Effects of the subcranial approach on facial growth and development

Assessment of the Optic Foramen Shape and Size in Human Fetuses

OBJECTIVE

This study was aimed to obtain data on the dimensions of the optic foramen in human fetuses for early childhood surgeries.

METHODS

Twenty-five formalin-fixed fetuses (16 boys and 9 girls) with average age 21.68 ± 3.12 gestational weeks (range, 16-28 weeks) in the inventory of Anatomy Department, Faculty of Medicine were included in the study. The surface area, width, and height of the optic foramen were bilaterally measured using a digital image analysis software.

RESULTS

The forms of the optic foramen were described as oval shaped (72%, 36 foramina) and round shaped (28%, 14 foramina). The surface area, width, and height of the optic foramen were found as 2.40 ± 1.02 mm, 1.83 ± 0.59 mm, and 1.58 ± 0.36 mm, respectively. The measurements of the parameters related to the optic foramen were not statistically different in terms of sides and sexes (P > 0.05). Linear functions for the height, width and surface area of the optic foramen were calculated as: y = 0.711 + 0.040 × weeks, y = -0.019 + 0.086 × weeks, and y = -0.400 + 0.129 × weeks, respectively.

CONCLUSION

The linear functions in this study can be used to estimate the dimensions of the optic foramen. The calculated regression equations, representing the growth dynamic of the optic foramen showed that the surface area, width, and height were increasing according to gestational ages between 16 and 28 weeks. Microanatomical knowledge related to the optic foramen may be beneficial for surgeons to avoid iatrogenic injury in infants and for anatomists to understand the development of the fetal skull base.

Anatomic features of the cranial aperture of the optic canal in children: a radiologic study

OBJECTIVE

This study aimed to peruse anatomic features of the cranial aperture of the optic canal (CAOC) for obtaining an extended morphometric dataset in children.

METHODS

Computed tomography images of 200 children were included in this retrospective work to analyze the shape, location and diameters of the CAOC.

RESULTS

The CAOC area, width and height were observed as 17.53 ± 2.80 mm², 6.12 ± 0.84 mm, and 4.35 ± 0.64 mm, respectively. The angle of the optic canal in axial plane was found as 39.28 ± 5.13°, while in sagittal plane as 16.01 ± 6.76°. The distance between the CAOC and the midsagittal line was 7.17 ± 1.48 mm. The CAOC was measured as 54.04 ± 5.23 mm and 42.55 ± 3.28 mm away from the anterior and lateral boundary of the anterior skull base, respectively. The CAOC shape was described as the tear-drop (186 foramina, 46.5%), triangular (156 foramina, 39%), oval (47 foramina, 11.8%), and round (11 foramina, 2.8%).

CONCLUSION

The depth, angle and diameter measurements belonging to the CAOC were changing according to its shape or demographic data (e.g., sex and age). Therefore, preoperative radiologic evaluation containing the shape, location and size of the CAOC should be considered by multidisciplinary operating teams in terms of surgical interventions such as implant positioning.

A Computed Tomography Study of the Prechiasmatic Sulcus Anatomy in Children

PURPOSE

To investigate the characteristics of the prechiasmatic sulcus in children aged between 1-20 years.

METHODS

Patient files of 200 children admitted to the university hospital on 2019 were analyzed, retrospectively. The computed tomography images of patients were used to obtain anatomical knowledge containing prechiasmatic sulcus types and dimensions.

RESULTS

The measurements related to the sulcal length (6.94 ± 1.25 mm) and sulcal angle (31.01 ± 18.13°) showed that the sulcal length did not alter in children between 1 and 20 years, whereas the sulcal angle did not vary from infancy to prepubescent period, but it was decreasing in postpubescent period. In 29 patients, the sulcal length was observed to divide into 2 parts with an evident angle. The interoptic distance and planum length were found as follows: 14.70 ± 2.85 mm and 14.84 ± 4.12 mm, respectively. The order of PS types was observed as type 4 (26.5%, 53 cases) > type 2 (26%, 52 cases) > type 1 (24%, 48 cases) > type 3 (23.5%, 47 cases).

CONCLUSIONS

The sulcal length did not vary in children, whereas the sulcal angle decreased with an irregular pattern. The sulcal angle decreased after prepubescent period, possibly due to the sphenoid sinus pneumatization and spheno-occipital synchondrosis. The sulcal length angle mostly in infants and young children may cause surgical orientation difficult during the resection of tumors using transcranial approaches.

Radiologic analysis of the location, shape and size of the external aperture of the carotid canal in children

OBJECTIVES

This retrospective computed tomography (CT) study was aimed to assess the growth dynamic of the external aperture of the carotid canal (EACC) in children aged between 1 and 20 years.

METHODS

Two hundred patients (sex 100 females/100 males, average age 10.50 ± 5.77 years) with good head CT image quality were included in this study. CT images of the patients were used to obtain data related to the location, shape and dimension of EACC.

RESULTS

EACC shapes were identified as oval shaped, round shaped, and tear-drop shaped in 58.3% (233 sides), 24% (96 sides) and 17.8% (71 sides), respectively. EACC length, disEACC-MSP (distance between EACC and midsagittal plane), and EACC width did not change from the prepubescence period; while, the disEACC-SC (distance between EACC and supramastoid crest) seemed to reach adult size in the postpubescence period. Linear functions for EACC length and width were calculated as: y = 5.453 + 0.091 × years, and y = 5.398 + 0.059 × years, respectively.

CONCLUSION

The regression equations of the measured parameters representing the growth dynamic of EACC in children can be helpful to estimate its size, location and angulation, which suggest that the dimension and distances to certain anatomical landmarks seemed to reach adult size in different developmental periods. In this context, the findings of this study may seem to emphasize the importance of preoperative radiological evaluation on skull base, related to EACC, for multidisciplinary surgeon teams during childhood surgeries in terms of patients' positioning, and the selection of appropriate surgical approach.

[Variability and age-related features of the anatomy of the midline structures of the anterior skull base]

The article presents the literature data on the structural variability and age-related features of the midline anatomical structures of the anterior skull base (frontal sinus, ethmoid bone, anterior parasellar region, and medial orbital wall). This is the area of surgical interests of neurosurgeons and rhinosurgeons. The study objective is to analyze the literature data on the individual variability and age-related anatomy of these structures. The work is illustrated with original images from the authors' personal archive. The individual anatomical features of eloquent structures in the surgical area (structures within the surgical corridor, key anatomical landmarks, optic tract, internal carotid and ethmoidal arteries, etc.) should be considered in planning surgery in patients of all age groups because they can limit the view and the amount of safe manipulations or increase the risk of complications. The presented data may be useful for neurosurgeons and otolaryngologists whose surgical interests are focused on the midline structures of the anterior skull base.

Open Approaches to the Anterior Skull Base in Children: Review of the Literature

Introduction  Skull base lesions in children and adolescents are rare, and comprise only 5.6% of all skull base surgery. Anterior skull base lesions dominate, averaging slightly more than 50% of the cases. Until recently, surgery of the anterior skull base was dominated by open procedures and endoscopic skull base surgery was reserved for benign pathologies. Endoscopic skull base surgery is gradually gaining popularity. In spite of that, open skull base surgery is still considered the "gold standard" for the treatment of anterior skull base lesions, and it is the preferred approach in selected cases. Objective  This article reviews current concepts and open approaches to the anterior skull base in children in the era of endoscopic surgery. Materials and Methods  Comprehensive literature review. Results  Extensive intracranial-intradural invasion, extensive orbital invasion, encasement of the optic nerve or the internal carotid artery, lateral supraorbital dural involvement and involvement of the anterior table of the frontal sinus or lateral portion of the frontal sinus precludes endoscopic surgery, and mandates open skull base surgery. The open approaches which are used most frequently for surgical resection of anterior skull base tumors are the transfacial/transmaxillary, subcranial, and subfrontal approaches. Reconstruction of anterior skull base defects is discussed in a separate article in this supplement. Discussion  Although endoscopic skull base surgery in children is gaining popularity in developed countries, in many cases open surgery is still required. In addition, in developing countries, which accounts for more than 80% of the world's population, limited access to expensive equipment precludes the use of endoscopic surgery. Several open surgical approaches are still employed to resect anterior skull base lesions in the pediatric population. With this large armamentarium of surgical approaches, tailoring the most suitable approach to a specific lesion in regard to its nature, location, and extent is of utmost importance.

Skull Base Reconstruction in the Pediatric Patient

Introduction  Pediatric skull base and craniofacial reconstruction presents a unique challenge since the potential benefits of therapy must be balanced against the cumulative impact of multimodality treatment on craniofacial growth, donor-site morbidity, and the potential for serious psychosocial issues. Objectives  To suggest an algorithm for skull base reconstruction in children and adolescents after tumor resection. Materials and Methods  Comprehensive literature review and summary of our experience. Results  We advocate soft-tissue reconstruction as the primary technique, reserving bony flaps for definitive procedures in survivors who have reached skeletal maturity. Free soft-tissue transfer in microvascular technique is the mainstay for reconstruction of large, three-dimensional defects, involving more than one anatomic region of the skull base, as well as defects involving an irradiated field. However, to reduce total operative time, intraoperative blood loss, postoperative hospital stay, and donor-site morbidity, locoregional flaps are better be considered the flap of first choice for skull base reconstruction in children and adolescents, as long as the flap is large enough to cover the defect. Our "workhorse" for dural reconstruction is the double-layer fascia lata. Advances in endoscopic surgery, image guidance, alloplastic grafts, and biomaterials have increased the armamentarium for reconstruction of small and mid-sized defects. Conclusions  Skull base reconstruction using locoregional flaps or free flaps may be safely performed in pediatrics. Although the general principles of skull base reconstruction are applicable to nearly all patients, the unique demands of skull base surgery in pediatrics merit special attention. Multidisciplinary care in experienced centers is of utmost importance.

In defence of transpalatal, transpalatal-circumaxillary (transpterygopalatine) and transpalatal-circumaxillary-sublabial approaches to lateral extensions of juvenile nasopharyngeal angiofibroma

Background:

Juvenile nasopharyngeal angiofibroma often presents with lateral extensions. In countries with limited resources, selection of a cost-effective and least morbid surgical approach for complete excision is challenging.

Methods:

Sixty-three patients with juvenile nasopharyngeal angiofibroma, with lateral extensions, underwent transpalatal, transpalatal-circumaxillary (transpterygopalatine) or transpalatal-circumaxillary-sublabial approaches for resection. Clinico-radiological characteristics, tumour volume and intra-operative bleeding were recorded.

Results:

The transpalatal approach was suitable for extensions involving medial part of pterygopalatine fossa; transpalatal-circumaxillary for extensions involving complete pterygopalatine fossa, with or without partial infratemporal fossa; and transpalatal-circumaxillary-sublabial for extensions involving complete infratemporal fossa, even cheek or temporal fossa up to zygomatic arch. Haemorrhage was greatest with the transpalatal-circumaxillary-sublabial approach, followed by transpalatal approach and transpalatal-circumaxillary approach (1212, 950 and 777 ml respectively). Tumour size (volume) was greatest with the transpalatal-circumaxillary approach, followed by transpalatal-circumaxillary-sublabial approach and transpalatal approach (40, 34 and 29 mm3). There was recurrence in three cases and residual disease in two cases. Long-term morbidity included small palatal perforation (n = 1), trismus (n = 1) and atrophic rhinitis (n = 2).

Conclusion:

These modified techniques, performed with endoscopic assistance under hypotensive anaesthesia, without embolisation, offer a superior option over other open procedures with regard to morbidity and recurrences.

Subcranial approach in pediatric craniofacial surgery

We report our experience with the subcranial approach, developed at the Plastic Surgery Unit of Hospital "Ricardo Gutiérrez," for the treatment of injuries in the frontoethmoidal orbital region in pediatric patients. The subcranial approach was described by Raveh et al for the treatment of fractures in the frontoethmoidal area. The subcranial approach was used later for surgery of tumors and deformities of the frontoethmoidal region. We have used this approach in nine cases of nontraumatic injuries (one meningioma, one orbital bone fibrous dysplasia, one vascular malformation, five nasal dermoid cysts, and one fronto-orbital mucocele). One patient with vascular malformation died of a stroke 10 days after surgery. The patient with the meningioma had a recurrence. Another patient developed an infection that needed surgical resolution and hardware removal. A third patient suffered a mild infection that receded with medication. No other complications were registered. The surgical exposure obtained through this approach was always excellent and left no cosmetic defects. There was no evidence of facial growth disturbance in this group of patients, except in one patient who received radiotherapy after surgery. Operative time and hospitalization were lower in this group than in patients with conventional frontal craniotomy.

Surgical ablation and free flap reconstruction in children with malignant head and neck tumors

We assessed the feasibility and safety of free flap reconstruction in children undergoing extensive surgical excision of malignant head and neck tumors. We performed a retrospective review in a tertiary referral center of all patients aged 18 years or younger who underwent free flap reconstruction following resection of malignant head and neck tumors at our institution. Main outcome measures included complications at the primary and donor sites, functional and esthetic outcome, and tumor control. Eight of the 237 (3.4%) free flap reconstructions were performed on children. All tumors were malignant sarcomas. Ablative surgery was via a transfacial (n = 4) or a combined approach (n = 4). Transferred free flaps were the rectus abdominis (n = 3), gracilis (n = 3), fibula (n = 1), and anterolateral thigh (n = 1). The mean follow-up was 25.5 months. The overall early and late complication rates were 50% and 25%, respectively. There were no flap losses and no donor site complications. Functional outcome, including mastication, deglutition, and speech, was satisfactory. Local tumor control rate at last follow-up was 87.5%. Free flap reconstruction is an efficient and relatively safe technique for reconstructing surgical defects of the head and neck in children undergoing extensive surgery for malignant disease.

Surgical management of large juvenile nasopharyngeal angiofibroma invading the infratemporal fossa with intracranial extradural parasellar involvement in an 8-year-old boy

We present a rare case of a large juvenile nasopharyngeal angiofibroma (JNA) in an 8-year-old boy. Preoperative imaging revealed that the tumor had widely extended to the sphenoid sinus, infratemporal fossa, and cavernous sinus. Following embolization of the feeding vessels, the tumor was successfully removed by a combination of an orbitozygomatic approach and Le Fort I osteotomy under frontolateral craniotomy. An endoscope assisted in the surgery. At 15 months follow-up, the patient was free of the disease with no facial palsy, scars, or malocclusion. JNA is a benign tumor that typically affects adolescent males and is rarely observed during prepuberty. Complete removal of JNA by surgery, the initial therapy, is generally required. However, as in the present case, a large JNA with wide extension requires extended surgery, and such a surgery is more invasive for prepubertal patients. Using an appropriate combination of surgical approaches, a large JNA developed during prepuberty can be safely removed with reduced morbidity.

Surgical treatment of juvenile nasopharyngeal angiofibroma with intracranial extension. Clinical article

OBJECT

The purpose of this study was to describe the surgical treatment and outcomes of patients with intracranial extension of juvenile nasopharyngeal angiofibroma (JNA).

METHODS

Twenty-one patients who underwent operations for JNAs between 1994 and 2008 were enrolled in the study. Seven patients (33%) had intracranial tumor extension. The middle cranial fossa and cavernous sinus were involved in 4 patients who underwent operations via the combined infratemporal fossa-midfacial degloving approach. The anterior skull base was involved in 3 patients who underwent the subcranialmidfacial degloving approach.

RESULTS

Complete tumor removal was achieved in all patients. Postoperative complications included 1 case of soft-tissue infection. None of the patients had tumor recurrence after a mean follow-up of 42 months (range 29-85 months). No adjuvant therapy was required in any patient.

CONCLUSIONS

Combined approaches can be used effectively for treatment of JNAs with intracranial extension without the need for adjuvant therapy.

Multidisciplinary surgical approach for cerebrospinal fluid leak in children with complex head trauma

INTRODUCTION

Post-traumatic cerebrospinal fluid leak from the anterior cranial fossa in children may be isolated or combined with severe facial and calvarial injury. Untreated leak may result with meningitis, hydrocephalus, and abnormal neurocognitive development.

PATIENTS AND METHODS

We present nine children, ages 4-16 years, with complicated craniofacial injury treated by a combined subcranial and intracranial approach. A continuous lumbar drainage was kept for several days, and prophylactic antibiotics and anti-convulsive medications were routinely given. A multidisciplinary approach including discussion before surgery about other surgical options (endoscopic extracranial and intracranial alone) were performed.

RESULTS

None of the operated children had episodes of meningitis/leak after the combined approach, suggesting that appropriate sealing of the base of the skull has been achieved. There was no mortality, and the long-term follow-up showed good developmental and cosmetic results. Most of the children had significant brain contusions prior to surgery; however, these did not progress as minimal retraction was enabled by the extensive subcranial and intracranial approach.

CONCLUSIONS

Child's age, anatomy of the bone, extent of cranial injury, and clinical parameters should be seriously considered when choosing the technical methods as for sealing base of skull and reconstruction of facial/cranial bones. Young age does not seem to be a contraindication to the combined approach, thus, we recommend considering it in extensive base of skull fractures when concomitant cranial, maxillofacial, and orbital fractures coexist, as alternative options may not suffice in these cases.