Endoscopic endonasal cyst fenestration into the sphenoid sinus using the mucosa coupling method for symptomatic Rathke's cleft cyst: a novel method for maintaining cyst drainage to prevent recurrence

OBJECTIVE

Rathke's cleft cyst (RCC) is a benign cystic lesion with a relatively high incidence of local recurrence that occasionally requires repeat surgery. To prevent recurrence, simple cyst fenestration and drainage of the cyst contents to the sphenoid sinus is recommended, but it occasionally recurs. The authors postulated that obstruction of fenestration is a main cause of recurrence, and they developed a method, named the "mucosa coupling method (MC method)," that maintains persistent drainage. In this method, the RCC epithelium and the mucosa of the sphenoid sinus are connected, which promotes re-epithelialization between the two epithelia, maintaining persistent drainage. The outcome of this method was compared with that of conventional cyst fenestration.

METHODS

In a consecutive series of 40 patients with RCC, the surgical strategy was changed during the study period: from December 2009 to September 2014 (the conventional period), 24 patients were scheduled to be treated using the conventional fenestration method, whereas from September 2014 to September 2017 (the MC period), 16 patients were scheduled to be treated using the MC method. However, because of an intraoperative CSF leak, the fenestration was closed during surgery in 3 patients in the conventional period and 2 in the MC period; therefore, these 5 patients were excluded from the analysis. Twenty-one patients treated with the conventional fenestration method (conventional group) and 14 patients treated with the MC method (MC group) were analyzed. All patients regularly underwent MRI after surgery to detect reaccumulation of cyst contents. The rate of reaccumulation with and without reoperation, visual outcomes, endocrinological outcomes, and postoperative complications were compared between these two groups.

RESULTS

The median follow-up period in all 35 patients was 48.0 months (range 1-96 months), 54.0 months (range 1-96 months) in the conventional group and 35.5 months (range 12-51 months) in the MC group. No reaccumulation was detected on MRI in the 14 patients in the MC group, whereas it was noted in 9 (42.9%) of 21 patients in the conventional group, and 2 of these 9 patients required repeat surgery. There were no significant differences in visual and endocrinological outcomes and complications between these two groups.

CONCLUSIONS

The MC method for RCC is effective for preventing obstruction of cyst fenestration, which contributes to preventing cyst reaccumulation. Furthermore, this method is equivalent to the conventional fenestration method in terms of visual and endocrinological outcomes and the complication rate.

Mucocele formation under pedicled nasoseptal flap

The pedicled nasoseptal flap has become an indispensible tool for the reconstruction of skull base defects. This flap is easily harvested, provides a large surface area of vascularized tissue, and has few reported complications. We describe the case of a 60-year-old man who underwent endoscopic, endonasal transsphenoidal surgery with septal flap reconstruction who developed a sphenoid sinus mucocele postoperatively. We also have reviewed the literature for similar findings and discuss this complication in the setting of pituitary surgery and endoscopic skull base repair. Although likely a rare occurrence, mucocele formation after septal flap reconstruction should be recognized and monitored with postoperative nasal endoscopy and radiologic imaging. Reoperation or mucocele drainage may be necessary if symptomatic or in cases of rapid enlargement.

Sphenoid sinus pyocele after transsphenoidal approach for pituitary adenoma

Transsphenoidal pituitary adenoma surgery is related to a low morbidity rate. The complications that can occur are classified as intra- and extracranial. The aim of the study is to discuss one group of these complications involving the sphenoid sinus: mucocele and its possible transformation into pyocele. We evaluate clinical presentation, management strategy and the outcome after long-term follow-up presenting an explicative case and a review of the literature. A patient presented to our outpatient clinic 8 months after transsphenoidal surgery for selective removal of a pituitary adenoma because of an acute onset of frontal headache during an airplane travel, fever and pulsating sensation in left eye and ear. MRI revealed a contrast-enhancing lesion in the left inferior portion of the sphenoid sinus. An endonasal endoscopic revision of the sphenoid sinus was performed. After opening of the scar to enter in the left sinus a pyocele was found and treated with drainage and marsupialisation. Development of sphenoid sinus pyocele is an extremely rare postoperative complication of transsphenoidal surgery. This lesion should be taken in consideration in patients presenting with retroorbital headache of acute onset and fever after pituitary surgery. Diagnosis can be suspected on the MRI studies and confirmed by a targeted flexible endoscope examination. Endoscopic drainage with wide opening of the sphenoid sinus and marsupialisation is the treatment of choice to avoid recurrences.

Sphenoethmoidal mucocele masquerading as trochlear palsy

Acquired vertical strabismus is commonly caused by superior oblique muscle palsy, often resulting from blunt head trauma or vascular problems, and less often from brain tumors, meningitis, and aneurysms. To date, mucoceles in the ethmoid sinus have rarely been reported as a cause for superior oblique muscle palsy. We report a case of trochlear nerve palsy and subsequent optic neuropathy caused by a mucocele in the ethmoid and sphenoid sinuses.

T1 signal hyperintensity in the sellar region: spectrum of findings

T1 signal hyperintensity is a common finding at magnetic resonance imaging of the sellar region. However, this signal intensity pattern has different sources, and its significance depends on the clinical context. Normal variations in sellar T1 signal hyperintensity are related to vasopressin storage in the neurohypophysis, the presence of bone marrow in normal and variant anatomic structures, hyperactive hormone secretion in the anterior pituitary lobe (eg, in newborns and pregnant or lactating women), and flow artifacts and magnetic susceptibility effects. Pathologic variations in T1 signal hyperintensity may be related to clotting of blood (in hemorrhagic pituitary adenoma, pituitary apoplexy, Sheehan syndrome, or thrombosed aneurysm) or the presence of a high concentration of protein (Rathke cleft cyst, craniopharyngioma, or mucocele), fat (lipoma, dermoid cyst, lipomatous meningioma), calcification (craniopharyngioma, chondroma, chordoma), or a paramagnetic substance (manganese, melanin). After treatment, T1 signal hyperintensity may result from the presence of materials used for surgical packing (gelatin sponge, fat); from compression of the cavernous sinus and reduction of the venous flow, caused by overpacking of the operative bed; or from hormone hypersecretion by a remnant of normal tissue in the anterior lobe of the pituitary gland.