes assessed included surgical site infection (SSI), wound dehiscence, seroma, and hernia recurrence. Meta-analysis was performed to obtain pooled ORs.

Results

Five retrospective cohort studies including 477 patients undergoing VHR were included in the final analysis. The use of iNPWT decreased SSI (OR 0.33 [95% CI 0.20 to 0.55]; P<0.0001), wound dehiscence (OR 0.21 [95% CI 0.08 to 0.55]; P=0.001) and ventral hernia recurrence (OR 0.24 [95% CI 0.08 to 0.75]; P=0.01). There was no statistically significant difference in the incidence of seroma formation (OR 0.59 [95% CI 0.27 to 1.27]; P=0.18).

Conclusion

For patients undergoing VHR, current evidence suggests a decreased incidence in wound complications using incisional NPWT compared with conventional dressings.

Does negative pressure wound therapy applied to closed incisions following ventral hernia repair prevent wound complications and hernia recurrence? A systematic review and meta-analysis

BACKGROUND

Despite advances in surgical technique, ventral hernia repair (VHR) remains associated with significant postoperative wound complications.

OBJECTIVE

A systematic review and meta-analysis was performed to identify whether the application of negative pressure wound therapy to closed incisions (iNPWT) following VHR reduces the risk of postoperative wound complications and hernia recurrence.

METHODS

The PubMed/MEDLINE, EMBASE and SCOPUS databases were searched for studies published through October 2015. Publications that met the following criteria were included: adult patients undergoing VHR; comparison of iNPWT with conventional dressings; and documentation of wound complications and/or hernia recurrence. The methodological quality of included studies was independently assessed using the Methodological Index for Non-Randomized Studies guidelines. Outcomes assessed included surgical site infection (SSI), wound dehiscence, seroma, and hernia recurrence. Meta-analysis was performed to obtain pooled ORs.

RESULTS

Five retrospective cohort studies including 477 patients undergoing VHR were included in the final analysis. The use of iNPWT decreased SSI (OR 0.33 [95% CI 0.20 to 0.55]; P<0.0001), wound dehiscence (OR 0.21 [95% CI 0.08 to 0.55]; P=0.001) and ventral hernia recurrence (OR 0.24 [95% CI 0.08 to 0.75]; P=0.01). There was no statistically significant difference in the incidence of seroma formation (OR 0.59 [95% CI 0.27 to 1.27]; P=0.18).

CONCLUSION

For patients undergoing VHR, current evidence suggests a decreased incidence in wound complications using incisional NPWT compared with conventional dressings.

Does Formal Research Training Lead to Academic Success in Plastic Surgery? A Comprehensive Analysis of U.S. Academic Plastic Surgeons

INTRODUCTION

It is currently unknown whether formal research training has an influence on academic advancement in plastic surgery. The purpose of this study was to determine whether formal research training was associated with higher research productivity, academic rank, and procurement of extramural National Institutes of Health (NIH) funding in plastic surgery, comparing academic surgeons who completed said research training with those without.

METHODS

This was a cross-sectional study of full-time academic plastic surgeons in the United States. The main predictor variable was formal research training, defined as completion of a postdoctoral research fellowship or attainment of a Doctor of Philosophy (PhD). The primary outcome was scientific productivity measured by the Hirsh-index (h-index, the number of publications, h that have at least h citations each). The secondary outcomes were academic rank and NIH funding. Descriptive, bivariate, and multiple regression statistics were computed.

RESULTS

A total of 607 academic surgeons were identified from 94 Accreditation Council for Graduate Medical Education-accredited plastic surgery training programs. In all, 179 (29.5%) surgeons completed formal research training. The mean h-index was 11.7 ± 9.9. And, 58 (9.6%) surgeons successfully procured NIH funding. The distribution of academic rank was the following: endowed professor (5.4%), professor (23.9%), associate professor (23.4%), assistant professor (46.0%), and instructor (1.3%). In a multiple regression analysis, completion of formal research training was significantly predictive of a higher h-index and successful procurement of NIH funding.

CONCLUSION

Current evidence demonstrates that formal research training is associated with higher scientific productivity and increased likelihood of future NIH funding.

Is the Pyriform Ligament Important for Alar Width Maintenance After Le Fort I Osteotomy?

PURPOSE

To determine whether identification and incorporation of the pyriform ligament in the alar cinch results in decreased alar base widening compared with standard alar cinch techniques.

MATERIALS AND METHODS

This was a retrospective case series and the sample was composed of patients undergoing Le Fort I osteotomy. Intraoperatively, the pyriform ligament was identified and incorporated in the alar cinch suture. Greatest alar width (GAW) measured immediately after closure was compared with GAW measured at least 5 months postoperatively. The change in alar base width was compared with that reported in the literature using other alar cinch techniques. Two case examples are reported.

RESULTS

The sample was composed of 15 patients (mean age, 27.1 yr; 27% female). The mean postoperative change in GAW was 1.0 ± 0.6 mm (2.59 ± 1.59%). Postoperative change in alar base width reported in the literature ranged from 0.5 to 10.8%.

CONCLUSION

The pyriform ligament is easily identified during exposure of the maxilla and pyriform aperture and can be used to control widening of the alar base after Le Fort I osteotomy.

The Effect of Self-Citations on the Hirsch Index Among Full-Time Academic Hand Surgeons

OBJECTIVE

To assess the magnitude of self-citation among a cohort of academic hand surgeons and estimate the effect of self-citation on the Hirsch index (h-index).

DESIGN

Cross-sectional study.

SETTING

Johns Hopkins Hospital, Department of Plastic and Reconstructive Surgery, Division of Hand Surgery.

RESULTS

The study sample comprised 364 full-time academic hand surgeons. Study subjects had an average of 45 ± 73 publications. The mean total number of citations was 800 ± 1738, the median number of self-citations was 2.5 (interquartile range [IQR]: 0-14.8), and the average frequency of self-citation was 2.2% ± 3.7%. Older surgeons were slightly less likely to self-cite (coefficient = 0.07; p = 0.001). Furthermore, as the total number of publications increased, the frequency of self-citation increased (coefficient = 0.03; p < 0.001). The h-index increased because of self-citation in 57 surgeons (15.7%). After adjusting for American Society for Surgery of the Hand status and academic rank, increasing rates of self-citation were associated with an increase in the h-index. Surgeons with 7 or more self-citations were more likely to have their h-index influenced by self-citation.

CONCLUSIONS

The rate of self-citation among full-time academic hand surgeons affiliated with fellowship programs is fairly low. For most of the surgeons, self-citation did not affect the h-index.

Health-related quality of life in 794 patients with a peripheral facial palsy using the FaCE Scale: a retrospective cohort study

OBJECTIVES

To describe the health-related quality of life of patients visiting a tertiary referral centre for facial palsy, and to analyse factors associated with health-related quality of life, using the FaCE Scale instrument.

DESIGN

Retrospective cohort study.

SETTING

The Facial Nerve Center at the Massachusetts Eye and Ear Infirmary, a tertiary referral centre.

PARTICIPANTS

Patients with a peripheral facial palsy visiting the centre for an initial consultation between August 2007 and June 2012.

MAIN OUTCOME MEASURES

The total FaCE score and the FaCE social function subdomain. Multiple regression models were developed to identify factors associated with the total FaCE score and FaCE social function score.

RESULTS

A total of 794 patients with a mean age of 47.0 ± 16.0 years were analysed in this study, of which 59.9% were female. The mean House-Brackmann, Sunnybrook, total FaCE and FaCE social function scores were 3.6 ± 1.5, 48.2 ± 21.2, 47.3 ± 19.3 and 55.5 ± 19.2, respectively. Increasing age (r = -0.229, P < 0.001) was associated with a lower total FaCE score. Female gender (r = -4.422, P = 0.033) and increased duration of palsy (r = -0.018, P = 0.041) were associated with lower FaCE social function scores.

CONCLUSIONS

While counselling patients on what to expect during the recovery process after facial paralysis is an important part of any clinical visit, FaCE score correlations suggest that female patients with chronic facial palsy and increased age constitute a patient category that may require additional time and attention to prevent or mitigate psychosocial dysfunction.

Quantitative analysis of dual-purpose, patient-specific craniofacial implants for correction of temporal deformity

BACKGROUND

The development of computer-assisted design, virtual modeling, and computed tomography has allowed precise customization of implants for patients who undergo neurosurgical or craniofacial surgery procedures. However, such techniques and implant designs have not adequately addressed temporal asymmetry due to postoperative bone resorption, temporalis muscle malposition/foreshortening, and/or temporal fat pad atrophy.

OBJECTIVE

We hypothesized that an alteration in customized craniofacial implant (CCI) design with a strategic extension inferolaterally and excessive material bulking would provide simultaneous reconstruction of coexisting temporal skull defects and therefore reduce the effect of soft tissue deformities.

METHODS

A single-surgeon, single-institution retrospective cohort study was performed to include 10 consecutive subjects who underwent cranioplasty reconstruction with modified implants during a 3-year period. Implants were placed with the use of our previously described pericranial-onlay technique. With the use of a computed tomography-based, computer-assisted design/manufacturing methodology, novel dual-purpose implants were designed to prevent and/or correct persistent temporal hollowing. The efficacy of the new CCI shape and design for cranial restoration of temporal symmetry was analyzed in both 2 and 3 dimensions.

RESULTS

In 2-dimensional analyses, the modified implant provided enhanced lateral projection (21%; 1.06 cm(3)) in areas closest to the temporal arch. Three-dimensional volumetric analyses demonstrated that additional bulking totaled 24 ± 11 cm(3) (range, 9-43 cm), which essentially replaced 40 ± 13.7% (range, 26%-60%) of the absent temporal volume contributing to persistent temporal hollowing.

CONCLUSION

Computer-designed, dual-purpose CCIs can be safely created with unprecedented shape to prevent and/or eradicate postoperative temporal deformity.

Virtual Surgical Planning for Orbital Reconstruction

The advent of computer-assisted technology has revolutionized planning for complex craniofacial operations, including orbital reconstruction. Orbital reconstruction is ideally suited for virtual planning, as it allows the surgeon to assess the bony anatomy and critical neurovascular structures within the orbit, and plan osteotomies, fracture reductions, and orbital implant placement with efficiency and predictability. In this article, we review the use of virtual surgical planning for orbital decompression, posttraumatic midface reconstruction, reconstruction of a two-wall orbital defect, and reconstruction of a large orbital floor defect with a custom implant. The surgeon managing orbital pathology and posttraumatic orbital deformities can benefit immensely from utilizing virtual planning for various types of orbital pathology.