Comparative study of sella closure with autologous free fat graft only in intra operative CSF leak

Transcription

1 Original Article Comparative study of sella closure with autologous free fat graft only in intra operative CSF leak ABSTRACT Objective Muhammad Burhan Ud din Janjua, Inayat Ullah Khan Department of Neurosurgery, Shifa International Hospital, Islamabad, Pakistan. To present the local experience of fat graft use for sella closure in case of intraoperative CSF leak to prevent the post operative CSF rhinorrhea. Patient and Methods We retrospectively studied 22 cases operated for pituitary adenomas from 2004 to Transsphenoidal hypophysectomy was performed with construction of sella floor with autologous free fat graft in patients with intraoperative CSF leak. All patients were followed after one, three and six month of surgery. The out come was assessed by follow up MRI scan. Results Male to female ratio was 2:1 and age of patients ranged from 15 to 74 years (mean 46 years). Intraoperative CSF leakage was observed in 8 cases. No post operative CSF leakages was observed in any one. Three out of 22 patients had microadenoma while rest had macroadenoma. Only 5 patients had functioning adenoma. 4 had prolactinoma and 1 each had growth hormone producing adenoma and ACTH producing adenoma. Post operative complications were noted in 13 patients. Only 2 patients had revision procedure done. Conclusion The technique of covering the sella membrane and dural defects with the use of free fat graft in the case of intraoperative CSF leakage appeared to be most reliable and cost effective technique for intraoperative CSF leak. (Rawal Med J 2010;35: ). Key words Sella closure, Free fat graft, Transsphenoidal surgery.

2 INTRODUCTION For surgical management of pituitary adenoma, transsphenoidal approach has been a major technique since 1960s. With the development of technical possibilities and increase in surgeons expertise, mortality and morbidity after such interventions have decreased. Postoperative cerebrospinal fluid (CSF) leakage, however, remains the most serious and life-threatening complication. Its rate has been reported to vary from 1 to 6%. 1-4 Frequent occurrence of intraoperative CSF leakage also poses an important problem, being reported in 15 to 30% of cases. 3,4 Various techniques for packing the sella turcica and closing the CSF leakage have been advocated by different authors. Although in the past decades, transsphenoidal approach has remained the major method in pituitary surgery, neither the risks of intraoperative and postoperative CSF leakage nor its closure techniques have been adequately evaluated. No unanimous agreement has been reached so far as to the techniques of closing the CSF fistula and the sella turcica defect. The aim of the present study was to present the experience of one of the methods used for sella floor closure to prevent intra- and postoperative CSF leaks. PATIENTS AND METHODS At Shifa International Hospital 22 patients underwentgone pituitary adenoma surgery by applying transsphenoidal approach. This retrospective case study was done with non randomized convenience sampling. All patients underwent pre and postoperative endocrinological and ophthalmological examination. Interseptal nasal approach was applied in all patients who under went transphenoidal hypophysectomy. No visual evidence of the remaining tumor mass and no preoperative radiological evidence which would allow us to suspect the infiltration of cavernous sinuses, were found. In the case of intraoperative CSF leakage, the sella was closed using one method consisted of packing the sella and sphenoidal sinus with autologous free fat and restoring the bone defect of the sella. 5 Rupture of septal mucosa, postoperative CSF leakage, endocrine complications, such as hypopituitarism, diabetes insipidus, and infectious complications, such as sinusitis, meningitis, and deterioration of vision acuity were considered as postoperative complications. A tumor was considered to be totally removed when a descended membrane of sella turcica was visualized. The tumor, its recurrence, radiological data, removal procedure, and CSF leakage during surgery were recorded. The follow-up of the patients was performed by an endocrinologist and a neurosurgeon. Statistical analysis was performed by using SPSS/10.0. Differences were considered statistically significant when the P values were <0.05. RESULTS A microadenoma was diagnosed in 3 (13.6 %) and macroadenoma in 19 (86.36%) cases. Rest of results are summarized in the table 1,2 and 3 below;

3 Table 1. Demographic characteristics and surgical outcome of patients (n=22). Number Percentage Gender Male % Female % Mean Age in years 46 Type of adenoma Macroadenoma % Microadenoma % Hormonal excess Prolactin % Growth hormone % ACTH Visual defects Right eye % Left eye % Bilateral eye % Other symptoms Coarse fascial features % Balance disturbance % Electrolyte imbalance Hyponatermia % N = 22 Operating surgeon Surgeon himself All 100%

4 Surgical resident 0 0 DISCUSSION Transsphenoidal surgery is a reasonably safe procedure, with a mortality rate of less than 1%, in our study it being 0% because of small study sample. The numbers of intra- and postoperative complications in our study were quite low. We correlated CSF leakage with various types of adenomas. In our study, patients with prolactin producing adenoma were observed to have an increased incidence of intraoperative CSF leakage. There was significant difference in size between prolactin producing adenomas and other types of adenomas. It may be assumed, therefore, that CSF leakage risk arises due to changes in the membrane of sella turcica resulting from the progressive increase in adenoma size with resultant thinning of the bone. However, this remains to be further proved by histological studies. In our opinion, special attention should be given to the identification of CSF leakage during surgery for prolactin producing adenomas. Table 2. Management of Per-operative CSF rhinorrhea (n=8). With fat free graft 9 41% Without fat free graft % Revision procedure Transsphenoidal 2 9% According to the American National Survey 2 postoperative sphenoidal sinusitis occurred with an incidence of 8.5%. We observed none of such complication. Nevertheless, we noted inflammation of the sphenoidal sinus, after packing with autologous free fat graft. We noted that packing the sphenoidal sinus with fat did not increase risk of postoperative sphenoiditis; that was the reason why we used this method. Although in the past decades transsphenoidal approach has remained the major method in pituitary surgery, neither the risks of intraoperative and postoperative CSF leakage nor its closure techniques have been evaluated adequately. In our study, we applied this technique and studied its various effects and found that only one case of meningitis after the procedure. Table 3. Postoperative complications after surgery (N=22).

5 Complication N % Hypopituitarism % Rupture of septal mucosa 0 0 Deterioration of vision % Sinusitis 0 0 Postoperative CSF rhinorrhea 0 0 Meningitis % Transitory diabetes insipidus Permanent diabetes insipidus % 0 0 Transitory SIADH % Permanent SIADH 0 0 Paresis n. oculomotorius 0 Intraventricular hemorrhage 0 0 There exist numerous opinions and methods regarding the sella closure. Some authors advocate sella closure only in severe intraoperative CSF leakage 6,7 as we did in our patients when they were found to have large tumor with intraoperative CSF leakage as per operative finding while others recommend it in all occasions. 8,9 There are many materials and techniques used for this autologous dura and fibrin glue, synthetic dura, synthetic vicryl, silicone plate, alumina ceramic and others Only one sella closure method of all described above was used in our study. We were packing the sella turcica with autologous free fat graft. But recent practice by neurosurgeons is to place Surgicel on the defect of sella membrane and a TachoSil plate on top of it, then pack the sella with autologous fat, cover autologous free fat graft with Surgicel and TachoSil intradurally, and place TachoSil on the dura mater defect, and cover TachoSil plate with Surgicel. 15,16 In the case of CSF leakage, the majority of authors emphasize the necessity to restore the defect of sella with autologous bone graft or cartilage 11,12 as we did in most of our cases. During repeatedly performed surgeries it has been observed that TachoSil plate was overgrown by collagen fibers of connective tissue, so in our opinion additional repair of the sella floor is not necessary. According to the data, different authors who applied various methods of sellar defect plastic, postoperative CSF leakage rate ranged from 1% to 6% [1-8],

6 whereas using our simple method, in 9 patients of intraoperative CSF leakage we had only 1 case with postoperative CSF leakage. In our opinion, closing the sella membrane and packing sella turcica with fat is a technically simple and reliable method. Still, in the case of intense intraoperative CSF leakage, lumbar drainage of CSF is essential. CONCLUSION Sella floor closure with autologous free fat graft is a useful and rewarding technique to close the sella turcica defect in the presence of intraoperative cerebrospinal fluid leak. Correspondence: Dr Inayat Ullah Khan, Consultant Neurosurgeon. Tel: (92-51) inayatkhan58@gmail.com Received: September 10, 2009 Accepted: December 3,2009 REFERENCES 1. Black PM, Zervas NT, Candia GL. Incidence and management of complications of transsphenoidal operation for pituitary adenomas. Neurosurgery 1987;20: Ciric I, Ragin A, Baumgartner C, Pierce D. Complications of transsphenoidal surgery: results of national survey, review of the literature, and personal experience. Neurosurgery 1997;40: Shiley SG, Limonadi F, Delashaw JB, Barnwell SL, Andersen PE, Hwang PH, et al. Incidence, etiology, and management of cerebrospinal fluid leaks following trans-sphenoidal surgery. Laryngoscope 2003;113: Shimon I, Ram Z, Cohen Z, Hadani M. Transsphenoidal surgery for Cushing s disease: endocrinological follow-upmonitoring of 82 patients. Neurosurgery 2002;51: Freidberg SR, Hybels RL, Bohigian RK. Closure of cerebrospinal fluid leakage after transsphenoidal surgery: technical note. Neurosurgery 1994;35: Sonnenburg RE, White D, Ewend MG, Senior B. Sellar reconstruction: is it necessary? Am J Rhinol 2003;17: Sinkūnas K, Draf W, Deltuva V, Matukevicius A, Rastenyte D, Vaitkus S, et al. Management of cerebral fluid leak after surgical removal of pituitary adenomas. Medicine (Kaunas). 2008;44(4): Ciric I, Rosenblatt S, Zhao J-Ch. Transsphenoidal microsurgery (operative nuances). Neurosurgery 2002;51: Jane JA Jr, Thapar K, Kaptain GJ, Martens N, Laws ER Jr. Pituitary surgery: transsphenoidal approach (operative nuances). Neurosurgery 2002;51:

7 10. Kabuto M, Kubota T, Kobayashi H, Takeuchi H, Nakagawa T, Kitai R, et al. Long-term evaluation of reconstruction of the sellar floor with a silicone plate in transsphenoidal surgery. J Neurosurg 1998;88: Koszewski W. Easy sellar reconstruction in endoscopic endonasal transsphenoidal surgery with polyester-silicone dural substitute and fibrin glue: technical note. Neurosurgery 2002; 50: Kubo Sh, Inni T, Hasegawa H, Yoshimine T. Repair of intractable cerebrospinal fluid rhinorrhea with mucosal flaps and recombinant human basic fibroblast growth factor: technical case report. Neurosurgery 2005;56: Cappabianca P, Cavallo LM, Colao A, de Divitiis E. Surgical complications associated with the endoscopic endonasal transsphenoidal approach for pituitary adenomas. J Neurosurg 2002;97: Liu JK, Orlandi RR, Apfelbaum RI, Couldwell WT. Novel closure technique for the endonasal transsphenoidal approach. J Neurosurg 2004;100: Guity A, Young PH. A new technique for closure of the dura following transsphenoidal and transclival operations. Technical note. J Neurosurg 1990;72: Mortini P, Losa M, Barzaghi R, Boari N, Giovanelli M. Results of transsphenoidal surgery in a large series of patients with pituitary adenoma. Neurosurgery 2005;56: