Dwivedi JS *, Gupta AS **
(* Third Year Resident, ** Professor, Department of Obstetrics and Gynecology, Seth G.S. Medical College and K.E.M. Hospital, Mumbai, India)
Vestibular schwannoma occurs more commonly in females. Though it is infrequently seen during pregnancy the symptoms might be worsened. The early diagnosis followed by prompt treatment is very important. We present a case of multigravida with full term gestation referred to us with a large vestibular schwannoma.
Sir Charles Ballance performed the first successful surgery for a vestibular schwannoma in 1894. Since then many technological advancements have been made in the diagnosis and management of this tumor with varied symptoms. However the algorithm for management of cases detected in pregnancy still remains at a naive stage and needs to be studied further.
A 30 yr old G5P3L3A1 with 41 weeks of gestation with previous full term normal deliveries was referred to us from a private practitioner in view of recently diagnosed acoustic schwannoma for emergency cesarean section and further management. The patient was registered with the referring private practitioner from third month of gestation and had a regular follow up. The patient gave history of headache, blurring of vision, gait imbalance since fifth month of gestation which she did not consider important and did not inform the treating doctor. Fifteen days prior to presenting to us, patient had a fall due to imbalance for which she was investigated and an MRI from a private center diagnosed a 6.5 cm x 5.5 cm x 4 cm mass occupying the left cerebellopontine angle with compression of fourth ventricle and evidence of obstructive hydrocephalus. A neurosurgery opinion was taken at that hospital. She was advised to follow up after six weeks of delivery and the decision regarding mode of delivery was left to the obstetrician. A neurologist, neurosurgeon, and an ophthalmologist from our tertiary care center evaluated the patient clinically. She was diagnosed with bilateral papilledema and central nystagmus. She was started on injection mannitol 100 mg 6 hourly, and tablet acetazolamide twice daily. All other parameters were normal. Initially the neurosurgeon decided to operate and excise the tumor urgently and then allow the patient to go into spontaneous labor; however, the anesthetist denied fitness and recommended neurosurgery after delivery. The patient went into spontaneous, precipitate labor and uneventfully delivered a female child of 3.4 kg baby weight. There was no evidence of any coning. Post delivery the course in ward was uneventful. Subsequently the neurosurgeon decided to wait for 6 weeks after child birth for definitive surgery.
Cerebellopontine angle (CPA) is an area of neurological tissue. Tumor in this area might present with varied signs and symptoms. Any patient with unilateral sensorineural hearing loss or tinnitus should be evaluated for cerebellopontine angle tumor. Although the differential diagnosis for CPA tumors is quite large, the vast majority are vestibular schwannomas. Vestibular or acoustic schwannoma form 8 - 10% of the total intracranial tumors. These are encapsulated, benign, slow growing tumors with a growing rate of approximately 2 mm/ year. Symptoms are mostly produced due to the pressure on the surrounding neural tissue. Acoustic schwannoma seldom presents during pregnancy, however the symptoms of the same can be exaggerated or worsened during the pregnancy. The symptoms include tinnitus, hearing abnormalities and symptoms due to compression of the cerebellum and brain stem. These are mainly reported with large tumors as was also seen in our case. MRI imaging is the gold standard for vestibular schwannomas. Large tumors are difficult to manage. Surgical management of the tumor and delivery in the same sitting have not been reported in the literature. The recent treatment options include microsurgical excision, stereotactic radiosurgery or fractionated radiotherapy. In 1917, accelerated growth of vestibular schwannoma during pregnancy was first reported by Harvey Cushing. The correlation of increase in size of the tumor with the pregnancy led to research of presence of estrogen receptor (ER) on the tumor. ER α expression is increased in cases of sporadic vestibular schwannoma. There have been reported cases of operative management of acoustic schwannomas in pregnancy, however the preferred time is the second trimester. In our case the patient presented late at 41 weeks, and the difference of opinion between neurosurgeons and anesthetist delayed the neurosurgery. Patient soon went into spontaneous labor, hence operative management of the tumor was deferred till end of puerperium by the neurosurgeons. Patient did not develop any neurological complication during delivery or immediately postpartum leaving a point of thought, that these patients at full term pregnancy where dilemma exists about the mode of delivery, can be given a trial of labor in an institute where combined obstetric and neurosurgical emergency services are available. However to conclude that such modality can be of benefit requires further study.
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Dwivedi JS, Gupta AS. Acoustic Schwannoma In a Full Term Pregnant Patient JPGO 2015. Volume 3 No. 4. Available from: http://www.jpgo.org/2016/04/acoustic-schwannoma-in-full-term.html