Journal ofNeurology, Neurosurgery, and Psychiatry 1991;54:463-465 4L63 Neurosurgical complications after intranasal J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.54.5.463 on 1 May 1991. Downloaded from ethmoidectomy Richard M Toselli, Anne dePapp, Robert E Harbaugh, Richard L Saunders Abstract right frontal lobe haematoma with blood in Intranasal ethmoidectomy is a common the suprasellar cisterns and interhemispheric otolaryngological procedure. Despite the fissure. Neurosurgical consultation was potential for serious intracranial com- obtained. A ventricular drain was placed and plications, there is a paucity of reports antibiotics were started. describing the neurosurgical complica- One week after surgery, the patient was tions of the procedure. Two patients with transferred to our institution with a clinical intracranial complications of intranasal picture of florid meningitis. A CT scan ethmoidectomy, and the relevant showed increasing pneumocephalus with a medical literature, are reviewed. The large collection of air in the right lateral ven- anatomy of the ethmoid air cells and tricle. A right frontal craniotomy with fascia their relation to the intracranial cavity lata graft repair of the basal skull defect was are described. The importance of defin- carried out. Cerebrospinal fluid cultures grew itive, emergent repair with attention to Candida albicans; the patient received a full the potential for vascular injury is course of intravenous and intrathecal discussed. amphotericin B plus broad spectrum anti- bacterial parenteral antibiotics. Although his meningitis resolved, the patient made little Intranasal ethmoidectomy is a common neurological improvement and was trans- otolaryngological procedure performed for the ferred to a nursing home. treatment of chronic ethmoiditis with or with- He was admitted two months later for the out polyposis, for acute complicated treatment of an extradural tension pneumo- ethmoiditis, and for biopsy of suspected cephalus.3 A right external ethmoidectomy, a ethmoid sinus tumours. The procedure offers substitute dural graft to the posterior ethmoid certain advantages over external and intraoral and sphenoid sinuses, and aspiration of approaches, because it avoids the incisions extradural air through an existing burr hole and complications of these approaches and were performed. He also required ventri- improves visualisation of the ethmoid air culoperitoneal shunting for hydrocephalus. cells.' However, in the early twentieth century One year after surgery the patient is at home, Mosher described intranasal ethmoidectomy alert, conversant, and intermittently confused http://jnnp.bmj.com/ as one of "the most dangerous and blindest of with a flat affect. all surgical operations".2 Despite the potential for intracranial complications during Case 2 ethmoidectomy, there is a paucity of reports A 65 year old white woman with a history of describing the neurosurgical complications of chronic sinusitis and numerous rhinological this procedure. procedures had a transnasal ethmoidectomy at The two cases described were referred to another institution. Excessive bleeding and on September 28, 2021 by guest. Protected copyright. Section of the neurosurgical service of the Dartmouth- transient hypotension were noted at surgery. Neurosurgery, Hitchcock Medical Center and illustrate Postoperatively, the patient was difficult to Department of serious Surgery, Dartmouth- intracranial complications of intra- arouse, and a CT scan demonstrated a large Hitchcock Medical nasal ethmoidectomy. These cases prompted a cribriform plate defect, intracranial air fron- Center, Hanover, New review of the medical literature and suggested tally and temporally, and intraventricular Hampshire, USA the of a more R M Toselli adoption aggressive treatment haemorrhage involving both lateral ventricles R E Harbaugh strategy for treating patients with these and the third ventricle. The patient was trans- R L Saunders problems. ferred to the neurosurgical service at the Department of Dartmouth-Hitchcock Medical Center for Medicine, Brigham Case 1 further evaluation. A left frontal craniotomy and Women's A 70 year man Hospital, Boston, old white had numerous nasal was carried out as an emergency repair of the Massachusetts, USA operations for treatment of allergic rhinitis, anterior fossa defect. Life-threatening bleed- A dePapp chronic sinusitis and recurrent nasal polyps. A ing was noted when some of the nasal packing Correspondence to: transnasal ethmoidectomy/sphenoidectomy from the floor of the anterior fossa was Dr Toselli, was Section of Neurosurgery, complicated by perforation of the roofs of removed. The left frontal pole was removed Dartmouth-Hitchcock the ethmoid and right sphenoid sinuses. The and aneurysm clips were placed on the left Medical Center, 2 Maynard patient did not awaken Street, Hanover, readily from surgery, fronto-polar artery. A fascia lata/muscle graft New Hampshire 03756, USA and on the second postoperative day remained was used to obliterate the basal skull defect. Received 21 August 1989 obtunded and became febrile. Skull CT Postoperatively, the patient developed and in revised form revealed an 8 x 10 mm 19 July 1990. deficit in the roof of the cerebrospinal rhinorrhoea and required Accepted 21 August 1990 ethmoid sinus. A CT scan demonstrated a revision of the anterior fossa repair; ultimately 464 Toselli, dePapp, Harbaugh, Saunders she required a ventriculoperitoneal shunt. lamina papyracea. The air cells are usually J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.54.5.463 on 1 May 1991. Downloaded from One month after this last operation the patient divided into two groups based on their drainage was awake, alert, following commands, and pattern: an anterior group and a posterior demonstrating a frontal lobe affect. group. The anterior cells drain under the cover of the middle turbinate, and the posterior cells drain under the superior turbinate. Both the Discussion superior and middle turbinates are components The ethmoid bone is a complex bone that has of the ethmoid bone. both intracranial and intranasal components The middle turbinate is the landmark for (fig 1). Intracranially, the crista galli forms a intranasal ethmoidectomy. Anteriorly, it is midline strut anchoring the falx cerebri. The continuous with the ethmoid roof and attaches cribriform plate is perforated by the olfactory between the cribriform plate and fovea Coronal section nerves and the anterior ethmoidal arteries and ethmoidalis. Therefore, dissection lateral to the Figure 1 Coronal abuts the crista galli laterally. The cribriform middle turbinate prevents violation of the drawing of ethmoid air plate is the most dependent portion of the cribriform plate. Posteriorly, the middle cells showing their relation anterior cranial fossa. The fovea ethmoidalis is turbinate has no attachment to the anterior to cribriform plate. the solid bone that ascends approximately 3- cranial fossa. The middle turbinate is 4 mm laterally from the cribriform plate and frequently pneumatised and involved in dis- forms the roof of the ethmoid air cells laterally ease. This may require its removal, but every and posteriorly. Medially and anteriorly, the effort to preserve the middle turbinate roof of the air cells is formed by the cribriform landmarks is made by experienced otolaryn- plate. The perpendicular plate ofthe ethmoid is gologists. This preservation is crucial, as most the inferior midline extension of the crista galli of the afflicted patients require further nasal and contributes to the bony midline septum. procedures, and scarring can obscure normal The air cells are pyramidal in shape with landmarks. Both of the patients described their bases situated posteriorly. Their medial above had previous nasal procedures. wall forms the lateral wall of the nasal cavity. Two other anatomical areas are potential They are 4-5 cm in length, 2-3 cm in height, sources of complication. The lamina papyracea and 0 5-1 5 cm in width from front to back.4 At is a thin slip of bone separating the anterior birth, they are the most fully developed air ethmoid cells from the orbit. Perforation ofthis cells; hence children usually present with bone can result in serious orbital trauma ethmoiditis when suffering complications of including medial rectus injury. The posterior sinusitis.5 It is believed that embryologically ethmoid cells, in their most posterior extent are the other paranasal sinuses are extensions ofthe within 1 mm of the optic nerve as it travels ethmoid air cells. The frontal and maxillary through the sphenoid bone. There have been sinuses arise from the anterior ethmoid cells reports of the optic nerve travelling through a and the sphenoid sinus emanates from the completely pneumatised sphenoid bone.4 The posterior cells. The ethmoid air cells are optic nerve is then anatomically inside the separated from the orbit laterally by the thin posterior ethmoid air cell labyrinth. Because of the anatomical relationships of the ethmoid bone, intranasal ethmoidectomy http://jnnp.bmj.com/ carries with it a potential for serious intra- ...I cranial complications. The scepticism about the approach was allayed by Freedman and Kern in 1979, when they reviewed 1000 con- secutive cases from 1957-72 with an overall complication rate of 2 8% without mortality or blindness.6 The two most serious compli- cations were meningitis and cerebrospinal on September 28, 2021 by guest. Protected copyright. rhinorrhea. In 1982, Taylor