Detection of focal lesions in the clot section with negative bone marrow aspirate and trephine biopsy—A series of 5 cases

Bone marrow aspiration and trephine biopsies are commonly used procedures in clinical practice. The practice of making a clot section by using the leftover blood from the bone marrow aspirate material is not a commonly followed practice across centers. A clot section has the advantage of studying the added material with an increased possibility of detecting focal lesions such as myeloma, lymphoma, granuloma, and metastasis in the bone marrow. Bone marrow aspirate, trephine biopsy, and clot section were compared for the detection of focal lesions in a series of 5 patients, 3 of who presented with a history of fever and 2 were already diagnosed cases of Hodgkin lymphoma. Focal lesions were detected in the 5 cases in the clot section alone, whereas bone marrow aspirate and trephine biopsy did not show any focal lesion. Granulomatous infiltration was detected in 3 patients, and lymphomatous infiltration was detected in 2 patients in the clot section, whereas bone marrow aspirate and trephine biopsy were negative for any focal lesion in all 5 cases. A clot section is particularly useful in the detection of bone marrow lesions with a focal distribution. Hence, it must be studied alongside bone marrow aspirate smears, touch smears, and trephine biopsy to increase the diagnostic yield.

Percutaneous endoscopic visualization trephine for thoracic spinal stenosis / 西安交通大学学报(医学版)

【Objective】 To explore the surgical characteristics and clinical efficacy of percutaneous endoscopic visualization trephine for thoracic spinal stenosis. 【Methods】 We made a retrospective analysis of 37 patients with single-segment thoracic spinal stenosis treated with percutaneous endoscopic visualization trephine from January 2019 to June 2020. Among them， there were 14 males and 23 females； their age ranged from 31 to 82 years old， with an average of （57.6±11.8） years old. Their posture， length of hospital stay， length of operation and blood loss were recorded. The visual analogue scale （VAS）， Oswestry disability index （ODI） and the modified Japanese Orthopaedic Association （JOA） score were used to evaluate the preoperative and final conditions of patients and calculate the improvement rate. 【Results】 The operation was successfully completed in all the patients， and no patients developed epidural hematoma， incision infection or postoperative paralysis. Among the 37 patients， 24 ones with ossification of ligamentum flavum （OLF） were in the prone position， and 13 patients had lateral surgery. Among them， thoracic disc herniation （TDH） occurred in 3 cases， OPLL in 5 cases and OLF+OPLL in 5 cases. The hospital stay was （7.2±1.6） days， the operation time was （96.5±20.0） min， and the blood loss was （41.9±10.8） mL. VAS score decreased from （7.0±0.9） to （1.9±0.8）； ODI improved from （41.7±2.1） to （16.1±1.7）； and JOA score increased from （5.8±1.4） to （8.6±1.4）. The preoperative and postoperative differences were statistically significant （P<0.05）. 【Conclusion】 Percutaneous endoscopic visualization of thoracic spinal stenosis is treated by choosing different positions according to the type of compression. The spinal canal is fully decompressed. The surgical method is safe and minimally invasive， and the postoperative effect is satisfactory.

Comparative Analysis of Bone Marrow Aspiration Smears, Touch Imprints and Trephine Biopsy in Haematological Malignancies

Introduction: Inspection of the bone marrow is considered oneof the most valuable diagnostic tool to evaluate hematologicmalignancies. This study compares all three techniques ofbone marrow aspiration (BMA), bone marrow imprint (BMI)and bone marrow biopsy (BMB) in morphological diagnosisof hematological malignancies.Material and methods: The study was conducted on 63selected cases of various hematological malignancies. Onlythose cases in which bone marrow examination was done byusing all the three techniques were included in the study.Results: Out of total 63 cases,53 cases were diagnosed onbone marrow aspirate smears with diagnostic accuracy of84.12%, 60 cases were diagnosed on bone marrow imprintsmears with diagnostic accuracy of 95.23% and all 63 caseswere diagnosed on bone marrow biopsy with diagnosticaccuracy of 100%.Conclusion: It is concluded that bone marrow imprintsare equally useful as bone marrow biopsy in diagnosinghematological malignancies. Imprint cytology shouldtherefore be a standard practice for evaluating bone marrow incases of hematological malignancies.

Role of Immunohistochemistry in Diagnosis and Subtyping of Acute Leukemia using Selected IHC Markers in a Resource Limited Setting

Introduction: In resource limited settings where geneticstudies and flow cytometry were not routinely done oravailable, morphology is primarily used for diagnosis andsubtyping of acute leukemias with use of ancillary tests likecytochemistry and immunohistochemistry in selected casesfor a more accurate and definitive diagnosis. This study wasdone to assess the role of immunohistochemistry in diagnosisand subtyping of acute leukemias in resource poor settingusing selected IHC markers and to find diagnostic accuracy ofmorphologic diagnosis.Material and methods: The study was done on 45 selectedcases of acute leukemia. Immunohistochemistry was doneon all cases for typing and confirmation of diagnosis aftermorphological examination of peripheral blood smears andall three bone marrow preparations.A limited panel of IHCmarkers were used including Anti MPO, Anti CD3, AntiCD20, Anti CD22, Anti TdT, Anti CD117, Anti CD15 andAnti CD68(KP1) for immunohistochemistry.Results: The accuracy of morphological diagnosis in casesof AML and ALL in the study was 84.09% and 82.22%respectively. By intercalating immunohistochemical studieswith morphological examination almost all cases of acuteleukemia can be diagnosed and subclassified, and diagnosticaccuracy is increased as compared to morphologicalexamination alone.Conclusion: Though morphology remains thegold standard for paraffin embedded bone marrowtrephines,immunohistochemical staining has became anintegral part of diagnostic workup in cases of hematologicmalignancies in limited resource settings.

Trephine Transverse Colostomy Is Effective for Patients Who Have Previously Undergone Rectal Surgery

PURPOSE: Colostomy creation is an essential procedure for colorectal surgeons, but the preferred method of colostomy varies by surgeon. We compared the outcomes of trephine colostomy creation with open those for the (laparotomy) and laparoscopic methods and evaluated appropriate indications for a trephine colostomy and the advantages of the technique. METHODS: We retrospectively evaluated 263 patients who had undergone colostomy creation by trephine, open and laparoscopic approaches between April 2006 and March 2016. We compared the clinical features and the operative and postoperative outcomes according to the approach used for stoma creation. RESULTS: One hundred sixty-three patients (62%) underwent colostomy surgery for obstructive causes and 100 (38%) for fistulous problems. The mean operative time was significantly shorter with the trephine approach (trephine, 46.0 ± 1.9 minutes; open, 78.7 ± 3.9 minutes; laparoscopic, 63.5 ± 5.0 minutes; P < 0.001), as was the time to flatus (1.8 ± 0.1 days, 2.1 ± 0.1 days, 2.2 ± 0.3 days, P = 0.025). Postoperative complications (<30 days) were not different among the 3 approaches (trephine, 4.3%; open, 1.2%; laparoscopic, 0%; P = 0.828). In patients who underwent rectal surgery, a trephine colostomy was feasible for a diversion colostomy (P < 0.001). CONCLUSION: The trephine colostomy is safe and can be implemented quickly in various situations, and compared to other colostomy procedures, the patient's recovery is faster. Previous laparotomy history was not a contraindication for a trephine colostomy, and a trephine transverse colostomy is feasible for patients who have undergone previous rectal surgery.

Application of trephine craniotomy in traumatic posterior cranial fossa hematoma / 中国基层医药

Objective To study the application of the annular drilling in the operation of traumatic intracra-nial hematoma.Methods The clinical data of 31 cases of posterior cranial fossa hematoma were analyzed retrospec-tively.Results In 31 patients,the operation was successful and the hematoma was satisfactory.After the injury,the GOS score,22 cases recovered,8 cases of mild disability,1 case of severe disability,no case of plant survival and death.Conclusion It has high hematoma removal rate and a satisfactory recovery after surgery for traumatic posterior cranial fossa hematoma.The size and scope of the posterior fossa craniotomy are restricted by bone window, so we should have a good knowledge of the surgical indications and contraindications.

Trephine Colostomy: Minimally Invasive Stoma Technique.

Aims: Stoma is an important part of surgical management of numerous malignant or benign anorectal diseases and anorectal injuries. This can be performed without recourse to laparatomy. This study was aimed to assess the outcome of trephine to loop sigmoid colostomy creation. Study Design: The retrospective study included 18 patients who underwent trephine colostomy due to various conditions including Fournier’s gangrene, inoperable anorectal cancer, recto-vaginal fistula, fecal incontinence, and rectal injury. Place and Duration of Study: Izmir Katip Celebi University Ataturk Training and Research Hospital, Department of Surgery between January 2005 and January 2015. Methodology: The retrospective study included 18 patients who underwent trephine colostomy. Demographic characteristics, primary pathology for colostomy decision, length of hospital stay, anesthesia technique, and early period surgical complications at 3 months were recorded. Results: Patients comprised 11 males and 7 women with a mean age of 53±5 years. The indications for stoma formation were Fournier’s gangrene in 8 cases, inoperable anorectal cancer in 3 cases, high recto-vaginal fistula in 2 cases, fecal incontinence in 3 cases and rectal injury in 2 cases. Regional anesthesia was performed in 12 and general anesthesia in 6 cases. Only one patient (5.6%) had stricture of the stoma. There were no other complications and no additional morbidity and mortality related to TS technique. Conclusion: Trephine stoma is a relatively simple, safe and rapid procedure and an effective alternative to colostomy formation without laparotomy indications.

Prospective study of bone marrow in haematological disorders.

Background: Bone marrow examination is useful in the diagnosis of both hematological and non-hematological disorders. The two most important techniques used for the diagnosis of hematological disorders are bone marrow aspiration and trephine biopsy which are complementary to each other. The present study is to evaluate the findings of bone marrow aspiration & trephine biopsy and their cytological and histological patterns in various hematological disorders. The aim of the study is to evaluate the clinical profile, spectrum, cytological and histological pattern of various hematological disorders reported in bone marrow aspiration and trephine biopsy respectively. Methods: It was a cross-sectional study design with 105 patients who underwent bone marrow examination for evaluation of hematological disorders in the Department of pathology, Andhra Medical College during the period of 2012 to 2014. Results: Among 105 cases studied, age of patients ranged from 1 to 68 yrs with mean age of 32.4 yrs and male predominance (1.5:1). Most of the patients presented with fever, shortness of breath, Easy fatigability and generalized weakness. The commonest physical findings were pallor followed by splenomegaly & hepatomegaly and in hematological parameters predominantly pancytopenia. Bone marrow aspiration was diagnostic in 53(50%) cases and trephine biopsy was diagnostic in 52(50%) cases. Anemias (50%) and leukemias (16%) are most common hematological disorders. Among the anemias, megaloblastic anemia is the most common (40%) cause of hematological non-malignancies. Among leukemias, acute myeloid leukemias are common cause of hematological malignancies. Conclusion: The present study showed the usefulness of bone marrow aspiration and trephine biopsy in evaluation of the bone marrow in routine haematological disorders and also for understanding disease progression, for diagnosis and therapeutic evaluation. These are also helpful in planning further investigation and management.

Evaluación de un nuevo método de remoción quirúrgica de implantes oseointegrados considerados en fallo / Evaluation of a new surgical removal method of failed integrated implants

OBJETIVO El objetivo del presente estudio descriptivo es la valoración de un nuevo método de remoción de implantes oseointegrados bajo una técnica mínimamente invasiva. MATERIALES Y MÉTODOS El estudio fue desarrollado sobre un grupo de 66 implantes oseointegrados de conexión interna y externa diagnosticados en falla, a los cuales se les indicó su remoción quirúrgica por presentar un diagnóstico radiográfico de pérdida ósea periimplantaria, mal posicionamiento quirúrgico con imposibilidad de rehabilitación protésica o daño del elemento de retención protésico del implante. El procedimiento quirúrgico, el cual es de carácter ambulatorio, fue llevado a cabo en un pabellón bajo anestesia local. Como primera opción de remoción quirúrgica, el procedimiento consistió en la utilización de instrumental de remoción a contra-torque, sin la apertura de un colgajo de espesor total, y como segunda opción de remoción quirúrgica la utilización de una fresa trefina, para lo cual fue necesario realizar un colgajo de espesor total que expusiera el lecho implantario. RESULTADOS Se removieron un total de 66 implantes oseointegrados, todos bajo la primera modalidad de remoción a contra-torque con el nuevo instrumento, sin colgajo y sin la necesidad de usar fresa trefina. CONCLUSIONES Con las limitaciones de este estudio preliminar planteamos que la utilización del nuevo instrumento de remoción a contra-torque de implantes oseointegrados en fallo se vislumbra como una muy buena alternativa de remoción quirúrgica mínimamente invasiva, disminuyendo los riesgos quirúrgicos del uso de una fresa trefina, el daño a los tejidos aledaños.

OBJECTIVE The aim of this study is the evaluation of a new removal method of osseointegrated implants under a minimally invasive technique. MATERIALS AND METHODS The study was conducted on a group of 66 osseointegrated internal and external connection implants that were considered unsuccesful. The surgical removal was indicated after radiologically confirming peri-implant bone loss, and poor positioning which made the prosthetic rehabilitation impossible, or would damage the prosthetic implant retainer. The surgical procedure was developed in an operating room under local anesthesia. As first surgical removal option, the procedure consisted of the use of a removal instrument that works against torque and which does not need a full thickness flap to reach the surgical site; and as a second surgical removal option a trephine bur was used. For this option, a full thickness flap was performed in order to expose the surgical site. RESULTS A total of 66 osseointegrated implants were removed under the first mode, with no full thickness flaps or Trephine burs required. CONCLUSIONS Within the limitations of this preliminary study, we propose that the use of this new, against torque, removal instrument of osseointegrated implants in failure is seen as a very good alternative to invasive surgical removal techniques, reducing surgical risks.

Diagnosis and treatment of massive bilateral chronic subdural hematoma in elderly patients by clinical analysis of 25 cases / 中国医师进修杂志

Objective To explore particularity of the diagnosis and treatment with massive bilateral chronic subdural hematoma (BCSDH) in elders.Method The clinical data of 25 elders with BCSDH treated in our hospital from 2007 to 2011 were analyzed retrospectively.All patients were examined with computerized tomography (CT) of 25 patients through the bilateral trephined hole.Results Twenty-four patients recovered better,the symptom significantly improved.After operative 1 month,14 patients? hematoma disappear,6 patents only had little bilateral subdural effusion,4 patents only had little unilateral subdural effusion.One patient appeared massive subdural effusion on the second day after operation,the familiality gave up therapy,and the patient was dead.Conclusion CT scanning should be taken before you make correct diagnisis.Bilateral single twist-drill craniostomy with irrigation and drainage is a chief method to massive BCSDH.

Diagnostic Assessment of Bone Marrow Aspiration Smears, Touch Imprints and Trephine Biopsy in Non- Haematological Disorders.

Diagnostic Assessment of bone marrow aspirate particle smears, imprints and biopsy sections was done on 10 Non- Haematological disorders. Core needle biopsy of the bone marrow is a safe and useful procedure. It is a valuable diagnostic aid for measurement of marrow cellularity, metastatic tumours and fibrosis . Bilateral trephine biopsy was conducted wherever necessary. Touch imprints were useful for studying cell morphology, where aspiration yielded dry tap.All the three procedures of bone marrow aspiration, trephine biopsy and touch imprints were found to be complementary to each other and superiority of one method over the other depended on the specific disease process.

The Effectiveness of Lacrimal Trephination for the Treatment of Canalicular Obstruction

PURPOSE: To determine the effectiveness of lacrimal trephination to treat canalicular obstruction. METHODS: Silicone intubation following lacrimal trephination was performed in 38 eyes of 29 patients with epiphora due to canalicular obstruction between December 2005 and October 2009. Medical records were retrospectively reviewed and telephone interviews were performed. The severity of epiphora was graded by Munk's scale, and anatomical improvement was evaluated by postoperative probing and syringing. RESULTS: The procedure was successful in 73.7% of the cases (grade 0 or 1), and 68.4% of the eyes had complete resolution of epiphora (grade 0). The anatomical success rate was 81.6%. CONCLUSIONS: Lacrimal trephination is a simple and effective treatment for canalicular obstructions. Therefore, lacrimal trephination could be performed prior to attempting an invasive conjunctivodacryocystorhinostomy.

Analysis of Factors Affecting Corneal Endothelial Cell Loss after Penetrating Keratoplasty

PURPOSE: To evaluate the factors affecting corneal endothelial cell loss after penetrating keratoplasty in a long-term follow-up. METHODS: Donor age, post-mortem time, storage time, underlying disease, elevation of IOP after surgery, underlying glaucoma, and trephine size were analyzed in 76 eyes. Postoperative corneal endothelial density was measured after 1, 3, 6, and 12 months. Patients who experienced graft rejection were excluded. RESULTS: Donor age and endothelial loss were correlated in all patients (t-value = 1.98); however, post-mortem time and storage time were not statistically significant (t 2 < 2). Endothelial cell loss was more severe in the bullous keratopathy patient group than it was in the keratoconus patient group, but this difference was not statistically significant (p-value = 0.154). The number of anti-glaucomatous eye drops showed positive correlation with the declining rate of endothelial cells (t-value = 1.975). Existence of glaucoma diagnosed before surgery did not statistically influence endothelial cell loss. Additionally, in the bullous keratopathy patient group, an inverse correlation between endothelial cell loss and trephine diameter was observed (t-value = -2.859). CONCLUSIONS: Old donor age, small trephine size in bullous keratopathy, and post-operative IOP elevation are risk factors for increased endothelial cell loss following penetrating keratoplasty.

Diagnostic Assessment of Bone Marrow Aspiration Smears, Touch Imprints and Trephine Biopsy in Haematological Disorders.

Diagnostic Assessment of bone marrow aspirate particle smears, imprints and biopsy sections was done on 40 haematological disorders. Core needle biopsy of the bone marrow is a safe and useful procedure. It is a valuable diagnostic aid for measurement of marrow cellularity and fibrosis.Bilateral trephine biopsy was conducted wherever necessary.Bone marrow aspiration was the most effective method for studying morphological details and was able to diagnose most of the cases except the 2 cases of myelofibrosis which yielded dry tap for which trephine biopsy was diagnostic.Trephine biopsy was also found to be superior for staging of lymphomas and to study the ALIP in MDS.Touch imprints were useful for studying cell morphology, where aspiration yielded dry tap.All the three procedures of bone marrow aspiration, trephine biopsy and touch imprints were found to be complementary to each other and superiority of one method over the other depended on the specific disease process.

Modified model of sub-critical size cranial defect in the rabbit / Modelo modificado de defecto craneal de tamaño subcrítico de conejo

In medical sciences, any experimental animal model should be reproducible and adequate to the purpose of simulated human physiological response. In bone injury response research, when bone substitutes are in use, it is of primary importance that studied defects fail to heal unless treated with the tissue engineering therapy under study. This failure defines the concept of "critical size defect" (CSD) wich has different limits according to the animal species used and the location of the defect. Although this is a basic concept, when the aim of the study is to investigate the interface Bone-Biomaterial, it is of primary importance to obtain as much contact area as possible. In order to do so, we propose a modified surgical approach to the classical bi-parietal round sub-critical defect model in rabbit vault.

En las ciencias médicas, cualquier modelo animal de experimentación debe ser reproducible y ajustado al propósito de simular la respuesta fisiológica humana. En la investigación de la respuesta a la lesión ósea, cuando son utilizados sustitutos óseos, es de gran importancia el estudio de defectos que no logran sanar, a menos que sean tratados con terapia de ingeniería de tejidos. Este fracaso define el concepto de "defecto de tamaño crítico" (CDS) el cual tiene límites diferentes según la especie animal utilizada y la ubicación del defecto. Aunque se trata de un concepto básico, cuando el objetivo del estudio es investigar la interfaz hueso-biomaterial, es de primordial importancia obtener la máxima superficie de contacto que sea posible. Para ello, se propone una modificación en el enfoque quirúrgico del modelo clásico de defecto de tamaño subcrítico biparietal en la bóveda de conejo.

Bone marrow biopsy in non-Hodgkin lymphoma: A morphological study.

Context: Bone marrow (BM) biopsy is an integral part of staging work-up for non-Hodgkin lymphoma (NHL). Aims: To study the characteristics of BM involvement in NHL with respect to incidence, histologic pattern and morphology of infiltration and its discordance with the histology of primary anatomic site. Settings and Design: Forty-nine cases of NHL in which BM biopsy was performed for staging were included in this study, the primary site being classified according to the WHO classification for NHL. Materials and Methods: A prospective study of 49 cases was conducted. Bilateral BM biopsy was obtained from the posterior superior iliac spine. The biopsies were fixed in 10% buffered formalin solution and decalcified using 10% formal - formic acid for 4 - 6 h followed by routine processing. The serial sections were stained by hematoxylin and eosin and reticulin stains. Results: BM biopsy showed involvement by lymphoma in 27 cases (55.10%). Unilateral positivity was found in four cases (14.81% cases). The overall incidence of marrow involvement by NHL was 55.1%. The incidence of involvement was higher in T-cell lymphomas when compared with B-cell lymphomas and predominant pattern of involvement was mixed. Diffuse large B-cell lymphomas had the lowest incidence in all the B-cell lymphomas. A discordant histology between BM and primary anatomic site was found in 29.63% (8/27) of the cases, where it was seen more in follicular lymphomas and diffuse large B-cell lymphomas. Conclusions: Critical examination of BM biopsies can increase the diagnostic accuracy, thereby contributing to the prognosis and appropriate treatment modalities.

Ballooning Canaliculoplasty and Silicone Tube Intubation after Lacrimal Trephination

PURPOSE: The purpose of this study was to assess the satety and effectiveness of lacrimal trephination and balloon dilatation in treatment of obstruction of the lacrimal canaliculus. METHODS: Lacrimal trephination and subsequent balloon dilation was performed in 7 eyes of 7 consecutive patients with epiphora due to lacrimal canalicular obstruction and common canalicular obstruction. RESULTS: The average age of patients was 50.3 years old and the average follow-up period was 17.7 months. Anatomical success was 7 of 7 eyes (100%) and functional success , resolution of epiphora was 5 of 7 eyes (71%) CONCLUSIONS: Lacrimal trephination and subsequent ballooning canaliculoplasty in treatment of obstruction of the lacrimal canaliculus seems to be safe and valuable as an primary procedure before Jones tube bypass surgery.

Canalicular Trephination with Lacrimal Trephine and Endoscopic DCR

PURPOSE: The purpose of this study is to evaluate surgical outcomes of canalicular trephination with lacrimal trephine and endoscopic dacryocystorhinostomy in patiens with common canalicular or canalicular obstruction. METHODS: 35 patients (38 eyes) diagnosed as common canalicular or canalicular obstruction undergoing surgery between December 1999 and August 2003. Patients have been followed up more than 5 months after surgery. RESULTS: The average age of patients was 57.3 years old and the average follow-up period was 7.1 months. The overall success rate was 92.1%. With obstructions within lower canaliculus, the success rate was 75.0%. The success rate of the cases with obstructions within upper canaliculus and upper and lower canaliculus was 100%, and the success rate of the cases with obstructions within common canaliculus was 95.2%. CONCLUSIONS: The surgical success rate of canalicular trephination with lacrimal trephine and endonasal dacryocystorhinostomy was better than canaliculodacryocystorhinostomy and this seems to be adequate as an primary procedure before Jones tube bypass surgery.

Treatment of Common Canalicular Obstruction Using Lacrimal Trephine

Conjunctivodacryocystorhinostom.y using Jones tube has been the treatment of choice for patients with epiphora due to common canalicular obstruction. But this procedure carries a lot of disadvantages including external scar formation and many complications result from general anesthesia, and necessity of permanent prosthesis and long-term follow-up. So authors have used a new instrument, the lacrimal trephine designed for creating an opening through 8 distally occluded lacrimal canaliculus to treat the common canalicular obstruction. From June 1996 to December 1996, we performed 8 lacrirnal trephination with silicone tube insertion in five patients diagnosed as common canalicu-lar obstruction. All of them have achieved the anatomical success and four of thein have shown clinical success.

Trephination with vacuum trephine in undercorrection of myopic epikeratoplasty

For the treatment of undercorrection after myopic epikeratoplasty, early suture removal, scar revision, retrephination, replacement of lenticule and, recently, excimer laser photorefractive keratoplasty have been employed. We performed trephination with Hessburg-Barron vacuum trephine on 11 eyes of 11 patients whose post-epikeratoplasty myopic power was over -4.00 diopters for 3 consecutive months. Patients were followed up on post-trephination 1 month, 3 months and 6 months. The mean duration from epikeratoplasty to trephination was 14.27 months, the mean pre-trephination spherical equivalent was -8.50 D and the mean keratometric reading was 40.87 D. The mean reduction of spherical equivalent was -4.07, -5.99, -8.02 D at post-trephination 1, 3, 6 months, respectively. The mean keratometric reading was 37.60 diopters at 1 month and 41.53 diopters at 6 months. At 1 and 3 months, there were significant reductions of myopic power in refraction and keratometry (p 0.05). There was no change of uncorrected and best corrected visual acuity between baseline and post-trephination 6 months.