Impact of calcineurin-inhibitor conversion to mTOR inhibitor on renal allograft function in a prednisone-free regimen.

Traditionally, chronic calcineurin inhibitor (CNI) nephrotoxicity has been considered to be one of the main nonimmune mechanisms causing chronic renal allograft dysfunction. CNI minimization and withdrawal strategies have yielded inconsistent results. Few studies address the feasibility of CNI elimination in a prednisone-free regimen. We report a prospective, randomized trial in 200 patients evaluating the impact on renal function and incidence of acute rejection after conversion from tacrolimus (Tac) to sirolimus (SRL). Patients with recent (<3 months) acute rejection episodes or with >0.5 g/day of proteinuria were excluded. All were induced with alemtuzumab, underwent rapid steroid elimination and were maintained on mycophenolate mofetil and Tac. At 12 months posttransplant, patients were randomized 2:1 to SRL (n = 123) or maintained on Tac (n = 64). Mean follow-up was 41.1 ± 15.8 months in the SRL group and 40.7 ± 14.4 months in the Tac group. Biopsy-proven acute rejection at 24 months postrandomization was similar between the groups. Patient survival, graft survival and estimated GFR were also not statistically different. Our study demonstrates that in a prednisone-free immunosuppressive regimen, conversion from Tac to SRL at 12 months posttransplantation is not associated with increased rates of acute rejection and graft loss. However, despite CNI elimination, renal allograft function is equally maintained in both groups.

Fusion technique for liver transection with Kelly-clysis and harmonic technology.

BACKGROUND: Various devices are available for liver transection and comparative data on transection techniques are limited by the diversity of operative procedures. Clamp crushing (Kelly-clysis) with a Cavitron ultrasonic surgical aspirator (CUSA-Integra Radionics) is widely used for splitting the liver parenchyma. Hemostasis is achieved by bipolar coagulation, ligatures, or hemoclips. We introduce a fusion technique (Focus-clysis) for liver transection using a combination of Kelly-clysis and harmonic technology. MATERIALS AND METHOD: A fusion technique (FT) was performed using FOCUS, a Kelly clamp like instrument attached to a Harmonic generator. Hepatic resections (nine major, nine minor) were performed with the fusion technique in 18 non-cirrhotic patients. Variables evaluated were blood loss, transection time, biliary leak, postoperative liver function, morbidity, and cost-effectiveness. The results were compared with 18 hepatic resections (nine major, nine minor) that were performed with our earlier technique, i.e., CUSA with bipolar cautery, ligatures, and hemoclips. RESULTS: The mean blood loss was 416 ml in the FT group, compared to 833 ml in the CUSA group. Two patients in the FT group needed blood transfusion in the first 48 h, whereas eight patients in the CUSA group had transfusions. No major postoperative liver dysfunction was noted with the new technique, and postoperative morbidity was lower in the FT group. Liver transection with the fusion technique was faster. CONCLUSION: The fusion technique (Focus-clysis) using Kelly-clysis and harmonic technology is promising, easy, and effective for liver transection. Our initial results show advantages over the routinely used CUSA/bipolar combination. The fusion technique could be a new option for liver transection, especially in non-cirrhotic patients.

Characterization of intracranial mass lesions with in vivo proton MR spectroscopy.

PURPOSE: To assess the use of in vivo proton MR spectroscopy for characterization of intracranial mass lesions and to ascertain its reliability in grading of gliomas. METHODS: One hundred twenty patients with intracranial masses were subjected to volume selective spectroscopy using stimulated echo acquisition mode (echo time, 20 and 270 milliseconds) and spin echo (echo time, 135 milliseconds) sequences. The intracranial lesions were grouped into intraaxial and extraaxial, as judged with MR imaging. Assignment of resonances was confirmed in two samples each of brain abscess, epidermoid cyst, and tuberculoma using ex vivo high-resolution MR spectroscopy. RESULTS: The in vivo spectra appeared distinct compared with normal brain in all the cases. All high-grade gliomas (n = 37) showed high choline and low or absent N-acetyl-L-aspartate and creatine along with lipid and/or lactate, whereas low-grade gliomas (n = 23) were characterized by low N-acetyl-aspartate and creatine and high choline and presence of only lactate. N-acetyl-aspartate/choline ratio was significantly lower and choline/creatine ratio was significantly higher in high-grade gliomas than in low-grade gliomas. Presence of lipids suggested a higher grade of malignancy. All metastases (n = 7) showed lipid and lactate, whereas choline was visible in only four cases. Epidermoids showed resonances from lactate and an unassigned resonance at 1.8 ppm. Meningiomas could be differentiated from schwannomas by the presence of alanine in the former. Among the infective masses, pyogenic abscesses (n = 6) showed resonances only from cytosolic amino acids, lactate, alanine, and acetate; and tuberculomas (n = 11) showed only lipid resonances. CONCLUSIONS: In vivo proton MR spectroscopy, helps in tissue characterization of intracranial mass lesions. Spectroscopy is a reliable technique for grading of gliomas when N-acetyl-aspartate/choline and choline/creatine ratios and presence of lipids are used in combination.

Primary intraosseous orbital hemangioma: a case report and review of the literature.

Primary intraosseous orbital hemangiomas are rare tumors. Only 25 cases have been reported in the literature. Very few of them have multiple orbital bone involvement. We report a case with extensive involvement of the orbital roof, the medial and lateral walls of the orbit, and the lesser and greater wings of the sphenoid, and describe a unilateral extradural frontotemporal approach to excise the tumor and decompress the right superior orbital fissure and both optic nerves. A brief clinical and radiological review of the literature is presented.

Posterior occipitoaxial fusion for atlantoaxial dislocation associated with occipitalized atlas.

Between 1989 and 1994, 50 patients suffering from congenital atlantoaxial dislocation with either an assimilated atlas or a thin or deficient posterior arch of the atlas were treated with occipitocervical fusion using the technique described by Jain and colleagues in 1993 with a few modifications. An artificial bridge created from the occipital bone along the margin of the foramen magnum was fused to the axis using sublaminar wiring and interposed strut and lateral onlay bone grafts. Ten patients (20%) also underwent atlantoaxial lateral joint fusion by intraarticular instillation of bone chips. In 22 patients (44%) with irreducible dislocation, posterior fusion was preceded by transoral odontoidectomy. In seven patients (14%) with ventral compression, who showed marked clinical improvement on traction despite radiological evidence of persisting atlantoaxial dislocation, occipitocervical fusion was performed without ventral decompression. Seven patients (14%) underwent a single-stage transoral odontoidectomy and posterior fusion. There was no perioperative mortality and the osseous fusion rate was 88%. Of the 43 patients available at follow-up examination (range 3-12 months), 31 patients (72.09%) improved, seven (16.28%) remained the same, and five (11.6%) deteriorated in comparison with their preoperative status. Hence, this technique achieves a stable occipitocervical arthrodesis without supplemental external orthoses and facilitates early postoperative mobilization.

Hemifacial spasm and cerebellopontine angle epidermoid: case report and review.

A case with hemifacial spasm with tinnitus due to right cerebellopontine angle epidermoid is reported. The tumour was supposed to have caused the displacement of the part of anterior inferior cerebellar artery in the vicinity of the root exit zone of the ipsilateral facial nerve. Near total removal of the tumour along with microvascular decompression was done and the patient was completely relieved of his symptoms. The incidence of hemifacial spasm due to cerebellopontine angle epidermoid is extremely low. The cause of such an association is discussed and relevant literature is reviewed.

Intracranial tuberculomas: MRI signal intensity correlation with histopathology and localised proton spectroscopy.

In seven cases of intracranial tuberculomas showing different signal intensities on MRI (five characteristic and two nonspecific), detailed histopathological examination was performed to look for number of macrophages, fibrosis, gliosis, degree of inflammatory cellular infiltrate, and type of caseation. The granulomas showing more macrophages, fibrosis and gliosis appeared hypointense on T2-weighted images. Tuberculomas showing minimal macrophages, marked cellular infiltration, and minimal fibrosis appeared hyperintense on T2-weighted images. Lesions showing similar signal intensity on T2-weighted images showed variation in the amount of macrophages, cellular infiltrates, maturity and fibrosis. Trace element estimation was done (iron, copper, and magnesium) in two of these lesions appearing hypointense on T2 and two normal brain samples; these were significantly lower in tuberculoma compared to normal brain tissue. Localised proton spectroscopy was performed in two hypointense lesions which showed marked increase in peaks in the region of mobile lipids (1.28 ppm) compared to normal brain parenchyma. It is concluded that the signal intensity of the lesions is dependent on the number of macrophages, fibrosis and cellular infiltrates. In addition increased lipid contents in the tuberculoma also contribute to the hypointensity on T2-weighted images.

Prospective evaluation of in vivo proton MR spectroscopy in differentiation of similar appearing intracranial cystic lesions.

Proton MR spectroscopy (PMRS) has been found to be useful in differentiating various cystic intracranial lesions. The purpose of the present study was to prospectively evaluate the spectral pattern of various cystic lesions of brain with similar imaging appearances and to determine the accuracy of this technique in the differential diagnosis of these lesions. Fifty-one patients with intracranial cystic lesions (21 abscesses, 20 gliomas, 3 hydatid cysts, 3 arachnoid cysts, 1 case each of glioependymal cyst, xanthogranuloma, infarction and acoustic neuroma) were evaluated with conventional MR imaging and in vivo PMRS. Ex vivo PMRS of the cystic contents aspirated at surgery in 31 cases was also done to confirm the in-vivo results. Preoperative diagnosis of the lesions was based on the results of in vivo PMRS. In vivo PMRS accurately predicted the pathology in 92% of the cases. We conclude that in-vivo PMRS complements imaging in better characterization of cystic intracranial mass lesions.

In vivo localized proton magnetic resonance spectroscopy of intracranial tuberculomas.

In vivo proton magnetic resonance spectroscopy (MRS) was performed in ten patients with intracranial tuberculomas with the aim of finding biochemical finger prints which may help in the noninvasive diagnosis of the disease. Diagnosis of tuberculoma was confirmed in all these cases retrospectively. Ex vivo spectroscopy of formalin fixed samples of four granulomas and a normal brain (cerebellar) tissue, was performed to confirm the in vivo resonances. The in vivo study showed resonance at 1.3 ppm and 0.9 ppm assigned to methylene group (CH2)n and terminal methyl groups (-CH3) of fatty acids respectively which was subsequently confirmed by the ex vivo study. Large resonances of fatty acids in in vivo study appeared to be due to high lipid content of caseous material. It is concluded that in vivo proton spectroscopy may be helpful in differentiating tuberculomas from other intracranial mass lesions which have diagnostic difficulties on MR imaging.

Multiple infected extradural parasellar hydatid cysts.

BACKGROUND: Intracranial hydatid disease constitutes 1%-2% of all cases of hydatid disease. Multiple, infected, extradural, parasellar hydatid cysts in a patient constitutes an extremely rare presentation. CASE REPORT: This 21-year-old man presented with a progressive left supraclavicular swelling of 3 years duration and raised intracranial pressure of 6 months duration with a past history of left-sided chronic suppurative otitis media that had resolved with antibiotics. On neurologic examination, he had bilateral deterioration of vision with optic atrophy; right temporal field defect; left III, IV, VI, VI, and V2 cranial nerves palsy; and left ear conductive deafness. The patient's E.S.R was raised. His computed tomography (CT) scan showed a hypodense, lobulated lesion in the middle cranial fossa with a hypodense, nonenhancing rim, septations, and focal calcification without perifocal edema. A purulent fluid was aspirated from the left supraclavicular swelling, which did not reveal any organism on staining and culture. Aspiration of the left temporal swelling showed whitish watery fluid, the cytology of which revealed an infected hydatid cyst. Excision of the left temporal extradural, hydatid cysts was done, except the portion of the capsule adherent to the dura, and albendazole was started. One month later, the supraclavicular hydatid cysts were removed. Six months later, a left mastoidectomy was performed for chronic suppurative otitis media. A repeat CT scan showed complete resolution of the hydatid cysts. There was no recurrence at 1 year follow-up. CONCLUSIONS: A rare case of multiple infected extradural hydatid cysts of the parasellar region is reported. The unusual CT picture of a hypodense lobulated mass with septations and a hyperdense rims is presented. The difficulties in its complete excision and successful management with long-term albendazole therapy are discussed.

Growth hormone-producing pituitary tumours: clinical profile and results of surgery.

BACKGROUND: Growth hormone-producing pituitary tumours present with a wide variety of manifestations. The optimum diagnostic work up, management and follow up of such patients is complex and involves a multidisciplinary approach. There is paucity of data from India with regard to the clinical presentation and results of surgery for growth hormone-producing tumours. METHODS: We studied the first 50 patients presenting during 1989-94 with growth hormone-producing pituitary tumours to our centre. The work up included detailed endocrine and radiological assessment. The surgical outcome was analysed for 35 patients who were operated (trans-sphenoidal 29, transcranial 6) at our centre. RESULTS: All the patients had macroadenomas [mean (SD) diameter 3.12 (0.87) cm]. Seventy-five per cent of the patients had supra- and/or parasellar extension and 57% had visual field defects. Tumour size correlated with the preoperative basal (r = 0.57) and glucose-suppressed (r = 0.54) growth hormone levels. Thirty-three of the 35 patients operated at our centre (trans-sphenoidal 28, transcranial 5) were available for follow up (median duration 34 months). After trans-sphenoidal surgery alone, 12 of the 28 (43%) patients had normalization of growth hormone levels (post-glucose growth hormone < 5 ng/ml), and 9 of 11 (82%) showed improvement in visual fields. CONCLUSION: In India, growth hormone-producing pituitary tumours are usually large in size. The growth hormone levels correlate with the size of the tumour. These tumours can be effectively treated by trans-sphenoidal or transcranial surgery.

Hepatic resection for benign liver pathology--report of two cases.

Hepatic resection for benign pathology is rare. We report our experience in two patients with hepaticolithiasis. One patient underwent left hemihepatectomy with removal of segments II, III and IV for localized Caroli's disease with multiple intrahepatic calculi. The second patient underwent resection of segment II and III with Roux-en-Y hepaticojejunostomy for right and left intrahepatic calculi with an abscess in the left lobe of the liver and a choledochal cyst.

Association of lower cranial nerve schwannoma with spinal ependymoma in ? NF2.

A 15 year old male, who had earlier been operated for intraspinal intramedullary ependymoma, subsequently developed a right cerebello pontine (CP) angle mass. A diagnosis of right CP angle ependymoma was considered, in view of established histology of previously operated spinal lesion. Histopathological examination of the well defined extra-axial mass, which was attached with ninth cranial nerve, however revealed a schwannoma. A diagnosis of Neurofibromatosis-2 (NF2) is strongly suspected, because of well established fact, that the spinal ependymomas may have association with lower cranial nerve schwannomas in NF2. Cranial and spinal MRI screening for early diagnosis of associated, asymptomatic lesions, in suspected cases of NF2, particularly in children, is recommended.

Split cord malformation (scm) in paediatric patients: outcome of 19 cases.

There had been considerable debate regarding the surgical outcome of neuro-orthopaedic syndromes (NOS) and neurological syndromes in cases of split cord malformation (SCM). On retrospective analysis of 19 cases of SCM, thirteen were grouped under (Pang) type I and 6 in type II. Their age ranged from 1 month to 9 years (mean 3.5 years). 14 of these were male children. The NOS without neurological signs was detected in 6 cases where as pure neurological signs without NOS were seen in 8 patients. However, the rest 5 had mixed picture of NOS and neurological dysfunction. Nine of 19 cases presented with cutaneous stigmata, mainly in the form of hairy patch. 18 cases had other associated craniospinal anomalies i.e. hydrocephalus, meningomyelocoele, syrinx, dermoid, teratoma etc. Detethering of cord was done in all cases by removal of fibrous/bony septum. Associated anomalies were also treated accordingly. Follow up of these cases ranged from 6 months to 6 years. Six cases of NOS group neither showed deterioration nor improvement, and remained static on follow up. However, four of 8 children with neurological signs showed improvement in their motor weakness, and 1 in saddle hypoaesthesia as well as bladder/bowel function. In 5 cases of mixed group, two had improvement in their weakness and one in hypoaesthesia, but no change was noticed in NOS of this group as well. Hence surgery seemed to be effective, particularly in patients with neurological dysfunction.

Ruptured corpus callosum dermoid : a case report.

A rare case of ruptured dermoid in the region of corpus callosum and lateral ventricle is reported. The CT scan appearance of multiple fat density lesions in the subarachnoid space along with a non-enhancing cyst with or without calcification is pathognomonic of a ruptured dermoid cyst. Early intervention and excision of the dermoid cyst with washing of subarachnoid space and systemic steroids help to reduce the morbidity and mortality.

Medulloblastomas of the cerebellopontine angle.

It is unusual for a medulloblastoma to occur in the cerebellopontine angle (CPA). Four of the total 63 cases of medulloblastoma managed in our department between 1988 to 1998, presented with a mass in the cerebellopontine angle. There were two children amongst these four patients, aged eight and nine years. The other two patients were young adults. Three patients had primary CPA medulloblastoma, while the fourth case had a recurrence in this region, following the excision of the primary vermian tumour. All the four cases were managed by gross total microsurgical excision and craniospinal irradiation. One of the two children, developed subfrontal recurrence after 1 year and 8 months of initial treatment, while the other child developed a large recurrence at primary site, within three months of post-operative irradiation. However, the adult patient developed CPA recurrence and subsequent cervical intramedullary metastasis within two and a half years of diagnosis. These three cases succumbed to their disease, between three months to thirty months of their initial management. However the fourth patient, a 20 years female with desmoplastic variant, was well at two and a half years of follow up.

Infected Ewing's sarcoma of spine.

An unusual case of extradural, intraspinal Ewing's sarcoma with significant extraspinal extension is reported. In view of associated constitutional symptoms, suggestive signs, leucocytosis, elevated ESR and operative findings, the initial diagnosis of Pott's spine was entertained. The lesion however turned out to be infected Ewing's sarcoma on histopathology and bacteriological examination.

Choroid plexus papillomas of the cerebellopontine angle.

The cerebellopontine angle (CPA) is a rare site for the growth of choroid plexus papilloma (CPP). The clinicoradiological diagnosis of this tumor in the CPA is difficult because of the nonspecific clinical presentation and radiological features. Five cases of choriod plexus papilloma (3 males, 2 females) operated upon at this center are reviewed. All the cases were operated upon by retromastoid suboccipital craniectomy. As they all presented with a typical CPA syndrome without any distinctive radiological feature, a clinicoradiological diagnosis of CPP could not be reached in any of these. The diagnosis of CPP could only be suspected at the operation table and established on histopathological examination. Two patients developed recurrences at the primary site following surgery. One patient developed recurrence twice despite gross total excision of tumor in each sitting. Subsequently, this patient remained symptom free for a follow-up period of 1 year. Another patient developed recurrence 2 years following surgery, but he died due to septicemia and aspiration pneumonitis. Therefore definitive surgery could not be performed. Radiotherapy was offered to one of the patients having residual mass post operatively, to render her symptom free for a 4 year follow-up. The remaining two patients have also showed progressive improvement in their symptoms following surgery for 4 years on follow-up. Hydrocephalus was a common feature in all the cases preoperatively, but only one required shunt CSF diversion, because of rapid deterioration in visual equity. In all other cases, hydrocephalus was managed conservatively. Surgery remains the main modality of treatment for CPP, both for primary and recurrent tumors, but radiotherapy may have a role in cases of recurrence, which are quite frequent.

Anterior retropharyngeal approach to the cervical spine.

The anterior retropharyngeal approach (ARPA) accesses anteriorly situated lesions from the clivus to C3, in patients with a short neck, Klippel Feil anomaly or those in whom the C2-3 and C3-4 disc spaces are situated higher in relation to the hyoid bone and the angle of mandible where it is difficult to approach this region using the conventional anterior approach, due to the superomedial obliquity of the trajectory. The ARPA avoids the potentially contaminated oropharyngeal cavity providing for a simultaneous arthrodesis and instrumentation during the primary surgical procedure. Experience of five patients with high cervical extradural compression, who underwent surgery using this approach between 1994 and 1999, is presented. The surgical procedures included excision of ossified posterior longitudinal ligament (n=2); excision of prolapsed disc and osteophytes (n=2); and excision of a vertebral body neoplasm (n=1). Following the procedure, vertebral arthrodesis was achieved using an iliac graft in all the patients. Only one patient with vertebral body neoplasm required an additional anterior cervical plating procedure for stabilisation the construct. The complications included transient respiratory insufficiency and neurological deterioration in two patients; and, pharyngeal fistula and donor site infection in one patient.