Tuberculum sella meningioma: subfrontal approach

25 year old lady was complaining of progressive diminution of vision since the last two years and had been investigated elsewhere with a plain CT scan one year back following referral by her ophthalmologist. She had completely lost her vision one year back during the last few months of pregnancy before the delivery of her first child. She has no other complaints.

On examination, she had no perception of light in either eye. Fundi had bilateral primary optic atrophy. There were no other deficits.

Plain CT scan [pvt film] showed a very ill defined small isodense suprasellar lesion. MRI showed a T1 isointense, T2 hyperintense lesion based on the tuberculum sellae stretching the optic nerve and chiasm. Lesion measured 3.0 X 2.6 X 2.3 cm. It was enchancing uniformly and brightly on Gad contrast. CT angiogram showed that the internal cerebral arteries and anterior cerebral arteries were stretched out but not encased by the lesion.

Since there was little possibility of recovery of vision even after microsurgical removal of the tumor in view of long standing total visual loss and established optic atrophy, she was strongly encouraged to consider the option of getting Gammaknife radiosurgery at concessional rate at another hospital. However, she and her husband chose to have microsurgery. She had developed phenytoin rash prior to surgery and anticonvulsant treatment was switched over to sodium valproate.

On 8/04/08 she underwent bifrontal craniotomy, sub frontal approach and complete excision of the lesion. ^{[M.S. Gopalakrishnan, V.S. Hari, Balasubramanium]} A sinusoidal bicoronal stealth incision was used for good cosmesis. An initial pterional transylvian approach had to be changed to bilateral subfrontal approach in view of technical (maneuvering) difficulties encountered with the available operating microscope. The lesion was firm and moderately vascular. A very small part of the lesion which was densely adherent to the left ICA was coagulated. The dural attachment was also coagulated. [Simpson’s grade 2 excision] The stretched out film-like, translucent chiasma and the thickened fibrous looking optic nerves were preserved. Olfactory tracts got severed during surgery. The right tract was sutured back with 80 prolene. Dura was closed with pericranial patch.

Patient developed drowsiness on post operative day eight which improved with intensification of antiedema measures. Post op CT scan showed complete excision of the lesion. Bilateral basifrontal edema was present [retraction induced]. Pseudo-meningocele was aspirated and pressure dressing was given. At the time of discharge, she is afebrile, and well oriented. However she has increased talkativeness which may be due to mild frontal disinhibition due to frontal lobe retraction. This is expected to resolve.

Histopathology report is menigothelial meningioma [WHO grade 1]

Discussion:

Although she had been investigated following complaints of progressive visual loss during pregnancy, an appropriate diagnosis was not made despite visits to many other hospitals. This was partly due to the fact that only a plain ct scan was done which was not clearly showing the lesion. She had been completely blind for many months before referral here. In the circumstance of long standing visual loss and optic atrophy, where saving or recovering visual function is not a consideration, gammaknife radiosurgery would have been a less invasive and effective option. However, patient and her husband chose to undergo microsurgical excision of the lesion. Although her vision is highly unlikely to improve, she and her husband remain hopeful

The plain scan:

Lacrimal gland adenoid cystic carcinoma recurrence

64 year old gentleman was diagnosed to have lacrimal gland adenoid cystic carcinoma following excision of a mass under the right eyebrow, via lateral orbitotomy, done in a hospital elsewhere in March 2004. Following that he presented in ophthalmology OPD with a firm lobulated mass in right eye below eyebrow. A biopsy was done, which confirmed the diagnosis. He completed radiotherapy in 23/12/08 since further surgery was deemed not possible at that time.

[40 cGy in 20 fractions, field size 15X6 cms to right eye, tumor depth 4 cms, 24 cGy in 12 fractions, right anterior and right lateral fields with wedges and left eye shielded].

In 24/1/07, the tumor recurred. [FNAC 572/07] and in 24/06/07 he underwent local re-excision of the mass.

In 28/1/08 he presented with pain and bleeding from right eye and was evaluated with a CT scan which showed tumor recurrence. He had undergone cataract excision and intraocular lens placement in left eye in 12/2/08. On examination he had a firm mass felt under the lateral aspect of right eyebrow, with surrounding edema causing ptosis and chemosis in right eye. There was no useful vision in right eye.

Ct scan had revealed an enhancing lesion in the right orbit lateral to the globe which was eroding the roof and lateral wall of the orbit. Metastatic work up was negative.

On 23/2/08 he underwent exenteration of the right orbit^[ophthal], followed by excision of the roof and lateral walls of the orbit after a right fronto-temporal craniotomy ^{[neurosurgery}. The firm tumor, the involved orbital ridge and a margin of bone up to the orbital apex were excised. A few areas of inadvertent dural tears were repaired using pericranial patch. Frontal sinus was exteriorized. Temporalis muscle was placed in the socket and a local rotation flap was used to cover the bare socket. ^[plastic] Post operatively he had a few episodes of CSF rhinorrhea which settled with lumbar drainage.

Post op CT scan had showed complete excision of the tumor and bone excision up to the orbital apex.

After one and half months of discharge from hospital he presented with purulent discharge from right nostril with tenderness in right maxillary sinus area. This was treated with sinus washes and antibiotics. He complained of occasional episodes of clear watery discharge from right nostril suggestive of CSF rhinorrhea. This tended to occur in right lateral position as he gets up from sleep.

He was re-admitted for evaluation and treatment of possible CSF rhinorrhea. An MRI with Ciss 3d sequence could not reliably pick up a site of leak. So he underwent lumbar puncture and intra-thecal contrast cisterography in prone position to identify site of leak. This investigation also failed to reveal a leak. He was on lumbar csf drainage for five days prior to contrast cisternography . The CSF sample which was taken on the last day prior to removing the catheter had plenty of pus cells and grew acinetobacter sensitive to meropenam, amikacin , ceftazidime and ciprofloxacin. He also had headache and mild meningeal signs. Meningeal signs and fever settled with meropneam [given initially for three days] and other sensitive antibiotics. Csf leak also disappeared.

At discharge he is afebrile, ambulant and comfortable.

Discussion:

Patient had recurrence of lesion after initial surgery, radiation therapy and re-excision. An oncologically adequate resection required excision of the tumor and in addition, the involved orbital bone with adequate margins. This necessitated a fronto-temporal craniotomy followed by excision of the roof and lateral walls of the orbit up to the orbital apex after exenteration of the eye. This should maximize the chances of complete tumor excision and minimize risk of further recurrence of this type of highly malignant tumor.

Symptoms suggestive of delayed leak were reported by the patient. However the site of the leak could not be ascertained by either a ciss 3d sequence of mri or by contrast cisternogram. Hence a direct repair could not be carried out. Also the leak never occurred during hospital stay after initiation of csf drainage. It is possible that the leak is not detected since it is intermittent. Patient developed meningeal signs after removal of the csf catheter [iatrogenic or as a result of unapparent csf rhiorrhea]. This resolved within a day of starting antibiotics. Also the leak seems to have spontaneously resolved. If leak recurs in future, a lumboperitoneal shunt procedure may be carried out as site of leak is obscure to do an anatomical repair. Intradural exploration, re-exterioirization of frontal sinus, anterior fossa carpeting with a large pericranial or fascia lata graft can also be considered as an alternative.

He requires careful and regular imaging follow up to rule out tumor recurrence.