Aesth Plast Surg DOI 10.1007/s00266-014-0284-8
CASE REPORT
CRANIOFACIAL/MAXILLOFACIAL
An Aesthetic Approach to the Anterior Cranial Fossa: The Endoscopic Transadnexal Transorbital Roof Method Prajwal Rajappa • Joshua Krass • Shwetambara Parakh Henry M. Spinelli • Jeffrey P. Greenfield
•
Received: 1 July 2013 / Accepted: 23 January 2014 Ó Springer Science+Business Media New York and International Society of Aesthetic Plastic Surgery 2014
Abstract Background This case report describes a transadnexal transorbital roof approach to the anterior cranial fossa to treat an epidural abscess in a patient who had previously undergone extensive craniofacial reconstruction secondary to fibrous dysplasia. A standard frontal craniotomy or even a supraciliary craniotomy would have been burdensome due to the positioning of the porous polyethylene implant as well as extensive scar tissue and adhesions from prior surgical procedures. Methods We performed a retrospective review of the case of a 15-year-old male with an epidural abscess treated at a university hospital. Results The patient tolerated the procedure well with no postoperative complications. Surgical operative time was approximately 1.5 h with minimal blood loss and the patient was discharged on postoperative day 2. Six weeks after antibiotic therapy (intravenous ampicillin/sulbactam, 2,000 mg q.i.d. for 6 days total), an MRI showed complete
resolution of the epidural abscess. At that time the patient had no visual changes, extraocular muscle dysfunction, headaches, periorbital cellulitis, or further seizures and is on no antiepileptic therapy. Conclusion Minimally invasive approaches to treat complex problems in certain circumstances can yield excellent results and limit morbidity encountered by more extensive procedures. In the future, more formal studies with a larger subset of patients will help determine what role these approaches will ultimately have. Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
P. Rajappa (&) J. Krass H. M. Spinelli J. P. Greenfield Department of Neurological Surgery, Weill Medical College of Cornell University, New York, NY, USA e-mail: [email protected]
J. Krass Section of Neurosurgery, St. John Providence Hospital & Medical Centers, Michigan State University, Southfield, MI, USA
J. Krass e-mail: [email protected] H. M. Spinelli e-mail: [email protected] J. P. Greenfield e-mail: [email protected] P. Rajappa S. Parakh J. P. Greenfield 525 E. 68th Street, Box 99, New York, NY 10065, USA e-mail: [email protected]
Keywords Endoscopic Transadnexal Transorbital Epidural abscess Anterior skull base
J. Krass 308 S Edison Ave., Royal Oak, MI 48067, USA S. Parakh H. M. Spinelli Division of Plastic Surgery, Department of Surgery, Weill Medical College of Cornell University, New York, NY, USA H. M. Spinelli 875 5th Ave., New York, NY 10021, USA
123
Aesth Plast Surg
Introduction Treatment of fibrous dysplasia poses many challenges to craniofacial plastic surgeons and neurosurgeons alike. These challenges increase dramatically in the setting of multiple surgeries, placement of alloplastic materials, and associated complications such as abscess formation. Poor wound healing with avascular tissue, a lack of available periosteal material, scar tissue adhering to the underlying dura, and cerebrospinal fluid (CSF) leakage are a few of the difficulties encountered in these procedures. In light of the above, when we encountered a 15-yearold patient who had an epidural abscess and had undergone extensive reconstruction with the use of alloplastic material on multiple occasions, we found that there is a paucity of literature on the most appropriate treatment strategy. We postulated that a transadnexal transorbital roof approach would provide a direct route to the abscess, decrease the manipulation of previously implanted materials, and provide vascular tissue that had not been previously disrupted. The use of the endoscope for visualization and illumination would allow the smallest corridor through which treating the abscess could be performed. It was felt that a minimally invasive approach could afford the patient an excellent outcome and decrease approach-related morbidity while still obtaining an excellent aesthetic result.
Illustrative Case History At 4 months of age, our 15-year-old male patient, who was born in Chile, was noted to have a ‘‘growth’’ near the right orbit that was surgically resected at that time. Subsequently, abnormal growth of the craniofacial skeleton continued and was formally diagnosed as fibrous dysplasia after a biopsy procedure at the age of 2. Since that time the patient had undergone five craniofacial reconstructive procedures involving the cranium, orbit, and anterior cranial fossa. The patient had also undergone multiple ophthalmologic and neurological examinations and has been free from any optic neuropathy, extraocular muscle (EOM) limitations, fundus pathology, developmental delay, or other neurological findings. Most recently the patient underwent surgical resection involving the bilateral frontal bones, bilateral orbits, and anterior cranial fossa. This consisted of a coronal incision in which significant scarring, fibrosis, and adhesions to the skull and dura from previously implanted methylmethacrylate cranioplasty were present upon exposure. This was followed by a bifrontal craniotomy and bilateral orbital osteotomy to access the mass and allow for complete en
123
Fig. 1 a Skull model with Medpor cranioplasty. b Superior orbital roof with planned craniectomy. c Transadnexal approach. d Postoperative wound
bloc resection. The procedure also included creation of a galeal frontalis myofascial flap to separate the nasal sinus cavity from the intracranial space, placement of a prefabricated customized porous polyethylene (MEDPORÒ, Stryker, Kalamazoo, MI) implant, and a cranioplasty using a combination of MEDPOR and wire mesh for the posterior cranial defect (Fig. 1a). During the craniotomy portion of the procedure, it was noted that the fibrous dysplasia had eroded through the dura and it was evident that there were several areas of exposed frontal lobe. This was covered with a deep temporalis fascia graft that was harvested from the right temporalis muscle and sutured in place, and with DuraGen (Integra LifeSciences, Plainsboro, NJ) and fibrin sealant at the sites of exposed brain at the completion of the procedure. The wound was closed in multiple layers at this time but was noted to be under tension secondary to the multiple surgeries and thinning in several areas. Following the procedure the patient did well for 7 weeks without complications but then he returned to us with dehiscence of the wound. It was noted at this time that there was full-thickness loss of tissue which exposed the underlying hardware and prosthetic skull with resultant contamination. It was determined that it would be necessary to return to the operating room for repair at that time and he underwent another coronal incision with galeal advancement and removal of the contaminated hardware without removal of the polyethylene implant. Eighteen months later the patient returned with headache, periorbital cellulitis, and new onset seizures for which he was admitted to the pediatric service for evaluation. The patient
Aesth Plast Surg Fig. 2 a Purulent exudate protruding through craniectomy site. b Intracranial view following evacuation, showing evacuation and a smooth inner surface of the abscess rind
was started on broad-spectrum antibiotic therapy as well. The patient underwent a computed tomography (CT) scan followed by a magnetic resonance imaging (MRI) scan with contrast. The MRI demonstrated a loculated epidural abscess on the right side of the anterior cranial fossa just superior to the right orbital roof. Based on these findings the neurosurgery service was consulted for evacuation/ decompression. Because of the previous multiple complicated surgeries, the plastic surgery and pediatric neurosurgery services determined that a standard craniotomy would be of significant risk and a minimally invasive transorbital approach with endoscopic assistance would afford the patient the best chance of having limited morbidity while still adequately treating the specified problem. Operative Procedure A transorbital approach was proposed with the guidance of Brainlab (Brainlab Inc., Westchester, IL) neuronavigation. After placing the patient in three-point head fixation to secure the head, the patient was positioned in the midline with slight extension to allow access to the orbital floor through as direct an approach as possible. Of importance was the placement of a lens coated with triple-antibiotic ointment over the cornea to prevent drying of the eye or inadvertent injury throughout the procedure. At this point an incision was outlined within the superior eyelid crease along the superior palpebral sulcus and a skin-muscle flap was elevated just deep to the orbicularis oculi muscle (Fig. 1c). Particular attention was paid to dissecting in a preseptal plane, with the posterior landmark being the identification of the orbicularis muscle, to avoid dissection into the levator aponeurosis, possibly leading to ptosis of the upper eyelid, as well as disruption and extrusion of the periorbital and potential damage to the lacrimal gland in the lateral extent of the dissection. A subperiosteal dissection was then carried out to expose the entire superior orbital roof. CT-based navigation was then used to identify the appropriate trajectory and site for drilling to ensue (Fig. 1b). A 1-cm craniectomy was fashioned through the previously placed porous polyethylene implant; copious
amounts of irrigation were used throughout the drilling to ensure no alloplastic material was left in the operative field. Upon drilling through the inner table, which was a combination of bone and MEDPOR, a large amount of purulent exudate extruded through the craniectomy site (Fig. 2a). This was irrigated until no exudate remained. Endoscopic visualization with a 0° 4.0-mm straight rigid endoscope (Karl Storz, Tuttlingen, Germany) was used throughout the procedure, and upon final inspection of the intracranial cavity there was complete resolution of the epidural abscess (Fig. 2b). There was no attempt at this point to resect the granulation tissue or abscess capsule; it was felt that the potential for CSF leak was increased secondary to multiple previous surgeries and it was unnecessary to cure the infection. The wound was then closed in a layered fashion using both absorbable and nonabsorbable sutures.
Results The patient tolerated the procedure well without complications. The operative time was approximately 1.5 h with minimal blood loss and the patient was discharged on postoperative day 2. Immediate postoperative MRI showed residual peripheral enhancement, which was anticipated secondary to not removing the abscess capsule because of the fear of causing increased morbidity with the possibility of CSF leak and because of the slight overall decrease in the size of the abscess in all dimensions (Fig. 3a, c). On the most recent follow-up, 6 weeks after surgery, the patient was doing well without any postoperative visual impairment, EOM dysfunction, diplopia, headaches, periorbital cellulitis, or further seizures and is not on any antiepileptic medications. The MRI at 6 weeks demonstrated complete resolution of the enhancing capsule and collapse of the cavity (Fig. 3b, d). The wound has also healed well without complications (Fig. 1d). The final pathologic diagnosis showed a gram stain that was positive for gram-negative rods but without growth on culture medium and for which the patient has been continued on broad-spectrum antibiotic therapy.
123
Aesth Plast Surg Fig. 3 Fat-sat contrastenhanced MRI of the orbit. a Preoperative coronal MRI. b Postoperative coronal MRI. c Preoperative axial MRI. d Postoperative coronal MRI
Discussion Approaches to anterior skull base pathology have evolved over the years as a result of advances in neuroimaging, anesthetic techniques, microneurosurgery equipment, and a multitude of studies outlining different approaches for a vast array of pathologic conditions found in this region. However, the ‘‘workhorse’’ approach for accessing the anterior cranial fossa has been a coronal incision followed by bi- or unifrontal craniotomy with or without orbital extensions. The overall familiarity of this approach and its proven long-term viability for a vast array of pathologies make it an attractive option for most surgeons. Coupled with the fact that this approach offers multiple options for the repair of CSF leaks and segregation of the intracranial contents from the paranasal sinuses, excellent visualization of neurovascular structures, and limited brain retraction
123
when done properly, it remains the standard approach to many pathologies of the anterior cranial fossa [1]. Despite these advantages, there are instances in which a limited incision and craniotomy can be extremely useful to limit the inherent morbidity associated with this approach [2]. This is especially true in the realm of craniofacial surgery where reoperation is necessary and the benefits of this approach are no longer viable in the decision-making process. Extensive scar tissue, decreased vascularity of the scalp, and a lack of pericranium are a few things to consider when determining the approach in these challenging cases. In this regard the use of neuroendoscopy to access the anterior cranial base is gaining increased acceptance worldwide. While most reports have been on the use of neuroendoscopy through a transnasal route, there have been several reports of using this technique at a wider array
Aesth Plast Surg
of locations, namely, a supraorbital approach and, less frequently, a transorbital approach [3–5]. Pathology encountered in this region can include masses adjacent to the orbit, including intracranial lesions, complex CSF leakage, orbital decompression, infection, epistaxis, and aneurysm clipping. However, this is an evolving process as surgeons are becoming more comfortable with the technical demands of neuroendoscopy and there is increased familiarity and availability of the necessary equipment to make full use of this advanced technology. The option of performing limited craniotomies, smaller incisions, decreased blood loss, and decreased hospital stay in some instances make this technology increasingly more attractive [6]. Despite the advantages, there are limitations to the use of neuroendoscopy that deserve attention. There is a steep learning curve that must be overcome to familiarize oneself with the benefits and limitations of the endoscopic approach. The increased availability of cadaver courses and instructional labs can help. In addition, using a tiered approach, starting with simpler cases and progressing to more advanced cases, can decrease operative time and patient morbidity. Instances in which bimanual manipulation or significant dissection are required may be limiting factors in using this approach. When highly vascular lesions are likely to be encountered, it is wise to take this into consideration as controlling significant bleeding through a purely endoscopic or even endoscopy-assisted procedure can prove challenging. Lastly, options for repair of CSF leaks are numerous, especially through a transnasal approach, however, research is extremely limited in regard to repair of these defects through other endoscopic approaches and can lead to significant morbidity if not planned for appropriately prior to the procedure. In the case presented here, it was felt that the orbit provided the most direct route to the epidural abscess while bypassing the approach-related morbidity of a standard craniotomy. Several factors were considered prior to choosing this approach, namely, potential risk to intraorbital structures, cosmesis, and an inability to completely eradicate the infection in the case of alloplastic material in the setting of infection. Despite these risks it was felt that in the context of the patient having previously undergone five surgeries through a single incision with significant scar tissue, decreased vascularity of the scalp, no pericranium present for reconstruction, and extensive anterior cranial fossa, orbital, and frontal bone reconstruction with alloplastic material, this would be a reasonable approach, with limited risk, to eradicate the abscess. In addition, the orbital roof of the implant was far thinner than the frontal bone, there was no need for brain retraction, and it afforded a very low risk of CSF leak.
Conclusion Indications for the use of neuroendoscopy continue to evolve. This report of a transadnexal transorbital approach to the anterior cranial fossa demonstrates limited theoretical morbidity while still allowing adequate access, visualization, and resolution of an epidural abscess, which would traditionally require a large craniotomy and all of the approach-related morbidity that is associated with it. We recognize that complex lesions requiring microsurgical or bimanual manipulation may need larger craniectomies or craniotomies, so-called keyhole access, but this points to the ability of endoscopic surgeons to tailor their skull base openings to the pathologic entities being approached. The transadnexal transorbital approach is especially rewarding in the described situation because of the extensive craniofacial reconstruction that the patient had previously undergone and the potential for serious complications following a more extensive procedure. Because of these benefits, we feel that increasing the scope of neuroendoscopic techniques, whether purely endoscopic or endoscopy-assisted, affords the surgeon in select cases the ability to reduce the morbidity typically associated with more standard procedures. Future research, whether case series or other reports describing both successful and unsuccessful use of endoscopic and other minimally invasive approaches to treat complex problems, will help to broaden the scope of acceptable alternative methods of treating similar problems. Conflict of interest The authors have no personal, financial, or institutional interest in any of the materials or devices described in this article.
References 1. Zimmer LA, Theodosopoulos PV (2009) Anterior skull base surgery: open versus endoscopic. Curr Opin Otolaryngol Head Neck Surg 17(2):75–78 2. Moe KS, Bergeron CM, Ellenbogen RG (2010) Transorbital neuroendoscopic surgery. Neurosurgery 67(3 Suppl Operative): ons16–28 3. Ciporen JN, Moes KS, Ramanathan D et al (2010) Multiportal endoscopic approaches to the central skull base: a cadaveric study. World Neurosurg 73(6):705–712 4. Beretta F, Andaluz N, Chalaala C et al (2010) Image-guided anatomical and morphometric study of supraorbital and transorbital minicraniotomies to the sellar and perisellar regions: comparison with standard techniques. J Neurosurg 113(5):975–981 5. Noggle JC, Scubba DM, Nelson C et al (2008) Supracilliary keyhole craniotomy for brain abscess debridement. Neurosurg Focus 24(6):E11 6. Abdel Aziz KM, Bhatia S, Tantawy MH et al (2011) Minimally invasive transpalpebral ‘‘eyelid’’ approach to the anterior cranial base. Neurosurgery 69(2 Suppl Operative):ons195–206 discussion 206-207
123
CASE REPORT
CRANIOFACIAL/MAXILLOFACIAL
An Aesthetic Approach to the Anterior Cranial Fossa: The Endoscopic Transadnexal Transorbital Roof Method Prajwal Rajappa • Joshua Krass • Shwetambara Parakh Henry M. Spinelli • Jeffrey P. Greenfield
•
Received: 1 July 2013 / Accepted: 23 January 2014 Ó Springer Science+Business Media New York and International Society of Aesthetic Plastic Surgery 2014
Abstract Background This case report describes a transadnexal transorbital roof approach to the anterior cranial fossa to treat an epidural abscess in a patient who had previously undergone extensive craniofacial reconstruction secondary to fibrous dysplasia. A standard frontal craniotomy or even a supraciliary craniotomy would have been burdensome due to the positioning of the porous polyethylene implant as well as extensive scar tissue and adhesions from prior surgical procedures. Methods We performed a retrospective review of the case of a 15-year-old male with an epidural abscess treated at a university hospital. Results The patient tolerated the procedure well with no postoperative complications. Surgical operative time was approximately 1.5 h with minimal blood loss and the patient was discharged on postoperative day 2. Six weeks after antibiotic therapy (intravenous ampicillin/sulbactam, 2,000 mg q.i.d. for 6 days total), an MRI showed complete
resolution of the epidural abscess. At that time the patient had no visual changes, extraocular muscle dysfunction, headaches, periorbital cellulitis, or further seizures and is on no antiepileptic therapy. Conclusion Minimally invasive approaches to treat complex problems in certain circumstances can yield excellent results and limit morbidity encountered by more extensive procedures. In the future, more formal studies with a larger subset of patients will help determine what role these approaches will ultimately have. Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
P. Rajappa (&) J. Krass H. M. Spinelli J. P. Greenfield Department of Neurological Surgery, Weill Medical College of Cornell University, New York, NY, USA e-mail: [email protected]
J. Krass Section of Neurosurgery, St. John Providence Hospital & Medical Centers, Michigan State University, Southfield, MI, USA
J. Krass e-mail: [email protected] H. M. Spinelli e-mail: [email protected] J. P. Greenfield e-mail: [email protected] P. Rajappa S. Parakh J. P. Greenfield 525 E. 68th Street, Box 99, New York, NY 10065, USA e-mail: [email protected]
Keywords Endoscopic Transadnexal Transorbital Epidural abscess Anterior skull base
J. Krass 308 S Edison Ave., Royal Oak, MI 48067, USA S. Parakh H. M. Spinelli Division of Plastic Surgery, Department of Surgery, Weill Medical College of Cornell University, New York, NY, USA H. M. Spinelli 875 5th Ave., New York, NY 10021, USA
123
Aesth Plast Surg
Introduction Treatment of fibrous dysplasia poses many challenges to craniofacial plastic surgeons and neurosurgeons alike. These challenges increase dramatically in the setting of multiple surgeries, placement of alloplastic materials, and associated complications such as abscess formation. Poor wound healing with avascular tissue, a lack of available periosteal material, scar tissue adhering to the underlying dura, and cerebrospinal fluid (CSF) leakage are a few of the difficulties encountered in these procedures. In light of the above, when we encountered a 15-yearold patient who had an epidural abscess and had undergone extensive reconstruction with the use of alloplastic material on multiple occasions, we found that there is a paucity of literature on the most appropriate treatment strategy. We postulated that a transadnexal transorbital roof approach would provide a direct route to the abscess, decrease the manipulation of previously implanted materials, and provide vascular tissue that had not been previously disrupted. The use of the endoscope for visualization and illumination would allow the smallest corridor through which treating the abscess could be performed. It was felt that a minimally invasive approach could afford the patient an excellent outcome and decrease approach-related morbidity while still obtaining an excellent aesthetic result.
Illustrative Case History At 4 months of age, our 15-year-old male patient, who was born in Chile, was noted to have a ‘‘growth’’ near the right orbit that was surgically resected at that time. Subsequently, abnormal growth of the craniofacial skeleton continued and was formally diagnosed as fibrous dysplasia after a biopsy procedure at the age of 2. Since that time the patient had undergone five craniofacial reconstructive procedures involving the cranium, orbit, and anterior cranial fossa. The patient had also undergone multiple ophthalmologic and neurological examinations and has been free from any optic neuropathy, extraocular muscle (EOM) limitations, fundus pathology, developmental delay, or other neurological findings. Most recently the patient underwent surgical resection involving the bilateral frontal bones, bilateral orbits, and anterior cranial fossa. This consisted of a coronal incision in which significant scarring, fibrosis, and adhesions to the skull and dura from previously implanted methylmethacrylate cranioplasty were present upon exposure. This was followed by a bifrontal craniotomy and bilateral orbital osteotomy to access the mass and allow for complete en
123
Fig. 1 a Skull model with Medpor cranioplasty. b Superior orbital roof with planned craniectomy. c Transadnexal approach. d Postoperative wound
bloc resection. The procedure also included creation of a galeal frontalis myofascial flap to separate the nasal sinus cavity from the intracranial space, placement of a prefabricated customized porous polyethylene (MEDPORÒ, Stryker, Kalamazoo, MI) implant, and a cranioplasty using a combination of MEDPOR and wire mesh for the posterior cranial defect (Fig. 1a). During the craniotomy portion of the procedure, it was noted that the fibrous dysplasia had eroded through the dura and it was evident that there were several areas of exposed frontal lobe. This was covered with a deep temporalis fascia graft that was harvested from the right temporalis muscle and sutured in place, and with DuraGen (Integra LifeSciences, Plainsboro, NJ) and fibrin sealant at the sites of exposed brain at the completion of the procedure. The wound was closed in multiple layers at this time but was noted to be under tension secondary to the multiple surgeries and thinning in several areas. Following the procedure the patient did well for 7 weeks without complications but then he returned to us with dehiscence of the wound. It was noted at this time that there was full-thickness loss of tissue which exposed the underlying hardware and prosthetic skull with resultant contamination. It was determined that it would be necessary to return to the operating room for repair at that time and he underwent another coronal incision with galeal advancement and removal of the contaminated hardware without removal of the polyethylene implant. Eighteen months later the patient returned with headache, periorbital cellulitis, and new onset seizures for which he was admitted to the pediatric service for evaluation. The patient
Aesth Plast Surg Fig. 2 a Purulent exudate protruding through craniectomy site. b Intracranial view following evacuation, showing evacuation and a smooth inner surface of the abscess rind
was started on broad-spectrum antibiotic therapy as well. The patient underwent a computed tomography (CT) scan followed by a magnetic resonance imaging (MRI) scan with contrast. The MRI demonstrated a loculated epidural abscess on the right side of the anterior cranial fossa just superior to the right orbital roof. Based on these findings the neurosurgery service was consulted for evacuation/ decompression. Because of the previous multiple complicated surgeries, the plastic surgery and pediatric neurosurgery services determined that a standard craniotomy would be of significant risk and a minimally invasive transorbital approach with endoscopic assistance would afford the patient the best chance of having limited morbidity while still adequately treating the specified problem. Operative Procedure A transorbital approach was proposed with the guidance of Brainlab (Brainlab Inc., Westchester, IL) neuronavigation. After placing the patient in three-point head fixation to secure the head, the patient was positioned in the midline with slight extension to allow access to the orbital floor through as direct an approach as possible. Of importance was the placement of a lens coated with triple-antibiotic ointment over the cornea to prevent drying of the eye or inadvertent injury throughout the procedure. At this point an incision was outlined within the superior eyelid crease along the superior palpebral sulcus and a skin-muscle flap was elevated just deep to the orbicularis oculi muscle (Fig. 1c). Particular attention was paid to dissecting in a preseptal plane, with the posterior landmark being the identification of the orbicularis muscle, to avoid dissection into the levator aponeurosis, possibly leading to ptosis of the upper eyelid, as well as disruption and extrusion of the periorbital and potential damage to the lacrimal gland in the lateral extent of the dissection. A subperiosteal dissection was then carried out to expose the entire superior orbital roof. CT-based navigation was then used to identify the appropriate trajectory and site for drilling to ensue (Fig. 1b). A 1-cm craniectomy was fashioned through the previously placed porous polyethylene implant; copious
amounts of irrigation were used throughout the drilling to ensure no alloplastic material was left in the operative field. Upon drilling through the inner table, which was a combination of bone and MEDPOR, a large amount of purulent exudate extruded through the craniectomy site (Fig. 2a). This was irrigated until no exudate remained. Endoscopic visualization with a 0° 4.0-mm straight rigid endoscope (Karl Storz, Tuttlingen, Germany) was used throughout the procedure, and upon final inspection of the intracranial cavity there was complete resolution of the epidural abscess (Fig. 2b). There was no attempt at this point to resect the granulation tissue or abscess capsule; it was felt that the potential for CSF leak was increased secondary to multiple previous surgeries and it was unnecessary to cure the infection. The wound was then closed in a layered fashion using both absorbable and nonabsorbable sutures.
Results The patient tolerated the procedure well without complications. The operative time was approximately 1.5 h with minimal blood loss and the patient was discharged on postoperative day 2. Immediate postoperative MRI showed residual peripheral enhancement, which was anticipated secondary to not removing the abscess capsule because of the fear of causing increased morbidity with the possibility of CSF leak and because of the slight overall decrease in the size of the abscess in all dimensions (Fig. 3a, c). On the most recent follow-up, 6 weeks after surgery, the patient was doing well without any postoperative visual impairment, EOM dysfunction, diplopia, headaches, periorbital cellulitis, or further seizures and is not on any antiepileptic medications. The MRI at 6 weeks demonstrated complete resolution of the enhancing capsule and collapse of the cavity (Fig. 3b, d). The wound has also healed well without complications (Fig. 1d). The final pathologic diagnosis showed a gram stain that was positive for gram-negative rods but without growth on culture medium and for which the patient has been continued on broad-spectrum antibiotic therapy.
123
Aesth Plast Surg Fig. 3 Fat-sat contrastenhanced MRI of the orbit. a Preoperative coronal MRI. b Postoperative coronal MRI. c Preoperative axial MRI. d Postoperative coronal MRI
Discussion Approaches to anterior skull base pathology have evolved over the years as a result of advances in neuroimaging, anesthetic techniques, microneurosurgery equipment, and a multitude of studies outlining different approaches for a vast array of pathologic conditions found in this region. However, the ‘‘workhorse’’ approach for accessing the anterior cranial fossa has been a coronal incision followed by bi- or unifrontal craniotomy with or without orbital extensions. The overall familiarity of this approach and its proven long-term viability for a vast array of pathologies make it an attractive option for most surgeons. Coupled with the fact that this approach offers multiple options for the repair of CSF leaks and segregation of the intracranial contents from the paranasal sinuses, excellent visualization of neurovascular structures, and limited brain retraction
123
when done properly, it remains the standard approach to many pathologies of the anterior cranial fossa [1]. Despite these advantages, there are instances in which a limited incision and craniotomy can be extremely useful to limit the inherent morbidity associated with this approach [2]. This is especially true in the realm of craniofacial surgery where reoperation is necessary and the benefits of this approach are no longer viable in the decision-making process. Extensive scar tissue, decreased vascularity of the scalp, and a lack of pericranium are a few things to consider when determining the approach in these challenging cases. In this regard the use of neuroendoscopy to access the anterior cranial base is gaining increased acceptance worldwide. While most reports have been on the use of neuroendoscopy through a transnasal route, there have been several reports of using this technique at a wider array
Aesth Plast Surg
of locations, namely, a supraorbital approach and, less frequently, a transorbital approach [3–5]. Pathology encountered in this region can include masses adjacent to the orbit, including intracranial lesions, complex CSF leakage, orbital decompression, infection, epistaxis, and aneurysm clipping. However, this is an evolving process as surgeons are becoming more comfortable with the technical demands of neuroendoscopy and there is increased familiarity and availability of the necessary equipment to make full use of this advanced technology. The option of performing limited craniotomies, smaller incisions, decreased blood loss, and decreased hospital stay in some instances make this technology increasingly more attractive [6]. Despite the advantages, there are limitations to the use of neuroendoscopy that deserve attention. There is a steep learning curve that must be overcome to familiarize oneself with the benefits and limitations of the endoscopic approach. The increased availability of cadaver courses and instructional labs can help. In addition, using a tiered approach, starting with simpler cases and progressing to more advanced cases, can decrease operative time and patient morbidity. Instances in which bimanual manipulation or significant dissection are required may be limiting factors in using this approach. When highly vascular lesions are likely to be encountered, it is wise to take this into consideration as controlling significant bleeding through a purely endoscopic or even endoscopy-assisted procedure can prove challenging. Lastly, options for repair of CSF leaks are numerous, especially through a transnasal approach, however, research is extremely limited in regard to repair of these defects through other endoscopic approaches and can lead to significant morbidity if not planned for appropriately prior to the procedure. In the case presented here, it was felt that the orbit provided the most direct route to the epidural abscess while bypassing the approach-related morbidity of a standard craniotomy. Several factors were considered prior to choosing this approach, namely, potential risk to intraorbital structures, cosmesis, and an inability to completely eradicate the infection in the case of alloplastic material in the setting of infection. Despite these risks it was felt that in the context of the patient having previously undergone five surgeries through a single incision with significant scar tissue, decreased vascularity of the scalp, no pericranium present for reconstruction, and extensive anterior cranial fossa, orbital, and frontal bone reconstruction with alloplastic material, this would be a reasonable approach, with limited risk, to eradicate the abscess. In addition, the orbital roof of the implant was far thinner than the frontal bone, there was no need for brain retraction, and it afforded a very low risk of CSF leak.
Conclusion Indications for the use of neuroendoscopy continue to evolve. This report of a transadnexal transorbital approach to the anterior cranial fossa demonstrates limited theoretical morbidity while still allowing adequate access, visualization, and resolution of an epidural abscess, which would traditionally require a large craniotomy and all of the approach-related morbidity that is associated with it. We recognize that complex lesions requiring microsurgical or bimanual manipulation may need larger craniectomies or craniotomies, so-called keyhole access, but this points to the ability of endoscopic surgeons to tailor their skull base openings to the pathologic entities being approached. The transadnexal transorbital approach is especially rewarding in the described situation because of the extensive craniofacial reconstruction that the patient had previously undergone and the potential for serious complications following a more extensive procedure. Because of these benefits, we feel that increasing the scope of neuroendoscopic techniques, whether purely endoscopic or endoscopy-assisted, affords the surgeon in select cases the ability to reduce the morbidity typically associated with more standard procedures. Future research, whether case series or other reports describing both successful and unsuccessful use of endoscopic and other minimally invasive approaches to treat complex problems, will help to broaden the scope of acceptable alternative methods of treating similar problems. Conflict of interest The authors have no personal, financial, or institutional interest in any of the materials or devices described in this article.
References 1. Zimmer LA, Theodosopoulos PV (2009) Anterior skull base surgery: open versus endoscopic. Curr Opin Otolaryngol Head Neck Surg 17(2):75–78 2. Moe KS, Bergeron CM, Ellenbogen RG (2010) Transorbital neuroendoscopic surgery. Neurosurgery 67(3 Suppl Operative): ons16–28 3. Ciporen JN, Moes KS, Ramanathan D et al (2010) Multiportal endoscopic approaches to the central skull base: a cadaveric study. World Neurosurg 73(6):705–712 4. Beretta F, Andaluz N, Chalaala C et al (2010) Image-guided anatomical and morphometric study of supraorbital and transorbital minicraniotomies to the sellar and perisellar regions: comparison with standard techniques. J Neurosurg 113(5):975–981 5. Noggle JC, Scubba DM, Nelson C et al (2008) Supracilliary keyhole craniotomy for brain abscess debridement. Neurosurg Focus 24(6):E11 6. Abdel Aziz KM, Bhatia S, Tantawy MH et al (2011) Minimally invasive transpalpebral ‘‘eyelid’’ approach to the anterior cranial base. Neurosurgery 69(2 Suppl Operative):ons195–206 discussion 206-207
123
